National Library of Energy BETA

Sample records for monochromator zone-plate linear

  1. Renewable liquid reflecting zone plate

    DOE Patents [OSTI]

    Toor, Arthur; Ryutov, Dmitri D.

    2003-12-09

    A renewable liquid reflecting zone plate. Electrodes are operatively connected to a dielectric liquid in a circular or other arrangement to produce a reflecting zone plate. A system for renewing the liquid uses a penetrable substrate.

  2. Mirror monochromator

    SciTech Connect (OSTI)

    Mankos, Marian; Shadman, Khashayar

    2014-12-02

    In this SBIR project, Electron Optica, Inc. (EOI) is developing a mirror electron monochromator (MirrorChrom) attachment to new and retrofitted electron microscopes (EMs) for improving the energy resolution of the EM from the characteristic range of 0.2-0.5 eV to the range of 10-50 meV. This improvement will enhance the characterization of materials by imaging and spectroscopy. In particular, the monochromator will refine the energy spectra characterizing materials, as obtained from transmission EMs [TEMs] fitted with electron spectrometers, and it will increase the spatial resolution of the images of materials taken with scanning EMs (SEMs) operated at low voltages. EOIs MirrorChrom technology utilizes a magnetic prism to simultaneously deflect the electron beam off the axis of the microscope column by 90 and disperse the electrons in proportional to their energies into a module with an electron mirror and a knife-edge. The knife-edge cuts off the tails of the energy distribution to reduce the energy spread of the electrons that are reflected, and subsequently deflected, back into the microscope column. The knife-edge is less prone to contamination, and thereby charging, than the conventional slits used in existing monochromators, which improves the reliability and stability of the module. The overall design of the MirrorChrom exploits the symmetry inherent in reversing the electron trajectory in order to maintain the beam brightness a parameter that impacts how well the electron beam can be focused downstream onto a sample. During phase I, EOI drafted a set of candidate monochromator architectures and evaluated the trade-offs between energy resolution and beam current to achieve the optimum design for three particular applications with market potential: increasing the spatial resolution of low voltage SEMs, increasing the energy resolution of low voltage TEMs (beam energy of 5-20 keV), and increasing the energy resolution of conventional TEMs (beam energy of 80-120 keV). Specialized software packages that have been developed by MEBS, Ltd. were used to calculate the electron optical properties of the key monochromator components: namely, the magnetic prism, the electron mirror, and the electron lenses. In the final step, these results were folded into a model describing the key electron-optical parameters of the complete monochromator. The simulations reveal that the mirror monochromator can reduce the energy spread of a Schottky electron source, an established electron emitter used widely in EMs, to 10 meV for practical beam current values and that further reduction of the energy spread down to 3 meV is possible for low current applications with a Cold Field Emitter (an electron source with 10x the brightness of a Schottky source). MirrorChroms can be designed and built to attach to different types of TEMs and SEMs, thus making them suitable for enhancing the study of the structure, composition, and bonding states of new materials at the nanoscale to advance material science research in the field of nanotechnology as well as biomedical research.

  3. Monochromator Crystal Glitch Library

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    SSRL's Monochromator Crystal Glitch Library allows users to view glitch spectra online, list specific crystal orientations, and download PDF files of the glitch spectra. (Specialized Interface)

  4. Demonstration of 12 nm resolution Fresnel zone plate lens based soft x-ray microscopy

    SciTech Connect (OSTI)

    Chao, W.; Kim, J.; Rekawa, S.; Fischer, P.; Anderson, E. H.

    2009-06-05

    To extend soft x-ray microscopy to a resolution of order 10 nm or better, we developed a new nanofabrication process for Fresnel zone plate lenses. The new process, based on the double patterning technique, has enabled us to fabricate high quality gold zone plates with 12 nm outer zones. Testing of the zone plate with the full-field transmission x-ray microscope, XM-1, in Berkeley, showed that the lens clearly resolved 12 nm lines and spaces. This result represents a significant step towards 10 nm resolution and beyond.

  5. Pulsed-neutron monochromator

    DOE Patents [OSTI]

    Mook, Jr., Herbert A. (Oak Ridge, TN)

    1985-01-01

    In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The wave are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.

  6. Pulsed-neutron monochromator

    DOE Patents [OSTI]

    Mook, H.A. Jr.

    1984-01-01

    In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The waves are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.

  7. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Wednesday, 31 August 2005 00:00 Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their

  8. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their chemical elements and measure magnetic and other properties as well. Now a new method for creating optical

  9. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their chemical elements and measure magnetic and other properties as well. Now a new method for creating optical

  10. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their chemical elements and measure magnetic and other properties as well. Now a new method for creating optical

  11. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution Print Analytical tools that combine spatial resolution with elemental and chemical identification at the nanometer scale along with large penetration depth are indispensable for the life and physical sciences. The XM-1 soft x-ray microscope at the ALS produces images that not only reveal structures but can identify their chemical elements and measure magnetic and other properties as well. Now a new method for creating optical

  12. APS high heat load monochromator

    SciTech Connect (OSTI)

    Lee, W.K.; Mills, D.

    1993-02-01

    This document contains the design specifications of the APS high heat load (HHL) monochromator and associated accessories as of February 1993. It should be noted that work is continuing on many parts of the monochromator including the mechanical design, crystal cooling designs, etc. Where appropriate, we have tried to add supporting documentation, references to published papers, and calculations from which we based our decisions. The underlying philosophy behind performance specifications of this monochromator was to fabricate a device that would be useful to as many APS users as possible, that is, the design should be as generic as possible. In other words, we believe that this design will be capable of operating on both bending magnet and ID beamlines (with the appropriate changes to the cooling and crystals) with both flat and inclined crystal geometries and with a variety of coolants. It was strongly felt that this monochromator should have good energy scanning capabilities over the classical energy range of about 4 to 20 keywith Si (111) crystals. For this reason, a design incorporating one rotation stage to drive both the first and second crystals was considered most promising. Separate rotary stages for the first and second crystals can sometimes provide more flexibility in their capacities to carry heavy loads (for heavily cooled first crystals or sagittal benders of second crystals), but their tuning capabilities were considered inferior to the single axis approach.

  13. Fresnel zone plate stacking in the intermediate field for high efficiency focusing in the hard X-ray regime

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gleber, Sophie -Charlotte; Wojcik, Michael; Liu, Jie; Roehrig, Chris; Cummings, Marvin; Vila-Comamala, Joan; Li, Kenan; Lai, Barry; Shu, Deming; Vogt, Stefan

    2014-11-05

    Focusing efficiency of Fresnel zone plates (FZPs) for X-rays depends on zone height, while the achievable spatial resolution depends on the width of the finest zones. FZPs with optimal efficiency and sub-100-nm spatial resolution require high aspect ratio structures which are difficult to fabricate with current technology especially for the hard X-ray regime. A possible solution is to stack several zone plates. To increase the number of FZPs within one stack, we first demonstrate intermediate-field stacking and apply this method by stacks of up to five FZPs with adjusted diameters. Approaching the respective optimum zone height, we maximized efficiencies formorehigh resolution focusing at three different energies, 10, 11.8, and 25 keV.less

  14. Focusing monochromators for high energy synchrotron radiation

    SciTech Connect (OSTI)

    Suortti, P. )

    1992-01-01

    Bent crystals are introduced as monochromators for high energy synchrotron radiation. The reflectivity of the crystal can be calculated reliably from a model where the bent crystal is approximated by a stack of lamellas, which have a gradually changing angle of reflection. The reflectivity curves of a 4 mm thick, asymmetrically cut ({chi}=9.5{degree}) Si(220) crystal are measured using 150 keV radiation and varying the bending radius from 25 to 140 m. The width of the reflectivity curve is up to 50 times the Darwin width of the reflection, and the maximum reflectivity exceeds 80%. The crystal is used as a monochromator in Compton scattering measurements. The source is on the focusing circle, so that the resolution is limited essentially by the detector/analyzer. A wide bandpass, sharply focused beam is attained when the source is outside the focusing circle in the transmission geometry. In a test experiment. 10{sup 12} photons on an area of 2 mm{sup 2} was observed. The energy band was about 4 keV centered at 40 keV. A powder diffraction pattern of a few reflections of interest was recorded by an intrinsic Ge detector, and this demonstrated that a structural transition can be followed at intervals of a few milliseconds.

  15. Asymmetrically cut crystals for synchrotron radiation monochromators

    SciTech Connect (OSTI)

    Sanchez del Rio, M. ); Cerrina, F. )

    1992-01-01

    Asymmetrically cut crystals are interesting for use in synchrotron radiation monochromators because of their good energy resolution characteristics and their focusing properties. Ray tracing codes, such as SHADOW, are very efficient in the design and development of new optical devices. In order to determine the convenience of using asymmetrically cut crystals for x-ray monochromators, SHADOW has been extended to include these kinds of crystals. The physical approach to ray tracing asymmetrically cut crystals is based on the coexistence of two periodic structures. One of these is the bulk periodic structure of the Bragg planes. Such a structure determines the existence of a rocking curve near the Bragg condition, and is implemented in SHADOW following the Darwin--Prins formalism of the dynamical theory of diffraction. The second periodic structure is a one-dimensional grating on the crystal surface, formed by the truncation of the lattice planes with the surface. This grating is responsible for the focusing properties of these crystals and plays an essential role in determining the trajectory of the rays. The combination of an asymmetric crystal and a nonplanar surface can be easily achieved by bending (Johann case) to provide improved properties. More complex cases such as the ground-bent crystals (i.e., Johansson geometry) can be considered as a particular case of asymmetrical crystals in which the angle between the Bragg planes and the surface change along the crystal surface. All these cases have been implemented in SHADOW.

  16. Holographic optical grating and method for optimizing monochromator configuration

    DOE Patents [OSTI]

    Koike, Masato (Moraga, CA)

    1999-01-01

    This invention comprises a novel apparatus for recording a holographic groove pattern on a diffraction grating blank. The recording apparatus is configured using newly developed groups of analytical equations. The invention further comprises the novel holographic diffraction grating made with the inventive recording apparatus. The invention additionally comprises monochromators and spectrometers equipped with the inventive holographic diffraction grating. Further, the invention comprises a monochromator configured to reduce aberrations using a newly developed group of analytical equations. Additionally, the invention comprises a method to reduce aberrations in monochromators and spectrometers using newly developed groups of analytical equations.

  17. High energy resolution, high angular acceptance crystal monochromator

    DOE Patents [OSTI]

    Alp, Ercan E. (Bolingbrook, IL); Mooney, Timothy M. (Westmont, IL); Toellner, Thomas (Green Bay, WI)

    1996-06-04

    A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut single crystal of higher order reflection in a nested geometric configuration. In the disclosed embodiment, a highly asymmetrically cut (.alpha.=20) outer silicon crystal (4 2 2) with low order reflection is combined with a symmetrically cut inner silicon crystal (10 6 4) with high order reflection to condition a hard x-ray component (5-30 keV) of synchrotron radiation down to the .mu.eV-neV level. Each of the crystals is coupled to the combination of a positioning inchworm and angle encoder via a respective rotation stage for accurate relative positioning of the crystals and precise energy tuning of the monochromator.

  18. High energy resolution, high angular acceptance crystal monochromator

    DOE Patents [OSTI]

    Alp, E.E.; Mooney, T.M.; Toellner, T.

    1996-06-04

    A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut single crystal of higher order reflection in a nested geometric configuration. In the disclosed embodiment, a highly asymmetrically cut ({alpha}=20) outer silicon crystal (4 2 2) with low order reflection is combined with a symmetrically cut inner silicon crystal (10 6 4) with high order reflection to condition a hard x-ray component (5--30 keV) of synchrotron radiation down to the {micro}eV-neV level. Each of the crystals is coupled to the combination of a positioning inchworm and angle encoder via a respective rotation stage for accurate relative positioning of the crystals and precise energy tuning of the monochromator. 7 figs.

  19. Synchronized monochromator and insertion device energy scans at SLS

    SciTech Connect (OSTI)

    Krempasky, J.; Flechsig, U.; Korhonen, T.; Zimoch, D.; Quitmann, Ch.; Nolting, F.

    2010-06-23

    Synchronous monochromator and insertion device energy scans were implemented at the Surfaces/Interfaces:Microscopy (SIM) beamline in order to provide the users fast X-ray magnetic dichroism studies (XMCD). A simple software control scheme is proposed based on a fast monochromator run-time energy readback which quickly updates the insertion device requested energy during an on-the-fly X-ray absorption scan (XAS). In this scheme the Plain Grating Monochromator (PGM) motion control, being much slower compared with the insertion device (APPLE-II type undulator), acts as a 'master' controlling the undulator 'slave' energy position. This master-slave software implementation exploits EPICS distributed device control over computer network and allows for a quasi-synchronous motion control combined with data acquisition needed for the XAS or XMCD experiment.

  20. Monochromator for continuous spectrum x-ray radiation

    DOE Patents [OSTI]

    Staudenmann, J.L.; Liedl, G.L.

    1983-12-02

    A monochromator for use with synchrotron x-ray radiation comprises two diffraction means which can be rotated independently and independent means for translationally moving one diffraction means with respect to the other. The independence of the rotational and translational motions allows Bragg angles from 3.5/sup 0/ to 86.5/sup 0/, and facilitates precise and high-resolution monochromatization over a wide energy range. The diffraction means are removably mounted so as to be readily interchangeable, which allows the monochromator to be used for both non-dispersive and low dispersive.

  1. Monochromator for continuous spectrum x-ray radiation

    DOE Patents [OSTI]

    Staudenmann, Jean-Louis (Ames, IA); Liedl, Gerald L. (West Lafayette, IN)

    1987-07-07

    A monochromator for use with synchrotron x-ray radiation comprises two diffraction means which can be rotated independently and independent means for translationally moving one diffraction means with respect to the other. The independence of the rotational and translational motions allows Bragg angles from 3.5.degree. to 86.5.degree., and facilitates precise and high-resolution monochromatization over a wide energy range. The diffraction means are removably mounted so as to be readily interchangeable, which allows the monochromator to be used for both non-dispersive and low dispersive work.

  2. Optical system for high resolution spectrometer/monochromator

    DOE Patents [OSTI]

    Hettrick, M.C.; Underwood, J.H.

    1988-10-11

    An optical system for use in a spectrometer or monochromator employing a mirror which reflects electromagnetic radiation from a source to converge with same in a plane is disclosed. A straight grooved, varied-spaced diffraction grating receives the converging electromagnetic radiation from the mirror and produces a spectral image for capture by a detector, target or like receiver. 11 figs.

  3. Study of a scattering shield in a high heat load monochromator (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Study of a scattering shield in a high heat load monochromator Citation Details In-Document Search Title: Study of a scattering shield in a high heat load monochromator Authors: Huang, Rong ; Meron, Mati [1] ; HWMRI) [2] + Show Author Affiliations (UC) [UC ( Publication Date: 2014-02-04 OSTI Identifier: 1091969 Resource Type: Journal Article Resource Relation: Journal Name: Nucl. Instrum. Methods A; Journal Volume: 716; Journal Issue: 07, 2013 Research Org:

  4. Commissioning of a Soft X-ray Beamline PF-BL-16A with a Variable-Included-Angle Varied-Line-Spacing Grating Monochromator

    SciTech Connect (OSTI)

    Amemiya, Kenta; Toyoshima, Akio; Kikuchi, Takashi; Kosuge, Takashi; Nigorikawa, Kazuyuki; Sumii, Ryohei; Ito, Kenji

    2010-06-23

    The design and commissioning of a new soft X-ray beamline, BL-16A, at the Photon Factory is presented. The beamline consists of a pre-focusing mirror, an entrance slit, a variable-included-angle varied-line-spacing plane grating monochromator, and a post-focusing system as usual, and provides circularly and linearly polarized soft X rays in the energy range 200-1500 eV with an APPLE-II type undulator. The commissioning procedure for the beamline optics is described in detail, especially the check of the focal position for the zero-th order and diffracted X rays.

  5. Back-scattering channel-cut high-resolution monochromator for inelastic x-ray scattering

    SciTech Connect (OSTI)

    Kushnir, V.I.; Abbamonte, P.M.; Macrander, A.T.; Schwoerer-Boehning, M.

    1997-08-01

    We report on a design and on some experimental results for the performance of a new high energy resolution monochromator. It is a large channel-cut Si crystal with a 197 mm separation between the two faces designed to operate in a near-backscattering regime. The device was tested as a second monochromator on Sector 3 of the Synchrotron Radiation Instrumentation Collaborative Access Team (SRI-CAT) at the Advanced Photon Source using the Si(777) reflection at a photon energy of 13.84 keV. The same monochromator can be used for other energies with reflections of the type (hhh). Special care has been taken to equalize the temperature of the two faces by employing a Peltier heat pump. A Si(111) double-crystal pre-monochromator designed to withstand the high heat load of the undulator radiation was used upstream on the beamline. The measured throughput efficiency of the Si(777) channel-cut monochromator was less ideal by a factor of 1.9. Dynamical diffraction theory was used to calculate the throughput of an ideally perfect crystal.

  6. Ultra-stable sub-meV monochromator for hard X-rays

    SciTech Connect (OSTI)

    Toellner, T. S.; Collins, J.; Goetze, K.; Hu, M. Y.; Preissner, C.; Trakhtenberg, E.; Yan, L.

    2015-07-17

    A high-resolution silicon monochromator suitable for 21.541 keV synchrotron radiation is presented that produces a bandwidth of 0.27 meV. The operating energy corresponds to a nuclear transition in 151Eu. The first-of-its-kind, fully cryogenic design achieves an energy-alignment stability of 0.017 meV r.m.s. per day, or a 100-fold improvement over other meV-monochromators, and can tolerate higher X-ray power loads than room-temperature designs of comparable resolution. This offers the potential for significantly more accurate measurements of lattice excitation energies using nuclear resonant vibrational spectroscopy if combined with accurate energy calibration using, for example, high-speed Doppler shifting. The design of the monochromator along with its performance and impact on transmitted beam properties are presented.

  7. Ultra-stable sub-meV monochromator for hard X-rays

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Toellner, T. S.; Collins, J.; Goetze, K.; Hu, M. Y.; Preissner, C.; Trakhtenberg, E.; Yan, L.

    2015-07-17

    A high-resolution silicon monochromator suitable for 21.541 keV synchrotron radiation is presented that produces a bandwidth of 0.27 meV. The operating energy corresponds to a nuclear transition in 151Eu. The first-of-its-kind, fully cryogenic design achieves an energy-alignment stability of 0.017 meV r.m.s. per day, or a 100-fold improvement over other meV-monochromators, and can tolerate higher X-ray power loads than room-temperature designs of comparable resolution. This offers the potential for significantly more accurate measurements of lattice excitation energies using nuclear resonant vibrational spectroscopy if combined with accurate energy calibration using, for example, high-speed Doppler shifting. The design of the monochromator alongmore » with its performance and impact on transmitted beam properties are presented.« less

  8. Inclined monochromator for high heat-load synchrotron x-ray radiation

    DOE Patents [OSTI]

    Khounsary, A.M.

    1994-02-15

    A double crystal monochromator is described including two identical, parallel crystals, each of which is cut such that the normal to the diffraction planes of interest makes an angle less than 90 degrees with the surface normal. Diffraction is symmetric, regardless of whether the crystals are symmetrically or asymmetrically cut, enabling operation of the monochromator with a fixed plane of diffraction. As a result of the inclination of the crystal surface, an incident beam has a footprint area which is elongated both vertically and horizontally when compared to that of the conventional monochromator, reducing the heat flux of the incident beam and enabling more efficient surface cooling. Because after inclination of the crystal only a fraction of thermal distortion lies in the diffraction plane, slope errors and the resultant misorientation of the diffracted beam are reduced. 11 figures.

  9. Inclined monochromator for high heat-load synchrotron x-ray radiation

    DOE Patents [OSTI]

    Khounsary, Ali M. (Lisle, IL)

    1994-01-01

    A double crystal monochromator including two identical, parallel crystals, each of which is cut such that the normal to the diffraction planes of interest makes an angle less than 90 degrees with the surface normal. Diffraction is symmetric, regardless of whether the crystals are symmetrically or asymmetrically cut, enabling operation of the monochromator with a fixed plane of diffraction. As a result of the inclination of the crystal surface, an incident beam has a footprint area which is elongated both vertically and horizontally when compared to that of the conventional monochromator, reducing the heat flux of the incident beam and enabling more efficient surface cooling. Because after inclination of the crystal only a fraction of thermal distortion lies in the diffraction plane, slope errors and the resultant misorientation of the diffracted beam are reduced.

  10. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  11. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  12. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  13. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamline 2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x

  14. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  15. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamline 2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x

  16. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamline 2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x

  17. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamline 2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x

  18. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  19. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  20. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  1. Beamline 2.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2.1 Print National Center for X-Ray Tomography (NCXT) Scientific discipline: Biology GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 400 - 1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 2048 x 2048 pixels Resolving power (E/ĢE) 500-700 Endstations X-ray microscope (XM-2) Characteristics Full-field soft x-ray transmission microscope Spatial resolution Zone-plate dependent Detectors Back-thinned 2048- x 2048-pixel

  2. High resolution monochromator for inelastic scattering studies of high energy phonons using undulator radiation at the advanced photon source

    SciTech Connect (OSTI)

    Macrander, A.T.; Schwoerer-Boehning, M.; Abbamonte, P.M.; Hu, M.

    1997-08-01

    A monochromator for use at 13.84 keV with a calculated bandpass of 5.2 meV was designed built, and tested. Tuning was performed by rotating the inner crystal of a pair of nested silicon channel-cut crystals. The inner crystal employs the (884) reflection, and the outer crystal employs a collimating asymmetric (422) reflection (dynamical asymmetry factor, b, equal to {minus}17.5). Tests were done with a double-crystal Si(111) pre-monochromator situated upstream of the high resolution monochromator and a Si(777) backscattering crystal situated downstream. For this optical arrangement an ideal value of 6.3 meV as calculated by x-ray dynamical diffraction theory applies for the FWHM of the convolution of the net monochromator reflectivity function with that of the Si(777) reflection. This calculated value is to be compared to the value of 7.1 meV measured by tuning the high resolution monochromator. Measured efficiencies were less than ideal by a factor of 3.2 to 4.9, where the larger flux reduction factors were found with higher positron storage ring currents.

  3. A dynamic focusing x-ray monochromator for a wiggler beam line at the SRS of the SERC Daresbury Laboratory

    SciTech Connect (OSTI)

    De Bruijn, D.; Van Zuylen, P. ); Kruizinga, G. , P.O. Box 93138, 2509 AC Den Haag State University of Utrecht, Sorbonnelaan 16, 3508 TB Utrecht )

    1992-01-01

    A Si(220) double-crystal monochromator for the energy range 10--30 keV is presented. It will be used for EXAFS as well as powder diffraction measurements. To determine the requirements for this monochromator we looked, apart from mean considerations, at the requirements dictated by EXAFS in transmission mode. For good data analyses the proper shape, amplitude, and location at the energy axis of each wiggle is required. Moreover it is essential to separate the wiggles from background and noise. For the latter a high flux through the sample is desirable, which can be achieved by horizontal focusing of the beam. For that we have chosen to bend the second crystal sagitally. The sagittal bending radius is adjustable between 50 and 0.8 m, because for different energies different sagittal radii are necessary to focus the beam on the sample. The mean meridional radius of the second crystal is fixed at 130 m, which is an optimization for 20 keV. The meridional radius of the first crystal can be tuned between 100 and 500 m. When this radius is set to 130 m the energy resolution is calculated to be 6, 3, and 35 eV for 10, 20, and 30 keV (for perfectly bent crystals). By changing the meridional radius of the first crystal, future users of this monochromator can make the trade off between resolution and intensity. Movement of the monochromator exit beam, during a scan, will occur due to the monochromator geometry, but is reduced as much as possible by using an asymmetrically cut second crystal, with an asymmetry angle of 2.5{degree}. The average exit beam movement of the monochromator for a 1-keV scan is 20 {mu}m. For 40% of the energy range (10--30 keV) the exit beam position remains within 10 {mu}m. For the second crystal no translation stage is used.

  4. Inductively coupled plasma-atomic emission spectroscopy: a computer controlled, scanning monochromator system for the rapid determination of the elements

    SciTech Connect (OSTI)

    Floyd, M.A.

    1980-03-01

    A computer controlled, scanning monochromator system specifically designed for the rapid, sequential determination of the elements is described. The monochromator is combined with an inductively coupled plasma excitation source so that elements at major, minor, trace, and ultratrace levels may be determined, in sequence, without changing experimental parameters other than the spectral line observed. A number of distinctive features not found in previously described versions are incorporated into the system here described. Performance characteristics of the entire system and several analytical applications are discussed.

  5. Temporal characterization of a time-compensated monochromator for high-efficiency selection of extreme-ultraviolet pulses generated by high-order harmonics

    SciTech Connect (OSTI)

    Poletto, L.; Villoresi, P.; Benedetti, E.; Ferrari, F.; Stagira, S.; Sansone, G.; Nisoli, M.

    2008-07-15

    Ultrafast extreme-ultraviolet pulses are spectrally selected by a time-delay-compensated grating monochromator. The intrinsic very short duration of the pulses is obtained by exploiting the high-order harmonic generation process. The temporal characterization of the harmonic pulses is obtained using a cross-correlation method: pulses as short as 8 fs are measured at the output of the monochromator in the case of the 23rd harmonic. This value is in agreement with the expected duration of such pulses, indicating that the influence of the monochromator is negligible. The photon flux has been measured with a calibrated photodiode, pointing out the good efficiency of the monochromator, derived by the exploitation for the two gratings of the conical diffraction mounting.

  6. A double crystal monochromator using tangentially bend crystals in combination with toroidal mirror focusing

    SciTech Connect (OSTI)

    Feng, Jun, Thompson,A.C.; Padmore,H.A.

    2000-02-24

    In collaboration with the Chemistry Department at the University of California at Berkeley, the ALS is building a beamline for structural determination in materials chemistry. The system will be used for single crystal x-ray diffraction on crystals that are too small or disordered for examination on laboratory systems, and typically will be used for crystals in the 5 - 20 micron regime. As some of the materials being designed are of the size of small proteins, phasing using direct methods is problematic, and so use of multiple wavelength anomalous dispersion techniques will be employed in many cases. The production of new compounds has been revolutionized in recent years with the development of combinatorial synthesis techniques, and a major b2048 to further advances in this field is access to rapid measurement of structural parameters. The specification of the beamline follows from these points. It must have a small focal spot to match closely the size of the crystals, high resolution for MAD techniques, and a high flux in the small focus. The strategy for satisfying these constraints is to us a system which is compact and which uses the minimum number of components. This is done in this case by using a pseudo channel cut crystal monochromator with tangentially bent crystals, in combination with a 1:1 focusing toroidal mirror. The toroidal mirror at 1:1 magnification has only very small aberrations, and from a 220 (h) by 25 (v) [micro] m FWHM source, an image of 220 by 45 [micro]m FWHM should be produced for a 3 mrad horizontal aperture for a full vertical aperture. This has already been achieved on an existing beamline. The crystal monochromator uses tangentially bent crystals in a concave - convex configuration to achieve matching of Bragg angles to the divergent source, while maintaining zero focusing power. A useful feature of this arrangement is that while there is an optimum crystal curvature for each energy that gives the expected Darwin width limited resolution, fixing the curvature gives approximately ideal resolution over typically 2 keV for the ALS bending magnet source. A further simplification is that the whole optical system will be inside the shield wall, with only a small pipe emerging from the shield wall to feed a standard commercial diffraction system. This means that the mirror will be at only 6.5 m from the source. This means that the toroidal mirror can be as short as 300 mm while collecting most of the vertical radiation fan. In addition, as the required tangential slope error is related to the angular size of the source, putting the mirror close reduces the slope error requirements substantially. These aspects together should result in a simple, low cost and very high performance system for small crystal, small molecule cr2048llography.

  7. Linear Accelerator

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Linear Accelerator (LINAC) The core of the LANSCE facility is one of the nation's most powerful proton linear accelerators or LINAC. The LINAC at LANSCE has served the nation since 1972, providing the beam current required by all the experimental areas that support NNSA-DP and other DOE missions. The LINAC's capability to reliably deliver beam current is the key to the LANSCE's ability to do research-and thus the key to meeting NNSA and DOE mission deliverables. The LANSCE Accelerator The LANSCE

  8. A comparison of absolute calibrations of a radiation thermometer based on a monochromator and a tunable source

    SciTech Connect (OSTI)

    Keawprasert, T.; Anhalt, K.; Taubert, D. R.; Sperling, A.; Schuster, M.; Nevas, S.

    2013-09-11

    An LP3 radiation thermometer was absolutely calibrated at a newly developed monochromator-based set-up and the TUneable Lasers in Photometry (TULIP) facility of PTB in the wavelength range from 400 nm to 1100 nm. At both facilities, the spectral radiation of the respective sources irradiates an integrating sphere, thus generating uniform radiance across its precision aperture. The spectral irradiance of the integrating sphere is determined via an effective area of a precision aperture and a Si trap detector, traceable to the primary cryogenic radiometer of PTB. Due to the limited output power from the monochromator, the absolute calibration was performed with the measurement uncertainty of 0.17 % (k= 1), while the respective uncertainty at the TULIP facility is 0.14 %. Calibration results obtained by the two facilities were compared in terms of spectral radiance responsivity, effective wavelength and integral responsivity. It was found that the measurement results in integral responsivity at the both facilities are in agreement within the expanded uncertainty (k= 2). To verify the calibration accuracy, the absolutely calibrated radiation thermometer was used to measure the thermodynamic freezing temperatures of the PTB gold fixed-point blackbody.

  9. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  10. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  11. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  12. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  13. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    6.1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  14. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamline 6.1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  15. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamline 6.1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  16. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    6.1.2 Beamline 6.1.2 Print Tuesday, 20 October 2009 08:41 Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700

  17. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  18. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1.2 Print Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE) 500-700 Endstations X-ray microscope (XM-1)

  19. Beamline 6.1.2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamline 6.1.2 Beamline 6.1.2 Print Tuesday, 20 October 2009 08:41 Center for X-Ray Optics Soft X-Ray Microscopy Scientific disciplines: Magnetism, spin dynamics, x-ray optics, environmental science, materials science GENERAL BEAMLINE INFORMATION Operational Yes Source characteristics Bend magnet Energy range 500-1300 eV Monochromator Zone-plate linear Measured flux (1.9 GeV, 400 mA) Images with 1000 x 1000 pixels, 1000 photons/pixel recorded in 3 s at 517 eV with 0.2% BW Resolving power (E/ΔE)

  20. Sagittal focusing Laue monochromator

    DOE Patents [OSTI]

    Zhong; Zhong (Stony Brook, NY), Hanson; Jonathan (Wading River, NY), Hastings; Jerome (Stanford, CA), Kao; Chi-Chang (Setauket, NY), Lenhard; Anthony (Medford, NY), Siddons; David Peter (Cutchogue, NY), Zhong; Hui (Coram, NY)

    2009-03-24

    An x-ray focusing device generally includes a slide pivotable about a pivot point defined at a forward end thereof, a rail unit fixed with respect to the pivotable slide, a forward crystal for focusing x-rays disposed at the forward end of the pivotable slide and a rearward crystal for focusing x-rays movably coupled to the pivotable slide and the fixed rail unit at a distance rearward from the forward crystal. The forward and rearward crystals define reciprocal angles of incidence with respect to the pivot point, wherein pivoting of the slide about the pivot point changes the incidence angles of the forward and rearward crystals while simultaneously changing the distance between the forward and rearward crystals.

  1. A laboratory-based hard x-ray monochromator for high-resolution x-ray emission spectroscopy and x-ray absorption near edge structure measurements

    SciTech Connect (OSTI)

    Seidler, G. T. Mortensen, D. R.; Remesnik, A. J.; Pacold, J. I.; Ball, N. A.; Barry, N.; Styczinski, M.; Hoidn, O. R.

    2014-11-15

    We report the development of a laboratory-based Rowland-circle monochromator that incorporates a low power x-ray (bremsstrahlung) tube source, a spherically bent crystal analyzer, and an energy-resolving solid-state detector. This relatively inexpensive, introductory level instrument achieves 1-eV energy resolution for photon energies of ?5 keV to ?10 keV while also demonstrating a net efficiency previously seen only in laboratory monochromators having much coarser energy resolution. Despite the use of only a compact, air-cooled 10 W x-ray tube, we find count rates for nonresonant x-ray emission spectroscopy comparable to those achieved at monochromatized spectroscopy beamlines at synchrotron light sources. For x-ray absorption near edge structure, the monochromatized flux is small (due to the use of a low-powered x-ray generator) but still useful for routine transmission-mode studies of concentrated samples. These results indicate that upgrading to a standard commercial high-power line-focused x-ray tube or rotating anode x-ray generator would result in monochromatized fluxes of order 10{sup 6}10{sup 7} photons/s with no loss in energy resolution. This work establishes core technical capabilities for a rejuvenation of laboratory-based hard x-ray spectroscopies that could have special relevance for contemporary research on catalytic or electrical energy storage systems using transition-metal, lanthanide, or noble-metal active species.

  2. Linear phase compressive filter

    DOE Patents [OSTI]

    McEwan, T.E.

    1995-06-06

    A phase linear filter for soliton suppression is in the form of a laddered series of stages of non-commensurate low pass filters with each low pass filter having a series coupled inductance (L) and a reverse biased, voltage dependent varactor diode, to ground which acts as a variable capacitance (C). L and C values are set to levels which correspond to a linear or conventional phase linear filter. Inductance is mapped directly from that of an equivalent nonlinear transmission line and capacitance is mapped from the linear case using a large signal equivalent of a nonlinear transmission line. 2 figs.

  3. Linear phase compressive filter

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1995-01-01

    A phase linear filter for soliton suppression is in the form of a laddered series of stages of non-commensurate low pass filters with each low pass filter having a series coupled inductance (L) and a reverse biased, voltage dependent varactor diode, to ground which acts as a variable capacitance (C). L and C values are set to levels which correspond to a linear or conventional phase linear filter. Inductance is mapped directly from that of an equivalent nonlinear transmission line and capacitance is mapped from the linear case using a large signal equivalent of a nonlinear transmission line.

  4. Fault tolerant linear actuator

    DOE Patents [OSTI]

    Tesar, Delbert

    2004-09-14

    In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.

  5. Linearly polarized fiber amplifier

    DOE Patents [OSTI]

    Kliner, Dahv A.; Koplow, Jeffery P.

    2004-11-30

    Optically pumped rare-earth-doped polarizing fibers exhibit significantly higher gain for one linear polarization state than for the orthogonal state. Such a fiber can be used to construct a single-polarization fiber laser, amplifier, or amplified-spontaneous-emission (ASE) source without the need for additional optical components to obtain stable, linearly polarized operation.

  6. Linear induction accelerator

    SciTech Connect (OSTI)

    Bosamykin, V.S.; Pavlovskiy, A.I.

    1984-03-01

    A linear induction accelerator of charged particles, containing inductors and an acceleration circuit, characterized by the fact that, for the purpose of increasing the power of the accelerator, each inductor is made in the form of a toroidal line with distributed parameters, from one end of which in the gap of the line a ring commutator is included, and from the other end of the ine a resistor is hooked up, is described.

  7. Linear induction accelerator

    DOE Patents [OSTI]

    Buttram, M.T.; Ginn, J.W.

    1988-06-21

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  8. Combustion powered linear actuator

    DOE Patents [OSTI]

    Fischer, Gary J. (Albuquerque, NM)

    2007-09-04

    The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

  9. Non Linear Conjugate Gradient

    Energy Science and Technology Software Center (OSTI)

    2006-11-17

    Software that simulates and inverts electromagnetic field data for subsurface electrical properties (electrical conductivity) of geological media. The software treats data produced by a time harmonic source field excitation arising from the following antenna geometery: loops and grounded bipoles, as well as point electric and magnetic dioples. The inversion process is carried out using a non-linear conjugate gradient optimization scheme, which minimizes the misfit between field data and model data using a least squares criteria.more »The software is an upgrade from the code NLCGCS_MP ver 1.0. The upgrade includes the following components: Incorporation of new 1 D field sourcing routines to more accurately simulate the 3D electromagnetic field for arbitrary geologic& media, treatment for generalized finite length transmitting antenna geometry (antennas with vertical and horizontal component directions). In addition, the software has been upgraded to treat transverse anisotropy in electrical conductivity.« less

  10. Positrons for linear colliders

    SciTech Connect (OSTI)

    Ecklund, S.

    1987-11-01

    The requirements of a positron source for a linear collider are briefly reviewed, followed by methods of positron production and production of photons by electromagnetic cascade showers. Cross sections for the electromagnetic cascade shower processes of positron-electron pair production and Compton scattering are compared. A program used for Monte Carlo analysis of electromagnetic cascades is briefly discussed, and positron distributions obtained from several runs of the program are discussed. Photons from synchrotron radiation and from channeling are also mentioned briefly, as well as positron collection, transverse focusing techniques, and longitudinal capture. Computer ray tracing is then briefly discussed, followed by space-charge effects and thermal heating and stress due to showers. (LEW)

  11. History of Proton Linear Accelerators

    DOE R&D Accomplishments [OSTI]

    Alvarez, L. W.

    1987-01-01

    Some personal recollections are presented that relate to the author`s experience developing linear accelerators, particularly for protons. (LEW)

  12. New Zone Plate for Soft X-Ray Microscopy at 15-nm Spatial Resolution

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    contrast (modulation) between light and dark features of the pattern was also remarkably good. The calculated modulation transfer functions of the microscope with an older micro...

  13. Linear induction pump

    DOE Patents [OSTI]

    Meisner, John W.; Moore, Robert M.; Bienvenue, Louis L.

    1985-03-19

    Electromagnetic linear induction pump for liquid metal which includes a unitary pump duct. The duct comprises two substantially flat parallel spaced-apart wall members, one being located above the other and two parallel opposing side members interconnecting the wall members. Located within the duct are a plurality of web members interconnecting the wall members and extending parallel to the side members whereby the wall members, side members and web members define a plurality of fluid passageways, each of the fluid passageways having substantially the same cross-sectional flow area. Attached to an outer surface of each side member is an electrically conductive end bar for the passage of an induced current therethrough. A multi-phase, electrical stator is located adjacent each of the wall members. The duct, stators, and end bars are enclosed in a housing which is provided with an inlet and outlet in fluid communication with opposite ends of the fluid passageways in the pump duct. In accordance with a preferred embodiment, the inlet and outlet includes a transition means which provides for a transition from a round cross-sectional flow path to a substantially rectangular cross-sectional flow path defined by the pump duct.

  14. Winding for linear pump

    DOE Patents [OSTI]

    Kliman, Gerald B. (Schenectady, NY); Brynsvold, Glen V. (San Jose, CA); Jahns, Thomas M. (Schenectady, NY)

    1989-01-01

    A winding and method of winding for a submersible linear pump for pumping liquid sodium is disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet.

  15. Winding for linear pump

    DOE Patents [OSTI]

    Kliman, G.B.; Brynsvold, G.V.; Jahns, T.M.

    1989-08-22

    A winding and method of winding for a submersible linear pump for pumping liquid sodium are disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet. 4 figs.

  16. Berkeley Proton Linear Accelerator

    DOE R&D Accomplishments [OSTI]

    Alvarez, L. W.; Bradner, H.; Franck, J.; Gordon, H.; Gow, J. D.; Marshall, L. C.; Oppenheimer, F. F.; Panofsky, W. K. H.; Richman, C.; Woodyard, J. R.

    1953-10-13

    A linear accelerator, which increases the energy of protons from a 4 Mev Van de Graaff injector, to a final energy of 31.5 Mev, has been constructed. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio-frequency power of about 2.2 x 10{sup 6} watts peak at 202.5 mc. Acceleration is made possible by the introduction of 46 axial "drift tubes" into the cavity, which is designed such that the particles traverse the distance between the centers of successive tubes in one cycle of the r.f. power. The protons are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high powered oscillators fed from a pulse generator of the artificial transmission line type.

  17. Linear Fresnel | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    DOE funds solar research and development (R&D) in linear Fresnel systems as one of four CSP technologies aiming to meet the goals of the SunShot Initiative. Linear Fresnel systems, which are a type of linear concentrator, are active in Germany, Spain, Australia, India, and the United States. The SunShot Initiative funds R&D on linear Fresnel systems and related aspects within the industry, national laboratories and universities to meet the SunShot goals. An extensive set of core

  18. Acoustic emission linear pulse holography

    DOE Patents [OSTI]

    Collins, H.D.; Busse, L.J.; Lemon, D.K.

    1983-10-25

    This device relates to the concept of and means for performing Acoustic Emission Linear Pulse Holography, which combines the advantages of linear holographic imaging and Acoustic Emission into a single non-destructive inspection system. This unique system produces a chronological, linear holographic image of a flaw by utilizing the acoustic energy emitted during crack growth. The innovation is the concept of utilizing the crack-generated acoustic emission energy to generate a chronological series of images of a growing crack by applying linear, pulse holographic processing to the acoustic emission data. The process is implemented by placing on a structure an array of piezoelectric sensors (typically 16 or 32 of them) near the defect location. A reference sensor is placed between the defect and the array.

  19. Linear Accelerator | Advanced Photon Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Linear Accelerator Producing brilliant x-ray beams at the APS begins with electrons emitted from a cathode heated to 1100 C. The electrons are accelerated by high-voltage...

  20. Belos Block Linear Solvers Package

    Energy Science and Technology Software Center (OSTI)

    2004-03-01

    Belos is an extensible and interoperable framework for large-scale, iterative methods for solving systems of linear equations with multiple right-hand sides. The motivation for this framework is to provide a generic interface to a collection of algorithms for solving large-scale linear systems. Belos is interoperable because both the matrix and vectors are considered to be opaque objects--only knowledge of the matrix and vectors via elementary operations is necessary. An implementation of Balos is accomplished viamore » the use of interfaces. One of the goals of Belos is to allow the user flexibility in specifying the data representation for the matrix and vectors and so leverage any existing software investment. The algorithms that will be included in package are Krylov-based linear solvers, like Block GMRES (Generalized Minimal RESidual) and Block CG (Conjugate-Gradient).« less

  1. Linear electric field mass spectrometry

    DOE Patents [OSTI]

    McComas, David J. (Los Alamos, NM); Nordholt, Jane E. (Los Alamos, NM)

    1992-01-01

    A mass spectrometer and methods for mass spectrometry. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field.

  2. Linear electric field mass spectrometry

    DOE Patents [OSTI]

    McComas, D.J.; Nordholt, J.E.

    1992-12-01

    A mass spectrometer and methods for mass spectrometry are described. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field. 8 figs.

  3. Segmented rail linear induction motor

    DOE Patents [OSTI]

    Cowan, M. Jr.; Marder, B.M.

    1996-09-03

    A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces. 6 figs.

  4. Cast dielectric composite linear accelerator

    DOE Patents [OSTI]

    Sanders, David M. (Livermore, CA); Sampayan, Stephen (Manteca, CA); Slenes, Kirk (Albuquerque, NM); Stoller, H. M. (Albuquerque, NM)

    2009-11-10

    A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

  5. Precision linear ramp function generator

    DOE Patents [OSTI]

    Jatko, W. Bruce (Knoxville, TN); McNeilly, David R. (Maryville, TN); Thacker, Louis H. (Knoxville, TN)

    1986-01-01

    A ramp function generator is provided which produces a precise linear ramp unction which is repeatable and highly stable. A derivative feedback loop is used to stabilize the output of an integrator in the forward loop and control the ramp rate. The ramp may be started from a selected baseline voltage level and the desired ramp rate is selected by applying an appropriate constant voltage to the input of the integrator.

  6. Precision linear ramp function generator

    DOE Patents [OSTI]

    Jatko, W.B.; McNeilly, D.R.; Thacker, L.H.

    1984-08-01

    A ramp function generator is provided which produces a precise linear ramp function which is repeatable and highly stable. A derivative feedback loop is used to stabilize the output of an integrator in the forward loop and control the ramp rate. The ramp may be started from a selected baseline voltage level and the desired ramp rate is selected by applying an appropriate constant voltage to the input of the integrator.

  7. Segmented rail linear induction motor

    DOE Patents [OSTI]

    Cowan, Jr., Maynard (1107 Stagecoach Rd. SE., Albuquerque, NM 87123); Marder, Barry M. (1412 Pinnacle View Dr. NE., Albuquerque, NM 87123)

    1996-01-01

    A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces.

  8. Linear Thermite Charge - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Linear Thermite Charge Battelle Memorial Institute Contact BMI About This Technology Publications: PDF Document Publication Linear Thermite Charge Picture (40 KB) PDF Document Publication Linear Thermite Charge Patent (207 KB) Technology Marketing Summary The Linear Thermite Charge (LTC) is designed to rapidly cut through concrete and steel structural components by using extremely high temperature thermite reactions jetted through a linear nozzle. Description Broadly, the invention provides for

  9. Acoustic emission linear pulse holography

    DOE Patents [OSTI]

    Collins, H. Dale (Richland, WA); Busse, Lawrence J. (Richland, WA); Lemon, Douglas K. (West Richland, WA)

    1985-01-01

    Defects in a structure are imaged as they propagate, using their emitted acoustic energy as a monitored source. Short bursts of acoustic energy propagate through the structure to a discrete element receiver array. A reference timing transducer located between the array and the inspection zone initiates a series of time-of-flight measurements. A resulting series of time-of-flight measurements are then treated as aperture data and are transferred to a computer for reconstruction of a synthetic linear holographic image. The images can be displayed and stored as a record of defect growth.

  10. PC Basic Linear Algebra Subroutines

    Energy Science and Technology Software Center (OSTI)

    1992-03-09

    PC-BLAS is a highly optimized version of the Basic Linear Algebra Subprograms (BLAS), a standardized set of thirty-eight routines that perform low-level operations on vectors of numbers in single and double-precision real and complex arithmetic. Routines are included to find the index of the largest component of a vector, apply a Givens or modified Givens rotation, multiply a vector by a constant, determine the Euclidean length, perform a dot product, swap and copy vectors, andmore » find the norm of a vector. The BLAS have been carefully written to minimize numerical problems such as loss of precision and underflow and are designed so that the computation is independent of the interface with the calling program. This independence is achieved through judicious use of Assembly language macros. Interfaces are provided for Lahey Fortran 77, Microsoft Fortran 77, and Ryan-McFarland IBM Professional Fortran.« less

  11. Linear induction accelerator parameter options

    SciTech Connect (OSTI)

    Birx, D.L.; Caporaso, G.J.; Reginato, L.L.

    1986-04-21

    The principal undertaking of the Beam Research Program over the past decade has been the investigation of propagating intense self-focused beams. Recently, the major activity of the program has shifted toward the investigation of converting high quality electron beams directly to laser radiation. During the early years of the program, accelerator development was directed toward the generation of very high current (>10 kA), high energy beams (>50 MeV). In its new mission, the program has shifted the emphasis toward the production of lower current beams (>3 kA) with high brightness (>10/sup 6/ A/(rad-cm)/sup 2/) at very high average power levels. In efforts to produce these intense beams, the state of the art of linear induction accelerators (LIA) has been advanced to the point of satisfying not only the current requirements but also future national needs.

  12. Reticle stage based linear dosimeter

    DOE Patents [OSTI]

    Berger, Kurt W.

    2007-03-27

    A detector to measure EUV intensity employs a linear array of photodiodes. The detector is particularly suited for photolithography systems that includes: (i) a ringfield camera; (ii) a source of radiation; (iii) a condenser for processing radiation from the source of radiation to produce a ringfield illumination field for illuminating a mask; (iv) a reticle that is positioned at the ringfield camera's object plane and from which a reticle image in the form of an intensity profile is reflected into the entrance pupil of the ringfield camera, wherein the reticle moves in a direction that is transverse to the length of the ringfield illumination field that illuminates the reticle; (v) detector for measuring the entire intensity along the length of the ringfield illumination field that is projected onto the reticle; and (vi) a wafer onto which the reticle imaged is projected from the ringfield camera.

  13. Reticle stage based linear dosimeter

    DOE Patents [OSTI]

    Berger, Kurt W.

    2005-06-14

    A detector to measure EUV intensity employs a linear array of photodiodes. The detector is particularly suited for photolithography systems that includes: (i) a ringfield camera; (ii) a source of radiation; (iii) a condenser for processing radiation from the source of radiation to produce a ringfield illumination field for illuminating a mask; (iv) a reticle that is positioned at the ringfield camera's object plane and from which a reticle image in the form of an intensity profile is reflected into the entrance pupil of the ringfield camera, wherein the reticle moves in a direction that is transverse to the length of the ringfield illumination field that illuminates the reticle; (v) detector for measuring the entire intensity along the length of the ringfield illumination field that is projected onto the reticle; and (vi) a wafer onto which the reticle imaged is projected from the ringfield camera.

  14. High Performance Preconditioners and Linear Solvers

    Energy Science and Technology Software Center (OSTI)

    2006-07-27

    Hypre is a software library focused on the solution of large, sparse linear systems of equations on massively parallel computers.

  15. International Workshop on Linear Colliders 2010

    ScienceCinema (OSTI)

    None

    2011-10-06

    IWLC2010 International Workshop on Linear Colliders 2010ECFA-CLIC-ILC joint meeting: Monday 18 October - Friday 22 October 2010Venue: CERN and CICG (International Conference Centre Geneva, Switzerland) This year, the International Workshop on Linear Colliders organized by the European Committee for Future Accelerators (ECFA) will study the physics, detectors and accelerator complex of a linear collider covering both CLIC and ILC options.Contact Workshop Secretariat  IWLC2010 is hosted by CERN

  16. International Workshop on Linear Colliders 2010

    ScienceCinema (OSTI)

    None

    2011-10-06

    IWLC2010 International Workshop on Linear Colliders 2010ECFA-CLIC-ILC joint meeting: Monday 18 October - Friday 22 October 2010Venue: CERN and CICG (International Conference Centre Geneva, Switzerland)This year, the International Workshop on Linear Colliders organized by the European Committee for Future Accelerators (ECFA) will study the physics, detectors and accelerator complex of a linear collider covering both CLIC and ILC options.Contact Workshop SecretariatIWLC2010 is hostedby CERN

  17. Ultra-high vacuum photoelectron linear accelerator

    DOE Patents [OSTI]

    Yu, David U.L.; Luo, Yan

    2013-07-16

    An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.

  18. International Linear Collider Technical Design Report - Volume...

    Office of Scientific and Technical Information (OSTI)

    Linear Collider Technical Design Report - Volume 2: Physics Baer, Howard; Barklow, Tim; Fujii, Keisuke; Gao, Yuanning; Hoang, Andre; Kanemura, Shinya; List, Jenny; Logan, Heather...

  19. International Linear Collider Technical Design Report - Volume...

    Office of Scientific and Technical Information (OSTI)

    Design Report - Volume 2: Physics Citation Details In-Document Search Title: International Linear Collider Technical Design Report - Volume 2: Physics You are accessing a ...

  20. Non-Linear Seismic Soil Structure Interaction (SSI) Method for...

    Office of Environmental Management (EM)

    Structure Interaction (SSI) Method for Developing Non-Linear Seismic SSI Analysis Techniques Non-Linear Seismic Soil Structure Interaction (SSI) Method for Developing Non-Linear...

  1. Two-axis sagittal focusing monochromator

    DOE Patents [OSTI]

    Haas, Edwin G; Stelmach, Christopher; Zhong, Zhong

    2014-05-13

    An x-ray focusing device and method for adjustably focusing x-rays in two orthogonal directions simultaneously. The device and method can be operated remotely using two pairs of orthogonal benders mounted on a rigid, open frame such that x-rays may pass through the opening in the frame. The added x-ray flux allows significantly higher brightness from the same x-ray source.

  2. Multiple wavelength X-ray monochromators

    DOE Patents [OSTI]

    Steinmeyer, P.A.

    1992-11-17

    An improved apparatus and method is provided for separating input x-ray radiation containing first and second x-ray wavelengths into spatially separate first and second output radiation which contain the first and second x-ray wavelengths, respectively. The apparatus includes a crystalline diffractor which includes a first set of parallel crystal planes, where each of the planes is spaced a predetermined first distance from one another. The crystalline diffractor also includes a second set of parallel crystal planes inclined at an angle with respect to the first set of crystal planes where each of the planes of the second set of parallel crystal planes is spaced a predetermined second distance from one another. In one embodiment, the crystalline diffractor is comprised of a single crystal. In a second embodiment, the crystalline diffractor is comprised of a stack of two crystals. In a third embodiment, the crystalline diffractor includes a single crystal that is bent for focusing the separate first and second output x-ray radiation wavelengths into separate focal points. 3 figs.

  3. Multiple wavelength X-ray monochromators

    DOE Patents [OSTI]

    Steinmeyer, Peter A. (Arvada, CO)

    1992-11-17

    An improved apparatus and method is provided for separating input x-ray radiation containing first and second x-ray wavelengths into spatially separate first and second output radiation which contain the first and second x-ray wavelengths, respectively. The apparatus includes a crystalline diffractor which includes a first set of parallel crystal planes, where each of the planes is spaced a predetermined first distance from one another. The crystalline diffractor also includes a second set of parallel crystal planes inclined at an angle with respect to the first set of crystal planes where each of the planes of the second set of parallel crystal planes is spaced a predetermined second distance from one another. In one embodiment, the crystalline diffractor is comprised of a single crystal. In a second embodiment, the crystalline diffractor is comprised of a stack of two crystals. In a third embodiment, the crystalline diffractor includes a single crystal that is bent for focussing the separate first and second output x-ray radiation wavelengths into separate focal points.

  4. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M. (Santa Fe, NM)

    1992-01-01

    Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

  5. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29

    Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

  6. Optically isolated signal coupler with linear response

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1994-01-01

    An optocoupler for isolating electrical signals that translates an electrical input signal linearly to an electrical output signal. The optocoupler comprises a light emitter, a light receiver, and a light transmitting medium. The light emitter, preferably a blue, silicon carbide LED, is of the type that provides linear, electro-optical conversion of electrical signals within a narrow wavelength range. Correspondingly, the light receiver, which converts light signals to electrical signals and is preferably a cadmium sulfide photoconductor, is linearly responsive to light signals within substantially the same wavelength range as the blue LED.

  7. Beamline 9.0.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    9.0.1 Beamline 9.0.1 Print Tuesday, 20 October 2009 08:57 Diffraction Microscopy Scientific disciplines: Applied science, biology, polymers, soft materials. Endstations: Serial crystallography Diffractive imaging Nanosurveyor GENERAL BEAMLINE INFORMATION Operational Yes. Source characteristics 10-cm period undulator (U10) Energy range 500-1500 eV Monochromator Either none or an off-axis zone-plate monochromator that will provide a focused beam with bandwidth of about 0.1% Calculated flux (1.9

  8. Beamline 9.0.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0.1 Print Diffraction Microscopy Scientific disciplines: Applied science, biology, polymers, soft materials. Endstations: Serial crystallography Diffractive imaging Nanosurveyor GENERAL BEAMLINE INFORMATION Operational Yes. Source characteristics 10-cm period undulator (U10) Energy range 500-1500 eV Monochromator Either none or an off-axis zone-plate monochromator that will provide a focused beam with bandwidth of about 0.1% Calculated flux (1.9 GeV, 400 mA) 2.8 x 1015 photons/s/1%BW/central

  9. Beamline 9.0.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    9.0.1 Print Diffraction Microscopy Scientific disciplines: Applied science, biology, polymers, soft materials. Endstations: Serial crystallography Diffractive imaging Nanosurveyor GENERAL BEAMLINE INFORMATION Operational Yes. Source characteristics 10-cm period undulator (U10) Energy range 500-1500 eV Monochromator Either none or an off-axis zone-plate monochromator that will provide a focused beam with bandwidth of about 0.1% Calculated flux (1.9 GeV, 400 mA) 2.8 x 1015 photons/s/1%BW/central

  10. Beamline 9.0.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1 Print Diffraction Microscopy Scientific disciplines: Applied science, biology, polymers, soft materials. Endstations: Serial crystallography Diffractive imaging Nanosurveyor GENERAL BEAMLINE INFORMATION Operational Yes. Source characteristics 10-cm period undulator (U10) Energy range 500-1500 eV Monochromator Either none or an off-axis zone-plate monochromator that will provide a focused beam with bandwidth of about 0.1% Calculated flux (1.9 GeV, 400 mA) 2.8 x 1015 photons/s/1%BW/central cone

  11. Beamline 9.0.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    9.0.1 Beamline 9.0.1 Print Tuesday, 20 October 2009 08:57 Diffraction Microscopy Scientific disciplines: Applied science, biology, polymers, soft materials. Endstations: Serial crystallography Diffractive imaging Nanosurveyor GENERAL BEAMLINE INFORMATION Operational Yes. Source characteristics 10-cm period undulator (U10) Energy range 500-1500 eV Monochromator Either none or an off-axis zone-plate monochromator that will provide a focused beam with bandwidth of about 0.1% Calculated flux (1.9

  12. Beamline 9.0.1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0.1 Beamline 9.0.1 Print Tuesday, 20 October 2009 08:57 Diffraction Microscopy Scientific disciplines: Applied science, biology, polymers, soft materials. Endstations: Serial crystallography Diffractive imaging Nanosurveyor GENERAL BEAMLINE INFORMATION Operational Yes. Source characteristics 10-cm period undulator (U10) Energy range 500-1500 eV Monochromator Either none or an off-axis zone-plate monochromator that will provide a focused beam with bandwidth of about 0.1% Calculated flux (1.9 GeV,

  13. Dual-range linearized transimpedance amplifier system

    DOE Patents [OSTI]

    Wessendorf, Kurt O. (Albuquerque, NM)

    2010-11-02

    A transimpedance amplifier system is disclosed which simultaneously generates a low-gain output signal and a high-gain output signal from an input current signal using a single transimpedance amplifier having two different feedback loops with different amplification factors to generate two different output voltage signals. One of the feedback loops includes a resistor, and the other feedback loop includes another resistor in series with one or more diodes. The transimpedance amplifier system includes a signal linearizer to linearize one or both of the low- and high-gain output signals by scaling and adding the two output voltage signals from the transimpedance amplifier. The signal linearizer can be formed either as an analog device using one or two summing amplifiers, or alternately can be formed as a digital device using two analog-to-digital converters and a digital signal processor (e.g. a microprocessor or a computer).

  14. Linear transformer driver for pulse generation

    DOE Patents [OSTI]

    Kim, Alexander A; Mazarakis, Michael G; Sinebryukhov, Vadim A; Volkov, Sergey N; Kondratiev, Sergey S; Alexeenko, Vitaly M; Bayol, Frederic; Demol, Gauthier; Stygar, William A

    2015-04-07

    A linear transformer driver includes at least one ferrite ring positioned to accept a load. The linear transformer driver also includes a first power delivery module that includes a first charge storage devices and a first switch. The first power delivery module sends a first energy in the form of a first pulse to the load. The linear transformer driver also includes a second power delivery module including a second charge storage device and a second switch. The second power delivery module sends a second energy in the form of a second pulse to the load. The second pulse has a frequency that is approximately three times the frequency of the first pulse. The at least one ferrite ring is positioned to force the first pulse and the second pulse to the load by temporarily isolating the first pulse and the second pulse from an electrical ground.

  15. Linear and angular retroreflecting interferometric alignment target

    DOE Patents [OSTI]

    Maxey, L. Curtis

    2001-01-01

    The present invention provides a method and apparatus for measuring both the linear displacement and angular displacement of an object using a linear interferometer system and an optical target comprising a lens, a reflective surface and a retroreflector. The lens, reflecting surface and retroreflector are specifically aligned and fixed in optical connection with one another, creating a single optical target which moves as a unit that provides multi-axis displacement information for the object with which it is associated. This displacement information is useful in many applications including machine tool control systems and laser tracker systems, among others.

  16. Beamstrahlung spectra in next generation linear colliders

    SciTech Connect (OSTI)

    Barklow, T.; Chen, P. ); Kozanecki, W. )

    1992-04-01

    For the next generation of linear colliders, the energy loss due to beamstrahlung during the collision of the e{sup +}e{sup {minus}} beams is expected to substantially influence the effective center-of-mass energy distribution of the colliding particles. In this paper, we first derive analytical formulae for the electron and photon energy spectra under multiple beamstrahlung processes, and for the e{sup +}e{sup {minus}} and {gamma}{gamma} differential luminosities. We then apply our formulation to various classes of 500 GeV e{sup +}e{sup {minus}} linear collider designs currently under study.

  17. Linear Transformation Method for Multinuclide Decay Calculation

    SciTech Connect (OSTI)

    Ding Yuan

    2010-12-29

    A linear transformation method for generic multinuclide decay calculations is presented together with its properties and implications. The method takes advantage of the linear form of the decay solution N(t) = F(t)N{sub 0}, where N(t) is a column vector that represents the numbers of atoms of the radioactive nuclides in the decay chain, N{sub 0} is the initial value vector of N(t), and F(t) is a lower triangular matrix whose time-dependent elements are independent of the initial values of the system.

  18. Linear and non-linear forced response of a conical, ducted, laminar premixed flame

    SciTech Connect (OSTI)

    Karimi, Nader; Brear, Michael J.; Jin, Seong-Ho; Monty, Jason P. [Department of Mechanical Engineering, University of Melbourne, Parkville, 3010 Vic. (Australia)

    2009-11-15

    This paper presents an experimental study on the dynamics of a ducted, conical, laminar premixed flame subjected to acoustic excitation of varying amplitudes. The flame transfer function is measured over a range of forcing frequencies and equivalence ratios. In keeping with previous works, the measured flame transfer function is in good agreement with that predicted by linear kinematic theory at low amplitudes of acoustic velocity excitation. However, a systematic departure from linear behaviour is observed as the amplitude of the velocity forcing upstream of the flame increases. This non-linearity is mostly in the phase of the transfer function and manifests itself as a roughly constant phase at high forcing amplitude. Nonetheless, as predicted by non-linear kinematic arguments, the response always remains close to linear at low forcing frequencies, regardless of the forcing amplitude. The origin of this phase behaviour is then sought through optical data post-processing. (author)

  19. Finite Element Interface to Linear Solvers

    Energy Science and Technology Software Center (OSTI)

    2005-03-18

    Sparse systems of linear equations arise in many engineering applications, including finite elements, finite volumes, and others. The solution of linear systems is often the most computationally intensive portion of the application. Depending on the complexity of problems addressed by the application, there may be no single solver capable of solving all of the linear systems that arise. This motivates the desire to switch an application from one solver librwy to another, depending on themoreproblem being solved. The interfaces provided by solver libraries differ greatly, making it difficult to switch an application code from one library to another. The amount of library-specific code in an application Can be greatly reduced by having an abstraction layer between solver libraries and the application, putting a common "face" on various solver libraries. One such abstraction layer is the Finite Element Interface to Linear Solvers (EEl), which has seen significant use by finite element applications at Sandia National Laboratories and Lawrence Livermore National Laboratory.less

  20. A microcomputer-controlled linear heater

    SciTech Connect (OSTI)

    Schuck, V.; Rahimi, S. )

    1991-10-01

    In this note the circuits and principles of operation of a relatively simple and inexpensive linear temperature ramp generator are described. The upper-temperature limit and the heating rate are controlled by an Apple II microcomputer. The temperature versus time is displayed on the screen and may be plotted by an {ital x}-{ital y} plotter.

  1. Notes on beam dynamics in linear accelerators

    SciTech Connect (OSTI)

    Gluckstern, R.L.

    1980-09-01

    A collection of notes, on various aspects of beam dynamics in linear accelerators, which were produced by the author during five years (1975 to 1980) of consultation for the LASL Accelerator Technology (AT) Division and Medium-Energy Physics (MP) Division is presented.

  2. Producing Linear Alpha Olefins From Biomass - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Producing Linear Alpha Olefins From Biomass Great Lakes Bioenergy Research Center Contact GLBRC About This Technology Technology Marketing Summary Linear alpha olefins (LAOs) are...

  3. A Linear Theory of Microwave Instability in Electron Storage...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: A Linear Theory of Microwave Instability in Electron Storage Rings Citation Details In-Document Search Title: A Linear Theory of Microwave Instability in Electron...

  4. 2010 Annual Planning Summary for Stanford Linear Accelerator...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Stanford Linear Accelerator Center Site Office (SLAC) 2010 Annual Planning Summary for Stanford Linear Accelerator Center Site Office (SLAC) Annual Planning Summaries briefly...

  5. Cascaded emission of linearly polarized single photons from positioned...

    Office of Scientific and Technical Information (OSTI)

    Cascaded emission of linearly polarized single photons from positioned InPGaInP quantum dots Citation Details In-Document Search Title: Cascaded emission of linearly polarized ...

  6. MHK Technologies/Ocean Current Linear Turbine | Open Energy Informatio...

    Open Energy Info (EERE)

    Current Linear Turbine < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Ocean Current Linear Turbine.jpg Technology Profile Primary...

  7. Updates to the International Linear Collider Damping Rings Baseline...

    Office of Scientific and Technical Information (OSTI)

    Updates to the International Linear Collider Damping Rings Baseline Design Citation Details In-Document Search Title: Updates to the International Linear Collider Damping Rings...

  8. Toward portable programming of numerical linear algebra on manycore...

    Office of Scientific and Technical Information (OSTI)

    Toward portable programming of numerical linear algebra on manycore nodes. Citation Details In-Document Search Title: Toward portable programming of numerical linear algebra on ...

  9. Top quark anomalous couplings at the International Linear Collider...

    Office of Scientific and Technical Information (OSTI)

    Top quark anomalous couplings at the International Linear Collider Citation Details In-Document Search Title: Top quark anomalous couplings at the International Linear Collider ...

  10. Ubiquity of linear resistivity at intermediate temperature in...

    Office of Scientific and Technical Information (OSTI)

    Ubiquity of linear resistivity at intermediate temperature in bad metals Prev Next Title: Ubiquity of linear resistivity at intermediate temperature in bad metals Authors: ...

  11. Ubiquity of linear resistivity at intermediate temperature in...

    Office of Scientific and Technical Information (OSTI)

    Ubiquity of linear resistivity at intermediate temperature in bad metals Citation Details In-Document Search Title: Ubiquity of linear resistivity at intermediate temperature in ...

  12. High Impact Technology HQ - Results - LED Troffer, Cove (linear...

    Energy Savers [EERE]

    HQ - Results - LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory High Impact Technology HQ - Results - LED Troffer, Cove (linear) and Downlight ...

  13. Non-Linear Seismic Soil Structure Interaction (SSI) Method for Developing Non-Linear Seismic SSI Analysis Techniques

    Broader source: Energy.gov [DOE]

    Non-Linear Seismic Soil Structure Interaction (SSI) Method for Developing Non-Linear Seismic SSI Analysis Techniques Justin Coleman, P.E. October 25th, 2011

  14. Enhanced dielectric-wall linear accelerator

    DOE Patents [OSTI]

    Sampayan, Stephen E.; Caporaso, George J.; Kirbie, Hugh C.

    1998-01-01

    A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface.

  15. Noise in phase-preserving linear amplifiers

    SciTech Connect (OSTI)

    Pandey, Shashank; Jiang, Zhang; Combes, Joshua; Caves, Carlton M.

    2014-12-04

    The purpose of a phase-preserving linear amplifier is to make a small signal larger, so that it can be perceived by instruments incapable of resolving the original signal, while sacrificing as little as possible in signal-to-noise. Quantum mechanics limits how well this can be done: the noise added by the amplifier, referred to the input, must be at least half a quantum at the operating frequency. This well-known quantum limit only constrains the second moments of the added noise. Here we provide the quantum constraints on the entire distribution of added noise: any phasepreserving linear amplifier is equivalent to a parametric amplifier with a physical state ? for the ancillary mode; ? determines the properties of the added noise.

  16. Enhanced dielectric-wall linear accelerator

    DOE Patents [OSTI]

    Sampayan, S.E.; Caporaso, G.J.; Kirbie, H.C.

    1998-09-22

    A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 6 figs.

  17. The Next Linear Collider: NLC2001

    SciTech Connect (OSTI)

    D. Burke et al.

    2002-01-14

    Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it is. These experiments must also define the next important threshold in energy. The need is to understand physics at the TeV energy scale as well as the physics at the 100-GeV energy scale is now understood. This will require both the LHC and a companion linear electron-positron collider. A first Zeroth-Order Design Report (ZDR) [2] for a second-generation electron-positron linear collider, the Next Linear Collider (NLC), was published five years ago. The NLC design is based on a high-frequency room-temperature rf accelerator. Its goal is exploration of elementary particle physics at the TeV center-of-mass energy, while learning how to design and build colliders at still higher energies. Many advances in accelerator technologies and improvements in the design of the NLC have been made since 1996. This Report is a brief update of the ZDR.

  18. Radio frequency quadrupole resonator for linear accelerator

    DOE Patents [OSTI]

    Moretti, Alfred

    1985-01-01

    An RFQ resonator for a linear accelerator having a reduced level of interfering modes and producing a quadrupole mode for focusing, bunching and accelerating beams of heavy charged particles, with the construction being characterized by four elongated resonating rods within a cylinder with the rods being alternately shorted and open electrically to the shell at common ends of the rods to provide an LC parallel resonant circuit when activated by a magnetic field transverse to the longitudinal axis.

  19. High gradient accelerators for linear light sources

    SciTech Connect (OSTI)

    Barletta, W.A.

    1988-09-26

    Ultra-high gradient radio frequency linacs powered by relativistic klystrons appear to be able to provide compact sources of radiation at XUV and soft x-ray wavelengths with a duration of 1 picosecond or less. This paper provides a tutorial review of the physics applicable to scaling the present experience of the accelerator community to the regime applicable to compact linear light sources. 22 refs., 11 figs., 21 tabs.

  20. Inpainting with sparse linear combinations of exemplars

    SciTech Connect (OSTI)

    Wohlberg, Brendt

    2008-01-01

    We introduce a new exemplar-based inpainting algorithm based on representing the region to be inpainted as a sparse linear combination of blocks extracted from similar parts of the image being inpainted. This method is conceptually simple, being computed by functional minimization, and avoids the complexity of correctly ordering the filling in of missing regions of other exemplar-based methods. Initial performance comparisons on small inpainting regions indicate that this method provides similar or better performance than other recent methods.

  1. Communications circuit including a linear quadratic estimator

    DOE Patents [OSTI]

    Ferguson, Dennis D.

    2015-07-07

    A circuit includes a linear quadratic estimator (LQE) configured to receive a plurality of measurements a signal. The LQE is configured to weight the measurements based on their respective uncertainties to produce weighted averages. The circuit further includes a controller coupled to the LQE and configured to selectively adjust at least one data link parameter associated with a communication channel in response to receiving the weighted averages.

  2. Towards a Future Linear Collider and The Linear Collider Studies at CERN

    ScienceCinema (OSTI)

    None

    2011-10-06

    During the week 18-22 October, more than 400 physicists will meet at CERN and in the CICG (International Conference Centre Geneva) to review the global progress towards a future linear collider. The 2010 International Workshop on Linear Colliders will study the physics, detectors and accelerator complex of a linear collider covering both the CLIC and ILC options. Among the topics presented and discussed will be the progress towards the CLIC Conceptual Design Report in 2011, the ILC Technical Design Report in 2012, physics and detector studies linked to these reports, and an increasing numbers of common working group activities. The seminar will give an overview of these topics and also CERN?s linear collider studies, focusing on current activities and initial plans for the period 2011-16. n.b: The Council Chamber is also reserved for this colloquium with a live transmission from the Main Auditorium.

  3. Microfabricated linear Paul-Straubel ion trap

    DOE Patents [OSTI]

    Mangan, Michael A. (Albuquerque, NM); Blain, Matthew G. (Albuquerque, NM); Tigges, Chris P. (Albuquerque, NM); Linker, Kevin L. (Albuquerque, NM)

    2011-04-19

    An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

  4. Micromechanism linear actuator with capillary force sealing

    DOE Patents [OSTI]

    Sniegowski, Jeffry J. (Albuquerque, NM)

    1997-01-01

    A class of micromachine linear actuators whose function is based on gas driven pistons in which capillary forces are used to seal the gas behind the piston. The capillary forces also increase the amount of force transmitted from the gas pressure to the piston. In a major subclass of such devices, the gas bubble is produced by thermal vaporization of a working fluid. Because of their dependence on capillary forces for sealing, such devices are only practical on the sub-mm size scale, but in that regime they produce very large force times distance (total work) values.

  5. Terahertz-driven linear electron acceleration

    SciTech Connect (OSTI)

    Nanni, Emilio A.; Huang, Wenqian R.; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Dwayne Miller, R. J.; Kärtner, Franz X.

    2015-10-06

    The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30–50 MeVm-1 gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. As a result, these ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams.

  6. Linear dimensions and volumes of human lungs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hickman, David P.

    2012-03-30

    TOTAL LUNG Capacity is defined as “the inspiratory capacity plus the functional residual capacity; the volume of air contained in the lungs at the end of a maximal inspiration; also equals vital capacity plus residual volume” (from MediLexicon.com). Within the Results and Discussion section of their April 2012 Health Physics paper, Kramer et al. briefly noted that the lungs of their experimental subjects were “not fully inflated.” By definition and failure to obtain maximal inspiration, Kramer et. al. did not measure Total Lung Capacity (TLC). The TLC equation generated from this work will tend to underestimate TLC and does notmore » improve or update total lung capacity data provided by ICRP and others. Likewise, the five linear measurements performed by Kramer et. al. are only representative of the conditions of the measurement (i.e., not at-rest volume, but not fully inflated either). While there was significant work performed and the data are interesting, the data does not represent a maximal situation, a minimal situation, or an at-rest situation. Moreover, while interesting, the linear data generated by this study is limited by the conditions of the experiment and may not be fully comparative with other lung or inspiratory parameters, measures, or physical dimensions.« less

  7. Terahertz-driven linear electron acceleration

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Nanni, Emilio A.; Huang, Wenqian R.; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Dwayne Miller, R. J.; Kärtner, Franz X.

    2015-10-06

    The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30–50 MeVm-1 gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton acceleratorsmore » with simple accelerating structures, high repetition rates and significant charge per bunch. As a result, these ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams.« less

  8. Linear nozzle with tailored gas plumes

    DOE Patents [OSTI]

    Kozarek, Robert L. (Apollo, PA); Straub, William D. (Pittsburgh, PA); Fischer, Joern E. (Bremen, DE); Leon, David D. (Murrysville, PA)

    2003-01-01

    There is claimed a method for depositing fluid material from a linear nozzle in a substantially uniform manner across and along a surface. The method includes directing gaseous medium through said nozzle to provide a gaseous stream at the nozzle exit that entrains fluid material supplied to the nozzle, said gaseous stream being provided with a velocity profile across the nozzle width that compensates for the gaseous medium's tendency to assume an axisymmetric configuration after leaving the nozzle and before reaching the surface. There is also claimed a nozzle divided into respective side-by-side zones, or preferably chambers, through which a gaseous stream can be delivered in various velocity profiles across the width of said nozzle to compensate for the tendency of this gaseous medium to assume an axisymmetric configuration.

  9. Radio frequency focused interdigital linear accelerator

    DOE Patents [OSTI]

    Swenson, Donald A.; Starling, W. Joel

    2006-08-29

    An interdigital (Wideroe) linear accelerator employing drift tubes, and associated support stems that couple to both the longitudinal and support stem electromagnetic fields of the linac, creating rf quadrupole fields along the axis of the linac to provide transverse focusing for the particle beam. Each drift tube comprises two separate electrodes operating at different electrical potentials as determined by cavity rf fields. Each electrode supports two fingers, pointing towards the opposite end of the drift tube, forming a four-finger geometry that produces an rf quadrupole field distribution along its axis. The fundamental periodicity of the structure is equal to one half of the particle wavelength .beta..lamda., where .beta. is the particle velocity in units of the velocity of light and .lamda. is the free space wavelength of the rf. Particles are accelerated in the gaps between drift tubes. The particle beam is focused in regions inside the drift tubes.

  10. Shortcuts to adiabaticity from linear response theory

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Acconcia, Thiago V.; Bonança, Marcus V. S.; Deffner, Sebastian

    2015-10-23

    A shortcut to adiabaticity is a finite-time process that produces the same final state as would result from infinitely slow driving. We show that such shortcuts can be found for weak perturbations from linear response theory. Moreover, with the help of phenomenological response functions, a simple expression for the excess work is found—quantifying the nonequilibrium excitations. For two specific examples, i.e., the quantum parametric oscillator and the spin 1/2 in a time-dependent magnetic field, we show that finite-time zeros of the excess work indicate the existence of shortcuts. We finally propose a degenerate family of protocols, which facilitates shortcuts tomore » adiabaticity for specific and very short driving times.« less

  11. Faraday rotation assisted by linearly polarized light

    SciTech Connect (OSTI)

    Choi, Jai Min; Kim, Jang Myun; Cho, D.

    2007-11-15

    We demonstrate a type of chiral effect of an atomic medium. Polarization rotation of a probe beam is observed only when both a magnetic field and a linearly polarized coupling beam are present. We compare it with other chiral effects like optical activity, the Faraday effect, and the optically induced Faraday effect from the viewpoint of spatial inversion and time reversal transformations. As a theoretical model we consider a five-level configuration involving the cesium D2 transition. We use spin-polarized cold cesium atoms trapped in a magneto-optical trap to measure the polarization rotation versus probe detuning. The result shows reasonable agreement with a calculation from the master equation of the five-level configuration.

  12. Shortcuts to adiabaticity from linear response theory

    SciTech Connect (OSTI)

    Acconcia, Thiago V.; Bonança, Marcus V. S.; Deffner, Sebastian

    2015-10-23

    A shortcut to adiabaticity is a finite-time process that produces the same final state as would result from infinitely slow driving. We show that such shortcuts can be found for weak perturbations from linear response theory. Moreover, with the help of phenomenological response functions, a simple expression for the excess work is found—quantifying the nonequilibrium excitations. For two specific examples, i.e., the quantum parametric oscillator and the spin 1/2 in a time-dependent magnetic field, we show that finite-time zeros of the excess work indicate the existence of shortcuts. We finally propose a degenerate family of protocols, which facilitates shortcuts to adiabaticity for specific and very short driving times.

  13. 2d PDE Linear Symmetric Matrix Solver

    Energy Science and Technology Software Center (OSTI)

    1983-10-01

    ICCG2 (Incomplete Cholesky factorized Conjugate Gradient algorithm for 2d symmetric problems) was developed to solve a linear symmetric matrix system arising from a 9-point discretization of two-dimensional elliptic and parabolic partial differential equations found in plasma physics applications, such as resistive MHD, spatial diffusive transport, and phase space transport (Fokker-Planck equation) problems. These problems share the common feature of being stiff and requiring implicit solution techniques. When these parabolic or elliptic PDE''s are discretized withmore » finite-difference or finite-element methods,the resulting matrix system is frequently of block-tridiagonal form. To use ICCG2, the discretization of the two-dimensional partial differential equation and its boundary conditions must result in a block-tridiagonal supermatrix composed of elementary tridiagonal matrices. The incomplete Cholesky conjugate gradient algorithm is used to solve the linear symmetric matrix equation. Loops are arranged to vectorize on the Cray1 with the CFT compiler, wherever possible. Recursive loops, which cannot be vectorized, are written for optimum scalar speed. For matrices lacking symmetry, ILUCG2 should be used. Similar methods in three dimensions are available in ICCG3 and ILUCG3. A general source containing extensions and macros, which must be processed by a pre-compiler to obtain the standard FORTRAN source, is provided along with the standard FORTRAN source because it is believed to be more readable. The pre-compiler is not included, but pre-compilation may be performed by a text editor as described in the UCRL-88746 Preprint.« less

  14. International linear collider reference design report

    SciTech Connect (OSTI)

    Aarons, G.

    2007-06-22

    The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of the project. This reference design provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D program, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.

  15. CALiPER Application Summary Report 19. LED Linear Pendants

    SciTech Connect (OSTI)

    none,

    2012-10-01

    Report 19 reviews the independently tested performance of nine LED linear pendants and also evaluates a collection of 11 linear pendant products available in both an LED and fluorescent version.

  16. Text-Alternative Version: LED Replacements for Linear Fluorescent Lamps

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "LED Replacements for Linear Fluorescent Lamps" webcast, held June 20, 2011.

  17. Governance of the International Linear Collider Project

    SciTech Connect (OSTI)

    Foster, B.; Barish, B.; Delahaye, J.P.; Dosselli, U.; Elsen, E.; Harrison, M.; Mnich, J.; Paterson, J.M.; Richard, F.; Stapnes, S.; Suzuki, A.; Wormser, G.; Yamada, S.; /KEK, Tsukuba

    2012-05-31

    Governance models for the International Linear Collider Project are examined in the light of experience from similar international projects around the world. Recommendations for one path which could be followed to realize the ILC successfully are outlined. The International Linear Collider (ILC) is a unique endeavour in particle physics; fully international from the outset, it has no 'host laboratory' to provide infrastructure and support. The realization of this project therefore presents unique challenges, in scientific, technical and political arenas. This document outlines the main questions that need to be answered if the ILC is to become a reality. It describes the methodology used to harness the wisdom displayed and lessons learned from current and previous large international projects. From this basis, it suggests both general principles and outlines a specific model to realize the ILC. It recognizes that there is no unique model for such a laboratory and that there are often several solutions to a particular problem. Nevertheless it proposes concrete solutions that the authors believe are currently the best choices in order to stimulate discussion and catalyze proposals as to how to bring the ILC project to fruition. The ILC Laboratory would be set up by international treaty and be governed by a strong Council to whom a Director General and an associated Directorate would report. Council would empower the Director General to give strong management to the project. It would take its decisions in a timely manner, giving appropriate weight to the financial contributions of the member states. The ILC Laboratory would be set up for a fixed term, capable of extension by agreement of all the partners. The construction of the machine would be based on a Work Breakdown Structure and value engineering and would have a common cash fund sufficiently large to allow the management flexibility to optimize the project's construction. Appropriate contingency, clearly apportioned at both a national and global level, is essential if the project is to be realised. Finally, models for running costs and decommissioning at the conclusion of the ILC project are proposed. This document represents an interim report of the bodies and individuals studying these questions inside the structure set up and supervised by the International Committee for Future Accelerators (ICFA). It represents a request for comment to the international community in all relevant disciplines, scientific, technical and most importantly, political. Many areas require further study and some, in particular the site selection process, have not yet progressed sufficiently to be addressed in detail in this document. Discussion raised by this document will be vital in framing the final proposals due to be published in 2012 in the Technical Design Report being prepared by the Global Design Effort of the ILC.

  18. LED Linear Lamps and Troffer Lighting | Department of Energy

    Energy Savers [EERE]

    Linear Lamps and Troffer Lighting LED Linear Lamps and Troffer Lighting View the video about CALiPER Series 21 on LED Linear Lamps and Troffer Lighting. The CALiPER program performed a series of investigations on linear LED lamps. Each report in the series covers the performance of up to 31 linear LED lamps, which were purchased in late 2012 or 2013. The first report focuses on bare lamp performance of LED T8 replacement lamps and subsequent reports examine performance in various troffers, as

  19. Liquid cooled, linear focus solar cell receiver

    DOE Patents [OSTI]

    Kirpich, Aaron S. (Broomall, PA)

    1985-01-01

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  20. Liquid cooled, linear focus solar cell receiver

    DOE Patents [OSTI]

    Kirpich, A.S.

    1983-12-08

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  1. Precision envelope detector and linear rectifier circuitry

    DOE Patents [OSTI]

    Davis, Thomas J. (Richland, WA)

    1980-01-01

    Disclosed is a method and apparatus for the precise linear rectification and envelope detection of oscillatory signals. The signal is applied to a voltage-to-current converter which supplies current to a constant current sink. The connection between the converter and the sink is also applied through a diode and an output load resistor to a ground connection. The connection is also connected to ground through a second diode of opposite polarity from the diode in series with the load resistor. Very small amplitude voltage signals applied to the converter will cause a small change in the output current of the converter, and the difference between the output current and the constant current sink will be applied either directly to ground through the single diode, or across the output load resistor, dependent upon the polarity. Disclosed also is a full-wave rectifier utilizing constant current sinks and voltage-to-current converters. Additionally, disclosed is a combination of the voltage-to-current converters with differential integrated circuit preamplifiers to boost the initial signal amplitude, and with low pass filtering applied so as to obtain a video or signal envelope output.

  2. VINETA II: A linear magnetic reconnection experiment

    SciTech Connect (OSTI)

    Bohlin, H. Von Stechow, A.; Rahbarnia, K.; Grulke, O.; Klinger, T.; Ernst-Moritz-Arndt University, Domstr. 11, 17489 Greifswald

    2014-02-15

    A linear experiment dedicated to the study of driven magnetic reconnection is presented. The new device (VINETA II) is suitable for investigating both collisional and near collisionless reconnection. Reconnection is achieved by externally driving magnetic field lines towards an X-point, inducing a current in the background plasma which consequently modifies the magnetic field topology. Owing to the open field line configuration of the experiment, the current is limited by the axial sheath boundary conditions. A plasma gun is used as an additional electron source in order to counterbalance the charge separation effects and supply the required current. Two drive methods are used in the device. First, an oscillating current through two parallel conductors drive the reconnection. Second, a stationary X-point topology is formed by the parallel conductors, and the drive is achieved by an oscillating current through a third conductor. In the first setup, the magnetic field of the axial plasma current dominates the field topology near the X-point throughout most of the drive. The second setup allows for the amplitude of the plasma current as well as the motion of the flux to be set independently of the X-point topology of the parallel conductors.

  3. Linear air-fuel sensor development

    SciTech Connect (OSTI)

    Garzon, F.; Miller, C.

    1996-12-14

    The electrochemical zirconia solid electrolyte oxygen sensor, is extensively used for monitoring oxygen concentrations in various fields. They are currently utilized in automobiles to monitor the exhaust gas composition and control the air-to-fuel ratio, thus reducing harmful emission components and improving fuel economy. Zirconia oxygen sensors, are divided into two classes of devices: (1) potentiometric or logarithmic air/fuel sensors; and (2) amperometric or linear air/fuel sensors. The potentiometric sensors are ideally suited to monitor the air-to-fuel ratio close to the complete combustion stoichiometry; a value of about 14.8 to 1 parts by volume. This occurs because the oxygen concentration changes by many orders of magnitude as the air/fuel ratio is varied through the stoichiometric value. However, the potentiometric sensor is not very sensitive to changes in oxygen partial pressure away from the stoichiometric point due to the logarithmic dependence of the output voltage signal on the oxygen partial pressure. It is often advantageous to operate gasoline power piston engines with excess combustion air; this improves fuel economy and reduces hydrocarbon emissions. To maintain stable combustion away from stoichiometry, and enable engines to operate in the excess oxygen (lean burn) region several limiting-current amperometric sensors have been reported. These sensors are based on the electrochemical oxygen ion pumping of a zirconia electrolyte. They typically show reproducible limiting current plateaus with an applied voltage caused by the gas diffusion overpotential at the cathode.

  4. Linear Fixed-Field Multi-Pass Arcs for Recirculating Linear Accelerators

    SciTech Connect (OSTI)

    V.S. Morozov, S.A. Bogacz, Y.R. Roblin, K.B. Beard

    2012-06-01

    Recirculating Linear Accelerators (RLA's) provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac for multiple passes. In the conventional scheme, after each pass, the different energy beams coming out of the linac are separated and directed into appropriate arcs for recirculation, with each pass requiring a separate fixed-energy arc. In this paper we present a concept of an RLA return arc based on linear combined-function magnets, in which two and potentially more consecutive passes with very different energies are transported through the same string of magnets. By adjusting the dipole and quadrupole components of the constituting linear combined-function magnets, the arc is designed to be achromatic and to have zero initial and final reference orbit offsets for all transported beam energies. We demonstrate the concept by developing a design for a droplet-shaped return arc for a dog-bone RLA capable of transporting two beam passes with momenta different by a factor of two. We present the results of tracking simulations of the two passes and lay out the path to end-to-end design and simulation of a complete dog-bone RLA.

  5. High-gradient compact linear accelerator

    DOE Patents [OSTI]

    Carder, B.M.

    1998-05-26

    A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the dielectric core. All the field segments in the dielectric core are then in unipolar agreement until the slower wave finally propagates to the third dielectric core across the dielectric plates with the wider spacing and higher dielectric constant. During such unipolar agreement, particles in the core are accelerated with gradients that exceed twenty megavolts per meter. 10 figs.

  6. 2d PDE Linear Asymmetric Matrix Solver

    Energy Science and Technology Software Center (OSTI)

    1983-10-01

    ILUCG2 (Incomplete LU factorized Conjugate Gradient algorithm for 2d problems) was developed to solve a linear asymmetric matrix system arising from a 9-point discretization of two-dimensional elliptic and parabolic partial differential equations found in plasma physics applications, such as plasma diffusion, equilibria, and phase space transport (Fokker-Planck equation) problems. These equations share the common feature of being stiff and requiring implicit solution techniques. When these parabolic or elliptic PDE''s are discretized with finite-difference or finite-elementmore » methods, the resulting matrix system is frequently of block-tridiagonal form. To use ILUCG2, the discretization of the two-dimensional partial differential equation and its boundary conditions must result in a block-tridiagonal supermatrix composed of elementary tridiagonal matrices. A generalization of the incomplete Cholesky conjugate gradient algorithm is used to solve the matrix equation. Loops are arranged to vectorize on the Cray1 with the CFT compiler, wherever possible. Recursive loops, which cannot be vectorized, are written for optimum scalar speed. For problems having a symmetric matrix ICCG2 should be used since it runs up to four times faster and uses approximately 30% less storage. Similar methods in three dimensions are available in ICCG3 and ILUCG3. A general source, containing extensions and macros, which must be processed by a pre-compiler to obtain the standard FORTRAN source, is provided along with the standard FORTRAN source because it is believed to be more readable. The pre-compiler is not included, but pre-compilation may be performed by a text editor as described in the UCRL-88746 Preprint.« less

  7. Electronic Non-Contacting Linear Position Measuring System

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2005-06-14

    A non-contacting linear position location system employs a special transmission line to encode and transmit magnetic signals to a receiver on the object whose position is to be measured. The invention is useful as a non-contact linear locator of moving objects, e.g., to determine the location of a magnetic-levitation train for the operation of the linear-synchronous motor drive system.

  8. International Linear Collider-A Technical Progress Report (Technical

    Office of Scientific and Technical Information (OSTI)

    Report) | SciTech Connect Technical Report: International Linear Collider-A Technical Progress Report Citation Details In-Document Search Title: International Linear Collider-A Technical Progress Report The International Linear Collider: A Technical Progress Report marks the halfway point towards the Global Design Effort fulfilling its mandate to follow up the ILC Reference Design Report with a more optimised Technical Design Report (TDR) by the end of 2012. The TDR will be based on much of

  9. Achieving large linear elasticity and high strength in bulk nanocompsite

    Office of Scientific and Technical Information (OSTI)

    via synergistic effect (Journal Article) | DOE PAGES DOE PAGES Search Results Accepted Manuscript: Achieving large linear elasticity and high strength in bulk nanocompsite via synergistic effect Title: Achieving large linear elasticity and high strength in bulk nanocompsite via synergistic effect Elastic strain in bulk metallic materials is usually limited to only a fraction of 1%. Developing bulk metallic materials showing large linear elasticity and high strength has proven to be

  10. A Fast Monte Carlo Simulation for the International Linear Collider

    Office of Scientific and Technical Information (OSTI)

    Detector (Technical Report) | SciTech Connect A Fast Monte Carlo Simulation for the International Linear Collider Detector Citation Details In-Document Search Title: A Fast Monte Carlo Simulation for the International Linear Collider Detector The following paper contains details concerning the motivation for, implementation and performance of a Java-based fast Monte Carlo simulation for a detector designed to be used in the International Linear Collider. This simulation, presently included

  11. The Linear Engine Pathway of Transformation | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The Linear Engine Pathway of Transformation The Linear Engine Pathway of Transformation This poster highlights the major milestones in the history of the linear engine in terms of technological advances, novel designs, and economic/social impact. PDF icon p-06_covington.pdf More Documents & Publications Difficulty of Measuring Emissions from Heavy-Duty Engines Equipped with SCR and DPF Development of a Stand-Alone Urea-SCR System for NOx Reduction in Marine Diesel Engines Modeling the

  12. LED Replacements for Linear Fluorescent Lamps Webcast | Department of

    Energy Savers [EERE]

    Energy Replacements for Linear Fluorescent Lamps Webcast LED Replacements for Linear Fluorescent Lamps Webcast In this June 20, 2011 webcast on LED products marketed as replacements for linear fluorescent lamps, Jason Tuenge of the Pacific Northwest National Laboratory (PNNL) discussed current Lighting Facts-listed products as well as products evaluated in the latest CALiPER reports. Eric Richman, also of PNNL, reported on a recently completed GATEWAY demonstration project, in which LED and

  13. High Impact Technology HQ - Results - LED Troffer, Cove (linear) and

    Energy Savers [EERE]

    Downlight Retrofit Kits: Princeton Icahn Laboratory | Department of Energy HQ - Results - LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory High Impact Technology HQ - Results - LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory PDF icon LED Troffer, Cove (linear) and Downlight Retrofit Kits: Princeton Icahn Laboratory More Documents & Publications DOE Booth Presentations From Grainger Show 2015 Downloads Exterior LED

  14. DOE - Office of Legacy Management -- Stanford Linear Accelerator Center -

    Office of Legacy Management (LM)

    005 Stanford Linear Accelerator Center - 005 FUSRAP Considered Sites Site: Stanford Linear Accelerator Center (005) Designated Name: Alternate Name: Location: Evaluation Year: Site Operations: Site Disposition: Radioactive Materials Handled: Primary Radioactive Materials Handled: Radiological Survey(s): Site Status: The Stanford Linear Accelerator Center was established in 1962 as a research facility for high energy particle physics. The Environmental Management mission at this site is to

  15. Linear electric field time-of-flight ion mass spectrometer

    DOE Patents [OSTI]

    Funsten, Herbert O. (Los Alamos, NM); Feldman, William C. (Los Alamos, NM)

    2008-06-10

    A linear electric field ion mass spectrometer having an evacuated enclosure with means for generating a linear electric field located in the evacuated enclosure and means for injecting a sample material into the linear electric field. A source of pulsed ionizing radiation injects ionizing radiation into the linear electric field to ionize atoms or molecules of the sample material, and timing means determine the time elapsed between ionization of atoms or molecules and arrival of an ion out of the ionized atoms or molecules at a predetermined position.

  16. The Klynac: An Integrated Klystron and Linear Accelerator

    SciTech Connect (OSTI)

    Potter, J. M., Schwellenbach, D., Meidinger, A.

    2012-08-07

    The Klynac concept integrates an electron gun, a radio frequency (RF) power source, and a coupled-cavity linear accelerator into a single resonant system

  17. Linear Concentrator System Basics for Concentrating Solar Power...

    Office of Environmental Management (EM)

    Linear concentrating solar power (CSP) collectors capture the sun's energy with large mirrors that reflect and ... In the future, troughs may be integrated with existing or new ...

  18. Simultaneous linear optics and coupling correction for storage...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data Citation Details In-Document Search Title:...

  19. Discrimination of new physics models with the International Linear...

    Office of Scientific and Technical Information (OSTI)

    Discrimination of new physics models with the International Linear Collider Citation Details In-Document Search Title: Discrimination of new physics models with the International ...

  20. Knot Undulator to Generate Linearly Polarized Photons with Low...

    Office of Scientific and Technical Information (OSTI)

    Technical Information Service, Springfield, VA at www.ntis.gov. Heat load on beamline optics is a serious problem to generate pure linearly polarized photons in the third...

  1. Linearly Polarized Thermal Emitter for More Efficient Thermophotovolta...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Thermal Solar Thermal Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Linearly Polarized Thermal Emitter for More Efficient Thermophotovoltaic Devices...

  2. Neutrino mass, dark energy, and the linear growth factor (Journal...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Neutrino mass, dark energy, and the linear ... OSTI Identifier: 21249781 Resource Type: Journal Article Resource Relation: Journal Name: ...

  3. Optimizing minimum free-energy crossing points in solution: Linear...

    Office of Scientific and Technical Information (OSTI)

    Optimizing minimum free-energy crossing points in solution: Linear-response free energyspin-flip density functional theory approach Citation Details In-Document Search Title:...

  4. Physics Case for the International Linear Collider (Technical...

    Office of Scientific and Technical Information (OSTI)

    Collider We summarize the physics case for the International Linear Collider (ILC). We review the key motivations for the ILC presented in the literature, updating the projected...

  5. Resource-Efficient Generataion of Linear Cluster States by Linear Optics with postselection

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Uskov, Dmitry B; Alsing, Paul; Fanto, Michael; Kaplan, Lev; Kim, R; Szep, Atilla; Smith IV, Amos M

    2015-01-01

    We report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detectionmore » of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2^n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4^m-1.« less

  6. Resource-Efficient Generataion of Linear Cluster States by Linear Optics with postselection

    SciTech Connect (OSTI)

    Uskov, Dmitry B; Alsing, Paul; Fanto, Michael; Kaplan, Lev; Kim, R; Szep, Atilla; Smith IV, Amos M

    2015-01-01

    We report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detection of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2^n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4^m-1.

  7. Drift tube suspension for high intensity linear accelerators

    DOE Patents [OSTI]

    Liska, D.J.; Schamaun, R.G.; Clark, D.C.; Potter, R.C.; Frank, J.A.

    1980-03-11

    The disclosure relates to a drift tube suspension for high intensity linear accelerators. The system comprises a series of box-sections girders independently adjustably mounted on a linear accelerator. A plurality of drift tube holding stems are individually adjustably mounted on each girder.

  8. Drift tube suspension for high intensity linear accelerators

    DOE Patents [OSTI]

    Liska, Donald J. (Los Alamos, NM); Schamaun, Roger G. (Los Alamos, NM); Clark, Donald C. (Los Alamos, NM); Potter, R. Christopher (Los Alamos, NM); Frank, Joseph A. (Los Alamos, NM)

    1982-01-01

    The disclosure relates to a drift tube suspension for high intensity linear accelerators. The system comprises a series of box-sections girders independently adjustably mounted on a linear accelerator. A plurality of drift tube holding stems are individually adjustably mounted on each girder.

  9. Variable-energy drift-tube linear accelerator

    DOE Patents [OSTI]

    Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM); Potter, James M. (Los Alamos, NM); Stovall, James E. (Los Alamos, NM)

    1984-01-01

    A linear accelerator system includes a plurality of post-coupled drift-tubes wherein each post coupler is bistably positionable to either of two positions which result in different field distributions. With binary control over a plurality of post couplers, a significant accumlative effect in the resulting field distribution is achieved yielding a variable-energy drift-tube linear accelerator.

  10. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOE Patents [OSTI]

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  11. Comparison of open-source linear programming solvers.

    SciTech Connect (OSTI)

    Gearhart, Jared Lee; Adair, Kristin Lynn; Durfee, Justin D.; Jones, Katherine A.; Martin, Nathaniel; Detry, Richard Joseph

    2013-10-01

    When developing linear programming models, issues such as budget limitations, customer requirements, or licensing may preclude the use of commercial linear programming solvers. In such cases, one option is to use an open-source linear programming solver. A survey of linear programming tools was conducted to identify potential open-source solvers. From this survey, four open-source solvers were tested using a collection of linear programming test problems and the results were compared to IBM ILOG CPLEX Optimizer (CPLEX) [1], an industry standard. The solvers considered were: COIN-OR Linear Programming (CLP) [2], [3], GNU Linear Programming Kit (GLPK) [4], lp_solve [5] and Modular In-core Nonlinear Optimization System (MINOS) [6]. As no open-source solver outperforms CPLEX, this study demonstrates the power of commercial linear programming software. CLP was found to be the top performing open-source solver considered in terms of capability and speed. GLPK also performed well but cannot match the speed of CLP or CPLEX. lp_solve and MINOS were considerably slower and encountered issues when solving several test problems.

  12. Nonlinear vs. linear biasing in Trp-cage folding simulations

    SciTech Connect (OSTI)

    Spiwok, Vojt?ch Oborsk, Pavel; Krlov, Blanka; Pazrikov, Jana

    2015-03-21

    Biased simulations have great potential for the study of slow processes, including protein folding. Atomic motions in molecules are nonlinear, which suggests that simulations with enhanced sampling of collective motions traced by nonlinear dimensionality reduction methods may perform better than linear ones. In this study, we compare an unbiased folding simulation of the Trp-cage miniprotein with metadynamics simulations using both linear (principle component analysis) and nonlinear (Isomap) low dimensional embeddings as collective variables. Folding of the mini-protein was successfully simulated in 200?ns simulation with linear biasing and non-linear motion biasing. The folded state was correctly predicted as the free energy minimum in both simulations. We found that the advantage of linear motion biasing is that it can sample a larger conformational space, whereas the advantage of nonlinear motion biasing lies in slightly better resolution of the resulting free energy surface. In terms of sampling efficiency, both methods are comparable.

  13. Non-linear Seismic Soil Structure Interaction Method for Developing Nonlinear Seismic SSI

    Office of Environmental Management (EM)

    Non-Linear Seismic Soil Structure Interaction (SSI) Method for Developing Non-Linear Seismic SSI Analysis Techniques Justin Coleman, P.E. October 25th, 2011 E102003020BDS Presentation Outline  Purpose of Presentation  Linear versus Non-Linear Seismic SSI  Non-Linear seismic Soil Structure Interaction (NLSSI) Studies  The NLSSI Introduction  Non-Linearity in Seismic SSI Analysis  Commercial Software Elements  Commercial Software Non-Linear Constitutive Models  Non-Linear

  14. Non-linear stochastic growth rates and redshift space distortions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jennings, Elise; Jennings, David

    2015-04-09

    The linear growth rate is commonly defined through a simple deterministic relation between the velocity divergence and the matter overdensity in the linear regime. We introduce a formalism that extends this to a non-linear, stochastic relation between θ = ∇ ∙ v(x,t)/aH and δ. This provides a new phenomenological approach that examines the conditional mean <θ|δ>, together with the fluctuations of θ around this mean. We also measure these stochastic components using N-body simulations and find they are non-negative and increase with decreasing scale from ~10 per cent at k < 0.2 h Mpc-1 to 25 per cent at kmore » ~ 0.45 h Mpc-1 at z = 0. Both the stochastic relation and non-linearity are more pronounced for haloes, M ≤ 5 × 1012 M⊙ h-1, compared to the dark matter at z = 0 and 1. Non-linear growth effects manifest themselves as a rotation of the mean <θ|δ> away from the linear theory prediction -fLTδ, where fLT is the linear growth rate. This rotation increases with wavenumber, k, and we show that it can be well-described by second-order Lagrangian perturbation theory (2LPT) fork < 0.1 h Mpc-1. Furthermore, the stochasticity in the θ – δ relation is not so simply described by 2LPT, and we discuss its impact on measurements of fLT from two-point statistics in redshift space. Furthermore, given that the relationship between δ and θ is stochastic and non-linear, this will have implications for the interpretation and precision of fLT extracted using models which assume a linear, deterministic expression.« less

  15. Asynchronous parallel generating set search for linearly-constrained optimization.

    SciTech Connect (OSTI)

    Lewis, Robert Michael; Griffin, Joshua D.; Kolda, Tamara Gibson

    2006-08-01

    Generating set search (GSS) is a family of direct search methods that encompasses generalized pattern search and related methods. We describe an algorithm for asynchronous linearly-constrained GSS, which has some complexities that make it different from both the asynchronous bound-constrained case as well as the synchronous linearly-constrained case. The algorithm has been implemented in the APPSPACK software framework and we present results from an extensive numerical study using CUTEr test problems. We discuss the results, both positive and negative, and conclude that GSS is a reliable method for solving small-to-medium sized linearly-constrained optimization problems without derivatives.

  16. Fourth order resonance of a high intensity linear accelerator* (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Fourth order resonance of a high intensity linear accelerator* Citation Details In-Document Search Title: Fourth order resonance of a high intensity linear accelerator* For a high intensity beam, the 4\nu=1 resonance of a linear accelerator is manifested through the octupolar term of space charge potential when the depressed phase advance \sigma is close to and below 90 but no resonance effect is observed when \sigma just above 90 . To verify that this is a

  17. Thermodynamics of a lattice gas with linear attractive potential (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Thermodynamics of a lattice gas with linear attractive potential Citation Details In-Document Search Title: Thermodynamics of a lattice gas with linear attractive potential We study the equilibrium thermodynamics of a one-dimensional lattice gas with interaction V(|i-j|)=-1/(μn) (ξ-1/n |i-j|) given by the superposition of a universal attractive interaction with strength -1/(μn) ξ<0, and a linear attractive potential 1/(μn{sup 2}) |i-j|. The interaction is

  18. Top Quark Anomalous Couplings at the International Linear Collider (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Quark Anomalous Couplings at the International Linear Collider Citation Details In-Document Search Title: Top Quark Anomalous Couplings at the International Linear Collider We present a study of the experimental determination of the forward-backward asymmetry in the process e{sup +}e{sup -} {yields} t{bar t} and in the subsequent t {yields} Wb decay, studied in the context of the International Linear Collider. This process probes the elementary couplings of the top

  19. Spin relaxation and linear-in-electric-field frequency shift...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Spin relaxation and linear-in-electric-field frequency shift in an ... It is found that the rectangular cell geometry admits of a general result for Tsub 1, ...

  20. Linear Scaling Electronic Structure Methods with Periodic Boundary Conditions

    SciTech Connect (OSTI)

    Gustavo E. Scuseria

    2008-02-08

    The methodological development and computational implementation of linear scaling quantum chemistry methods for the accurate calculation of electronic structure and properties of periodic systems (solids, surfaces, and polymers) and their application to chemical problems of DOE relevance.

  1. Linear Scaling of the Exciton Binding Energy versus the Band...

    Office of Scientific and Technical Information (OSTI)

    Linear Scaling of the Exciton Binding Energy versus the Band Gap of Two-Dimensional Materials This content will become publicly available on August 6, 2016 Prev Next Title:...

  2. A Linear Theory of Microwave Instability in Electron Storage...

    Office of Scientific and Technical Information (OSTI)

    Title: A Linear Theory of Microwave Instability in Electron Storage Rings The well-known ... in an analysis of this stability that are associated with the potential-well distortion. ...

  3. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Using spectroscopic information for magnetometry and magnetic microscopy obviously requires detailed theoretical understanding of spectral shape and magnitude of dichroism signals. A research team at ALS Beamline 4.0.2 has now shown unambiguously that, contrary to common belief, spectral shape and magnitude of x-ray magnetic linear dichroism (XMLD) are not only determined by the relative orientation of magnetic moments and

  4. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, C.M.

    1998-12-15

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine is described. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod. 8 figs.

  5. Ordinary Isotropic Peridynamic Models; Position Aware Linear Solid (PALS).

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Ordinary Isotropic Peridynamic Models; Position Aware Linear Solid (PALS). Citation Details In-Document Search Title: Ordinary Isotropic Peridynamic Models; Position Aware Linear Solid (PALS). Abstract not provided. Authors: Mitchell, John Anthony Publication Date: 2015-02-01 OSTI Identifier: 1239086 Report Number(s): SAND2015-1012PE 566979 DOE Contract Number: AC04-94AL85000 Resource Type: Conference Resource Relation: Conference: Proposed for presentation at

  6. International Linear Collider Technical Design Report - Volume 2: Physics

    Office of Scientific and Technical Information (OSTI)

    (Technical Report) | SciTech Connect International Linear Collider Technical Design Report - Volume 2: Physics Citation Details In-Document Search Title: International Linear Collider Technical Design Report - Volume 2: Physics Authors: Baer, Howard ; Barklow, Tim ; Fujii, Keisuke ; Gao, Yuanning ; Hoang, Andre ; Kanemura, Shinya ; List, Jenny ; Logan, Heather E. ; Nomerotski, Andrei ; Perelstein, Maxim ; Peskin, Michael E. ; Poschl, Roman ; Reuter, Jurgen ; Riemann, Sabine ; Savoy-Navarro,

  7. Linear theory of microwave instability in electron storage rings (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Linear theory of microwave instability in electron storage rings Citation Details In-Document Search Title: Linear theory of microwave instability in electron storage rings Authors: Cai, Yunhai Publication Date: 2011-06-14 OSTI Identifier: 1099585 Type: Published Article Journal Name: Physical Review Special Topics - Accelerators and Beams Additional Journal Information: Journal Volume: 14; Journal Issue: 6; Journal ID: ISSN 1098-4402 Publisher: American Physical

  8. Ubiquity of linear resistivity at intermediate temperature in bad metals

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | DOE PAGES Ubiquity of linear resistivity at intermediate temperature in bad metals Title: Ubiquity of linear resistivity at intermediate temperature in bad metals Authors: Boyd, G. R. ; Zlatić, V. ; Freericks, J. K. Publication Date: 2015-02-20 OSTI Identifier: 1181226 Grant/Contract Number: SC0007091; FG02-08ER46542 Type: Publisher's Accepted Manuscript Journal Name: Physical Review B Additional Journal Information: Journal Volume: 91; Journal Issue: 7; Journal ID: ISSN

  9. Discrimination of new physics models with the International Linear Collider

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Discrimination of new physics models with the International Linear Collider Citation Details In-Document Search Title: Discrimination of new physics models with the International Linear Collider Authors: Asano, Masaki ; Saito, Tomoyuki ; Suehara, Taikan ; Fujii, Keisuke ; Hundi, R. S. ; Itoh, Hideo ; Matsumoto, Shigeki ; Okada, Nobuchika ; Takubo, Yosuke ; Yamamoto, Hitoshi Publication Date: 2011-12-02 OSTI Identifier: 1098342 Type: Publisher's Accepted

  10. A posteriori error analysis of parameterized linear systems using spectral

    Office of Scientific and Technical Information (OSTI)

    methods. (Journal Article) | SciTech Connect Journal Article: A posteriori error analysis of parameterized linear systems using spectral methods. Citation Details In-Document Search Title: A posteriori error analysis of parameterized linear systems using spectral methods. Abstract not provided. Authors: Constantine, Paul ; Butler, Troy Publication Date: 2011-07-01 OSTI Identifier: 1106467 Report Number(s): SAND2011-4711J 463817 DOE Contract Number: AC04-94AL85000 Resource Type: Journal

  11. Direct Probes of Linearly Polarized Gluons inside Unpolarized Hadrons

    SciTech Connect (OSTI)

    Boer, Daniel; /Groningen, KVI; Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; Mulders, Piet J.; /Brussels U., IIHE; Pisano, Cristian; /Cagliari U. /INFN, Cagliari

    2011-02-07

    We show that the unmeasured distribution of linearly polarized gluons inside unpolarized hadrons can be directly probed in jet or heavy quark pair production both in electron-hadron and hadron-hadron collisions. We present expressions for the simplest cos 2{phi} asymmetries and estimate their maximal value in the particular case of electron-hadron collisions. Measurements of the linearly polarized gluon distribution in the proton should be feasible in future EIC or LHeC experiments.

  12. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Using spectroscopic information for magnetometry and magnetic microscopy obviously requires detailed theoretical understanding of spectral shape and magnitude of dichroism signals. A research team at ALS Beamline 4.0.2 has now shown unambiguously that, contrary to common belief, spectral shape and magnitude of x-ray magnetic linear dichroism (XMLD) are not only determined by the relative orientation of magnetic moments and

  13. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Using spectroscopic information for magnetometry and magnetic microscopy obviously requires detailed theoretical understanding of spectral shape and magnitude of dichroism signals. A research team at ALS Beamline 4.0.2 has now shown unambiguously that, contrary to common belief, spectral shape and magnitude of x-ray magnetic linear dichroism (XMLD) are not only determined by the relative orientation of magnetic moments and

  14. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Using spectroscopic information for magnetometry and magnetic microscopy obviously requires detailed theoretical understanding of spectral shape and magnitude of dichroism signals. A research team at ALS Beamline 4.0.2 has now shown unambiguously that, contrary to common belief, spectral shape and magnitude of x-ray magnetic linear dichroism (XMLD) are not only determined by the relative orientation of magnetic moments and

  15. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Using spectroscopic information for magnetometry and magnetic microscopy obviously requires detailed theoretical understanding of spectral shape and magnitude of dichroism signals. A research team at ALS Beamline 4.0.2 has now shown unambiguously that, contrary to common belief, spectral shape and magnitude of x-ray magnetic linear dichroism (XMLD) are not only determined by the relative orientation of magnetic moments and

  16. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism Print Wednesday, 29 August 2007 00:00 Using spectroscopic information for magnetometry and magnetic microscopy obviously requires detailed theoretical understanding of spectral shape and magnitude of dichroism signals. A research team at ALS Beamline 4.0.2 has now shown unambiguously that, contrary to common belief, spectral shape and magnitude of x-ray magnetic

  17. International Linear Collider Technical Design Report - Volume 2: Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (Technical Report) | SciTech Connect International Linear Collider Technical Design Report - Volume 2: Physics Citation Details In-Document Search Title: International Linear Collider Technical Design Report - Volume 2: Physics Authors: Baer, Howard ; Barklow, Tim ; Fujii, Keisuke ; Gao, Yuanning ; Hoang, Andre ; Kanemura, Shinya ; List, Jenny ; Logan, Heather E. ; Nomerotski, Andrei ; Perelstein, Maxim ; Peskin, Michael E. ; Poschl, Roman ; Reuter, Jurgen ; Riemann, Sabine ; Savoy-Navarro,

  18. JLab Supports International Linear Collider Cavity Development Work |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jefferson Lab Supports International Linear Collider Cavity Development Work NEWPORT NEWS, Va. Feb. 12, 2008 - It's not often that major-league baseball and nuclear physics get to share the limelight, but that's what's happening at the Department of Energy's Jefferson Lab. The baseball connection involves a nine-cell niobium cavity developed by KEK accelerator scientists in Japan as one of several designs being tested for development for the proposed International Linear Collider. JLab is

  19. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, Carsten M. (Dadeville, AL)

    1998-01-01

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod.

  20. Top Quark Anomalous Couplings at the International Linear Collider (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Top Quark Anomalous Couplings at the International Linear Collider Citation Details In-Document Search Title: Top Quark Anomalous Couplings at the International Linear Collider × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science and

  1. Top quark anomalous couplings at the International Linear Collider (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Top quark anomalous couplings at the International Linear Collider Citation Details In-Document Search Title: Top quark anomalous couplings at the International Linear Collider Authors: Devetak, Erik ; Nomerotski, Andrei ; Peskin, Michael Publication Date: 2011-08-17 OSTI Identifier: 1100572 Type: Publisher's Accepted Manuscript Journal Name: Physical Review D Additional Journal Information: Journal Volume: 84; Journal Issue: 3; Journal ID: ISSN 1550-7998

  2. Toward portable programming of numerical linear algebra on manycore nodes.

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Toward portable programming of numerical linear algebra on manycore nodes. Citation Details In-Document Search Title: Toward portable programming of numerical linear algebra on manycore nodes. Abstract not provided. Authors: Heroux, Michael Allen Publication Date: 2011-05-01 OSTI Identifier: 1109301 Report Number(s): SAND2011-3556C 471555 DOE Contract Number: AC04-94AL85000 Resource Type: Conference Resource Relation: Conference: Toward petaflop numerical

  3. Linear Concentrator System Basics for Concentrating Solar Power |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Linear Concentrator System Basics for Concentrating Solar Power Linear Concentrator System Basics for Concentrating Solar Power August 20, 2013 - 4:45pm Addthis Photo of numerous parallel rows of parabolic trough collectors tracking the sun. Cooling towers and other generator equipment are in the midst of the troughs, and two water tanks are in the background. The Solar Electric Generating Station IV power plant in California consists of many parallel rows of parabolic

  4. 2010 Annual Planning Summary for Stanford Linear Accelerator Center Site

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Office (SLAC) | Department of Energy Stanford Linear Accelerator Center Site Office (SLAC) 2010 Annual Planning Summary for Stanford Linear Accelerator Center Site Office (SLAC) Annual Planning Summaries briefly describe the status of ongoing NEPA compliance activities, any EAs expected to be prepared in the next 12 months, any EISs expected to be prepared in the next 24 months, and the planned cost and schedule for each NEPA review identified. PDF icon 2010 Annual Planning Summary for

  5. Higher-degree linear approximations of nonlinear systems

    SciTech Connect (OSTI)

    Karahan, S.

    1989-01-01

    In this dissertation, the author develops a new method for obtaining higher degree linear approximations of nonlinear control systems. The standard approach in the analysis and synthesis of nonlinear systems is a first order approximation by a linear model. This is usually performed by obtaining a series expansion of the system at some nominal operating point and retaining only the first degree terms in the series. The accuracy of this approximation depends on how far the system moves away from the normal point, and on the relative magnitudes of the higher degree terms in the series expansion. The approximation is achieved by finding an appropriate nonlinear coordinate transformation-feedback pair to perform the higher degree linearization. With the proposed method, one can improve the accuracy of the approximation up to arbitrarily higher degrees, provided certain solvability conditions are satisfied. The Hunt-Su linearizability theorem makes these conditions precise. This approach is similar to Poincare's Normal Form Theorem in formulation, but different in its solution method. After some mathematical background the author derives a set of equations (called the Homological Equations). A solution to this system of linear equations is equivalent to the solution to the problem of approximate linearization. However, it is generally not possible to solve the system of equations exactly. He outlines a method for systematically finding approximate solutions to these equations using singular value decomposition, while minimizing an error with respect to some defined norm.

  6. Modeling patterns in data using linear and related models

    SciTech Connect (OSTI)

    Engelhardt, M.E.

    1996-06-01

    This report considers the use of linear models for analyzing data related to reliability and safety issues of the type usually associated with nuclear power plants. The report discusses some of the general results of linear regression analysis, such as the model assumptions and properties of the estimators of the parameters. The results are motivated with examples of operational data. Results about the important case of a linear regression model with one covariate are covered in detail. This case includes analysis of time trends. The analysis is applied with two different sets of time trend data. Diagnostic procedures and tests for the adequacy of the model are discussed. Some related methods such as weighted regression and nonlinear models are also considered. A discussion of the general linear model is also included. Appendix A gives some basic SAS programs and outputs for some of the analyses discussed in the body of the report. Appendix B is a review of some of the matrix theoretic results which are useful in the development of linear models.

  7. New non-linear photovoltaic effect in uniform bipolar semiconductor

    SciTech Connect (OSTI)

    Volovichev, I.

    2014-11-21

    A linear theory of the new non-linear photovoltaic effect in the closed circuit consisting of a non-uniformly illuminated uniform bipolar semiconductor with neutral impurities is developed. The non-uniform photo-excitation of impurities results in the position-dependant current carrier mobility that breaks the semiconductor homogeneity and induces the photo-electromotive force (emf). As both the electron (or hole) mobility gradient and the current carrier generation rate depend on the light intensity, the photo-emf and the short-circuit current prove to be non-linear functions of the incident light intensity at an arbitrarily low illumination. The influence of the sample size on the photovoltaic effect magnitude is studied. Physical relations and distinctions between the considered effect and the Dember and bulk photovoltaic effects are also discussed.

  8. APPLICATION OF NEURAL NETWORK ALGORITHMS FOR BPM LINEARIZATION

    SciTech Connect (OSTI)

    Musson, John C.; Seaton, Chad; Spata, Mike F.; Yan, Jianxun

    2012-11-01

    Stripline BPM sensors contain inherent non-linearities, as a result of field distortions from the pickup elements. Many methods have been devised to facilitate corrections, often employing polynomial fitting. The cost of computation makes real-time correction difficult, particulalry when integer math is utilized. The application of neural-network technology, particularly the multi-layer perceptron algorithm, is proposed as an efficient alternative for electrode linearization. A process of supervised learning is initially used to determine the weighting coefficients, which are subsequently applied to the incoming electrode data. A non-linear layer, known as an ?activation layer,? is responsible for the removal of saturation effects. Implementation of a perceptron in an FPGA-based software-defined radio (SDR) is presented, along with performance comparisons. In addition, efficient calculation of the sigmoidal activation function via the CORDIC algorithm is presented.

  9. Confirming the Lanchestrian linear-logarithmic model of attrition

    SciTech Connect (OSTI)

    Hartley, D.S. III.

    1990-12-01

    This paper is the fourth in a series of reports on the breakthrough research in historical validation of attrition in conflict. Significant defense policy decisions, including weapons acquisition and arms reduction, are based in part on models of conflict. Most of these models are driven by their attrition algorithms, usually forms of the Lanchester square and linear laws. None of these algorithms have been validated. The results of this paper confirm the results of earlier papers, using a large database of historical results. The homogeneous linear-logarithmic Lanchestrian attrition model is validated to the extent possible with current initial and final force size data and is consistent with the Iwo Jima data. A particular differential linear-logarithmic model is described that fits the data very well. A version of Helmbold's victory predicting parameter is also confirmed, with an associated probability function. 37 refs., 73 figs., 68 tabs.

  10. Magnetic levitation configuration incorporating levitation, guidance and linear synchronous motor

    DOE Patents [OSTI]

    Coffey, Howard T. (Darien, IL)

    1993-01-01

    A propulsion and suspension system for an inductive repulsion type magnetically levitated vehicle which is propelled and suspended by a system which includes propulsion windings which form a linear synchronous motor and conductive guideways, adjacent to the propulsion windings, where both combine to partially encircling the vehicle-borne superconducting magnets. A three phase power source is used with the linear synchronous motor to produce a traveling magnetic wave which in conjunction with the magnets propel the vehicle. The conductive guideway combines with the superconducting magnets to provide for vehicle leviation.

  11. Klystron switching power supplies for the Internation Linear Collider

    SciTech Connect (OSTI)

    Fraioli, Andrea; /Cassino U. /INFN, Pisa

    2009-12-01

    The International Linear Collider is a majestic High Energy Physics particle accelerator that will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. ILC will complement the Large Hadron Collider (LHC), a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, by producing electron-positron collisions at center of mass energy of about 500 GeV. In particular, the subject of this dissertation is the R&D for a solid state Marx Modulator and relative switching power supply for the International Linear Collider Main LINAC Radio Frequency stations.

  12. Beamstrahlung spectra in next generation linear colliders. Revision

    SciTech Connect (OSTI)

    Barklow, T.; Chen, P.; Kozanecki, W.

    1992-04-01

    For the next generation of linear colliders, the energy loss due to beamstrahlung during the collision of the e{sup +}e{sup {minus}} beams is expected to substantially influence the effective center-of-mass energy distribution of the colliding particles. In this paper, we first derive analytical formulae for the electron and photon energy spectra under multiple beamstrahlung processes, and for the e{sup +}e{sup {minus}} and {gamma}{gamma} differential luminosities. We then apply our formulation to various classes of 500 GeV e{sup +}e{sup {minus}} linear collider designs currently under study.

  13. Cascaded emission of linearly polarized single photons from positioned

    Office of Scientific and Technical Information (OSTI)

    InP/GaInP quantum dots (Journal Article) | SciTech Connect Cascaded emission of linearly polarized single photons from positioned InP/GaInP quantum dots Citation Details In-Document Search Title: Cascaded emission of linearly polarized single photons from positioned InP/GaInP quantum dots We report on the optical characterization of site-controlled InP/GaInP quantum dots (QDs). Spatially resolved low temperature cathodoluminescence proves the long-range ordering of the buried emitters,

  14. Magnetic levitation configuration incorporating levitation, guidance and linear synchronous motor

    DOE Patents [OSTI]

    Coffey, H.T.

    1993-10-19

    A propulsion and suspension system for an inductive repulsion type magnetically levitated vehicle which is propelled and suspended by a system which includes propulsion windings which form a linear synchronous motor and conductive guideways, adjacent to the propulsion windings, where both combine to partially encircling the vehicle-borne superconducting magnets. A three phase power source is used with the linear synchronous motor to produce a traveling magnetic wave which in conjunction with the magnets propel the vehicle. The conductive guideway combines with the superconducting magnets to provide for vehicle levitation. 3 figures.

  15. Search for Linear Polarization of the Cosmic Background Radiation

    DOE R&D Accomplishments [OSTI]

    Lubin, P. M.; Smoot, G. F.

    1978-10-01

    We present preliminary measurements of the linear polarization of the cosmic microwave background (3 deg K blackbody) radiation. These ground-based measurements are made at 9 mm wavelength. We find no evidence for linear polarization, and set an upper limit for a polarized component of 0.8 m deg K with a 95% confidence level. This implies that the present rate of expansion of the Universe is isotropic to one part in 10{sup 6}, assuming no re-ionization of the primordial plasma after recombination

  16. Scalable Library for the Parallel Solution of Sparse Linear Systems

    Energy Science and Technology Software Center (OSTI)

    1993-07-14

    BlockSolve is a scalable parallel software library for the solution of large sparse, symmetric systems of linear equations. It runs on a variety of parallel architectures and can easily be ported to others. BlockSovle is primarily intended for the solution of sparse linear systems that arise from physical problems having multiple degrees of freedom at each node point. For example, when the finite element method is used to solve practical problems in structural engineering, eachmore » node will typically have anywhere from 3-6 degrees of freedom associated with it. BlockSolve is written to take advantage of problems of this nature; however, it is still reasonably efficient for problems that have only one degree of freedom associated with each node, such as the three-dimensional Poisson problem. It does not require that the matrices have any particular structure other than being sparse and symmetric. BlockSolve is intended to be used within real application codes. It is designed to work best in the context of our experience which indicated that most application codes solve the same linear systems with several different right-hand sides and/or linear systems with the same structure, but different matrix values multiple times.« less

  17. Tunneling control using classical non-linear oscillator

    SciTech Connect (OSTI)

    Kar, Susmita; Bhattacharyya, S. P.

    2014-04-24

    A quantum particle is placed in symmetric double well potential which is coupled to a classical non-linear oscillator via a coupling function. With different spatial symmetry of the coupling and under various controlling fashions, the tunneling of the quantum particle can be enhanced or suppressed, or totally destroyed.

  18. SIMULTANEOUS LINEAR AND CIRCULAR OPTICAL POLARIMETRY OF ASTEROID (4) VESTA

    SciTech Connect (OSTI)

    Wiktorowicz, Sloane J.; Nofi, Larissa A.

    2015-02-10

    From a single 3.8 hr observation of the asteroid (4) Vesta at 13.7 phase angle with the POlarimeter at Lick for Inclination Studies of Hot jupiters 2 (POLISH2) at the Lick Observatory Shane 3 m telescope, we confirm rotational modulation of linear polarization in the B and V bands. We measure the peak-to-peak modulation in the degree of linear polarization to be ?P = (294 35) 10{sup ?6} (ppm) and time-averaged ?P/P = 0.0575 0.0069. After rotating the plane of linear polarization to the scattering plane, asteroidal rotational modulation is detected with 12? confidence and observed solely in Stokes Q/I. POLISH2 simultaneously measures Stokes I, Q, U (linear polarization), and V (circular polarization), but we detect no significant circular polarization with a 1? upper limit of 78 ppm in the B band. Circular polarization is expected to arise from multiple scattering of sunlight by rough surfaces, and it has previously been detected in nearly all other classes of solar system bodies except for asteroids. Subsequent observations may be compared with surface albedo maps from the Dawn Mission, which may allow the identification of compositional variation across the asteroidal surface. These results demonstrate the high accuracy achieved by POLISH2 at the Lick 3 m telescope, which is designed to directly detect scattered light from spatially unresolvable exoplanets.

  19. Translation and integration of numerical atomic orbitals in linear molecules

    SciTech Connect (OSTI)

    Heinsmki, Sami

    2014-02-14

    We present algorithms for translation and integration of atomic orbitals for LCAO calculations in linear molecules. The method applies to arbitrary radial functions given on a numerical mesh. The algorithms are based on pseudospectral differentiation matrices in two dimensions and the corresponding two-dimensional Gaussian quadratures. As a result, multicenter overlap and Coulomb integrals can be evaluated effectively.

  20. Position sensor for linear synchronous motors employing halbach arrays

    DOE Patents [OSTI]

    Post, Richard Freeman

    2014-12-23

    A position sensor suitable for use in linear synchronous motor (LSM) drive systems employing Halbach arrays to create their magnetic fields is described. The system has several advantages over previously employed ones, especially in its simplicity and its freedom from being affected by weather conditions, accumulated dirt, or electrical interference from the LSM system itself.

  1. Linearly Polarized Thermal Emitter for More Efficient Thermophotovoltaic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Devices - Energy Innovation Portal Thermal Solar Thermal Solar Photovoltaic Solar Photovoltaic Industrial Technologies Industrial Technologies Electricity Transmission Electricity Transmission Advanced Materials Advanced Materials Find More Like This Return to Search Linearly Polarized Thermal Emitter for More Efficient Thermophotovoltaic Devices Ames Laboratory Contact AMES About This Technology Technology Marketing Summary Ames Laboratory researchers have developed fabrication methods for

  2. Energy level alignment of self-assembled linear chains of benzenediami...

    Office of Scientific and Technical Information (OSTI)

    Publisher's Accepted Manuscript: Energy level alignment of self-assembled linear chains of ... on March 24, 2017 Prev Next Title: Energy level alignment of self-assembled linear ...

  3. Scalar mesons in three-flavor linear sigma models

    SciTech Connect (OSTI)

    Deirdre Black; Amir H. Fariborz; Sherif Moussa; Salah Nasri; Joseph Schrechter

    2001-09-01

    The three flavor linear sigma model is studied in order to understand the role of possible light scalar mesons in the pi-pi, pi-K and pi-eta elastic scattering channels. The K-matrix prescription is used to unitarize tree-level amplitudes and, with a sufficiently general model, we obtain reasonable ts to the experimental data. The effect of unitarization is very important and leads to the emergence of a nonet of light scalars, with masses below 1 GeV. We compare with a scattering treatment using a more general non-linear sigma model approach and also comment upon how our results t in with the scalar meson puzzle. The latter involves a preliminary investigation of possible mixing between scalar nonets.

  4. FPGA-based Klystron linearization implementations in scope of ILC

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Omet, M.; Michizono, S.; Matsumoto, T.; Miura, T.; Qiu, F.; Chase, B.; Varghese, P.; Schlarb, H.; Branlard, J.; Cichalewski, W.

    2015-01-23

    We report the development and implementation of four FPGA-based predistortion-type klystron linearization algorithms. Klystron linearization is essential for the realization of ILC, since it is required to operate the klystrons 7% in power below their saturation. The work presented was performed in international collaborations at the Fermi National Accelerator Laboratory (FNAL), USA and the Deutsches Elektronen Synchrotron (DESY), Germany. With the newly developed algorithms, the generation of correction factors on the FPGA was improved compared to past algorithms, avoiding quantization and decreasing memory requirements. At FNAL, three algorithms were tested at the Advanced Superconducting Test Accelerator (ASTA), demonstrating a successfulmore » implementation for one algorithm and a proof of principle for two algorithms. Furthermore, the functionality of the algorithm implemented at DESY was demonstrated successfully in a simulation.« less

  5. Linear corotation torques in non-barotropic disks

    SciTech Connect (OSTI)

    Tsang, David

    2014-02-20

    A fully analytic expression for the linear corotation torque to first order in eccentricity for planets in non-barotropic protoplanetary disks is derived, taking into account the effect of disk entropy gradients. This torque formula is applicable to both the co-orbital, corotation torques and the non-co-orbital, corotation torques—for planets in orbits with non-zero eccentricity—in disks where the thermal diffusivity and viscosity are sufficient to maintain the linearity of these interactions. While the co-orbital, corotation torque is important for migration of planets in Type I migration, the non-co-orbital, corotation torque plays an important role in the eccentricity evolution of giant planets that have opened gaps in the disk. The presence of an entropy gradient in the disk can significantly modify the corotation torque in both these cases.

  6. Finite element analyses of a linear-accelerator electron gun

    SciTech Connect (OSTI)

    Iqbal, M. E-mail: muniqbal@ihep.ac.cn; Wasy, A.; Islam, G. U.; Zhou, Z.

    2014-02-15

    Thermo-structural analyses of the Beijing Electron-Positron Collider (BEPCII) linear-accelerator, electron gun, were performed for the gun operating with the cathode at 1000 °C. The gun was modeled in computer aided three-dimensional interactive application for finite element analyses through ANSYS workbench. This was followed by simulations using the SLAC electron beam trajectory program EGUN for beam optics analyses. The simulations were compared with experimental results of the assembly to verify its beam parameters under the same boundary conditions. Simulation and test results were found to be in good agreement and hence confirmed the design parameters under the defined operating temperature. The gun is operating continuously since commissioning without any thermal induced failures for the BEPCII linear accelerator.

  7. Power Saving Optimization for Linear Collider Interaction Region Parameters

    SciTech Connect (OSTI)

    Seryi, Andrei; /SLAC

    2009-10-30

    Optimization of Interaction Region parameters of a TeV energy scale linear collider has to take into account constraints defined by phenomena such as beam-beam focusing forces, beamstrahlung radiation, and hour-glass effect. With those constraints, achieving a desired luminosity of about 2E34 would require use of e{sup +}e{sup -} beams with about 10 MW average power. Application of the 'travelling focus' regime may allow the required beam power to be reduced by at least a factor of two, helping reduce the cost of the collider, while keeping the beamstrahlung energy loss reasonably low. The technique is illustrated for the 500 GeV CM parameters of the International Linear Collider. This technique may also in principle allow recycling the e{sup +}e{sup -} beams and/or recuperation of their energy.

  8. FPGA-based Klystron linearization implementations in scope of ILC

    SciTech Connect (OSTI)

    Omet, M.; Michizono, S.; Varghese, P.; Schlarb, H.; Branlard, J.; Cichalewski, W.

    2015-01-23

    We report the development and implementation of four FPGA-based predistortion-type klystron linearization algorithms. Klystron linearization is essential for the realization of ILC, since it is required to operate the klystrons 7% in power below their saturation. The work presented was performed in international collaborations at the Fermi National Accelerator Laboratory (FNAL), USA and the Deutsches Elektronen Synchrotron (DESY), Germany. With the newly developed algorithms, the generation of correction factors on the FPGA was improved compared to past algorithms, avoiding quantization and decreasing memory requirements. At FNAL, three algorithms were tested at the Advanced Superconducting Test Accelerator (ASTA), demonstrating a successful implementation for one algorithm and a proof of principle for two algorithms. Furthermore, the functionality of the algorithm implemented at DESY was demonstrated successfully in a simulation.

  9. Experimental Evaluation of the Free Piston Engine - Linear Alternator (FPLA).

    SciTech Connect (OSTI)

    Leick, Michael T.; Moses, Ronald W.

    2015-03-01

    This report describes the experimental evaluation of a prototype free piston engine - linear alternator (FPLA) system developed at Sandia National Laboratories. The opposed piston design wa developed to investigate its potential for use in hybrid electric vehicles (HEVs). The system is mechanically simple with two - stroke uniflow scavenging for gas exchange and timed port fuel injection for fuel delivery, i.e. no complex valving. Electrical power is extracted from piston motion through linear alternators wh ich also provide a means for passive piston synchronization through electromagnetic coupling. In an HEV application, this electrical power would be used to charge the batteries. The engine - alternator system was designed, assembled and operated over a 2 - year period at Sandia National Laboratories in Livermore, CA. This report primarily contains a description of the as - built system, modifications to the system to enable better performance, and experimental results from start - up, motoring, and hydrogen combus tion tests.

  10. When linear stability does not exclude nonlinear instability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kevrekidis, P. G.; Pelinovsky, D. E.; Saxena, A.

    2015-05-29

    We describe a mechanism that results in the nonlinear instability of stationary states even in the case where the stationary states are linearly stable. In this study, this instability is due to the nonlinearity-induced coupling of the linearization’s internal modes of negative energy with the continuous spectrum. In a broad class of nonlinear Schrödinger equations considered, the presence of such internal modes guarantees the nonlinear instability of the stationary states in the evolution dynamics. To corroborate this idea, we explore three prototypical case examples: (a) an antisymmetric soliton in a double-well potential, (b) a twisted localized mode in a one-dimensionalmore » lattice with cubic nonlinearity, and (c) a discrete vortex in a two-dimensional saturable lattice. In all cases, we observe a weak nonlinear instability, despite the linear stability of the respective states.« less

  11. Planning under uncertainty solving large-scale stochastic linear programs

    SciTech Connect (OSTI)

    Infanger, G. . Dept. of Operations Research Technische Univ., Vienna . Inst. fuer Energiewirtschaft)

    1992-12-01

    For many practical problems, solutions obtained from deterministic models are unsatisfactory because they fail to hedge against certain contingencies that may occur in the future. Stochastic models address this shortcoming, but up to recently seemed to be intractable due to their size. Recent advances both in solution algorithms and in computer technology now allow us to solve important and general classes of practical stochastic problems. We show how large-scale stochastic linear programs can be efficiently solved by combining classical decomposition and Monte Carlo (importance) sampling techniques. We discuss the methodology for solving two-stage stochastic linear programs with recourse, present numerical results of large problems with numerous stochastic parameters, show how to efficiently implement the methodology on a parallel multi-computer and derive the theory for solving a general class of multi-stage problems with dependency of the stochastic parameters within a stage and between different stages.

  12. SAR processing with non-linear FM chirp waveforms.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2006-12-01

    Nonlinear FM (NLFM) waveforms offer a radar matched filter output with inherently low range sidelobes. This yields a 1-2 dB advantage in Signal-to-Noise Ratio over the output of a Linear FM (LFM) waveform with equivalent sidelobe filtering. This report presents details of processing NLFM waveforms in both range and Doppler dimensions, with special emphasis on compensating intra-pulse Doppler, often cited as a weakness of NLFM waveforms.

  13. Linear plasmoid instability of thin current sheets with shear flow

    SciTech Connect (OSTI)

    Ni Lei; Germaschewski, Kai; Huang Yimin; Sullivan, Brian P.; Yang Hongang; Bhattacharjee, Amitava

    2010-05-15

    This paper presents linear analytical and numerical studies of plasmoid instabilities in the presence of shear flow in high-Lundquist-number plasmas. Analysis demonstrates that the stability problem becomes essentially two dimensional as the stabilizing effects of shear flow become more prominent. Scaling results are presented for the two-dimensional instabilities. An approximate criterion is given for the critical aspect ratio of thin current sheets at which the plasmoid instability is triggered.

  14. New timing system for the Stanford Linear Collider

    SciTech Connect (OSTI)

    Paffrath, L.; Bernstein, D.; Kang, H.; Koontz, R.; Leger, G.; Ross, M.; Pierce, W.; Wilmunder, A.

    1984-11-01

    In order to be able to meet the goals of the Stanford Linear Collider, a much more precise timing system had to be implemented. This paper describes the specification and design of this system, and the results obtained from its use on 1/3 of the SLAC linac. The functions of various elements are described, and a programmable delay unit (PDU) is described in detail.

  15. LINEAR SCANNING METHOD BASED ON THE SAFT COARRAY

    SciTech Connect (OSTI)

    Martin, C. J.; Martinez-Graullera, O.; Romero, D.; Ullate, L. G.; Higuti, R. T.

    2010-02-22

    This work presents a method to obtain B-scan images based on linear array scanning and 2R-SAFT. Using this technique some advantages are obtained: the ultrasonic system is very simple; it avoids the grating lobes formation, characteristic in conventional SAFT; and subaperture size and focussing lens (to compensate emission-reception) can be adapted dynamically to every image point. The proposed method has been experimentally tested in the inspection of CFRP samples.

  16. Linear induction accelerator and pulse forming networks therefor

    DOE Patents [OSTI]

    Buttram, Malcolm T. (Sandia Park, NM); Ginn, Jerry W. (Albuquerque, NM)

    1989-01-01

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities.

  17. Linearity of Climate Response to Increases in Black Carbon Aerosols

    SciTech Connect (OSTI)

    Mahajan, Salil; Evans, Katherine J.; Hack, James J.; Truesdale, John

    2013-04-19

    The impact of absorbing aerosols on global climate are not completely understood. Here, we present results of idealized experiments conducted with the Community Atmosphere Model (CAM4) coupled to a slab ocean model (CAM4-SOM) to simulate the climate response to increases in tropospheric black carbon aerosols (BC) by direct and semi-direct effects. CAM4-SOM was forced with 0, 1x, 2x, 5x and 10x an estimate of the present day concentration of BC while maintaining their estimated present day global spatial and vertical distribution. The top of the atmosphere (TOA) radiative forcing of BC in these experiments is positive (warming) and increases linearly as the BC burden increases. The total semi-direct effect for the 1x experiment is positive but becomes increasingly negative for higher BC concentrations. The global average surface temperature response is found to be a linear function of the TOA radiative forcing. The climate sensitivity to BC from these experiments is estimated to be 0.42 K $ W^{-1} m^{2}$ when the semi-direct effects are accounted for and 0.22 K $ W^{-1} m^{2}$ with only the direct effects considered. Global average precipitation decreases linearly as BC increases, with a precipitation sensitivity to atmospheric absorption of 0.4 $\\%$ $W^{-1}m^{2}$ . The hemispheric asymmetry of BC also causes an increase in southward cross-equatorial heat transport and a resulting northward shift of the inter-tropical convergence zone in the simulations at a rate of 4$^{\\circ}$N $ PW^{-1}$. Global average mid- and high-level clouds decrease, whereas the low-level clouds increase linearly with BC. The increase in marine stratocumulus cloud fraction over the south tropical Atlantic is caused by increased BC-induced diabatic heating of the free troposphere.

  18. Linear Fresnel Technology added to System Advisor Model's Capabilities -

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    News Releases | NREL Linear Fresnel Technology added to System Advisor Model's Capabilities Now utilities can get detailed information on siting, performance and finances February 8, 2012 A promising Concentrating Solar Power (CSP) technology that uses a stationary receiver tube and an array of mirrors mounted near the ground can now be accessed within the System Advisor Model (SAM), which predicts annual energy production, hourly performance and return on investment. The U.S. Department of

  19. Linearly Polarized Thermal Emitter for More Efficient Thermophotovoltaic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Devices - Energy Innovation Portal Solar Thermal Solar Thermal Advanced Materials Advanced Materials Find More Like This Return to Search Linearly Polarized Thermal Emitter for More Efficient Thermophotovoltaic Devices Ames Laboratory Contact AMES About This Technology Technology Marketing Summary Iowa State University and Ames Laboratory researchers have developed fabrication methods for a polarized thermal emitter than can be used to create more efficient thermophotovoltaic devices for

  20. Linear response of tripartite entanglement to infinitesimal noise

    SciTech Connect (OSTI)

    Zhang, Fu-Lin; Chen, Jing-Ling

    2014-10-15

    Recent experimental progress in prolonging the coherence time of a quantum system prompts us to explore the behavior of quantum entanglement at the beginning of the decoherence process. The response of the entanglement under an infinitesimal noise can serve as a signature of the robustness of entangled states. A crucial problem of this topic in multipartite systems is to compute the degree of entanglement in a mixed state. We find a family of global noise in three-qubit systems, which is composed of four W states. Under its influence, the linear response of the tripartite entanglement of a symmetrical three-qubit pure state is studied. A lower bound of the linear response is found to depend completely on the initial tripartite and bipartite entanglement. This result shows that the decay of tripartite entanglement is hastened by the bipartite one. - Highlights: We study a set of W-type noise and its linear effect on symmetric pure states. Its effect on two-qubit entanglement depends only on the initial concurrence. A lower bound of the effect on 3-tangle is found in terms of initial entanglements. We obtain the time of three-tangle sudden death for two families of typical states. These reveal that the bipartite entanglement speeds up the decay of the tripartite one.

  1. Device and method for imaging of non-linear and linear properties of formations surrounding a borehole

    DOE Patents [OSTI]

    Johnson, Paul A; Tencate, James A; Le Bas, Pierre-Yves; Guyer, Robert; Vu, Cung Khac; Skelt, Christopher

    2013-11-05

    In some aspects of the disclosure, a method and an apparatus is disclosed for investigating material surrounding the borehole. The method includes generating a first low frequency acoustic wave within the borehole, wherein the first low frequency acoustic wave induces a linear and a nonlinear response in one or more features in the material that are substantially perpendicular to a radius of the borehole; directing a first sequence of high frequency pulses in a direction perpendicularly with respect to the longitudinal axis of the borehole into the material contemporaneously with the first acoustic wave; and receiving one or more second high frequency pulses at one or more receivers positionable in the borehole produced by an interaction between the first sequence of high frequency pulses and the one or more features undergoing linear and nonlinear elastic distortion due to the first low frequency acoustic wave to investigate the material surrounding the borehole.

  2. PERVASIVE LINEAR POLARIZATION SIGNALS IN THE QUIET SUN

    SciTech Connect (OSTI)

    Bellot Rubio, L. R.; Orozco Suarez, D.

    2012-09-20

    This paper investigates the distribution of linear polarization signals in the quiet-Sun internetwork using ultra-deep spectropolarimetric data. We reduce the noise of the observations as much as is feasible by adding single-slit measurements of the Zeeman-sensitive Fe I 630 nm lines taken by the Hinode spectropolarimeter. The integrated Stokes spectra are employed to determine the fraction of the field of view covered by linear polarization signals. We find that up to 69% of the quiet solar surface at disk center shows Stokes Q or U profiles with amplitudes larger than 0.032% (4.5 times the noise level of 7 Multiplication-Sign 10{sup -5} reached by the longer integrations). The mere presence of linear polarization in most of the quiet Sun implies that the weak internetwork fields must be highly inclined, but we quantify this by inverting those pixels with Stokes Q or U signals well above the noise. This allows for a precise determination of the field inclination, field strength, and field azimuth because the information carried by all four Stokes spectra is used simultaneously. The inversion is performed for 53% of the observed field of view at a noise level of 1.3 Multiplication-Sign 10{sup -4} I{sub c}. The derived magnetic distributions are thus representative of more than half of the quiet-Sun internetwork. Our results confirm the conclusions drawn from previous analyses using mainly Stokes I and V: internetwork fields are very inclined, but except in azimuth they do not seem to be isotropically distributed.

  3. A RECIPE FOR LINEAR COLLIDER FINAL FOCUS SYSTEM DESIGN

    SciTech Connect (OSTI)

    Seryi, Andrei

    2003-05-27

    The design of Final Focus systems for linear colliders is challenging because of the large demagnifications needed to produce nanometer-sized beams at the interaction point. Simple first- and second-order matrix matching have proven insufficient for this task, and minimization of third- and higher-order aberrations is essential. An appropriate strategy is required for the latter to be successful. A recipe for Final Focus design, and a set of computational tools used to implement this approach, are described herein. An example of the use of this procedure is given.

  4. A superconducting focusing solenoid for the neutrino factory linear accelerator

    SciTech Connect (OSTI)

    M.A. Green; V. Lebedev; B.R. Strauss

    2002-03-01

    The proposed superconducting linear accelerator that accelerates muons from 190 MeV to 2.45 GeV will use superconducting solenoids for focusing the muon beam. The accelerator will use superconducting RF cavities. These cavities are very sensitive to stay magnetic field from the focusing magnets. Superconducting solenoids can have large stray fields. This paper describes the 201.25-MHz acceleration system for the neutrino factory. This paper also describes a focusing solenoid that delivers almost no stray field to a neighboring superconducting RF cavity.

  5. Beam Dynamics Design and Simulation in Ion Linear Accelerators (

    Energy Science and Technology Software Center (OSTI)

    2006-08-01

    Orginally, the ray tracing code TRACK has been developed to fulfill the many special requirements for the Rare Isotope Accelerator Facility known as RIA. Since no available beam-dynamics code met all the necessary requirements, modifications to the code TRACK were introduced to allow end-to-end (from the ion souce to the production target) simulations of the RIA machine, TRACK is a general beam-dynamics code and can be applied for the design, commissioning and operation of modernmore » ion linear accelerators and beam transport systems.« less

  6. Physics at the e⁺e⁻ linear collider

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Moortgat-Picka, G.; Kronfeld, A. S.

    2015-08-14

    A comprehensive review of physics at an e⁺e⁻ linear collider in the energy range of √s = 92 GeV–3 TeV is presented in view of recent and expected LHC results, experiments from low-energy as well as astroparticle physics. The report focuses in particular on Higgs-boson, top-quark and electroweak precision physics, but also discusses several models of beyond the standard model physics such as supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analysed as well.

  7. Physics at the e?e? linear collider

    SciTech Connect (OSTI)

    Moortgat-Picka, G.; Kronfeld, A. S.

    2015-08-14

    A comprehensive review of physics at an e?e? linear collider in the energy range of ?s = 92 GeV3 TeV is presented in view of recent and expected LHC results, experiments from low-energy as well as astroparticle physics. The report focuses in particular on Higgs-boson, top-quark and electroweak precision physics, but also discusses several models of beyond the standard model physics such as supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analysed as well.

  8. Entropy-based separation of linear chain molecules by exploiting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    differences in the saturation capacities in cage-type zeolites | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Entropy-based separation of linear chain molecules by exploiting differences in the saturation capacities in cage-type zeolites Previous Next List Rajamani Krishna, Jasper M. van Baten, Sep. Purif. Technol., 76, 325-330 (2011) DOI: 10.1016/j.seppur.2010.10.023 Full-size image (26 K) Abstract: For zeolites such as CHA, LTA, DDR, ERI, AFX, and TSC

  9. Mechanical features of the ATS RFQ linear accelerator

    SciTech Connect (OSTI)

    Wilson, N.G.; Hayward, T.D.; Lind, G.W.

    1983-01-01

    A radio-frequency quadrupole (RFQ) linear accelerator has been constructed and placed in operation on the Los Alamos National Laboratory accelerator test stand (ATS). This accelerator uses an evacuated rf manifold to distribute rf excitation from the 425-MHz rf power supply to the slot-coupled, RFQ vane-cavity, resonator assembly. The RFQ vanes are supported on commercially available copper-plated, linear, resilient C-seals to provide a high-conductivity rf contact that permits aligning and positioning the vanes during tuning, and demounting the vanes for evaluation and modification as necessary. All rf structures are fabricated from stress-relieved, bright-acid copper-plated carbon steel. Measurements made on the accelerator as assembled have demonstrated >8000 vane-cavity Q at the quadrupole's approx. 423.400-MHz accelerating-mode frequency. Operating manifold vacuum of 3 to 6 x 10/sup -8/ torr has been observed after rf conditioning; conditioning required 150 h for stable high-power rf operation. Experience to date has indicated the desirability of modifying the vane rf-contact seat configuration to improve assembly and alignment procedures, improving vane-machining processes to increase vane straightness, installing periodic vane-shorting rings to minimize the effect of dipole modes in the quadrupole accelerating structure,and modifying the waveguide-coupling slot in the manifold to improve forward rf power flow.

  10. Application of GIS in siting of linear facilities

    SciTech Connect (OSTI)

    Gallagher, G.A. III; Heatwole, D.W.; Schmidt, J.A. )

    1993-01-01

    Geographic information systems (GIS) are powerful tools in the analysis and selection of environmentally acceptable corridors for linear facilities, such as roads and utility lines. GIS can serve several functions in corridor siting, including managing and manipulating extensive environmental databases, weighting and compositing data layers to enable spatial analysis for a path of least resistance,'' summarizing statistics for a comparison of alternative corridors, preparing color graphics for presentations and reports, and providing a record of alternative analysis for permitting reviews and legal challenges. In this paper, the authors examine the benefits and limitations of using GIS to site linear facilities, based mainly on their experience in siting a 600-mile natural gas pipeline in Florida. They implemented a phased analytical approach to define acceptable corridors several miles in width and then selected viable routes within the corridors using a magnified scale. This approach resulted in a dynamic siting process which required numerous iterations of analysis. Consequently, their experience has instilled the benefits derived by expending preliminary effort to create macros of the GIS analytical process so that subsequent effort is minimized during numerous iterations of corridor and route refinement.

  11. Automated control of linear constricted plasma source array

    DOE Patents [OSTI]

    Anders, Andre (Albany, CA); Maschwitz, Peter A. (Martinsville, VA)

    2000-01-01

    An apparatus and method for controlling an array of constricted glow discharge chambers are disclosed. More particularly a linear array of constricted glow plasma sources whose polarity and geometry are set so that the contamination and energy of the ions discharged from the sources are minimized. The several sources can be mounted in parallel and in series to provide a sustained ultra low source of ions in a plasma with contamination below practical detection limits. The quality of film along deposition "tracks" opposite the plasma sources can be measured and compared to desired absolute or relative values by optical and/or electrical sensors. Plasma quality can then be adjusted by adjusting the power current values, gas feed pressure/flow, gas mixtures or a combination of some or all of these to improve the match between the measured values and the desired values.

  12. Beam dynamics in a long-pulse linear induction accelerator

    SciTech Connect (OSTI)

    Ekdahl, Carl; Abeyta, Epifanio O; Aragon, Paul; Archuleta, Rita; Cook, Gerald; Dalmas, Dale; Esquibel, Kevin; Gallegos, Robert A; Garnett, Robert; Harrison, James F; Johnson, Jeffrey B; Jacquez, Edward B; Mc Cuistian, Brian T; Montoya, Nicholas A; Nath, Subrato; Nielsen, Kurt; Oro, David; Prichard, Benjamin; Rose, Chris R; Sanchez, Manolito; Schauer, Martin M; Seitz, Gerald; Schulze, Martin; Bender, Howard A; Broste, William B; Carlson, Carl A; Frayer, Daniel K; Johnson, Douglas E; Tom, C Y; Trainham, C; Williams, John; Scarpetti, Raymond; Genoni, Thomas; Hughes, Thomas; Toma, Carsten

    2010-01-01

    The second axis of the Dual Axis Radiography of Hydrodynamic Testing (DARHT) facility produces up to four radiographs within an interval of 1.6 microseconds. It accomplishes this by slicing four micro-pulses out of a long 1.8-kA, 16.5-MeV electron beam pulse and focusing them onto a bremsstrahlung converter target. The long beam pulse is created by a dispenser cathode diode and accelerated by the unique DARHT Axis-II linear induction accelerator (LIA). Beam motion in the accelerator would be a problem for radiography. High frequency motion, such as from beam breakup instability, would blur the individual spots. Low frequency motion, such as produced by pulsed power variation, would produce spot to spot differences. In this article, we describe these sources of beam motion, and the measures we have taken to minimize it.

  13. Generalized space and linear momentum operators in quantum mechanics

    SciTech Connect (OSTI)

    Costa, Bruno G. da

    2014-06-15

    We propose a modification of a recently introduced generalized translation operator, by including a q-exponential factor, which implies in the definition of a Hermitian deformed linear momentum operator p{sup ^}{sub q}, and its canonically conjugate deformed position operator x{sup ^}{sub q}. A canonical transformation leads the Hamiltonian of a position-dependent mass particle to another Hamiltonian of a particle with constant mass in a conservative force field of a deformed phase space. The equation of motion for the classical phase space may be expressed in terms of the generalized dual q-derivative. A position-dependent mass confined in an infinite square potential well is shown as an instance. Uncertainty and correspondence principles are analyzed.

  14. RECENT PROGRESS TOWARD A MUON RECIRCULATING LINEAR ACCELERATOR

    SciTech Connect (OSTI)

    Slawomir Bogacz, Vasiliy Morozov, Yves Roblin, Kevin Beard

    2012-07-01

    Both Neutrino Factories (NF) and Muon Colliders (MC) require very rapid acceleration due to the short lifetime of muons. After a capture and bunching section, a linac raises the energy to about 900 MeV, and is followed by one or more Recirculating Linear Accelerators (RLA), possibly followed by a Rapid Cycling Synchnotron (RCS) or Fixed-Field Alternating Gradient (FFAG) ring. A RLA reuses the expensive RF linac section for a number of passes at the price of having to deal with different energies within the same linac. Various techniques including pulsed focusing quadruopoles, beta frequency beating, and multipass arcs have been investigated via simulations to improve the performance and reduce the cost of such RLAs.

  15. Microgrid Reliability Modeling and Battery Scheduling Using Stochastic Linear Programming

    SciTech Connect (OSTI)

    Cardoso, Goncalo; Stadler, Michael; Siddiqui, Afzal; Marnay, Chris; DeForest, Nicholas; Barbosa-Povoa, Ana; Ferrao, Paulo

    2013-05-23

    This paper describes the introduction of stochastic linear programming into Operations DER-CAM, a tool used to obtain optimal operating schedules for a given microgrid under local economic and environmental conditions. This application follows previous work on optimal scheduling of a lithium-iron-phosphate battery given the output uncertainty of a 1 MW molten carbonate fuel cell. Both are in the Santa Rita Jail microgrid, located in Dublin, California. This fuel cell has proven unreliable, partially justifying the consideration of storage options. Several stochastic DER-CAM runs are executed to compare different scenarios to values obtained by a deterministic approach. Results indicate that using a stochastic approach provides a conservative yet more lucrative battery schedule. Lower expected energy bills result, given fuel cell outages, in potential savings exceeding 6percent.

  16. Intersecting nonextreme p-branes and linear dilaton background

    SciTech Connect (OSTI)

    Chen, C.-M.; Gal'tsov, Dmitri V.; Ohta, Nobuyoshi

    2005-08-15

    We construct the general static solution to the supergravity action containing gravity, the dilaton and a set of antisymmetric forms describing the intersecting branes delocalized in the relative transverse dimensions. The solution is obtained by reducing the system to a set of separate Liouville equations (the intersection rules implying the separability); it contains the maximal number of free parameters corresponding to the rank of the differential equations. Imposing the requirement of the absence of naked singularities, we show that the general configurations are restricted to two and only two classes: the usual asymptotically flat intersecting branes, and the intersecting branes some of which are asymptotically flat and some approach the linear dilaton background at infinity. In both cases the configurations are black. These are supposed to be relevant for the description of the thermal phase of the QFT's in the corresponding Domain-Wall/QFT duality.

  17. Non-linear optical crystal vibration sensing device

    DOE Patents [OSTI]

    Kalibjian, R.

    1994-08-09

    A non-linear optical crystal vibration sensing device including a photorefractive crystal and a laser is disclosed. The laser produces a coherent light beam which is split by a beam splitter into a first laser beam and a second laser beam. After passing through the crystal the first laser beam is counter-propagated back upon itself by a retro-mirror, creating a third laser beam. The laser beams are modulated, due to the mixing effect within the crystal by vibration of the crystal. In the third laser beam, modulation is stable and such modulation is converted by a photodetector into a usable electrical output, intensity modulated in accordance with vibration applied to the crystal. 3 figs.

  18. Separated-orbit bisected energy-recovered linear accelerator

    DOE Patents [OSTI]

    Douglas, David R.

    2015-09-01

    A separated-orbit bisected energy-recovered linear accelerator apparatus and method. The accelerator includes a first linac, a second linac, and a plurality of arcs of differing path lengths, including a plurality of up arcs, a plurality of downgoing arcs, and a full energy arc providing a path independent of the up arcs and downgoing arcs. The up arcs have a path length that is substantially a multiple of the RF wavelength and the full energy arc includes a path length that is substantially an odd half-integer multiple of the RF wavelength. Operation of the accelerator includes accelerating the beam utilizing the linacs and up arcs until the beam is at full energy, at full energy executing a full recirculation to the second linac using a path length that is substantially an odd half-integer of the RF wavelength, and then decelerating the beam using the linacs and downgoing arcs.

  19. Detection of linear impermeable barriers by transient pressure analysis

    SciTech Connect (OSTI)

    Martinez-Romero, N.; Cinco-Ley, H.

    1983-05-01

    This work presents a new simple method to detect a linear impermeable barrier by analysis of transient pressure data. This technique is based on the desuperposition method (negative superposition) discussed by some authors and considers the calculation the pressure change caused by the presence of the barrier. The pressure change is analyzed to estimate the distance between the well and the barrier by using the type curve matching technique. Type curves are provided for both drawdown and build tests. The advantage of the technique presented in this work is that pressure data can be analyzed even if the second semilog straight line, whose slope is twice the slope of the first semilog straight line, is not reached. Examples of application are discussed for illustration.

  20. Phase and Radial Motion in Ion Linear Accelerators

    Energy Science and Technology Software Center (OSTI)

    2007-03-29

    Parmila is an ion-linac particle-dynamics code. The name comes from the phrase, "Phase and Radial Motion in Ion Linear Accelerators." The code generates DTL, CCDTL, and CCL accelerating cells and, using a "drift-kick" method, transforms the beam, represented by a collection of particles, through the linac. The code includes a 2-D and 3-D space-charge calculations. Parmila uses data generated by the Poisson Superfish postprocessor SEC. This version of Parmila was written by Harunori Takeda andmore » was supported through Feb. 2006 by James H. Billen. Setup installs executable programs Parmila.EXE, Lingraf.EXE, and ReadPMI.EXE in the LANL directory. The directory LANL\\Examples\\Parmila contains several subdirectories with sample files for Parmila.« less

  1. ANALYZING SURFACE ROUGHNESS DEPENDENCE OF LINEAR RF LOSSES

    SciTech Connect (OSTI)

    Reece, Charles E.; Kelley, Michael J.; Xu, Chen

    2012-09-01

    Topographic structure on Superconductivity Radio Frequency (SRF) surfaces can contribute additional cavity RF losses describable in terms of surface RF reflectivity and absorption indices of wave scattering theory. At isotropic homogeneous extent, Power Spectrum Density (PSD) of roughness is introduced and quantifies the random surface topographic structure. PSD obtained from different surface treatments of niobium, such Buffered Chemical Polishing (BCP), Electropolishing (EP), Nano-Mechanical Polishing (NMP) and Barrel Centrifugal Polishing (CBP) are compared. A perturbation model is utilized to calculate the additional rough surface RF losses based on PSD statistical analysis. This model will not consider that superconductor becomes normal conducting at fields higher than transition field. One can calculate the RF power dissipation ratio between rough surface and ideal smooth surface within this field range from linear loss mechanisms.

  2. Physics and technology of the next linear collider

    SciTech Connect (OSTI)

    1996-06-01

    The authors present the prospects for the next generation of high-energy physics experiments with electron-positron colliding beams. This report summarizes the current status of the design and technological basis of a linear collider of center-of-mass energy 0.5--1.5 TeV, and the opportunities for high-energy physics experiments that this machine is expected to open. The physics goals discussed here are: Standard Model processes and simulation; top quark physics; Higgs boson searches and properties; supersymmetry; anomalous gauge boson couplings; strong WW scattering; new gauge bosons and exotic particles; e{sup {minus}}e{sup {minus}}, e{sup {minus}}{gamma}, and {gamma}{gamma} interactions; and precision tests of QCD.

  3. Light-operated proximity detector with linear output

    DOE Patents [OSTI]

    Simpson, M.L.; McNeilly, D.R.

    1984-01-01

    A light-operated proximity detector is described in which reflected light intensity from a surface whose proximity to the detector is to be gauged is translated directly into a signal proportional to the distance of the detector from the surface. A phototransistor is used to sense the reflected light and is connected in a detector circuit which maintains the phtotransistor in a saturated state. A negative feedback arrangement using an operational amplifier connected between the collector and emitter of the transistor provides an output at the output of the amplifier which is linearly proportional to the proximity of the surface to the detector containing the transistor. This direct proportional conversion is true even though the light intensity is varying with the proximity in proportion to the square of the inverse of the distance. The detector may be used for measuring the distance remotely from any target surface.

  4. Light-operated proximity detector with linear output

    DOE Patents [OSTI]

    Simpson, Marc L. (Harriman, TN); McNeilly, David R. (Maryville, TN)

    1985-01-01

    A light-operated proximity detector is described in which reflected light intensity from a surface whose proximity to the detector is to be gauged is translated directly into a signal proportional to the distance of the detector from the surface. A phototransistor is used to sense the reflected light and is connected in a detector circuit which maintains the phototransistor in a saturated state. A negative feedback arrangement using an operational amplifier connected between the collector and emitter of the transistor provides an output at the output of the amplifier which is linearly proportional to the proximity of the surface to the detector containing the transistor. This direct proportional conversion is true even though the light intensity is varying with the proximity in proportion to the square of the inverse of the distance. The detector may be used for measuring the distance remotely from any target surface.

  5. Extreme hydrogen plasma densities achieved in a linear plasma generator

    SciTech Connect (OSTI)

    Rooij, G. J. van; Veremiyenko, V. P.; Goedheer, W. J.; de Groot, B.; Kleyn, A. W.; Smeets, P. H. M.; Versloot, T. W.; Whyte, D. G.; Engeln, R.; Schram, D. C.; Cardozo, N. J. Lopes

    2007-03-19

    A magnetized hydrogen plasma beam was generated with a cascaded arc, expanding in a vacuum vessel at an axial magnetic field of up to 1.6 T. Its characteristics were measured at a distance of 4 cm from the nozzle: up to a 2 cm beam diameter, 7.5x10{sup 20} m{sup -3} electron density, {approx}2 eV electron and ion temperatures, and 3.5 km/s axial plasma velocity. This gives a 2.6x10{sup 24} H{sup +} m{sup -2} s{sup -1} peak ion flux density, which is unprecedented in linear plasma generators. The high efficiency of the source is obtained by the combined action of the magnetic field and an optimized nozzle geometry. This is interpreted as a cross-field return current that leads to power dissipation in the beam just outside the source.

  6. Acoustic methods to monitor sliver linear density and yarn strength

    DOE Patents [OSTI]

    Sheen, Shuh-Haw (Naperville, IL); Chien, Hual-Te (Naperville, IL); Raptis, Apostolos C. (Downers Grove, IL)

    1997-01-01

    Methods and apparatus are provided for monitoring sliver and yarn characteristics. Transverse waves are generated relative to the sliver or yarn. At least one acoustic sensor is in contact with the sliver or yarn for detecting waves coupled to the sliver or yarn and for generating a signal. The generated signal is processed to identify the predefined characteristics including sliver or yarn linear density. The transverse waves can be generated with a high-powered acoustic transmitter spaced relative to the sliver or yarn with large amplitude pulses having a central frequency in a range between 20 KHz and 40 KHz applied to the transmitter. The transverse waves can be generated by mechanically agitating the sliver or yarn with a tapping member.

  7. Non-linear optical crystal vibration sensing device

    DOE Patents [OSTI]

    Kalibjian, Ralph (Livermore, CA)

    1994-01-11

    A non-linear optical crystal vibration sensing device (10) including a photorefractive crystal (26) and a laser (12). The laser (12 ) produces a coherent light beam (14) which is split by a beam splitter (18) into a first laser beam (20) and a second laser beam (22). After passing through the crystal (26) the first laser beam (20) is counter-propagated back upon itself by a retro-mirror (32), creating a third laser beam (30). The laser beams (20, 22, 30) are modulated, due to the mixing effect within the crystal (26) by vibration of the crystal (30). In the third laser beam (30), modulation is stable and such modulation is converted by a photodetector (34) into a usable electrical output, intensity modulated in accordance with vibration applied to the crystal (26).

  8. IR OPTICS MEASUREMENT WITH LINEAR COUPLING'S ACTION-ANGLE PARAMETERIZATION.

    SciTech Connect (OSTI)

    LUO, Y.; BAI, M.; PILAT, R.; SATOGATA, T.; TRBOJEVIC, D.

    2005-05-16

    A parameterization of linear coupling in action-angle coordinates is convenient for analytical calculations and interpretation of turn-by-turn (TBT) beam position monitor (BPM) data. We demonstrate how to use this parameterization to extract the twiss and coupling parameters in interaction regions (IRs), using BPMs on each side of the long IR drift region. The example of TBT BPM analysis was acquired at the Relativistic Heavy Ion Collider (RHIC), using an AC dipole to excite a single eigenmode. Besides the full treatment, a fast estimate of beta*, the beta function at the interaction point (IP), is provided, along with the phase advance between these BPMs. We also calculate and measure the waist of the beta function and the local optics.

  9. A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory...

    Office of Scientific and Technical Information (OSTI)

    A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to Multi-TeV Citation Details In-Document Search Title: A Beam Driven Plasma-Wakefield Linear Collider: From...

  10. Text-Alternative Version: CALiPER Series 21 on LED Linear Lamps...

    Energy Savers [EERE]

    Information Resources Videos Text-Alternative Version: CALiPER Series 21 on LED Linear Lamps and Troffer Lighting Text-Alternative Version: CALiPER Series 21 on LED Linear ...

  11. Linear Dichroism in Resonant Inelastic X-Ray Scattering to Molecular...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Linear Dichroism in Resonant Inelastic X-Ray Scattering to Molecular Spin-Orbit States Linear Dichroism in Resonant Inelastic X-Ray Scattering to Molecular Spin-Orbit States Print...

  12. Environmental Survey preliminary report, Stanford Linear Accelerator Center, Stanford, California

    SciTech Connect (OSTI)

    Not Available

    1988-07-01

    This report presents the preliminary findings from the first phase of the Survey of the US Department of Energy (DOE) Stanford Linear Accelerator Center (SLAC) at Stanford, California, conducted February 29 through March 4, 1988. The Survey is being conducted by an interdisciplinary team of environmental specialists, led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual team components are being supplied by a private contractor. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with the SLAC. The Survey covers all environmental media and all areas of environmental regulation and is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations at the SLAC, and interviews with site personnel. The Survey team is developing a Sampling and Analysis Plan to assist in further assessing certain of the environmental problems identified during its on-site activities. The Sampling and Analysis Plan will be executed by a DOE National Laboratory or a support contractor. When completed, the results will be incorporated into the Environmental Survey Interim Report for the SLAC facility. The Interim Report will reflect the final determinations of the SLAC Survey. 95 refs., 25 figs., 25 tabs.

  13. Towards reversible basic linear algebra subprograms: A performance study

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Perumalla, Kalyan S.; Yoginath, Srikanth B.

    2014-12-06

    Problems such as fault tolerance and scalable synchronization can be efficiently solved using reversibility of applications. Making applications reversible by relying on computation rather than on memory is ideal for large scale parallel computing, especially for the next generation of supercomputers in which memory is expensive in terms of latency, energy, and price. In this direction, a case study is presented here in reversing a computational core, namely, Basic Linear Algebra Subprograms, which is widely used in scientific applications. A new Reversible BLAS (RBLAS) library interface has been designed, and a prototype has been implemented with two modes: (1) amore » memory-mode in which reversibility is obtained by checkpointing to memory in forward and restoring from memory in reverse, and (2) a computational-mode in which nothing is saved in the forward, but restoration is done entirely via inverse computation in reverse. The article is focused on detailed performance benchmarking to evaluate the runtime dynamics and performance effects, comparing reversible computation with checkpointing on both traditional CPU platforms and recent GPU accelerator platforms. For BLAS Level-1 subprograms, data indicates over an order of magnitude better speed of reversible computation compared to checkpointing. For BLAS Level-2 and Level-3, a more complex tradeoff is observed between reversible computation and checkpointing, depending on computational and memory complexities of the subprograms.« less

  14. Numerical simulation of linear fiction welding (LFW) processes

    SciTech Connect (OSTI)

    Fratini, L.; La Spisa, D. [University of Palermo-Dept. of Industrial engineering (Italy)

    2011-05-04

    Solid state welding processes are becoming increasingly important due to a large number of advantages related to joining ''unweldable'' materials and in particular light weight alloys. Linear friction welding (LFW) has been used successfully to bond non-axisymmetric components of a range of materials including titanium alloys, steels, aluminum alloys, nickel, copper, and also dissimilar material combinations. The technique is useful in the research of quality of the joints and in reducing costs of components and parts of the aeronautic and automotive industries.LFW involves parts to be welded through the relative reciprocating motion of two components under an axial force. In such process the heat source is given by the frictional forces work decaying into heat determining a local softening of the material and proper bonding conditions due to both the temperature increase and the local pressure of the two edges to be welded. This paper is a comparative test between the numerical model in two dimensions, i.e. in plane strain conditions, and in three dimensions of a LFW process of AISI1045 steel specimens. It must be observed that the 3D model assures a faithful simulation of the actual threedimensional material flow, even if the two-dimensional simulation computational times are very short, a few hours instead of several ones as the 3D model. The obtained results were compared with experimental values found out in the scientific literature.

  15. Comparative study of medium damped and detuned linear accelerator structures

    SciTech Connect (OSTI)

    Jean-Francois Ostiguy et al.

    2001-08-22

    Long range wakefields are a serious concern for a future linear collider based on room temperature accelerating structures. They can be suppressed either by detuning and or local damping or with some combination of both strategies. Detuning relies on precisely phasing the contributions of the dipole modes excited by the passage of a single bunch. This is accomplished by controlling individual mode frequencies, a process which dictates individual cell dimensional tolerances. Each mode must be excited with the correct strength; this in turn, determines cell-to-cell alignment tolerances. In contrast, in a locally damped structure, the modes are attenuated at the cell level. Clearly, mode frequencies and relative excitation become less critical in that context; mechanical fabrication tolerances can be relaxed. While local damping is ideal from the stand-point of long range wakefield suppression, this comes at the cost of reducing the shunt impedance and possibly unacceptable localized heating. Recently, the Medium Damped Structure (MDS), a compromise between detuning and local damping, has generated some interest. In this paper, we compare a hypothetical MDS to the NLC Rounded Damped Detuned Structure (RDDS) and investigate possible advantages from the standpoint fabrication tolerances and their relation to beam stability and emittance preservation.

  16. Systematic study of doping dependence on linear magnetoresistance in p-PbTe

    SciTech Connect (OSTI)

    Schneider, J. M.; Chitta, V. A.; Oliveira, N. F.; Peres, M. L. Castro, S. de; Soares, D. A. W.; Wiedmann, S.; Zeitler, U.; Abramof, E.; Rappl, P. H. O.; Mengui, U. A.

    2014-10-20

    We report on a large linear magnetoresistance effect observed in doped p-PbTe films. While undoped p-PbTe reveals a sublinear magnetoresistance, p-PbTe films doped with BaF{sub 2} exhibit a transition to a nearly perfect linear magnetoresistance behaviour that is persistent up to 30?T. The linear magnetoresistance slope ?R/?B is to a good approximation, independent of temperature. This is in agreement with the theory of Quantum Linear Magnetoresistance. We also performed magnetoresistance simulations using a classical model of linear magnetoresistance. We found that this model fails to explain the experimental data. A systematic study of the doping dependence reveals that the linear magnetoresistance response has a maximum for small BaF{sub 2} doping levels and diminishes rapidly for increasing doping levels. Exploiting the huge impact of doping on the linear magnetoresistance signal could lead to new classes of devices with giant magnetoresistance behavior.

  17. Linear relationship between water wetting behavior and microscopic interactions of super-hydrophilic surfaces

    SciTech Connect (OSTI)

    Liu, Jian; Guo, Pan; University of Chinese Academy of Sciences, Beijing 100049 ; Wang, Chunlei; Shi, Guosheng Fang, Haiping

    2013-12-21

    Using molecular dynamics simulations, we show a fine linear relationship between surface energies and microscopic Lennard-Jones parameters of super-hydrophilic surfaces. The linear slope of the super-hydrophilic surfaces is consistent with the linear slope of the super-hydrophobic, hydrophobic, and hydrophilic surfaces where stable water droplets can stand, indicating that there is a universal linear behavior of the surface energies with the water-surface van der Waals interaction that extends from the super-hydrophobic to super-hydrophilic surfaces. Moreover, we find that the linear relationship exists for various substrate types, and the linear slopes of these different types of substrates are dependent on the surface atom density, i.e., higher surface atom densities correspond to larger linear slopes. These results enrich our understanding of water behavior on solid surfaces, especially the water wetting behaviors on uncharged super-hydrophilic metal surfaces.

  18. Performance Models for the Spike Banded Linear System Solver

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Manguoglu, Murat; Saied, Faisal; Sameh, Ahmed; Grama, Ananth

    2011-01-01

    With availability of large-scale parallel platforms comprised of tens-of-thousands of processors and beyond, there is significant impetus for the development of scalable parallel sparse linear system solvers and preconditioners. An integral part of this design process is the development of performance models capable of predicting performance and providing accurate cost models for the solvers and preconditioners. There has been some work in the past on characterizing performance of the iterative solvers themselves. In this paper, we investigate the problem of characterizing performance and scalability of banded preconditioners. Recent work has demonstrated the superior convergence properties and robustness of banded preconditioners,more » compared to state-of-the-art ILU family of preconditioners as well as algebraic multigrid preconditioners. Furthermore, when used in conjunction with efficient banded solvers, banded preconditioners are capable of significantly faster time-to-solution. Our banded solver, the Truncated Spike algorithm is specifically designed for parallel performance and tolerance to deep memory hierarchies. Its regular structure is also highly amenable to accurate performance characterization. Using these characteristics, we derive the following results in this paper: (i) we develop parallel formulations of the Truncated Spike solver, (ii) we develop a highly accurate pseudo-analytical parallel performance model for our solver, (iii) we show excellent predication capabilities of our model – based on which we argue the high scalability of our solver. Our pseudo-analytical performance model is based on analytical performance characterization of each phase of our solver. These analytical models are then parameterized using actual runtime information on target platforms. An important consequence of our performance models is that they reveal underlying performance bottlenecks in both serial and parallel formulations. All of our results are validated on diverse heterogeneous multiclusters – platforms for which performance prediction is particularly challenging. Finally, we provide predict the scalability of the Spike algorithm using up to 65,536 cores with our model. In this paper we extend the results presented in the Ninth International Symposium on Parallel and Distributed Computing.« less

  19. Linearization of scan velocity of resonant vibrating-mirror beam deflectors

    DOE Patents [OSTI]

    Yeung, E.S.; Chen, S.L.

    1991-01-15

    A means and method for producing linearization of scan velocity of resonant vibrating-mirror beam deflectors in laser scanning system including presenting an elliptical convex surface to the scanning beam to reflect the scanning beam to the focal plane of the scanning line. The elliptical surface is shaped to produce linear velocity of the reflective scanning beam at the focal plane. Maximization of linearization is accomplished by considering sets of criteria for different scanning applications. 6 figures.

  20. Knot Undulator to Generate Linearly Polarized Photons with Low on-Axis

    Office of Scientific and Technical Information (OSTI)

    Power Density (Technical Report) | SciTech Connect Technical Report: Knot Undulator to Generate Linearly Polarized Photons with Low on-Axis Power Density Citation Details In-Document Search Title: Knot Undulator to Generate Linearly Polarized Photons with Low on-Axis Power Density Heat load on beamline optics is a serious problem to generate pure linearly polarized photons in the third generation synchrotron radiation facilities. For permanent magnet undulators, this problem can be overcome

  1. Depolarization due to beam-beam interaction in electron-positron linear

    Office of Scientific and Technical Information (OSTI)

    colliders (Conference) | SciTech Connect Conference: Depolarization due to beam-beam interaction in electron-positron linear colliders Citation Details In-Document Search Title: Depolarization due to beam-beam interaction in electron-positron linear colliders We investigate two major mechanisms which induce depolarization of electron beams during beam-beam interaction in linear colliders. These are the classical spin precession under the collective field of the oncoming beam, and the

  2. Results from a Prototype Chicane-Based Energy Spectrometer for a Linear

    Office of Scientific and Technical Information (OSTI)

    Collider (Journal Article) | SciTech Connect Results from a Prototype Chicane-Based Energy Spectrometer for a Linear Collider Citation Details In-Document Search Title: Results from a Prototype Chicane-Based Energy Spectrometer for a Linear Collider The International Linear Collider (ILC) and other proposed high energy e{sup +}e{sup -} machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered phenomena. One of the main requirements for

  3. Text-Alternative Version: CALiPER Series 21 on LED Linear Lamps and Troffer

    Energy Savers [EERE]

    Lighting | Department of Energy Information Resources » Videos » Text-Alternative Version: CALiPER Series 21 on LED Linear Lamps and Troffer Lighting Text-Alternative Version: CALiPER Series 21 on LED Linear Lamps and Troffer Lighting Following is a text version of a video about CALiPER Application Report Series 21 on LED Linear Lamps and Troffer Lighting. Tracy Beeson, Lighting Engineer, Pacific Northwest National Laboratory: Fluorescent troffers are widely used in office spaces, meeting

  4. Type A Investigation of the Electrical Arc Injury at the Stanford Linear

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Accelerator Complex on October 11, 2004 | Department of Energy of the Electrical Arc Injury at the Stanford Linear Accelerator Complex on October 11, 2004 Type A Investigation of the Electrical Arc Injury at the Stanford Linear Accelerator Complex on October 11, 2004 November 15, 2004 On October 11, 2004, at approximately 11:15 am, a subcontractor electrician working at the Stanford Linear Accelerator Center (SLAC) received serious burn injuries requiring hospitalization due to an electrical

  5. Photo of the Week: Lego Rendition of SLAC National Laboratory's Linear

    Energy Savers [EERE]

    Particle Accelerator | Department of Energy Lego Rendition of SLAC National Laboratory's Linear Particle Accelerator Photo of the Week: Lego Rendition of SLAC National Laboratory's Linear Particle Accelerator February 4, 2013 - 10:26am Addthis At two miles long, SLAC's linear particle accelerator is a monster of a machine. But now, thanks to an old collection of Legos and some creative work by SLAC graphic designer Greg Stewart, the two-mile accelerator has been drastically reduced in size.

  6. Quantum chaos of an ion trapped in a linear ion trap (Journal Article) |

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Quantum chaos of an ion trapped in a linear ion trap Citation Details In-Document Search Title: Quantum chaos of an ion trapped in a linear ion trap We describe the transition to quantum chaos of an ion trapped in a linear ion trap and interacting with two laser fields. Under the conditions of adiabatic illumination of the upper level of the ion, and when the frequencies of the two laser beams are slightly different, the system is reduced to a quantum linear oscillator

  7. Non-Linear Luminescent Coupling in Series-Connected Multijunction Solar Cells

    SciTech Connect (OSTI)

    Steiner, M. A.; Geisz, J. F.

    2012-06-18

    The assumption of superposition or linearity of photocurrent with solar flux is widespread for calculations and measurements of solar cells. The well-known effect of luminescent coupling in multijunction solar cells has also been assumed to be linear with excess current. Here we show significant non-linearities in luminescent coupling in III-V multijunction solar cells and propose a simple model based on competition between radiative and nonradiative processes in the luminescent junction to explain these non-linearities. We demonstrate a technique for accurately measuring the junction photocurrents under a specified reference spectrum, that accounts for and quantifies luminescent coupling effects.

  8. 2011 Annual Planning Summary for Stanford Linear Accelerator Center Site Office (SLAC)

    Broader source: Energy.gov [DOE]

    The ongoing and projected Environmental Assessments and Environmental Impact Statements for 2011 and 2012 within the Stanford Linear Accelerator Center Site Office (SLAC SO) (See also Science).

  9. LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21

    SciTech Connect (OSTI)

    Beeson, Tracy; Miller, Naomi

    2014-06-17

    Video about CALiPER Report Series 21 on LED Linear Lamps and Troffer Lighting, featuring interviews with Tracy Beeson and Naomi Miller of Pacific Northwest National Laboratory.

  10. LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21

    ScienceCinema (OSTI)

    Beeson, Tracy; Miller, Naomi

    2014-06-23

    Video about CALiPER Report Series 21 on LED Linear Lamps and Troffer Lighting, featuring interviews with Tracy Beeson and Naomi Miller of Pacific Northwest National Laboratory.

  11. Linear Collider LHC Subpanel | U.S. DOE Office of Science (SC...

    Office of Science (SC) Website

    Subpanel on the Linear Collider and the Large Hadron Collider High Energy Physics Advisory Panel (HEPAP) HEPAP Home Meetings 2015 HEPAP Membership ChargesReports Charter .pdf file ...

  12. Tuning the DARHT Axis-II linear induction accelerator focusing

    SciTech Connect (OSTI)

    Ekdahl, Carl A.

    2012-04-24

    Flash radiography of large hydrodynamic experiments driven by high explosives is a well-known diagnostic technique in use at many laboratories, and the Dual-Axis Radiography for Hydrodynamic Testing (DARHT) facility at Los Alamos produces flash radiographs of large hydrodynamic experiments. Two linear induction accelerators (LIAs) make the bremsstrahlung radiographic source spots for orthogonal views of each test. The 2-kA, 20-MeV Axis-I LIA creates a single 60-ns radiography pulse. The 1.7-kA, 16.5-MeV Axis-II LIA creates up to four radiography pulses by kicking them out of a longer pulse that has a 1.6-{mu}s flattop. The Axis-II injector, LIA, kicker, and downstream transport (DST) to the bremsstrahlung converter are described. Adjusting the magnetic focusing and steering elements to optimize the electron-beam transport through an LIA is often called 'tuning.' As in all high-current LIAs, the focusing field is designed to be as close to that of the ideal continuous solenoid as physically possible. In ideal continuous solenoidal transport a smoothly varying beam size can easily be found for which radial forces balance, and the beam is said to be 'matched' to the focusing field. A 'mismatched' beam exhibits unwanted oscillations in size, which are a source of free energy that contributes to emittance growth. This is undesirable, because in the absence of beam-target effects, the radiographic spot size is proportional to the emittance. Tuning the Axis-II LIA is done in two steps. First, the solenoidal focusing elements are set to values designed to provide a matched beam with little or no envelope oscillations, and little or no beam-breakup (BBU) instability growth. Then, steering elements are adjusted to minimize the motion of the centroid of a well-centered beam at the LIA exit. This article only describes the design of the tune for the focusing solenoids. The DARHT Axis-II LIA was required to be re-tuned after installing an accelerator cell to replace a failed solenoid in March of 2012. We took advantage of this opportunity to improve the design of the focusing tune with better models of the remaining partially failed solenoids, better estimates of beam initial conditions, and better values for pulsed-power voltages. As with all previous tunes for Axis-II, this one incorporates measures to mitigate beam-breakup (BBU) instability, image displacement instability (IDI), corkscrew (sweep), and emittance growth. Section II covers the general approach to of design of focusing solenoid tunes for the DARHT Axis-2 LIA. Section III explains the specific requirements and simulations needed to design the tune for the injector, which includes the thermionic electron source, diode, and six induction cells. Section IV explains the requirements and simulations for tuning the main accelerator, which consists of 68 induction cells. Finally, Section V explores sensitivity of the tune to deviations of parameters from nominal, random variations, and uncertainties in values. Four appendices list solenoid settings for this new tune, discuss comparisons of different simulation codes, show halo formation in mismatched beams, and present a brief discussion of the beam envelope equation, which is the heart of the method used to design LIA solenoid tunes.

  13. Proceedings of the Oak Ridge Electron Linear Accelerator (ORELA) Workshop

    SciTech Connect (OSTI)

    Dunn, M.E.

    2006-02-27

    The Oak Ridge National Laboratory (ORNL) organized a workshop at ORNL July 14-15, 2005, to highlight the unique measurement capabilities of the Oak Ridge Electron Linear Accelerator (ORELA) facility and to emphasize the important role of ORELA for performing differential cross-section measurements in the low-energy resonance region that is important for nuclear applications such as nuclear criticality safety, nuclear reactor and fuel cycle analysis, stockpile stewardship, weapons research, medical diagnosis, and nuclear astrophysics. The ORELA workshop (hereafter referred to as the Workshop) provided the opportunity to exchange ideas and information pertaining to nuclear cross-section measurements and their importance for nuclear applications from a variety of perspectives throughout the U.S. Department of Energy (DOE). Approximately 50 people, representing DOE, universities, and seven U.S. national laboratories, attended the Workshop. The objective of the Workshop was to emphasize the technical community endorsement for ORELA in meeting nuclear data challenges in the years to come. The Workshop further emphasized the need for a better understanding of the gaps in basic differential nuclear measurements and identified the efforts needed to return ORELA to a reliable functional measurement facility. To accomplish the Workshop objective, nuclear data experts from national laboratories and universities were invited to provide talks emphasizing the unique and vital role of the ORELA facility for addressing nuclear data needs. ORELA is operated on a full cost-recovery basis with no single sponsor providing complete base funding for the facility. Consequently, different programmatic sponsors benefit by receiving accurate cross-section data measurements at a reduced cost to their respective programs; however, leveraging support for a complex facility such as ORELA has a distinct disadvantage in that the programmatic funds are only used to support program-specific measurements. As a result, ORELA has not received base funding to support major upgrades and significant maintenance operations that are essential to keep the facility in a state of readiness over the long term. As a result, ORELA has operated on a ''sub-bare-minimum'' budget for the past 10 to 15 years, and the facility has not been maintained at a level for continued reliable operation for the long term. During the Workshop, Jerry McKamy (NNSA/NA-117) used a hospital patient metaphor that accurately depicts the facility status. ORELA is currently in the intensive care unit (ICU) on life support, and refurbishment efforts are needed to get the ''patient'' off life support and out to an ordinary hospital room. McKamy further noted that the DOE NCSP is planning to fund immediate refurbishment tasks ($1.5 M over three years) to help reestablish reliable ORELA operation (i.e., move ORELA from ICU to an ordinary hospital room). Furthermore, the NCSP will work to identify and carry out the actions needed to discharge ORELA from the ''hospital'' over the next five to seven years. In accordance with the Workshop objectives, the technical community publicly endorsed the need for a reliable ORELA facility that can meet current and future nuclear data needs. These Workshop proceedings provide the formal documentation of the technical community endorsement for ORELA. Furthermore, the proceedings highlight the past and current contributions that ORELA has made to the nuclear industry. The Workshop further emphasized the operational and funding problems that currently plague the facility, thereby limiting ORELA's operational reliability. Despite the recent operational problems, ORELA is a uniquely capable measurement facility that must be part of the overall U.S. nuclear data measurement portfolio in order to support current and emerging nuclear applications. The Workshop proceedings further emphasize that ORNL, the technical community, and programmatic sponsors are eager to see ORELA reestablish reliable measurement operation and be readily available to address nuclear data challe

  14. DOE Publishes CALiPER Report on Linear (T8) LED Lamps in Recessed Troffers

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 21.2, which is part of a series of investigations on linear LED lamps. Report 21.2 focuses on the performance of three linear (T8...

  15. Project Profile: Commercial Development of an Advanced Linear-Fresnel-Based CSP Concept

    Broader source: Energy.gov [DOE]

    SkyFuel, under the CSP R&D FOA, is developing a commercial linear-Fresnel-based advanced CSP system called Linear Power Tower (LPT). The company aims to make significant improvements in the cost and viability of utility-scale dispatchable solar power.

  16. System and method for linearly amplifying optical analog signals by backward Raman scattering

    DOE Patents [OSTI]

    Lin, Cheng-Heui (Goleta, CA)

    1988-01-01

    A system for linearly amplifying an optical analog signal by backward stimulated Raman scattering comprises a laser source for generating a pump pulse; and an optic fiber having two opposed apertures, a first aperture for receiving the pump pulse and a second aperture for receiving the optical analog signal, wherein the optical analog signal is linearly amplified to an amplified optical analog signal.

  17. Results and Comparison from the SAM Linear Fresnel Technology Performance Model: Preprint

    SciTech Connect (OSTI)

    Wagner, M. J.

    2012-04-01

    This paper presents the new Linear Fresnel technology performance model in NREL's System Advisor Model. The model predicts the financial and technical performance of direct-steam-generation Linear Fresnel power plants, and can be used to analyze a range of system configurations. This paper presents a brief discussion of the model formulation and motivation, and provides extensive discussion of the model performance and financial results. The Linear Fresnel technology is also compared to other concentrating solar power technologies in both qualitative and quantitative measures. The Linear Fresnel model - developed in conjunction with the Electric Power Research Institute - provides users with the ability to model a variety of solar field layouts, fossil backup configurations, thermal receiver designs, and steam generation conditions. This flexibility aims to encompass current market solutions for the DSG Linear Fresnel technology, which is seeing increasing exposure in fossil plant augmentation and stand-alone power generation applications.

  18. Efficient Algorithms for Estimating the Absorption Spectrum within Linear Response TDDFT

    SciTech Connect (OSTI)

    Brabec, Jiri; Lin, Lin; Shao, Meiyue; Govind, Niranjan; Yang, Chao; Saad, Yousef; Ng, Esmond

    2015-10-06

    We present two iterative algorithms for approximating the absorption spectrum of molecules within linear response of time-dependent density functional theory (TDDFT) framework. These methods do not attempt to compute eigenvalues or eigenvectors of the linear response matrix. They are designed to approximate the absorption spectrum as a function directly. They take advantage of the special structure of the linear response matrix. Neither method requires the linear response matrix to be constructed explicitly. They only require a procedure that performs the multiplication of the linear response matrix with a vector. These methods can also be easily modified to efficiently estimate the density of states (DOS) of the linear response matrix without computing the eigenvalues of this matrix. We show by computational experiments that the methods proposed in this paper can be much more efficient than methods that are based on the exact diagonalization of the linear response matrix. We show that they can also be more efficient than real-time TDDFT simulations. We compare the pros and cons of these methods in terms of their accuracy as well as their computational and storage cost.

  19. A linear MOSFET regulator for improving performance of the booster ramping power supplies at the APS.

    SciTech Connect (OSTI)

    Feng, G.; Deriy, B.; Wang, J.; Accelerator Systems Division

    2008-01-01

    The APS booster ring uses ramping power supplies to power the sextupole, quadrupole, and dipole magnets as the beam energy ramps up linearly to 7 GeV. Due to the circuit topology used, those supplies are unable to follow the linear ramp to the desired accuracy. The best regulation achieved is 0.25% while 0.1% is desired. In addition to the unsatisfying regulation, those supplies are sensitive to AC line perturbation and are not able to reject AC line noises of more than a few tens of hertz. To improve the performance, a linear MOSFET regulation system using paralleled MOSFET devices in series with the power supply is proposed. The system uses a realtime current feedback loop to force the MOSFETs to work in the linear operation mode. By using this linear MOSFET regulator, the voltage drop on MOSFETs, and hence the voltage imposed on magnets, can be regulated very quickly. As a result, the regulation of the magnet current can be improved significantly. So far the simulation results show that with the linear regulator, the current regulation can be improved to better than 0.1%. Because of the high bandwidth of the linear regulator, it can reduce the harmonic content in the output current as well as reject the AC line disturbance. This paper discusses the circuit topology, the regulation method, and the simulation results.

  20. LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21 |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Videos » LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21 LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21 View the video about CALiPER Report Series 21 on LED Linear Lamps and Troffer Lighting, featuring interviews with Tracy Beeson and Naomi Miller of Pacific Northwest National Laboratory. View the text-alternative version. Solid-State Lighting Home About the Solid-State Lighting Program Research & Development SSL Basics Using LEDs

  1. Linear Dichroism in Resonant Inelastic X-Ray Scattering to Molecular

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Spin-Orbit States Linear Dichroism in Resonant Inelastic X-Ray Scattering to Molecular Spin-Orbit States Linear Dichroism in Resonant Inelastic X-Ray Scattering to Molecular Spin-Orbit States Print Thursday, 17 December 2009 13:47 Schematic representation of linear dichroism observed in KL x-ray emission. Coupling between the spin-orbit interaction and the molecular field, oriented along the chemical bond, leads to different spin-orbit ratios as a function of the angle between the incoming

  2. 13th International Conference on Magnetically Levitated Systems and Linear Drives

    SciTech Connect (OSTI)

    Not Available

    1993-09-01

    This report contains short papers on research being conducted throughout the world on magnetically levitated systems, mainly consisting of trains, and magnetic linear drives. These papers have been index separately elsewhere on the data base.

  3. A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory...

    Office of Scientific and Technical Information (OSTI)

    A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to Multi-TeV Summarized for CSS2013 E. Adli, J.P.Delahaye, S.J.Gessner, M.J. Hogan, T. Raubenheimer (SLAC) W.An,...

  4. The Effective Combination of Mesh Adaptation and Non-linearThermo...

    Office of Scientific and Technical Information (OSTI)

    The Effective Combination of Mesh Adaptation and Non-linear Thermo-mechanical Solution Components for the Modeling of Weld Failures. Citation Details In-Document Search Title: The...

  5. Near equilibrium distributions for beams with space charge in linear and

    Office of Scientific and Technical Information (OSTI)

    nonlinear periodic focusing systems (Journal Article) | SciTech Connect Near equilibrium distributions for beams with space charge in linear and nonlinear periodic focusing systems Citation Details In-Document Search This content will become publicly available on April 29, 2016 Title: Near equilibrium distributions for beams with space charge in linear and nonlinear periodic focusing systems Authors: Sonnad, Kiran G. [1] ; Cary, John R. [1] + Show Author Affiliations Center for Integrated

  6. Measuring anomalous couplings in H→WW* decays at the International Linear

    Office of Scientific and Technical Information (OSTI)

    Collider (Journal Article) | SciTech Connect Measuring anomalous couplings in H→WW* decays at the International Linear Collider Citation Details In-Document Search Title: Measuring anomalous couplings in H→WW* decays at the International Linear Collider Authors: Takubo, Yosuke ; Hodgkinson, Robert N. ; Ikematsu, Katsumasa ; Fujii, Keisuke ; Okada, Nobuchika ; Yamamoto, Hitoshi Publication Date: 2013-07-18 OSTI Identifier: 1103733 Type: Publisher's Accepted Manuscript Journal Name:

  7. Renormalized linear kinetic theory as derived from quantum field theory: A

    Office of Scientific and Technical Information (OSTI)

    novel diagrammatic method for computing transport coefficients (Journal Article) | SciTech Connect Renormalized linear kinetic theory as derived from quantum field theory: A novel diagrammatic method for computing transport coefficients Citation Details In-Document Search Title: Renormalized linear kinetic theory as derived from quantum field theory: A novel diagrammatic method for computing transport coefficients We propose a novel diagrammatic method for computing transport coefficients in

  8. A Linear Theory of Microwave Instability in Electron Storage Rings (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Journal Article: A Linear Theory of Microwave Instability in Electron Storage Rings Citation Details In-Document Search Title: A Linear Theory of Microwave Instability in Electron Storage Rings The well-known Haissinski distribution provides a stable equilibrium of longitudinal beam distribution in electron storage rings below a threshold current. Yet, how to accurately determine this threshold, above which the Haissinski distribution becomes unstable, is not

  9. Vibration Stabilization of a Mechanical Model of a X-Band Linear Collider Final Focus Magnet

    SciTech Connect (OSTI)

    Frisch, Josef; Chang, Allison; Decker, Valentin; Doyle, Eric; Eriksson, Leif; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas; Partridge, Richard; Seryi, Andrei; /SLAC

    2006-09-28

    The small beam sizes at the interaction point of a X-band linear collider require mechanical stabilization of the final focus magnets at the nanometer level. While passive systems provide adequate performance at many potential sites, active mechanical stabilization is useful if the natural or cultural ground vibration is higher than expected. A mechanical model of a room temperature linear collider final focus magnet has been constructed and actively stabilized with an accelerometer based system.

  10. Probing the Linear Polarization of Gluons in Unpolarized Hadrons at EIC

    SciTech Connect (OSTI)

    Boer, Daniel; /Groningen, KVI; Brodsky, Stanley J.; /SLAC; Mulders, Piet J.; /Vrije U., Amsterdam; Pisano, Cristian; /Cagliari U. /INFN, Cagliari

    2011-08-17

    Gluons inside unpolarized hadrons can be linearly polarized provided they have a nonzero transverse momentum. The simplest and theoretically safest way to probe this TMD distribution of linearly polarized gluons is through cos 2{phi} asymmetries in heavy quark pair or dijet production in electron-hadron collisions. Future EIC or LHeC experiments are ideally suited for this purpose. Here we estimate the maximum asymmetries for EIC kinematics.

  11. DYNAMICAL STABILITY AND QUANTUM CHAOS OF IONS IN A LINEAR TRAP (1999002ER).

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (Technical Report) | SciTech Connect Technical Report: DYNAMICAL STABILITY AND QUANTUM CHAOS OF IONS IN A LINEAR TRAP (1999002ER). Citation Details In-Document Search Title: DYNAMICAL STABILITY AND QUANTUM CHAOS OF IONS IN A LINEAR TRAP (1999002ER). The realization of a paradigm chaotic system, namely the harmonically driven oscillator, in the quantum domain using cold trapped ions driven by lasers is theoretically investigated. The simplest characteristics of regular and chaotic dynamics

  12. DOE - Office of Legacy Management -- Yale Heavy Ion Linear Accelerator - CT

    Office of Legacy Management (LM)

    05 Yale Heavy Ion Linear Accelerator - CT 05 FUSRAP Considered Sites Site: Yale Heavy Ion Linear Accelerator (CT.05) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: New Haven , Connecticut CT.05-1 Evaluation Year: 1987 CT.05-3 Site Operations: Research and development with solvents. CT.05-1 Site Disposition: Eliminated - Potential for contamination remote based on limited amount of materials handled CT.05-3 Radioactive Materials

  13. Simple Limits on Achieving A Quasi-Linear Magnetic Compression for an FEL Driver

    SciTech Connect (OSTI)

    Sun, Yipeng; /SLAC

    2012-02-16

    Free electron lasers (FEL) need a very bright electron beam in three dimensions and a high peak charge density. In order to compress an initially longer electron bunch generated from the photoinjector, magnetic bunch compression systems are widely employed. In this paper, first harmonic RF linearization and its associated requirements are reviewed. Meanwhile it is also briefly discussed what is the relation between a proper initial bunch length and main RF frequency, when a harmonic RF linearization is included. Then given a reasonable bunch compression ratio, a proper initial bunch length as a function of the main RF frequency and RF phase is estimated analytically by several approaches, assuming that no harmonic RF section is needed to linearize the energy modulation introduced during main RF acceleration, and at the same time still linearly compress the bunch length. Next the upper limit of the bunch compression ratio in a single stage is evaluated analytically. The analytical relations derived on choosing a proper initial bunch length as a function of main RF frequency are confirmed by numerical simulation. These simple limit provide rough estimations and may be beneficial for choosing bunch compression ratios in different stages of an FEL driver, especially in a first stage bunch compression where there is usually a harmonic RF linearization applied. It may also be useful in evaluating the possibility of low charge operation mode without any harmonic RF linearization, where a shorter initial bunch length can be achieved from the photoinjector.

  14. Amesos2 and Belos: Direct and Iterative Solvers for Large Sparse Linear Systems

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bavier, Eric; Hoemmen, Mark; Rajamanickam, Sivasankaran; Thornquist, Heidi

    2012-01-01

    Solvers for large sparse linear systems come in two categories: direct and iterative. Amesos2, a package in the Trilinos software project, provides direct methods, and Belos, another Trilinos package, provides iterative methods. Amesos2 offers a common interface to many different sparse matrix factorization codes, and can handle any implementation of sparse matrices and vectors, via an easy-to-extend C++ traits interface. It can also factor matrices whose entries have arbitrary “Scalar” type, enabling extended-precision and mixed-precision algorithms. Belos includes many different iterative methods for solving large sparse linear systems and least-squares problems. Unlike competing iterative solver libraries, Belos completely decouples themore » algorithms from the implementations of the underlying linear algebra objects. This lets Belos exploit the latest hardware without changes to the code. Belos favors algorithms that solve higher-level problems, such as multiple simultaneous linear systems and sequences of related linear systems, faster than standard algorithms. The package also supports extended-precision and mixed-precision algorithms. Together, Amesos2 and Belos form a complete suite of sparse linear solvers.« less

  15. Commercial Development of an Advanced, High-Temperature, Linear-Fresnel Based Concentrating Solar Power Concept

    SciTech Connect (OSTI)

    Viljoen, Nolan; Schuknecht, Nathan

    2012-05-28

    Included herein is SkyFuels detailed assessment of the potential for a direct molten salt linear Fresnel collector. Linear Fresnel architecture is of interest because it has features that are well suited for use with molten salt as a heat transfer fluid: the receiver is fixed (only the mirrors track), the receiver diameter is large (reducing risk of freeze events), and the total linear feet of receiver can be reduced due to the large aperture area. Using molten salt as a heat transfer fluid increases the allowable operating temperature of a collector field, and the cost of thermal storage is reduced in proportion to that increase in temperature. At the conclusion of this project, SkyFuel determined that the cost goals set forth in the contract could not be reasonably met. The performance of a Linear Fresnel collector is significantly less than that of a parabolic trough, in particular due to linear Fresnels large optical cosine losses. On an annual basis, the performance is 20 to 30% below that of a parabolic trough per unit area. The linear Fresnel collector and balance of system costs resulted in an LCOE of approximately 9.9/kWhre. Recent work by SkyFuel has resulted in a large aperture trough design (DSP Trough) with an LCOE value of 8.9 /kWhre calculated with comparative financial terms and balance of plant costs (White 2011). Thus, even though the optimized linear Fresnel collector of our design has a lower unit cost than our optimized trough, it cannot overcome the reduction in annual performance.

  16. Spherically symmetric analysis on open FLRW solution in non-linear massive gravity

    SciTech Connect (OSTI)

    Chiang, Chien-I; Izumi, Keisuke; Chen, Pisin E-mail: izumi@phys.ntu.edu.tw

    2012-12-01

    We study non-linear massive gravity in the spherically symmetric context. Our main motivation is to investigate the effect of helicity-0 mode which remains elusive after analysis of cosmological perturbation around an open Friedmann-Lemaitre-Robertson-Walker (FLRW) universe. The non-linear form of the effective energy-momentum tensor stemming from the mass term is derived for the spherically symmetric case. Only in the special case where the area of the two sphere is not deviated away from the FLRW universe, the effective energy momentum tensor becomes completely the same as that of cosmological constant. This opens a window for discriminating the non-linear massive gravity from general relativity (GR). Indeed, by further solving these spherically symmetric gravitational equations of motion in vacuum to the linear order, we obtain a solution which has an arbitrary time-dependent parameter. In GR, this parameter is a constant and corresponds to the mass of a star. Our result means that Birkhoff's theorem no longer holds in the non-linear massive gravity and suggests that energy can probably be emitted superluminously (with infinite speed) on the self-accelerating background by the helicity-0 mode, which could be a potential plague of this theory.

  17. NON-BAROTROPIC LINEAR ROSSBY WAVE INSTABILITY IN THREE-DIMENSIONAL DISKS

    SciTech Connect (OSTI)

    Lin, Min-Kai

    2013-03-10

    Astrophysical disks with localized radial structure, such as protoplanetary disks containing dead zones or gaps due to disk-planet interaction, may be subject to the non-axisymmetric Rossby wave instability (RWI) that leads to vortex formation. The linear instability has recently been demonstrated in three-dimensional (3D) barotropic disks. It is the purpose of this study to generalize the 3D linear problem to include an energy equation, thereby accounting for baroclinity in three dimensions. Linear stability calculations are presented for radially structured, vertically stratified, geometrically thin disks with non-uniform entropy distribution in both directions. Polytropic equilibria are considered but adiabatic perturbations assumed. The unperturbed disk has a localized radial density bump, making it susceptible to the RWI. The linearized fluid equations are solved numerically as a partial differential equation eigenvalue problem. Emphasis on the ease of method implementation is given. It is found that when the polytropic index is fixed and adiabatic index increased, non-uniform entropy has negligible effect on the RWI growth rate, but pressure and density perturbation magnitudes near a pressure enhancement increase away from the midplane. The associated meridional flow is also qualitatively changed from homentropic calculations. Meridional vortical motion is identified in the nonhomentropic linear solution, as well as in a nonlinear global hydrodynamic simulation of the RWI in an initially isothermal disk evolved adiabatically. Numerical results suggest that buoyancy forces play an important role in the internal flow of Rossby vortices.

  18. Tunnel magnetoresistance and linear conductance of double quantum dots strongly coupled to ferromagnetic leads

    SciTech Connect (OSTI)

    Weymann, Ireneusz

    2015-05-07

    We analyze the spin-dependent linear-response transport properties of double quantum dots strongly coupled to external ferromagnetic leads. By using the numerical renormalization group method, we determine the dependence of the linear conductance and tunnel magnetoresistance on the degree of spin polarization of the leads and the position of the double dot levels. We focus on the transport regime where the system exhibits the SU(4) Kondo effect. It is shown that the presence of ferromagnets generally leads the suppression of the linear conductance due to the presence of an exchange field. Moreover, the exchange field gives rise to a transition from the SU(4) to the orbital SU(2) Kondo effect. We also analyze the dependence of the tunnel magnetoresistance on the double dot levels' positions and show that it exhibits a very nontrivial behavior.

  19. Non-Linear Transmission Line (NLTL) Microwave Source Lecture Notes the United States Particle Accelerator School

    SciTech Connect (OSTI)

    Russell, Steven J.; Carlsten, Bruce E.

    2012-06-26

    We will quickly go through the history of the non-linear transmission lines (NLTLs). We will describe how they work, how they are modeled and how they are designed. Note that the field of high power, NLTL microwave sources is still under development, so this is just a snap shot of their current state. Topics discussed are: (1) Introduction to solitons and the KdV equation; (2) The lumped element non-linear transmission line; (3) Solution of the KdV equation; (4) Non-linear transmission lines at microwave frequencies; (5) Numerical methods for NLTL analysis; (6) Unipolar versus bipolar input; (7) High power NLTL pioneers; (8) Resistive versus reactive load; (9) Non-lineaer dielectrics; and (10) Effect of losses.

  20. Nonlinear and linear timescales near kinetic scales in solar wind turbulence

    SciTech Connect (OSTI)

    Matthaeus, W. H.; Wan, M.; Shay, M. A.; Oughton, S.; Osman, K. T.; Chapman, S. C.; Servidio, S.; Valentini, F.; Gary, S. P.; Roytershteyn, V.; Karimabadi, H.

    2014-08-01

    The application of linear kinetic treatments to plasma waves, damping, and instability requires favorable inequalities between the associated linear timescales and timescales for nonlinear (e.g., turbulence) evolution. In the solar wind these two types of timescales may be directly compared using standard Kolmogorov-style analysis and observational data. The estimated local (in scale) nonlinear magnetohydrodynamic cascade times, evaluated as relevant kinetic scales are approached, remain slower than the cyclotron period, but comparable to or faster than the typical timescales of instabilities, anisotropic waves, and wave damping. The variation with length scale of the turbulence timescales is supported by observations and simulations. On this basis the use of linear theorywhich assumes constant parameters to calculate the associated kinetic ratesmay be questioned. It is suggested that the product of proton gyrofrequency and nonlinear time at the ion gyroscales provides a simple measure of turbulence influence on proton kinetic behavior.

  1. Large linear magnetoresistance in a GaAs/AlGaAs heterostructure

    SciTech Connect (OSTI)

    Aamir, Mohammed Ali, E-mail: aamir@physics.iisc.ernet.in; Goswami, Srijit, E-mail: aamir@physics.iisc.ernet.in; Ghosh, Arindam [Department of Physics, Indian Institute of Science, Bangalore 560 012 (India); Baenninger, Matthias; Farrer, Ian; Ritchie, David A. [Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Tripathi, Vikram [Department of Theoretical Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Pepper, Michael [Department of Electrical and Electronic Engineering, University College, London WC1E 7JE (United Kingdom)

    2013-12-04

    We report non-saturating linear magnetoresistance (MR) in a two-dimensional electron system (2DES) at a GaAs/AlGaAs heterointerface in the strongly insulating regime. We achieve this by driving the gate voltage below the pinch-off point of the device and operating it in the non-equilibrium regime with high source-drain bias. Remarkably, the magnitude of MR is as large as 500% per Tesla with respect to resistance at zero magnetic field, thus dwarfing most non-magnetic materials which exhibit this linearity. Its primary advantage over most other materials is that both linearity and the enormous magnitude are retained over a broad temperature range (0.3 K to 10 K), thus making it an attractive candidate for cryogenic sensor applications.

  2. Exact transition probabilities for a linear sweep through a Kramers-Kronig

    Office of Scientific and Technical Information (OSTI)

    resonance (Journal Article) | SciTech Connect for a linear sweep through a Kramers-Kronig resonance Citation Details In-Document Search This content will become publicly available on November 19, 2016 Title: Exact transition probabilities for a linear sweep through a Kramers-Kronig resonance Authors: Sun, Chen ; Sinitsyn, N. A. Publication Date: 2015-11-20 OSTI Identifier: 1239010 Grant/Contract Number: AC52-06NA25396 Type: Publisher's Accepted Manuscript Journal Name: Journal of Physics A:

  3. DYNAMICAL STABILITY AND QUANTUM CHAOS OF IONS IN A LINEAR TRAP (1999002ER).

    Office of Scientific and Technical Information (OSTI)

    (Technical Report) | SciTech Connect Technical Report: DYNAMICAL STABILITY AND QUANTUM CHAOS OF IONS IN A LINEAR TRAP (1999002ER). Citation Details In-Document Search Title: DYNAMICAL STABILITY AND QUANTUM CHAOS OF IONS IN A LINEAR TRAP (1999002ER). × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional

  4. A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to

    Office of Scientific and Technical Information (OSTI)

    Multi-TeV (Conference) | SciTech Connect Conference: A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to Multi-TeV Citation Details In-Document Search Title: A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to Multi-TeV Authors: Adli, E ; Delahaye, J.P. ; Gessner, S.J. ; Hogan, M.J. ; Raubenheimer, T. ; /SLAC ; An, W. ; Joshi, C. ; Mori, W. ; /UCLA, Los Angeles Publication Date: 2013-09-30 OSTI Identifier: 1074154 Report Number(s): SLAC-PUB-15426 DOE

  5. Sixth-Order Resonance of High-Intensity Linear Accelerators (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Sixth-Order Resonance of High-Intensity Linear Accelerators Citation Details In-Document Search This content will become publicly available on May 5, 2016 Title: Sixth-Order Resonance of High-Intensity Linear Accelerators Authors: Jeon, Dong-O ; Hwang, Kyung Ryun ; Jang, Ji-Ho ; Jin, Hyunchang ; Jang, Hyojae Publication Date: 2015-05-06 OSTI Identifier: 1179719 Grant/Contract Number: FG02-12ER41800 Type: Publisher's Accepted Manuscript Journal Name: Physical Review

  6. Spin relaxation and linear-in-electric-field frequency shift in an

    Office of Scientific and Technical Information (OSTI)

    arbitrary, time-independent magnetic field (Technical Report) | SciTech Connect Technical Report: Spin relaxation and linear-in-electric-field frequency shift in an arbitrary, time-independent magnetic field Citation Details In-Document Search Title: Spin relaxation and linear-in-electric-field frequency shift in an arbitrary, time-independent magnetic field A method is presented to calculate the spin relaxation times T{sub 1}, T{sub 2} due to a nonuniform magnetic field, and the

  7. Spin relaxation and linear-in-electric-field frequency shift in an

    Office of Scientific and Technical Information (OSTI)

    arbitrary, time-independent magnetic field (Technical Report) | SciTech Connect Technical Report: Spin relaxation and linear-in-electric-field frequency shift in an arbitrary, time-independent magnetic field Citation Details In-Document Search Title: Spin relaxation and linear-in-electric-field frequency shift in an arbitrary, time-independent magnetic field × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of

  8. Linear motion device and method for inserting and withdrawing control rods

    DOE Patents [OSTI]

    Smith, Jay E.

    1984-01-01

    A linear motion device, more specifically a control rod drive mechanism (CRDM) for inserting and withdrawing control rods into a reactor core, is capable of independently and sequentially positioning two sets of control rods with a single motor stator and rotor. The CRDM disclosed can control more than one control rod lead screw without incurring a substantial increase in the size of the mechanism.

  9. DOE Publishes CALiPER Report on Cost-Effectiveness of Linear (T8) LED Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 21.3, which is part of a series of investigations on linear LED lamps. Report 21.3 details a set of life-cycle cost simulations...

  10. The feasibility of using methylene blue sensitized polyvinylalcohol film as a linear polarizer

    SciTech Connect (OSTI)

    Jyothilakshmi, K.; Anju, K. S.; Arathy, K.; John, Beena Mary; Krishna, P. B.; Sruthi, C. T.; Chacko, Maria

    2014-01-28

    Linear light polarizing films selectively transmit radiations vibrating along an electromagnetic radiation vector and selectively absorb radiations vibrating along a second electromagnetic radiation vector. It happens according to the anisotropy of the film . In the present study the polarization effects of methylene blue sensitized polyvinyl alcohol is investigated. The polarization effects on the dye concentration, heating and stretching of film also are evaluated.

  11. Photoelectron linear accelerator for producing a low emittance polarized electron beam

    DOE Patents [OSTI]

    Yu, David U.; Clendenin, James E.; Kirby, Robert E.

    2004-06-01

    A photoelectron linear accelerator for producing a low emittance polarized electric beam. The accelerator includes a tube having an inner wall, the inner tube wall being coated by a getter material. A portable, or demountable, cathode plug is mounted within said tube, the surface of said cathode having a semiconductor material formed thereon.

  12. Higgs Coupling Measurements at a 1 TeV Linear Collider

    SciTech Connect (OSTI)

    Barklow, T

    2003-12-18

    Methods for extracting Higgs boson signals at a 1 TeV center-of-mass energy e{sup +}e{sup -} linear collider are described. In addition, estimates are given for the accuracy with which branching fractions can be measured for Higgs boson decays to b{bar b} WW, gg, and {gamma}{gamma}.

  13. Damping of linear waves via ionization and recombination in homogeneous plasmas

    SciTech Connect (OSTI)

    Dodin, I. Y.; Fisch, N. J.

    2010-11-15

    An oscillation-center model is proposed that analytically describes transformation of an arbitrary homogeneous linear wave at gradual ionization and recombination in homogeneous plasma. For the case when either of the processes dominates, general adiabatic invariants are found, from which the wave energy is derived as a function of the frequency.

  14. High-efficiency acceleration in the laser wakefield by a linearly increasing plasma density

    SciTech Connect (OSTI)

    Dong, Kegong; Wu, Yuchi; Zhu, Bin; Zhang, Zhimeng; Zhao, Zongqing; Zhou, Weimin; Hong, Wei; Cao, Leifeng; Gu, Yuqiu

    2014-12-15

    The acceleration length and the peak energy of the electron beam are limited by the dephasing effect in the laser wakefield acceleration with uniform plasma density. Based on 2D-3V particle in cell simulations, the effects of a linearly increasing plasma density on the electron acceleration are investigated broadly. Comparing with the uniform plasma density, because of the prolongation of the acceleration length and the gradually increasing accelerating field due to the increasing plasma density, the electron beam energy is twice higher in moderate nonlinear wakefield regime. Because of the lower plasma density, the linearly increasing plasma density can also avoid the dark current caused by additional injection. At the optimal acceleration length, the electron energy can be increased from 350 MeV (uniform) to 760 MeV (linearly increasing) with the energy spread of 1.8%, the beam duration is 5 fs and the beam waist is 1.25 μm. This linearly increasing plasma density distribution can be achieved by a capillary with special gas-filled structure, and is much more suitable for experiment.

  15. DOE Publishes CALiPER Report on Linear (T8) LED Lamps in a 2x4 K12-Lensed

    Energy Savers [EERE]

    Troffer | Department of Energy Linear (T8) LED Lamps in a 2x4 K12-Lensed Troffer DOE Publishes CALiPER Report on Linear (T8) LED Lamps in a 2x4 K12-Lensed Troffer May 2, 2014 - 4:48pm Addthis The U.S. Department of Energy's CALiPER program has released Report 21.1, which is part of a series of investigations on linear LED lamps. Report 21.1 focuses on the performance of 31 types of linear LED lamps operated in a typical 2x4 troffer with a K12 prismatic lens. The lamps were intended as

  16. Comparative study of microwave radiation-induced magnetoresistive oscillations induced by circularly- and linearly- polarized photo-excitation

    SciTech Connect (OSTI)

    Ye, Tianyu; Liu, Han -Chun; Wang, Zhuo; Wegscheider, W.; Mani, Ramesh G.

    2015-10-09

    A comparative study of the radiation-induced magnetoresistance oscillations in the high mobility GaAs/AlGaAs heterostructure two dimensional electron system (2DES) under linearly- and circularly- polarized microwave excitation indicates a profound difference in the response observed upon rotating the microwave launcher for the two cases, although circularly polarized microwave radiation induced magnetoresistance oscillations observed at low magnetic fields are similar to the oscillations observed with linearly polarized radiation. For the linearly polarized radiation, the magnetoresistive response is a strong sinusoidal function of the launcher rotation (or linear polarization) angle, θ. As a result, for circularly polarized radiation, the oscillatory magnetoresistive response is hardly sensitive to θ.

  17. Self-consistent field theory based molecular dynamics with linear system-size scaling

    SciTech Connect (OSTI)

    Richters, Dorothee; Khne, Thomas D.

    2014-04-07

    We present an improved field-theoretic approach to the grand-canonical potential suitable for linear scaling molecular dynamics simulations using forces from self-consistent electronic structure calculations. It is based on an exact decomposition of the grand canonical potential for independent fermions and does neither rely on the ability to localize the orbitals nor that the Hamilton operator is well-conditioned. Hence, this scheme enables highly accurate all-electron linear scaling calculations even for metallic systems. The inherent energy drift of Born-Oppenheimer molecular dynamics simulations, arising from an incomplete convergence of the self-consistent field cycle, is circumvented by means of a properly modified Langevin equation. The predictive power of the present approach is illustrated using the example of liquid methane under extreme conditions.

  18. Linear and nonlinear dust acoustic waves in an inhomogeneous magnetized dusty plasma with nonextensive electrons

    SciTech Connect (OSTI)

    El-Taibany, W. F. E-mail: eltaibany@hotmail.com; Selim, M. M.; Al-Abbasy, O. M.; El-Bedwehy, N. A.

    2014-07-15

    The propagation of both linear and nonlinear dust acoustic waves (DAWs) in an inhomogeneous magnetized collisional and warm dusty plasma (DP) consisting of Boltzmann ions, nonextensive electrons, and inertial dust particles is investigated. The number density gradients of all DP components besides the inhomogeneities of electrostatic potential and the initial dust fluid velocity are taken into account. The linear dispersion relation and a nonlinear modified Zakharov-Kusnetsov (MZK) equation governing the propagation of the three-dimensional DAWs are derived. The analytical solution of the MZK reveals the creation of both compressive and rarefactive DAW solitons in the proposed model. It is found that the inhomogeneity dimension parameter and the electron nonextensive parameter affect significantly the nonlinear DAW's amplitude, width, and Mach number. The relations of our findings with some astrophysical situations have been given.

  19. Solar receiver heliostat reflector having a linear drive and position information system

    DOE Patents [OSTI]

    Horton, Richard H. (Schenectady, NY)

    1980-01-01

    A heliostat for a solar receiver system comprises an improved drive and control system for the heliostat reflector assembly. The heliostat reflector assembly is controllably driven in a predetermined way by a light-weight drive system so as to be angularly adjustable in both elevation and azimuth to track the sun and efficiently continuously reflect the sun's rays to a focal zone, i.e., heat receiver, which forms part of a solar energy utilization system, such as a solar energy fueled electrical power generation system. The improved drive system includes linear stepping motors which comprise low weight, low cost, electronic pulse driven components. One embodiment comprises linear stepping motors controlled by a programmed, electronic microprocessor. Another embodiment comprises a tape driven system controlled by a position control magnetic tape.

  20. Estimation of Heavy Ion Densities From Linearly Polarized EMIC Waves At Earth

    SciTech Connect (OSTI)

    Kim, Eun-Hwa; Johnson, Jay R.; Lee, Dong-Hun

    2014-02-24

    Linearly polarized EMIC waves are expected to concentrate at the location where their wave frequency satisfies the ion-ion hybrid (IIH) resonance condition as the result of a mode conversion process. In this letter, we evaluate absorption coefficients at the IIH resonance in the Earth geosynchronous orbit for variable concentrations of helium and azimuthal and field-aligned wave numbers in dipole magnetic field. Although wave absorption occurs for a wide range of heavy ion concentration, it only occurs for a limited range of azimuthal and field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. Our results suggest that, at L = 6.6, linearly polarized EMIC waves can be generated via mode conversion from the compressional waves near the crossover frequency. Consequently, the heavy ion concentration ratio can be estimated from observations of externally generated EMIC waves that have polarization.

  1. Explicit expressions for three-dimensional boundary integrals in linear elasticity

    SciTech Connect (OSTI)

    Nintcheu Fata, Sylvain

    2011-01-01

    On employing isoparametric, piecewise linear shape functions over a flat triangle, exact formulae are derived for all surface potentials involved in the numerical treatment of three-dimensional singular and hyper-singular boundary integral equations in linear elasticity. These formulae are valid for an arbitrary source point in space and are represented as analytical expressions along the edges of the integration triangle. They can be employed to solve integral equations defined on triangulated surfaces via a collocation method or may be utilized as analytical expressions for the inner integrals in a Galerkin technique. A numerical example involving a unit triangle and a source point located at various distances above it, as well as sample problems solved by a collocation boundary element method for the Lame equation are included to validate the proposed formulae.

  2. Variational principle for linear stability of flowing plasmas in Hall magnetohydrodynamics

    SciTech Connect (OSTI)

    Hirota, M.; Yoshida, Z.; Hameiri, E.

    2006-02-15

    Linear stability of equilibrium states with flow is studied by means of the variational principle in Hall magnetohydrodynamics (MHD). The Lagrangian representation of the linearized Hall MHD equation is performed by considering special perturbations that preserves some constants of motion (the Casimir invariants). The resultant equation has a Hamiltonian structure which enables the variational principle. There is however some difficulties in showing the positive definiteness of the quadratic form in the presence of flow. The dynamically accessible variation is a more restricted class of perturbations which, by definition, preserves all the Casimir invariants. For such variations, the quadratic form (the second variation of Hamiltonian) can be positive definite. Some conditions for stability are derived by applying this variational principle to the double Beltrami equilibrium.

  3. Reliable clock estimation using linear weighted fusion based on pairwise broadcast synchronization

    SciTech Connect (OSTI)

    Shi, Xin Zhao, Xiangmo Hui, Fei Ma, Junyan Yang, Lan

    2014-10-06

    Clock synchronization in wireless sensor networks (WSNs) has been studied extensively in recent years and many protocols are put forward based on the point of statistical signal processing, which is an effective way to optimize accuracy. However, the accuracy derived from the statistical data can be improved mainly by sufficient packets exchange, which will consume the limited power resources greatly. In this paper, a reliable clock estimation using linear weighted fusion based on pairwise broadcast synchronization is proposed to optimize sync accuracy without expending additional sync packets. As a contribution, a linear weighted fusion scheme for multiple clock deviations is constructed with the collaborative sensing of clock timestamp. And the fusion weight is defined by the covariance of sync errors for different clock deviations. Extensive simulation results show that the proposed approach can achieve better performance in terms of sync overhead and sync accuracy.

  4. Linear magnetoresistance caused by mobility fluctuations in n-doped Cd3As2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Narayanan, A.; Watson, M. D.; Blake, S. F.; Bruyant, N.; Drigo, L.; Chen, Y. L.; Prabhakaran, D.; Yan, B.; Felser, C.; Kong, T.; et al

    2015-03-19

    Cd3As2 is a candidate three-dimensional Dirac semimetal which has exceedingly high mobility and nonsaturating linear magnetoresistance that may be relevant for future practical applications. We report magnetotransport and tunnel diode oscillation measurements on Cd3As2, in magnetic fields up to 65 T and temperatures between 1.5 and 300 K. We find that the nonsaturating linear magnetoresistance persists up to 65 T and it is likely caused by disorder effects, as it scales with the high mobility rather than directly linked to Fermi surface changes even when approaching the quantum limit. As a result of the observed quantum oscillations, we determine themore » bulk three-dimensional Fermi surface having signatures of Dirac behavior with a nontrivial Berry phase shift, very light effective quasiparticle masses, and clear deviations from the band-structure predictions. In very high fields we also detect signatures of large Zeeman spin splitting (g~16).« less

  5. Stanford Linear Accelerator Center, Order R2-2005-0022, May 18, 2005

    Office of Environmental Management (EM)

    CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD SAN FRANCISCO BAY REGION ORDER No. R2-2005-0022 RESCISSION of: ORDER No. 85-88, WASTE DISCHARGE REQUIREMENTS and ADOPTION of: SITE CLEANUP REQUIREMENTS for: STANFORD UNIVERSITY and the UNITED STATES DEPARTMENT OF ENERGY for the property located at the: STANFORD LINEAR ACCELERATOR CENTER 2575 SAND HILL ROAD MENLO PARK, SAN MATEO COUNTY FINDINGS: The California Regional Water Quality Control Board, San Francisco Bay Region (Water Board) finds that:

  6. Orbit correction in a linear nonscaling fixed field alternating gradient accelerator

    SciTech Connect (OSTI)

    Kelliher, D. J.; Machida, S.; Edmonds, C. S.; Kirkman, I. W.; Jones, J. K.; Muratori, B. D.; Garland, J. M.; Berg, J. S.

    2014-11-01

    In a linear non-scaling FFAG the large natural chromaticity of the machine results in a betatron tune that varies by several integers over the momentum range. Orbit correction is complicated by the consequent variation of the phase advance between lattice elements. Here we investigate how the correction of multiple closed orbit harmonics allows correction of both the COD and the accelerated orbit distortion over the momentum range.

  7. Linear motion device and method for inserting and withdrawing control rods

    DOE Patents [OSTI]

    Smith, J.E.

    Disclosed is a linear motion device and more specifically a control rod drive mechanism (CRDM) for inserting and withdrawing control rods into a reactor core. The CRDM and method disclosed is capable of independently and sequentially positioning two sets of control rods with a single motor stator and rotor. The CRDM disclosed can control more than one control rod lead screw without incurring a substantial increase in the size of the mechanism.

  8. Evolution of the design of a silicon tracker for the Linear Collider

    SciTech Connect (OSTI)

    Cooper, W.E.

    2005-10-01

    A design for the silicon tracker for SiD was proposed at the Victoria Linear Collider Workshop [1]. This paper describes development of that design by the SiD group into a baseline model for simulation studies. The design has been modified to take into account detector fabrication and servicing requirements, features specific to the vertex chamber, and detector elements in the region surrounding the silicon tracker.

  9. DOE Publishes CALiPER Report on Cost-Effectiveness of Linear (T8) LED Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 21.3, which is part of a series of investigations on linear LED lamps. Report 21.3 details a set of life-cycle cost simulations that compared a two-lamp troffer using LED lamps (38W total power draw) or fluorescent lamps (51W total power draw) over a 10-year study period.

  10. Towards time-dependent current-density-functional theory in the non-linear regime

    SciTech Connect (OSTI)

    Escartn, J. M.; Vincendon, M.; Dinh, P. M.; Suraud, E.; Romaniello, P.; Reinhard, P.-G.

    2015-02-28

    Time-Dependent Density-Functional Theory (TDDFT) is a well-established theoretical approach to describe and understand irradiation processes in clusters and molecules. However, within the so-called adiabatic local density approximation (ALDA) to the exchange-correlation (xc) potential, TDDFT can show insufficiencies, particularly in violently dynamical processes. This is because within ALDA the xc potential is instantaneous and is a local functional of the density, which means that this approximation neglects memory effects and long-range effects. A way to go beyond ALDA is to use Time-Dependent Current-Density-Functional Theory (TDCDFT), in which the basic quantity is the current density rather than the density as in TDDFT. This has been shown to offer an adequate account of dissipation in the linear domain when the Vignale-Kohn (VK) functional is used. Here, we go beyond the linear regime and we explore this formulation in the time domain. In this case, the equations become very involved making the computation out of reach; we hence propose an approximation to the VK functional which allows us to calculate the dynamics in real time and at the same time to keep most of the physics described by the VK functional. We apply this formulation to the calculation of the time-dependent dipole moment of Ca, Mg and Na{sub 2}. Our results show trends similar to what was previously observed in model systems or within linear response. In the non-linear domain, our results show that relaxation times do not decrease with increasing deposited excitation energy, which sets some limitations to the practical use of TDCDFT in such a domain of excitations.

  11. Quasi-linear heating and acceleration in bi-Maxwellian plasmas

    SciTech Connect (OSTI)

    Hellinger, Petr; Trvn?ek, Pavel M.

    2013-12-15

    Quasi-linear acceleration and heating rates are derived for drifting bi-Maxwellian distribution functions in a general nonrelativistic case for arbitrary wave vectors, propagation angles, and growth/damping rates. The heating rates in a proton-electron plasma due to ion-cyclotron/kinetic Alfvn and mirror waves for a wide range of wavelengths, directions of propagation, and growth or damping rates are explicitly computed.

  12. A modified post damping ring bunch compressor beamline for the TESLA linear collider

    SciTech Connect (OSTI)

    Philippe R.-G. Piot; Winfried Decking

    2004-03-23

    We propose a modified bunch compressor beamline, downstream of the damping ring, for the TESLA linear collider. This modified beamline uses a third harmonic radio-frequency section based on the 3.9 GHz superconducting cavity under development at Fermilab. In our design the beam deceleration is about {approx}50 MeV instead of {approx}450 MeV in the original design proposed.

  13. Final Report for the UNIVERSITY-BASED DETECTOR RESEARCH AND DEVELOPMENT FOR THE INTERNATIONAL LINEAR COLLIDER

    SciTech Connect (OSTI)

    Brau, James E

    2013-04-22

    The U.S Linear Collider Detector R&D program, supported by the DOE and NSF umbrella grants to the University of Oregon, made significant advances on many critical aspects of the ILC detector program. Progress advanced on vertex detector sensor development, silicon and TPC tracking, calorimetry on candidate technologies, and muon detection, as well as on beamline measurements of luminosity, energy, and polarization.

  14. Orbit correction in a linear nonscaling fixed field alternating gradient accelerator

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kelliher, D. J.; Machida, S.; Edmonds, C. S.; Kirkman, I. W.; Jones, J. K.; Muratori, B. D.; Garland, J. M.; Berg, J. S.

    2014-11-20

    In a linear non-scaling FFAG the large natural chromaticity of the machine results in a betatron tune that varies by several integers over the momentum range. In addition, orbit correction is complicated by the consequent variation of the phase advance between lattice elements. Here we investigate how the correction of multiple closed orbit harmonics allows correction of both the COD and the accelerated orbit distortion over the momentum range.

  15. A Novel MagPipe Pipeline transportation system using linear motor drives

    SciTech Connect (OSTI)

    Fang, J.R.; Montgomery, D.B.; Roderick, L.

    2009-11-15

    A novel capsule pipeline transportation system using linear motor drives, called Magplane MagPipe, is under development with the intention to replace trucks and railways for hauling materials from the mine to the rail head, power plant, or processing plant with reduced operating cost and energy consumption. The initial demonstration of a MagPipe line in Inner Mongolia will be a 500-m-long double-pipe coal transport system with the design transportation capacity of 3 Mega-Mg per year. The pipeline consists of 6-m-long plastic pipe modules with an I-beam suspension system inside the pipe to carry sets of five coupled capsules. The pipe will also contain noncontinuous motor winding modules spaced at 50-m intervals. A set of Halbach-arrayed permanent magnets on the bottom of the capsules interact with the linear motor windings to provide propulsion. The motor is driven by variable frequency drives outside the pipe to control the speed. This paper briefly describes the overall MagPipe pipeline transportation system, including the preliminary conclusions of the linear synchronous motor analysis.

  16. Effective Yukawa couplings and flavor-changing Higgs boson decays at linear colliders

    SciTech Connect (OSTI)

    Gabrielli, E.; Mele, B.

    2011-04-01

    We analyze the advantages of a linear-collider program for testing a recent theoretical proposal where the Higgs boson Yukawa couplings are radiatively generated, keeping unchanged the standard-model mechanism for electroweak-gauge-symmetry breaking. Fermion masses arise at a large energy scale through an unknown mechanism, and the standard model at the electroweak scale is regarded as an effective field theory. In this scenario, Higgs boson decays into photons and electroweak gauge-boson pairs are considerably enhanced for a light Higgs boson, which makes a signal observation at the LHC straightforward. On the other hand, the clean environment of a linear collider is required to directly probe the radiative fermionic sector of the Higgs boson couplings. Also, we show that the flavor-changing Higgs boson decays are dramatically enhanced with respect to the standard model. In particular, we find a measurable branching ratio in the range (10{sup -4}-10{sup -3}) for the decay H{yields}bs for a Higgs boson lighter than 140 GeV, depending on the high-energy scale where Yukawa couplings vanish. We present a detailed analysis of the Higgs boson production cross sections at linear colliders for interesting decay signatures, as well as branching-ratio correlations for different flavor-conserving/nonconserving fermionic decays.

  17. Subsurface failure in spherical bodies. A formation scenario for linear troughs on Vestas surface

    SciTech Connect (OSTI)

    Stickle, Angela M.; Schultz, P. H.; Crawford, D. A.

    2014-10-13

    Many asteroids in the Solar System exhibit unusual, linear features on their surface. The Dawn mission recently observed two sets of linear features on the surface of the asteroid 4 Vesta. Geologic observations indicate that these features are related to the two large impact basins at the south pole of Vesta, though no specific mechanism of origin has been determined. Furthermore, the orientation of the features is offset from the center of the basins. Experimental and numerical results reveal that the offset angle is a natural consequence of oblique impacts into a spherical target. We demonstrate that a set of shear planes develops in the subsurface of the body opposite to the point of first contact. Moreover, these subsurface failure zones then propagate to the surface under combined tensile-shear stress fields after the impact to create sets of approximately linear faults on the surface. Comparison between the orientation of damage structures in the laboratory and failure regions within Vesta can be used to constrain impact parameters (e.g., the approximate impact point and likely impact trajectory).

  18. CALiPER Report 21.3: Cost-Effectiveness of Linear (T8) LED Lamps

    SciTech Connect (OSTI)

    Miller, Naomi J.; Perrin, Tess E.; Royer, Michael P.

    2014-05-27

    Meeting performance expectations is important for driving adoption of linear LED lamps, but cost-effectiveness may be an overriding factor in many cases. Linear LED lamps cost more initially than fluorescent lamps, but energy and maintenance savings may mean that the life-cycle cost is lower. This report details a series of life-cycle cost simulations that compared a two-lamp troffer using LED lamps (38 W total power draw) or fluorescent lamps (51 W total power draw) over a 10-year study period. Variables included LED system cost ($40, $80, or $120), annual operating hours (2,000 hours or 4,000 hours), LED installation time (15 minutes or 30 minutes), and melded electricity rate ($0.06/kWh, $0.12/kWh, $0.18/kWh, or $0.24/kWh). A full factorial of simulations allows users to interpolate between these values to aid in making rough estimates of economic feasibility for their own projects. In general, while their initial cost premium remains high, linear LED lamps are more likely to be cost-effective when electric utility rates are higher than average and hours of operation are long, and if their installation time is shorter.

  19. CALiPER Report 21.3. Cost Effectiveness of Linear (T8) LED Lamps

    SciTech Connect (OSTI)

    2014-05-01

    Meeting performance expectations is important for driving adoption of linear LED lamps, but cost-effectiveness may be an overriding factor in many cases. Linear LED lamps cost more initially than fluorescent lamps, but energy and maintenance savings may mean that the life-cycle cost is lower. This report details a series of life-cycle cost simulations that compared a two-lamp troffer using LED lamps (38 W total power draw) or fluorescent lamps (51 W total power draw) over a 10-year study period. Variables included LED system cost ($40, $80, or $120), annual operating hours (2,000 hours or 4,000 hours), LED installation time (15 minutes or 30 minutes), and melded electricity rate ($0.06/kWh, $0.12/kWh, $0.18/kWh, or $0.24/kWh). A full factorial of simulations allows users to interpolate between these values to aid in making rough estimates of economic feasibility for their own projects. In general, while their initial cost premium remains high, linear LED lamps are more likely to be cost-effective when electric utility rates are higher than average and hours of operation are long, and if their installation time is shorter.

  20. Subsurface failure in spherical bodies. A formation scenario for linear troughs on Vesta’s surface

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Stickle, Angela M.; Schultz, P. H.; Crawford, D. A.

    2014-10-13

    Many asteroids in the Solar System exhibit unusual, linear features on their surface. The Dawn mission recently observed two sets of linear features on the surface of the asteroid 4 Vesta. Geologic observations indicate that these features are related to the two large impact basins at the south pole of Vesta, though no specific mechanism of origin has been determined. Furthermore, the orientation of the features is offset from the center of the basins. Experimental and numerical results reveal that the offset angle is a natural consequence of oblique impacts into a spherical target. We demonstrate that a set ofmore » shear planes develops in the subsurface of the body opposite to the point of first contact. Moreover, these subsurface failure zones then propagate to the surface under combined tensile-shear stress fields after the impact to create sets of approximately linear faults on the surface. Comparison between the orientation of damage structures in the laboratory and failure regions within Vesta can be used to constrain impact parameters (e.g., the approximate impact point and likely impact trajectory).« less

  1. MULTIPASS MUON RLA RETURN ARCS BASED ON LINEAR COMBINED-FUNCTION MAGNETS

    SciTech Connect (OSTI)

    Vasiliy Morozov, Alex Bogacz, Yves Roblin, Kevin Beard

    2011-09-01

    Recirculating Linear Accelerators (RLA) are an efficient way of accelerating short-lived muons to the multi-GeV energies required for Neutrino Factories and TeV energies required for Muon Colliders. In this paper we present a design of a two-pass RLA return arc based on linear combined function magnets, in which both charge muons with momenta different by a factor of two are transported through the same string of magnets. The arc is composed of 60{sup o}-bending symmetric super cells allowing for a simple arc geometry closing. By adjusting the dipole and quadrupole components of the combined-function magnets, each super cell is designed to be achromatic and to have zero initial and final periodic orbit offsets for both muon momenta. Such a design provides a greater compactness than, for instance, an FFAG lattice with its regular alternating bends and is expected to possess a large dynamic aperture characteristic of linear-field lattices.

  2. Bit error rate tester using fast parallel generation of linear recurring sequences

    DOE Patents [OSTI]

    Pierson, Lyndon G.; Witzke, Edward L.; Maestas, Joseph H.

    2003-05-06

    A fast method for generating linear recurring sequences by parallel linear recurring sequence generators (LRSGs) with a feedback circuit optimized to balance minimum propagation delay against maximal sequence period. Parallel generation of linear recurring sequences requires decimating the sequence (creating small contiguous sections of the sequence in each LRSG). A companion matrix form is selected depending on whether the LFSR is right-shifting or left-shifting. The companion matrix is completed by selecting a primitive irreducible polynomial with 1's most closely grouped in a corner of the companion matrix. A decimation matrix is created by raising the companion matrix to the (n*k).sup.th power, where k is the number of parallel LRSGs and n is the number of bits to be generated at a time by each LRSG. Companion matrices with 1's closely grouped in a corner will yield sparse decimation matrices. A feedback circuit comprised of XOR logic gates implements the decimation matrix in hardware. Sparse decimation matrices can be implemented with minimum number of XOR gates, and therefore a minimum propagation delay through the feedback circuit. The LRSG of the invention is particularly well suited to use as a bit error rate tester on high speed communication lines because it permits the receiver to synchronize to the transmitted pattern within 2n bits.

  3. DOE Publishes CALiPER Report on Linear (T8) LED Lamps in a 2x4...

    Energy Savers [EERE]

    Linear (T8) LED Lamps in a 2x4 K12-Lensed Troffer DOE Publishes CALiPER Report on Linear (T8) LED Lamps in a 2x4 K12-Lensed Troffer May 2, 2014 - 4:48pm Addthis The U.S. Department ...

  4. Size reduction of high- and low-moisture corn stalks by linear knife grid system

    SciTech Connect (OSTI)

    Womac, A.R. [University of Tennessee; Igathinathane, C. [Mississippi State University (MSU); Sokhansanj, Shahabaddine [ORNL; Narayan, S. [First American Scientific Co.

    2009-04-01

    High- and low-moisture corn stalks were tested using a linear knife grid size reduction device developed for first-stage size reduction. The device was used in conjunction with a universal test machine that quantified shearing stress and energy characteristics for forcing a bed of corn stalks through a grid of sharp knives. No published engineering performance data for corn stover with similar devices are available to optimize performance; however, commercial knife grid systems exist for forage size reduction. From the force displacement data, mean and maximum ultimate shear stresses, cumulative and peak mass-based cutting energies for corn stalks, and mean new surface area-based cutting energies were determined from 4 5 refill runs at two moisture contents (78.8% and 11.3% wet basis), three knife grid spacings (25.4, 50.8, and 101.6 mm), and three bed depths (50.8, 101.6, and 152.4 mm). In general, the results indicated that peak failure load, ultimate shear stress, and cutting energy values varied directly with bed depth and inversely with knife grid spacing. Mean separation analysis established that high- and low-moisture conditions and bed depths 101.6 mm did not differ significantly (P < 0.05) for ultimate stress and cutting energy values, but knife grid spacing were significantly different. Linear knife grid cutting energy requirements for both moisture conditions of corn stalks were much smaller than reported cutting energy requirements. Ultimate shear stress and cutting energy results of this research should aid the engineering design of commercial scale linear knife gird size reduction equipment for various biomass feedstocks.

  5. ANALYSIS OF QUIET-SUN INTERNETWORK MAGNETIC FIELDS BASED ON LINEAR POLARIZATION SIGNALS

    SciTech Connect (OSTI)

    Orozco Suarez, D.; Bellot Rubio, L. R.

    2012-05-20

    We present results from the analysis of Fe I 630 nm measurements of the quiet Sun taken with the spectropolarimeter of the Hinode satellite. Two data sets with noise levels of 1.2 Multiplication-Sign 10{sup -3} and 3 Multiplication-Sign 10{sup -4} are employed. We determine the distribution of field strengths and inclinations by inverting the two observations with a Milne-Eddington model atmosphere. The inversions show a predominance of weak, highly inclined fields. By means of several tests we conclude that these properties cannot be attributed to photon noise effects. To obtain the most accurate results, we focus on the 27.4% of the pixels in the second data set that have linear polarization amplitudes larger than 4.5 times the noise level. The vector magnetic field derived for these pixels is very precise because both circular and linear polarization signals are used simultaneously. The inferred field strength, inclination, and filling factor distributions agree with previous results, supporting the idea that internetwork (IN) fields are weak and very inclined, at least in about one quarter of the area occupied by the IN. These properties differ from those of network fields. The average magnetic flux density and the mean field strength derived from the 27.4% of the field of view with clear linear polarization signals are 16.3 Mx cm{sup -2} and 220 G, respectively. The ratio between the average horizontal and vertical components of the field is approximately 3.1. The IN fields do not follow an isotropic distribution of orientations.

  6. Detection of foreign body using fast thermoacoustic tomography with a multielement linear transducer array

    SciTech Connect (OSTI)

    Nie Liming; Xing Da; Yang Diwu; Zeng Lvming; Zhou Quan

    2007-04-23

    Current imaging modalities face challenges in clinical applications due to limitations in resolution or contrast. Microwave-induced thermoacoustic imaging may provide a complementary modality for medical imaging, particularly for detecting foreign objects due to their different absorption of electromagnetic radiation at specific frequencies. A thermoacoustic tomography system with a multielement linear transducer array was developed and used to detect foreign objects in tissue. Radiography and thermoacoustic images of objects with different electromagnetic properties, including glass, sand, and iron, were compared. The authors' results demonstrate that thermoacoustic imaging has the potential to become a fast method for surgical localization of occult foreign objects.

  7. Linear optics measurements and corrections using an AC dipole in RHIC

    SciTech Connect (OSTI)

    Wang, G.; Bai, M.; Yang, L.

    2010-05-23

    We report recent experimental results on linear optics measurements and corrections using ac dipole. In RHIC 2009 run, the concept of the SVD correction algorithm is tested at injection energy for both identifying the artificial gradient errors and correcting it using the trim quadrupoles. The measured phase beatings were reduced by 30% and 40% respectively for two dedicated experiments. In RHIC 2010 run, ac dipole is used to measure {beta}* and chromatic {beta} function. For the 0.65m {beta}* lattice, we observed a factor of 3 discrepancy between model and measured chromatic {beta} function in the yellow ring.

  8. A free-piston Stirling engine/linear alternator controls and load interaction test facility

    SciTech Connect (OSTI)

    Rauch, J.S.; Kankam, M.D.; Santiago, W.; Madi, F.J.

    1992-08-01

    A test facility at LeRC was assembled for evaluating free-piston Stirling engine/linear alternator control options, and interaction with various electrical loads. This facility is based on a 'SPIKE' engine/alternator. The engine/alternator, a multi-purpose load system, a digital computer based load and facility control, and a data acquisition system with both steady-periodic and transient capability are described. Preliminary steady-periodic results are included for several operating modes of a digital AC parasitic load control. Preliminary results on the transient response to switching a resistive AC user load are discussed.

  9. Method for linearizing deflection of a MEMS device using binary electrodes and voltage modulation

    DOE Patents [OSTI]

    Horenstein, Mark N. [West Roxbury, MA

    2008-06-10

    A micromechanical device comprising one or more electronically movable structure sets comprising for each set a first electrode supported on a substrate and a second electrode supported substantially parallel from said first electrode. Said second electrode is movable with respect to said first electrode whereby an electric potential applied between said first and second electrodes causing said second electrode to move relative to said first electrode a distance X, (X), where X is a nonlinear function of said potential, (V). Means are provided for linearizing the relationship between V and X.

  10. Investigations of non-linear polymers as high performance lubricant additives

    SciTech Connect (OSTI)

    Robinson, Joshua W.; Bhattacharya, Priyanka; Qu, Jun; Bays, J. Timothy; Cosimbescu, Lelia

    2015-03-22

    Off-the-shelf available engine oils contain an assortment of additives that increase the performance of base oils and maximize the overall efficiency of the machine. With ever increasing requirements for fuel efficiency, the demand for novel materials that outperform older generations is also on the rise. One approach towards increasing overall efficiency is to reduce internal friction and wear in an engine. From an additive approach, this is typically achieved by altering the bulk oil’s viscosity at high temperatures via polymers. In general, the hydrodynamic volume of polymers increase (expand) at elevated temperatures and decrease (contract/deflate) with declining temperatures and this effect is enhanced be carefully designing specific structures and architectures. The natural thinning tendency of base oil with increasing temperatures is in part mitigated by the expansion of the macromolecules added, and the overall effect is decreasing the viscosity losses at high temperatures. Traditional polymer architectures vary from linear to dendritic, where linear polymers of the same chemical composition and molecular weight to its dendritic counterpart will undergo a more significant free volume change in solution with regards to temperature changes. This advantage has been exploited in the literature towards the production of viscosity modifiers. However, one major disadvantage of linear polymers is degradation due to mechanical shear forces and high temperatures causing a shorter additive lifetime. Dendrimers on the other hand are known to demonstrate superior robustness to shear degradation when compared to their respective linear counterparts. An additional advantage of the dendritic architecture is the ability to tailor the peripheral end-groups towards influencing polymer-solvent and/or polymer-surface interactions. Comb-burst hyperbranched polymers are a hybrid of the aforementioned architectures and provide several compromises between the traditional structures including the tailoring of peripheral functional groups, conformational flexibility via lipophilic long chain linkers, and a readily available synthesis amenable to scale-up. In the following communication, the synthesis of an aryl comb-burst hyperbranched polymer will be described. Some of the challenges we had to overcome are being highlighted, such as efforts towards increasing lipophilicity of the molecule via changes in saturated carbon content, controlling polymerization conditions to control average molecular weight and degree of branching. In addition, trends in viscosity modification of the bulk oil and wear/friction studies will be discussed.

  11. Parametric instability of plasmas produced by linearly polarized microwave pulsed fields

    SciTech Connect (OSTI)

    Shokri, B.; Ghorbanalilu, M.

    2005-04-15

    After analyzing the interaction of an intense linearly polarized microwave, field weaker than atomic field, with a dilute gas, the production of a plasma is studied. It is shown that the electron distribution function obtained is nonequilibrium and anisotropic. By considering the interaction of the high-frequency electric field with the produced plasma the dispersion relation of oscillations in the produced plasma is obtained. The parametric instability is studied for the produced plasma when instability frequency is higher than ion plasma frequency. Calculations show that the harmonic generation takes place in the produced plasma.

  12. Linear beam raster magnet driver based on H-bridge technique

    DOE Patents [OSTI]

    Sinkine, Nikolai I.; Yan, Chen; Apeldoorn, Cornelis; Dail, Jeffrey Glenn; Wojcik, Randolph Frank; Gunning, William

    2006-06-06

    An improved raster magnet driver for a linear particle beam is based on an H-bridge technique. Four branches of power HEXFETs form a two-by-two switch. Switching the HEXFETs in a predetermined order and at the right frequency produces a triangular current waveform. An H-bridge controller controls switching sequence and timing. The magnetic field of the coil follows the shape of the waveform and thus steers the beam using a triangular rather than a sinusoidal waveform. The system produces a raster pattern having a highly uniform raster density distribution, eliminates target heating from non-uniform raster density distributions, and produces higher levels of beam current.

  13. On linear groups of degree 2 over a finite commutative ring

    SciTech Connect (OSTI)

    Bashkirov, Evgenii L.; Eser, Hasan

    2014-08-20

    Let p > 3 be a prime number and F{sub p} be a field of p elements. Let K be a commutative and associative ring obtained by adjoining to F{sub p} an element ? such that ? satisfies a polynomial over F{sub p} and a polynomial of the least degree whose root is ? can be written as a product of distinct polynomials irreducible over F{sub p}. We prove that the special linear group SL{sub 2}(K) is generated by two elementary transvections ( (table) ), ( (table) )

  14. High efficiency, low frequency linear compressor proposed for Gifford-McMahon and pulse tube cryocoolers

    SciTech Connect (OSTI)

    Hhne, Jens

    2014-01-29

    In order to reduce the amount of greenhouse gas emissions, which are most likely the cause of substantial global warming, a reduction of overall energy consumption is crucial. Low frequency Gifford-McMahon and pulse tube cryocoolers are usually powered by a scroll compressor together with a rotary valve. It has been theoretically shown that the efficiency losses within the rotary valve can be close to 50%{sup 1}. In order to eliminate these losses we propose to use a low frequency linear compressor, which directly generates the pressure wave without using a rotary valve. First results of this development will be presented.

  15. Frequency Stabilization in Non-linear MEMS and NEMS Oscillators (IN-11-087)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    - Energy Innovation Portal Find More Like This Return to Search Frequency Stabilization in Non-linear MEMS and NEMS Oscillators (IN-11-087) A New Strategy for Engineering Low-Frequency Noise Oscillators Argonne National Laboratory Contact ANL About This Technology <p> SEM image of one resonator used in our studies (center) and Finite Element Simulations of the dynamic deformation characteristics of the coupled vibrational modes (left and right side).</p> SEM image of one

  16. Measurements of Neutron Induced Cross Sections at the Oak Ridge Electron Linear Accelerator

    SciTech Connect (OSTI)

    Guber, K.H.; Harvey, J.A.; Hill, N.W.; Koehler, P.E.; Leal, L.C.; Sayer, R.O.; Spencer, R.R.

    1999-09-20

    We have used the Oak Ridge Electron Linear Accelerator (ORELA) to measure neutron total and the fission cross sections of 233U in the energy range from 0.36 eV to ~700 keV. We report average fission and total cross sections. Also, we measured the neutron total cross sections of 27Al and Natural chlorine as well as the capture cross section of Al over an energy range from 100 eV up to about 400 keV.

  17. An object oriented design for high performance linear algebra on distributed memory architectures

    SciTech Connect (OSTI)

    Dongarra, J.J. |; Walker, D.W.; Pozo, R.

    1993-12-31

    We describe the design of ScaLAPACK++, an object oriented C++ library for implementing linear algebra computations on distributed memory multicomputers. This package, when complete, will support distributed dense, banded, sparse matrix operations for symmetric, positive-definite, and non-symmetric cases. In ScaLAPACK++ we have employed object oriented design methods to enchance scalability, portability, flexibility, and ease-of-use. We illustrate some of these points by describing the implementation of a right-looking LU factorization for dense systems in ScaLAPACK++.

  18. Electron acceleration by linearly polarized twisted laser pulse with narrow divergence

    SciTech Connect (OSTI)

    Vaziri, Mohammad Sohaily, Sozha; Golshani, Mojtaba; Bahrampour, Alireza

    2015-03-15

    We numerically investigate the vacuum electron acceleration by a high-intensity linearly polarized twisted laser pulse. It is shown that the inherent spiral structure of a Laguerre-Gaussian laser pulse leads to improvement in trapping and acceleration of an electron to energies of the order of GeV in the off-axis case. Also, it is demonstrated that by employing a proper choice of initial injection parameters, the high-energetic electrons with very small scattering angles can be produced.

  19. Linear study of Rayleigh-Taylor instability in a diffusive quantum plasma

    SciTech Connect (OSTI)

    Momeni, Mahdi

    2013-08-15

    The linear Rayleigh-Taylor (RT) instability in an incompressible quantum plasma is investigated on the basis of quantum magnetohydrodynamic model. It is shown that the occurrence of RT instability depends on density-temperature inhomogeneity (characteristic lengths) on one hand, and the system layer size on the other. It is also observed that the combined effects of external magnetic field, diffusivity, and quantum pressure significantly modify the dispersion properties of system in both the parallel and perpendicular directions. For any case, the imaginary and real parts of dispersion relation are presented and the possibility and conditions for the instability growth rate are discussed.

  20. EXPLORING THE VARIABLE SKY WITH LINEAR. III. CLASSIFICATION OF PERIODIC LIGHT CURVES

    SciTech Connect (OSTI)

    Palaversa, Lovro; Eyer, Laurent; Rimoldini, Lorenzo; Ivezi?, eljko; Loebman, Sarah; Hunt-Walker, Nicholas; VanderPlas, Jacob; Westman, David; Becker, Andrew C.; Rudjak, Domagoj; Sudar, Davor; Boi?, Hrvoje; Galin, Mario; Kroflin, Andrea; Mesari?, Martina; Munk, Petra; Vrbanec, Dijana; Sesar, Branimir; Stuart, J. Scott; Srdo?, Gregor; and others

    2013-10-01

    We describe the construction of a highly reliable sample of ?7000 optically faint periodic variable stars with light curves obtained by the asteroid survey LINEAR across 10,000 deg{sup 2} of the northern sky. The majority of these variables have not been cataloged yet. The sample flux limit is several magnitudes fainter than most other wide-angle surveys; the photometric errors range from ?0.03 mag at r = 15 to ?0.20 mag at r = 18. Light curves include on average 250 data points, collected over about a decade. Using Sloan Digital Sky Survey (SDSS) based photometric recalibration of the LINEAR data for about 25 million objects, we selected ?200,000 most probable candidate variables with r < 17 and visually confirmed and classified ?7000 periodic variables using phased light curves. The reliability and uniformity of visual classification across eight human classifiers was calibrated and tested using a catalog of variable stars from the SDSS Stripe 82 region and verified using an unsupervised machine learning approach. The resulting sample of periodic LINEAR variables is dominated by 3900 RR Lyrae stars and 2700 eclipsing binary stars of all subtypes and includes small fractions of relatively rare populations such as asymptotic giant branch stars and SX Phoenicis stars. We discuss the distribution of these mostly uncataloged variables in various diagrams constructed with optical-to-infrared SDSS, Two Micron All Sky Survey, and Wide-field Infrared Survey Explorer photometry, and with LINEAR light-curve features. We find that the combination of light-curve features and colors enables classification schemes much more powerful than when colors or light curves are each used separately. An interesting side result is a robust and precise quantitative description of a strong correlation between the light-curve period and color/spectral type for close and contact eclipsing binary stars (? Lyrae and W UMa): as the color-based spectral type varies from K4 to F5, the median period increases from 5.9 hr to 8.8 hr. These large samples of robustly classified variable stars will enable detailed statistical studies of the Galactic structure and physics of binary and other stars and we make these samples publicly available.

  1. A linear MOSFET regulation system to improve the performance of the booster-ramping power supplies at the APS.

    SciTech Connect (OSTI)

    Feng, G.; Deriy, B.; Wang, J.; Shang, H.; Xu, S.

    2008-01-01

    The APS booster ring uses ramping power supplies to power the sextupole, quadrupole, and dipole magnets as the beam energy ramps up linearly to 7 GeV. Due to the circuit topology used, those supplies are unable to follow the linear ramp to the desired accuracy. The best regulation achieved is 0.5% while 0.1 % is desired. In addition to the unsatisfying regulation, those supplies are sensitive to AC line perturbations and are not able to reject AC line noises higher than a few tens of Hertz. To improve the performance, a linear MOSFET regulation system using paralleled MOSFET devices in series with the power supply is proposed. The system uses a real-time current feedback loop to force the MOSFETs to work in the linear operation mode. By using this linear MOSFET regulator, the voltage drop on MOSFETs, and hence the voltage imposed on magnets, can be regulated very quickly. As a result, the regulation of the magnet current can be improved significantly. Experiments and simulation have been performed to verify the proposed method. Results show that, with the linear regulator, the current regulation can be improved to better than 0.1%. Because of the high bandwidth of the linear regulator, it can reduce the harmonic content in the output current as well as reject the AC line disturbance.

  2. CALiPER Report 21.1. Linear (T8) Lamps in a 2x4 K12-Lensed Troffer

    SciTech Connect (OSTI)

    2014-04-01

    This report focuses on the performance of the same 31 linear LED lamps operated in a typical troffer with a K12 prismatic lens. In general, luminaire efficacy is strongly dictated by lamp efficacy, but the optical system of the luminaire substantially reduces the differences between the luminous intensity distributions of the lamps. While the distributions in the luminaire are similar, the differences remain large enough that workplane illuminance uniformity may be reduced if linear LED lamps with a narrow distribution are used. At the same time, linear LED lamps with a narrower distribution result in slightly higher luminaire efficiency.

  3. Linear analysis on the growth of non-spherical perturbations in supersonic accretion flows

    SciTech Connect (OSTI)

    Takahashi, Kazuya; Yamada, Shoichi

    2014-10-20

    We analyzed the growth of non-spherical perturbations in supersonic accretion flows. We have in mind an application to the post-bounce phase of core-collapse supernovae (CCSNe). Such non-spherical perturbations have been suggested by a series of papers by Arnett, who has numerically investigated violent convections in the outer layers of pre-collapse stars. Moreover, Couch and Ott demonstrated in their numerical simulations that such perturbations may lead to a successful supernova even for a progenitor that fails to explode without fluctuations. This study investigated the linear growth of perturbations during the infall onto a stalled shock wave. The linearized equations are solved as an initial and boundary value problem with the use of a Laplace transform. The background is a Bondi accretion flow whose parameters are chosen to mimic the 15 M {sub ☉} progenitor model by Woosley and Heger, which is supposed to be a typical progenitor of CCSNe. We found that the perturbations that are given at a large radius grow as they flow down to the shock radius; the density perturbations can be amplified by a factor of 30, for example. We analytically show that the growth rate is proportional to l, the index of the spherical harmonics. We also found that the perturbations oscillate in time with frequencies that are similar to those of the standing accretion shock instability. This may have an implication for shock revival in CCSNe, which will be investigated in our forthcoming paper in more detail.

  4. Radiative observables for linearized gravity on asymptotically flat spacetimes and their boundary induced states

    SciTech Connect (OSTI)

    Benini, Marco Dappiaggi, Claudio; Murro, Simone

    2014-08-01

    We discuss the quantization of linearized gravity on globally hyperbolic, asymptotically flat, vacuum spacetimes, and the construction of distinguished states which are both of Hadamard form and invariant under the action of all bulk isometries. The procedure, we follow, consists of looking for a realization of the observables of the theory as a sub-algebra of an auxiliary, non-dynamical algebra constructed on future null infinity ??. The applicability of this scheme is tantamount to proving that a solution of the equations of motion for linearized gravity can be extended smoothly to ??. This has been claimed to be possible provided that a suitable gauge fixing condition, first written by Geroch and Xanthopoulos [Asymptotic simplicity is stable, J. Math. Phys. 19, 714 (1978)], is imposed. We review its definition critically, showing that there exists a previously unnoticed obstruction in its implementation leading us to introducing the concept of radiative observables. These constitute an algebra for which a Hadamard state induced from null infinity and invariant under the action of all spacetime isometries exists and it is explicitly constructed.

  5. CONDUCTION IN LOW MACH NUMBER FLOWS. I. LINEAR AND WEAKLY NONLINEAR REGIMES

    SciTech Connect (OSTI)

    Lecoanet, Daniel; Brown, Benjamin P.; Zweibel, Ellen G.; Burns, Keaton J.; Oishi, Jeffrey S.; Vasil, Geoffrey M.

    2014-12-20

    Thermal conduction is an important energy transfer and damping mechanism in astrophysical flows. Fourier's law, in which the heat flux is proportional to the negative temperature gradient, leading to temperature diffusion, is a well-known empirical model of thermal conduction. However, entropy diffusion has emerged as an alternative thermal conduction model, despite not ensuring the monotonicity of entropy. This paper investigates the differences between temperature and entropy diffusion for both linear internal gravity waves and weakly nonlinear convection. In addition to simulating the two thermal conduction models with the fully compressible Navier-Stokes equations, we also study their effects in the reduced ''soundproof'' anelastic and pseudoincompressible (PI) equations. We find that in the linear and weakly nonlinear regime, temperature and entropy diffusion give quantitatively similar results, although there are some larger errors in the PI equations with temperature diffusion due to inaccuracies in the equation of state. Extrapolating our weakly nonlinear results, we speculate that differences between temperature and entropy diffusion might become more important for strongly turbulent convection.

  6. Quantum chaos of an ion trapped in a linear ion trap

    SciTech Connect (OSTI)

    Berman, Gennady P. [Theoretical Division T-13, and CNLS, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division T-13, and CNLS, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); James, Daniel F. V. [Theoretical Division T-4, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division T-4, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Kamenev, Dimitri I. [Theoretical Division T-13, and CNLS, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States) [Theoretical Division T-13, and CNLS, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Nizhny Novgorod State University, Nizhny Novgorod, 603600, Russia (Russian Federation)

    2000-06-01

    We describe the transition to quantum chaos of an ion trapped in a linear ion trap and interacting with two laser fields. Under the conditions of adiabatic illumination of the upper level of the ion, and when the frequencies of the two laser beams are slightly different, the system is reduced to a quantum linear oscillator interacting with a monochromatic wave. The property of localization over the quantum resonance cells is proposed to exploit in order to facilitate the process of measurement of the probability distribution of an ion on the vibrational levels. In the regime of strong chaos the time-averaged values of the energy and dispersion of energy are computed and compared with the corresponding classical quantities for different values of the perturbation amplitude. In the exact resonance case, the classical analog of the system possesses an infinite inhomogeneous stochastic web. We analyze the quantum dynamics inside the inhomogeneous web. It is shown that the quantum system mimics on average the dynamics of the corresponding classical system. Formation of the quantum resonance cells is illustrated in the case of a finite detuning from the exact resonance, and under increasing of the wave amplitude. The parameters of the model and the initial conditions are close to the real physical situation which can be realized in the system of cold trapped ion perturbed by two lasers fields with close frequencies. (c) 2000 American Institute of Physics.

  7. Linear Free Energy Correlations for Fission Product Release from the Fukushima-Daiichi Nuclear Accident

    SciTech Connect (OSTI)

    Abrecht, David G.; Schwantes, Jon M.

    2015-03-03

    This paper extends the preliminary linear free energy correlations for radionuclide release performed by Schwantes, et al., following the Fukushima-Daiichi Nuclear Power Plant accident. Through evaluations of the molar fractionations of radionuclides deposited in the soil relative to modeled radionuclide inventories, we confirm the source of the radionuclides to be from active reactors rather than the spent fuel pool. Linear correlations of the form ln⁡Χ=-α (ΔG_rxn^° (T_C ))/(RT_C )+β were obtained between the deposited concentration and the reduction potential of the fission product oxide species using multiple reduction schemes to calculate ΔG_rxn^° (T_C ). These models allowed an estimate of the upper bound for the reactor temperatures of T_C between 2130 K and 2220 K, providing insight into the limiting factors to vaporization and release of fission products during the reactor accident. Estimates of the release of medium-lived fission products 90Sr, 121mSn, 147Pm, 144Ce, 152Eu, 154Eu, 155Eu, 151Sm through atmospheric venting and releases during the first month following the accident were performed, and indicate large quantities of 90Sr and radioactive lanthanides were likely to remain in the damaged reactor cores.

  8. Relativistic-Klystron two-beam accelerator as a power source for future linear colliders

    SciTech Connect (OSTI)

    Lidia, S. M.; Anderson, D. E.; Eylon, S.; Henestroza, E.; Vanecek, D. L.; Yu, S. S. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Houck, T. L.; Westenskow, G. A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    1999-05-07

    The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2-kA, 1-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1% energy variation), and a normalized edge emittance of less than 300 pi-mm-mr. The prototype accelerator will be used to study, physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented.

  9. Periodic permanent magnet development for linear collider X-band klystrons

    SciTech Connect (OSTI)

    Sprehn, D.; Caryotakis, G.; Jongewaard, E.; Phillips, R. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)

    1999-05-07

    The Stanford Linear Accelerator Center (SLAC) klystron group is currently designing, fabricating and testing 11.424 GHz klystrons with peak output powers from 50 to 75 MW at 1 to 2 {mu}s rf pulsewidths as part of an effort to realize components necessary for the construction of the Next Linear Collider (NLC). In order to eliminate the projected operational-year energy bill for klystron solenoids, Periodic Permanent Magnet (PPM) focusing has been employed on our latest X-band klystron designs. A PPM beam tester has operated at the same repetition rate, voltage and average beam power required for a 75-MW NLC klystron. Prototype 50 and 75-MW PPM klystrons were built and tested during 1996 and 1997 which operate from 50 to 70 MW at efficiencies greater than 55%. Construction and testing of 75-MW research klystrons will continue while the design and reliability is perfected. This paper will discuss the design of these PPM klystrons and the results of testing to date along with future plans for the development of a low-cost Design for Manufacture (DFM) 75-MW klystron and invitation for industry participation.

  10. Relativistic-Klystron two-beam accelerator as a power source for future linear colliders

    SciTech Connect (OSTI)

    Lidia, S.M.; Anderson, D.E.; Eylon, S.; Henestroza, E.; Vanecek, D.L.; Yu, S.S. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Westenskow, G.A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    1999-05-01

    The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2-kA, 1-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1{percent} energy variation), and a normalized edge emittance of less than 300 pi-mm-mr. The prototype accelerator will be used to study, physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented. {copyright} {ital 1999 American Institute of Physics.}

  11. Periodic permanent magnet development for linear collider X-band klystrons

    SciTech Connect (OSTI)

    Sprehn, D.; Caryotakis, G.; Jongewaard, E.; Phillips, R. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)

    1999-05-01

    The Stanford Linear Accelerator Center (SLAC) klystron group is currently designing, fabricating and testing 11.424 GHz klystrons with peak output powers from 50 to 75 MW at 1 to 2 {mu}s rf pulsewidths as part of an effort to realize components necessary for the construction of the Next Linear Collider (NLC). In order to eliminate the projected operational-year energy bill for klystron solenoids, Periodic Permanent Magnet (PPM) focusing has been employed on our latest X-band klystron designs. A PPM beam tester has operated at the same repetition rate, voltage and average beam power required for a 75-MW NLC klystron. Prototype 50 and 75-MW PPM klystrons were built and tested during 1996 and 1997 which operate from 50 to 70 MW at efficiencies greater than 55{percent}. Construction and testing of 75-MW research klystrons will continue while the design and reliability is perfected. This paper will discuss the design of these PPM klystrons and the results of testing to date along with future plans for the development of a low-cost Design for Manufacture (DFM) 75-MW klystron and invitation for industry participation. {copyright} {ital 1999 American Institute of Physics.}

  12. Relativistic-klystron two-beam accelerator as a power source for future linear colliders

    SciTech Connect (OSTI)

    Anderson, D E; Eylon, S; Henestroza, E; Houck, T L; Lidia, M; Vanecek, D L; Westenskow, G A; Yu, S S

    1998-10-05

    The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2&A, l-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1% energy variation), and a normalized edge emittance of less than 300 pi-mm-n-n. The prototype accelerator will be used to study physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented.

  13. Linear motor drive system for continuous-path closed-loop position control of an object

    DOE Patents [OSTI]

    Barkman, William E. (Oak Ridge, TN)

    1980-01-01

    A precision numerical controlled servo-positioning system is provided for continuous closed-loop position control of a machine slide or platform driven by a linear-induction motor. The system utilizes filtered velocity feedback to provide system stability required to operate with a system gain of 100 inches/minute/0.001 inch of following error. The filtered velocity feedback signal is derived from the position output signals of a laser interferometer utilized to monitor the movement of the slide. Air-bearing slides mounted to a stable support are utilized to minimize friction and small irregularities in the slideway which would tend to introduce positioning errors. A microprocessor is programmed to read command and feedback information and converts this information into the system following error signal. This error signal is summed with the negative filtered velocity feedback signal at the input of a servo amplifier whose output serves as the drive power signal to the linear motor position control coil.

  14. Achieving large linear elasticity and high strength in bulk nanocompsite via synergistic effect

    SciTech Connect (OSTI)

    Hao, Shijie; Cui, Lishan; Guo, Fangmin; Liu, Yinong; Shi, Xiaobin; Jiang, Daqiang; Brown, Dennis E.; Ren, Yang

    2015-03-09

    Elastic strain in bulk metallic materials is usually limited to only a fraction of 1%. Developing bulk metallic materials showing large linear elasticity and high strength has proven to be difficult. Here, based on the synergistic effect between nanowires and orientated martensite NiTi shape memory alloy, we developed an in-situ Nb nanowires -orientated martensitic NiTi matrix composite showing an ultra-large linear elastic strain of 4% and an ultrahigh yield strength of 1.8 GPa. This material also has a high mechanical energy storage efficiency of 96% and a high energy storage density of 36 J/cm that is almost one order of larger than that of spring steel. It is demonstrated that the synergistic effect allows the exceptional mechanical properties of nanowires to be harvested at macro scale and the mechanical properties of matrix to be greatly improved, resulting in these superior properties. This study provides new avenues for developing advanced composites with superior properties by using effective synergistic effect between components.

  15. Validity of the Taylor hypothesis for linear kinetic waves in the weakly collisional solar wind

    SciTech Connect (OSTI)

    Howes, G. G.; Klein, K. G.; TenBarge, J. M.

    2014-07-10

    The interpretation of single-point spacecraft measurements of solar wind turbulence is complicated by the fact that the measurements are made in a frame of reference in relative motion with respect to the turbulent plasma. The Taylor hypothesisthat temporal fluctuations measured by a stationary probe in a rapidly flowing fluid are dominated by the advection of spatial structures in the fluid rest frameis often assumed to simplify the analysis. But measurements of turbulence in upcoming missions, such as Solar Probe Plus, threaten to violate the Taylor hypothesis, either due to slow flow of the plasma with respect to the spacecraft or to the dispersive nature of the plasma fluctuations at small scales. Assuming that the frequency of the turbulent fluctuations is characterized by the frequency of the linear waves supported by the plasma, we evaluate the validity of the Taylor hypothesis for the linear kinetic wave modes in the weakly collisional solar wind. The analysis predicts that a dissipation range of solar wind turbulence supported by whistler waves is likely to violate the Taylor hypothesis, while one supported by kinetic Alfvn waves is not.

  16. Zeroth-order design report for the next linear collider. Volume 2

    SciTech Connect (OSTI)

    Raubenheimer, T.O.

    1996-05-01

    This Zeroth-Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The ``design`` presented here is not fully engineered in any sense, but to be assured that the NLC can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume II covers the following: collimation systems; IP switch and big bend; final focus; the interaction region; multiple bunch issues; control systems; instrumentation; machine protection systems; NLC reliability considerations; NLC conventional facilities. Also included are four appendices on the following topics: An RF power source upgrade to the NLC; a second interaction region for gamma-gamma, gamma-electron; ground motion: theory and measurement; and beam-based feedback: theory and implementation.

  17. Zeroth-order design report for the next linear collider. Volume 1

    SciTech Connect (OSTI)

    Raubenheimer, T.O.

    1996-05-01

    This Zeroth Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The design presented here is not fully engineered in any sense, but to be assured that the NLC can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume one covers the following: the introduction; electron source; positron source; NLC damping rings; bunch compressors and prelinac; low-frequency linacs and compressors; main linacs; design and dynamics; and RF systems for main linacs.

  18. CALiPER Application Summary Report 21. Linear (T8) LED Lamps

    SciTech Connect (OSTI)

    2014-03-01

    This report focuses on the bare lamp performance of 31 linear LED lamps intended as an alternative to T8 fluorescent lamps. Data obtained in accordance with IES LM-79-08 indicated that the mean efficacy is similar to that of fluorescent lamps, but that lumen output is often much lower. This presents a situation where something must change in order for energy savings and equivalent illumination levels to be achieved simultaneously. In this case, the luminous intensity distribution of all the tested lamps was directional or semi-directional, rather than omnidirectional. Also discussed in this report are several issues related to the electrical configuration of the lamps, such as the required socket types and power feed location. While no configuration is necessarily better, the multitude of options can make specifying and installing linear LED lamps more difficult, with the potential for safety issues. Similarly, the variety of color and power quality attributes adds a layer of complexity to the specification process. Many products offered good or excellent quality attributes, but some did not and thus could be perceived as inferior to fluorescent lamps in some installations.

  19. Linear-scaling implementation of the direct random-phase approximation

    SciTech Connect (OSTI)

    Kllay, Mihly

    2015-05-28

    We report the linear-scaling implementation of the direct random-phase approximation (dRPA) for closed-shell molecular systems. As a bonus, linear-scaling algorithms are also presented for the second-order screened exchange extension of dRPA as well as for the second-order MllerPlesset (MP2) method and its spin-scaled variants. Our approach is based on an incremental scheme which is an extension of our previous local correlation method [Rolik et al., J. Chem. Phys. 139, 094105 (2013)]. The approach extensively uses local natural orbitals to reduce the size of the molecular orbital basis of local correlation domains. In addition, we also demonstrate that using natural auxiliary functions [M. Kllay, J. Chem. Phys. 141, 244113 (2014)], the size of the auxiliary basis of the domains and thus that of the three-center Coulomb integral lists can be reduced by an order of magnitude, which results in significant savings in computation time. The new approach is validated by extensive test calculations for energies and energy differences. Our benchmark calculations also demonstrate that the new method enables dRPA calculations for molecules with more than 1000 atoms and 10?000 basis functions on a single processor.

  20. SLFP: A stochastic linear fractional programming approach for sustainable waste management

    SciTech Connect (OSTI)

    Zhu, H.; Huang, G.H.

    2011-12-15

    Highlights: > A new fractional programming (SLFP) method is developed for waste management. > SLFP can solve ratio optimization problems associated with random inputs. > A case study of waste flow allocation demonstrates its applicability. > SLFP helps compare objectives of two aspects and reflect system efficiency. > This study supports in-depth analysis of tradeoffs among multiple system criteria. - Abstract: A stochastic linear fractional programming (SLFP) approach is developed for supporting sustainable municipal solid waste management under uncertainty. The SLFP method can solve ratio optimization problems associated with random information, where chance-constrained programming is integrated into a linear fractional programming framework. It has advantages in: (1) comparing objectives of two aspects, (2) reflecting system efficiency, (3) dealing with uncertainty expressed as probability distributions, and (4) providing optimal-ratio solutions under different system-reliability conditions. The method is applied to a case study of waste flow allocation within a municipal solid waste (MSW) management system. The obtained solutions are useful for identifying sustainable MSW management schemes with maximized system efficiency under various constraint-violation risks. The results indicate that SLFP can support in-depth analysis of the interrelationships among system efficiency, system cost and system-failure risk.

  1. Comparative study of microwave radiation-induced magnetoresistive oscillations induced by circularly- and linearly- polarized photo-excitation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ye, Tianyu; Liu, Han -Chun; Wang, Zhuo; Wegscheider, W.; Mani, Ramesh G.

    2015-10-09

    A comparative study of the radiation-induced magnetoresistance oscillations in the high mobility GaAs/AlGaAs heterostructure two dimensional electron system (2DES) under linearly- and circularly- polarized microwave excitation indicates a profound difference in the response observed upon rotating the microwave launcher for the two cases, although circularly polarized microwave radiation induced magnetoresistance oscillations observed at low magnetic fields are similar to the oscillations observed with linearly polarized radiation. For the linearly polarized radiation, the magnetoresistive response is a strong sinusoidal function of the launcher rotation (or linear polarization) angle, θ. As a result, for circularly polarized radiation, the oscillatory magnetoresistive response ismore » hardly sensitive to θ.« less

  2. A Nth-order linear algorithm for extracting diffuse correlation spectroscopy blood flow indices in heterogeneous tissues

    SciTech Connect (OSTI)

    Shang, Yu; Yu, Guoqiang

    2014-09-29

    Conventional semi-infinite analytical solutions of correlation diffusion equation may lead to errors when calculating blood flow index (BFI) from diffuse correlation spectroscopy (DCS) measurements in tissues with irregular geometries. Very recently, we created an algorithm integrating a Nth-order linear model of autocorrelation function with the Monte Carlo simulation of photon migrations in homogenous tissues with arbitrary geometries for extraction of BFI (i.e., αD{sub B}). The purpose of this study is to extend the capability of the Nth-order linear algorithm for extracting BFI in heterogeneous tissues with arbitrary geometries. The previous linear algorithm was modified to extract BFIs in different types of tissues simultaneously through utilizing DCS data at multiple source-detector separations. We compared the proposed linear algorithm with the semi-infinite homogenous solution in a computer model of adult head with heterogeneous tissue layers of scalp, skull, cerebrospinal fluid, and brain. To test the capability of the linear algorithm for extracting relative changes of cerebral blood flow (rCBF) in deep brain, we assigned ten levels of αD{sub B} in the brain layer with a step decrement of 10% while maintaining αD{sub B} values constant in other layers. Simulation results demonstrate the accuracy (errors < 3%) of high-order (N ≥ 5) linear algorithm in extracting BFIs in different tissue layers and rCBF in deep brain. By contrast, the semi-infinite homogenous solution resulted in substantial errors in rCBF (34.5% ≤ errors ≤ 60.2%) and BFIs in different layers. The Nth-order linear model simplifies data analysis, thus allowing for online data processing and displaying. Future study will test this linear algorithm in heterogeneous tissues with different levels of blood flow variations and noises.

  3. The pulsed linear induction motor concept for high-speed trains

    SciTech Connect (OSTI)

    Turman, B.N.; Marder, B.M.; Rohwein, G.J.; Aeschliman, D.P.; Kelley, J.B.; Cowan, M.; Zimmerman, R.M.

    1995-06-01

    The SERAPBIM (SEgmented RAil PHased Induction Motor) concept is a linear induction motor concept which uses rapidly-pulsed magnetic fields and a segmented reaction rail, as opposed to low-frequency fields and continuous reaction rails found in conventional linear induction motors. These improvements give a high-traction, compact, and efficient linear motor that has potential for advanced high speed rail propulsion. In the SERAPBIM concept, coils on the vehicle push against a segmented aluminum rail, which is mounted on the road bed. Current is pulsed as the coils cross an edge of the segmented rail, inducing surface currents which repel the coil. The coils must be pulsed in synchronization with the movement by reaction rail segments. This is provided by a sense-and-fire circuit that controls the pulsing of the power modulators. Experiments were conducted to demonstrate the feasibility of the pulsed induction motor and to collect data that could be used for scaling calculations. A 14.4 kg aluminum plate was accelerated down a 4 m track to speeds of over 15 m/sec with peak thrust up to 18 kN per coilset. For a trainset capable of 200 mph speed, the SERAPHIM concept design is based on coils which are each capable of producing up to 3.5 kN thrust, and 30 coil pairs are mounted on each power car. Two power cars, one at each end of the train, provide 6 MW from two gas turbine prime power units. The thrust is about 210.000 N and is essentially constant up to 200 km/hr since wheel slippage does not limit thrust as with conventional wheeled propulsion. A key component of the SERAPHIM concept is the use of passive wheel-on-rah support for the high speed vehicle. Standard steel wheels are capable of handling over 200 mph. The SERAPHIM cost is comparable to that for steel-wheel high-speed rail, and about 10% to 25% of the projected costs for a comparable Maglev system.

  4. Cosmic bubble and domain wall instabilities I: parametric amplification of linear fluctuations

    SciTech Connect (OSTI)

    Braden, Jonathan; Bond, J. Richard; Mersini-Houghton, Laura

    2015-03-03

    This is the first paper in a series where we study collisions of nucleated bubbles taking into account the effects of small initial (quantum) fluctuations in a fully 3+1-dimensional setting. In this paper, we consider the evolution of linear fluctuations around highly symmetric though inhomogeneous backgrounds. In particular, we demonstrate that a large degree of asymmetry develops over time from tiny initial fluctuations superposed upon planar and SO(2,1) symmetric backgrounds. These fluctuations are inevitable consequences of zero-point vacuum oscillations, so excluding them by enforcing a high degree of spatial symmetry is inconsistent in a quantum treatment. To simplify the analysis we consider the limit of two colliding planar walls, with mode functions for the fluctuations characterized by the wavenumber transverse to the collision direction and a longitudinal shape along the collision direction x, which we solve for. In the linear regime, the fluctuations obey a linear wave equation with a time- and space-dependent mass m{sub eff}(x,t). In situations where the walls collide multiple times, m{sub eff} oscillates in time. We use Floquet theory to study the evolution of the fluctuations and generalize the calculations familiar from the preheating literature to the case with many coupled degrees of freedom. The inhomogeneous case has bands of unstable transverse wavenumbers k{sub ⊥} whose corresponding mode functions grow exponentially. By examining the detailed spatial structure of the mode functions in x, we identify both broad and narrow parametric resonance generalizations of the homogeneous m{sub eff}(t) case of preheating. The unstable k{sub ⊥} modes are longitudinally localized, yet can be described as quasiparticles in the Bogoliubov sense. We define an effective occupation number and show they are created in bursts for the case of well-defined collisions in the background. The transverse-longitudinal coupling accompanying nonlinearity radically breaks this localized particle description, with nonseparable 3D modes arising that will be studied in subsequent papers.

  5. MULTI-SPACECRAFT OBSERVATIONS OF LINEAR MODES AND SIDEBAND WAVES IN ION-SCALE SOLAR WIND TURBULENCE

    SciTech Connect (OSTI)

    Perschke, Christopher; Motschmann, Uwe; Narita, Yasuhito; Glassmeier, Karl-Heinz

    2014-10-01

    In the scenario of weak turbulence, energy is believed to be cascaded from smaller to larger wave numbers and frequencies due to weak wave-wave interactions. Based on its perturbative treatment one may regard plasma turbulence as a superposition of linear modes (or normal modes) and sideband waves (or nonlinear modes). In this study, we use magnetic field and plasma measurements of nine solar wind events obtained by the Cluster spacecraft and make extensive use of a high-resolution wave vector analysis method, the Multi-point Signal Resonator technique, to find frequencies and wave vectors of discrete modes on ion kinetic scales in the plasma rest frame. The primarily unstructured wave observations in the frequency-wave number diagram are classified into three distinct linear modes (proton Bernstein modes, helium-alpha Bernstein modes, and kinetic Alfvn waves) and the sideband waves by comparing with the dispersion relations derived theoretically from linear Vlasov theory using observational values of the plasma parameter beta and the propagation angle from the mean magnetic field. About 60% of the observed discrete modes can be explained by the linear modes, primarily as the proton Bernstein and the kinetic Alfvn waves, within the frequency uncertainties, while the rest of the population (about 40%) cannot be classified as linear modes due to the large deviation from dispersion relations. We conclude that both the linear modes and sideband wave components are needed to construct the wave picture of solar wind turbulence on ion-kinetic scales.

  6. Non Linear Analyses for the Evaluation of Seismic Behavior of Mixed R.C.-Masonry Structures

    SciTech Connect (OSTI)

    Liberatore, Laura; Tocci, Cesare; Masiani, Renato

    2008-07-08

    In this work the seismic behavior of masonry buildings with mixed structural system, consisting of perimeter masonry walls and internal r.c. frames, is studied by means of non linear static (pushover) analyses. Several aspects, like the distribution of seismic action between masonry and r.c. elements, the local and global behavior of the structure, the crisis of the connections and the attainment of the ultimate strength of the whole structure are examined. The influence of some parameters, such as the masonry compressive and tensile strength, on the structural behavior is investigated. The numerical analyses are also repeated on a building in which the r.c. internal frames are replaced with masonry walls.

  7. Multiple-Input Multiple-Output (MIMO) Linear Systems Extreme Inputs/Outputs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Smallwood, David O.

    2007-01-01

    A linear structure is excited at multiple points with a stationary normal random process. The response of the structure is measured at multiple outputs. If the autospectral densities of the inputs are specified, the phase relationships between the inputs are derived that will minimize or maximize the trace of the autospectral density matrix of the outputs. If the autospectral densities of the outputs are specified, the phase relationships between the outputs that will minimize or maximize the trace of the input autospectral density matrix are derived. It is shown that other phase relationships and ordinary coherence less than one willmore » result in a trace intermediate between these extremes. Least favorable response and some classes of critical response are special cases of the development. It is shown that the derivation for stationary random waveforms can also be applied to nonstationary random, transients, and deterministic waveforms.« less

  8. Kinetic simulations and reduced modeling of longitudinal sideband instabilities in non-linear electron plasma waves

    SciTech Connect (OSTI)

    Brunner, S. Hausammann, L.; Berger, R. L. Cohen, B. I.; Valeo, E. J.

    2014-10-15

    Kinetic Vlasov simulations of one-dimensional finite amplitude Electron Plasma Waves are performed in a multi-wavelength long system. A systematic study of the most unstable linear sideband mode, in particular its growth rate ? and quasi- wavenumber ?k, is carried out by scanning the amplitude and wavenumber of the initial wave. Simulation results are successfully compared against numerical and analytical solutions to the reduced model by Kruer et al. [Phys. Rev. Lett. 23, 838 (1969)] for the Trapped Particle Instability (TPI). A model recently suggested by Dodin et al. [Phys. Rev. Lett. 110, 215006 (2013)], which in addition to the TPI accounts for the so-called Negative Mass Instability because of a more detailed representation of the trapped particle dynamics, is also studied and compared with simulations.

  9. Kinetic simulations and reduced modeling of longitudinal sideband instabilities in non-linear electron plasma waves

    SciTech Connect (OSTI)

    Brunner, S.; Berger, R. L.; Cohen, B. I.; Hausammann, L.; Valeo, E. J.

    2014-10-01

    Kinetic Vlasov simulations of one-dimensional finite amplitude Electron Plasma Waves are performed in a multi-wavelength long system. A systematic study of the most unstable linear sideband mode, in particular its growth rate ? and quasi- wavenumber ?k, is carried out by scanning the amplitude and wavenumber of the initial wave. Simulation results are successfully compared against numerical and analytical solutions to the reduced model by Kruer et al. [Phys. Rev. Lett. 23, 838 (1969)] for the Trapped Particle Instability (TPI). A model recently suggested by Dodin et al. [Phys. Rev. Lett. 110, 215006 (2013)], which in addition to the TPI accounts for the so-called Negative Mass Instability because of a more detailed representation of the trapped particle dynamics, is also studied and compared with simulations.

  10. Parameter choices for a muon recirculating linear accelerator from 5 to 63 GeV

    SciTech Connect (OSTI)

    Berg, J. S.

    2014-06-19

    A recirculating linear accelerator (RLA) has been proposed to accelerate muons from 5 to 63 GeV for a muon collider. It should be usable both for a Higgs factory and as a stage for a higher energy collider. First, the constraints due to the beam loading are computed. Next, an expression for the longitudinal emittance growth to lowest order in the longitudinal emittance is worked out. After finding the longitudinal expression, a simplified model that describes the arcs and their approximate expression for the time of flight dependence on energy in those arcs is found. Finally, these results are used to estimate the parameters required for the RLA arcs and the linac phase.

  11. Neutron source, linear-accelerator fuel enricher and regenerator and associated methods

    DOE Patents [OSTI]

    Steinberg, Meyer; Powell, James R.; Takahashi, Hiroshi; Grand, Pierre; Kouts, Herbert

    1982-01-01

    A device for producing fissile material inside of fabricated nuclear elements so that they can be used to produce power in nuclear power reactors. Fuel elements, for example, of a LWR are placed in pressure tubes in a vessel surrounding a liquid lead-bismuth flowing columnar target. A linear-accelerator proton beam enters the side of the vessel and impinges on the dispersed liquid lead-bismuth columns and produces neutrons which radiate through the surrounding pressure tube assembly or blanket containing the nuclear fuel elements. These neutrons are absorbed by the natural fertile uranium-238 elements and are transformed to fissile plutonium-239. The fertile fuel is thus enriched in fissile material to a concentration whereby they can be used in power reactors. After use in the power reactors, dispensed depleted fuel elements can be reinserted into the pressure tubes surrounding the target and the nuclear fuel regenerated for further burning in the power reactor.

  12. Quasi-linear analysis of the extraordinary electron wave destabilized by runaway electrons

    SciTech Connect (OSTI)

    Pokol, G. I.; Kmr, A.; Budai, A.; Stahl, A.; Flp, T.

    2014-10-15

    Runaway electrons with strongly anisotropic distributions present in post-disruption tokamak plasmas can destabilize the extraordinary electron (EXEL) wave. The present work investigates the dynamics of the quasi-linear evolution of the EXEL instability for a range of different plasma parameters using a model runaway distribution function valid for highly relativistic runaway electron beams produced primarily by the avalanche process. Simulations show a rapid pitch-angle scattering of the runaway electrons in the high energy tail on the 1001000??s time scale. Due to the wave-particle interaction, a modification to the synchrotron radiation spectrum emitted by the runaway electron population is foreseen, exposing a possible experimental detection method for such an interaction.

  13. Characterization of radial turbulent fluxes in the Santander linear plasma machine

    SciTech Connect (OSTI)

    Mier, J. A. Anabitarte, E.; Sentes, J. M.; Snchez, R.; Newman, D. E.; Castellanos, O. F.; Milligen, B. Ph. van

    2014-05-15

    It is shown that the statistical and correlation properties of the local turbulent flux measured at different radial locations of the cold, weakly ionized plasmas inside the Santander Linear Plasma Machine [Castellanos et al., Plasma Phys. Control. Fusion 47, 2067 (2005)] are consistent with diffusive-like transport dynamics. This is in contrast to the dynamical behavior inferred from similar measurements taken in hotter, fully ionized tokamak and stellarator edge plasmas, in which long-term correlations and other features characteristic of complex, non-diffusive transport dynamics have been reported in the past. These results may shed some light on a recent controversy regarding the possible universality of the dynamics of turbulent transport in magnetized plasmas.

  14. Non-linear Conjugate Gradient Time-Domain Controlled Inversion Source

    Energy Science and Technology Software Center (OSTI)

    2006-11-16

    Software that simulates and inverts time-domain electromagnetic field data for subsurface electrical properties (electrical conductivity) of geological media. The software treats data produced by a step-wise source signal from either galvanic (grounded wires) or inductive (magnetic loops) sources. The inversion process is carried inductive (magnetic loops) sources. The inversion process is carried out using a non-linear conjugate gradient optimization scheme, which minimizes the misfit between field data and model data using a least squares criteria.more » The software is an upgrade from the code TEM3D ver. 2.0. The upgrade includes the following components: (1) Improved (faster)memory access during gradient computation. (2) Data parellelization scheme: Multiple transmitters (sources) can be distributed accross several banks of processors (daa-planes). Similarly, the receivers of each source are also distributed accross the corresponding data-plane. (3) Improved data-IO.« less

  15. ANALYSIS OF HIGH FIELD NON-LINEAR LOSSES ON SRF SURFACES DUE TO SPECIFIC TOPOGRAPHIC ROUGHNESS

    SciTech Connect (OSTI)

    Chen Xu,Charles Reece,Michael Kelley

    2012-07-01

    The high-field performance of SRF cavities will eventually be limited by the realization of fundamental material limits, whether it is Hc1 or Hsh, or some derivative thereof, at which the superconductivity is lost. Before reaching this fundamental field limit at the macro level, it must be encountered at localized, perhaps microscopic, sites of field enhancement due to local topography. If such sites are small enough, they may produce thermally stabilized normal-conducting regions which contribute non-linear losses when viewed from the macro resonant field perspective, and thus produce degradation in Q0. We have undertaken a calculation of local surface magnetic field enhancement from specific fine topographic structure by conformal mapping method and numerically. A solution of the resulting normal conducting volume has been derived and the corresponding RF Ohmic loss simulated.

  16. Structure/Function Studies of Proteins Using Linear Scaling Quantum Mechanical Methodologies

    SciTech Connect (OSTI)

    Merz, K. M.

    2004-07-19

    We developed a linear-scaling semiempirical quantum mechanical (QM) program (DivCon). Using DivCon we can now routinely carry out calculations at the fully QM level on systems containing up to about 15 thousand atoms. We also implemented a Poisson-Boltzmann (PM) method into DivCon in order to compute solvation free energies and electrostatic properties of macromolecules in solution. This new suite of programs has allowed us to bring the power of quantum mechanics to bear on important biological problems associated with protein folding, drug design and enzyme catalysis. Hence, we have garnered insights into biological systems that have been heretofore impossible to obtain using classical simulation techniques.

  17. Phase-controllable spin wave generation in iron garnet by linearly polarized light pulses

    SciTech Connect (OSTI)

    Yoshimine, Isao; Iida, Ryugo; Shimura, Tsutomu; Satoh, Takuya; Stupakiewicz, Andrzej; Maziewski, Andrzej

    2014-07-28

    A phase-controlled spin wave was non-thermally generated in bismuth-doped rare-earth iron garnet by linearly polarized light pulses. We controlled the initial phase of the spin wave continuously within a range of 180 by changing the polarization azimuth of the excitation light. The azimuth dependences of the initial phase and amplitude of the spin wave were attributed to a combination of the inverse Cotton-Mouton effect and photoinduced magnetic anisotropy. Temporally and spatially resolved spin wave propagation was observed with a CCD camera, and the waveform was in good agreement with calculations. A nonlinear effect of the spin excitation was observed for excitation fluences higher than 100 mJ/cm{sup 2}.

  18. Acoustically determined linear piezoelectric response of lithium niobate up to 1100?V

    SciTech Connect (OSTI)

    Patel, N.; Branch, D. W.; Cular, S.; Schamiloglu, E.

    2014-04-21

    We present a method to measure high voltages using the piezoelectric crystal lithium niobate without using voltage dividers. A 36 Y-X cut lithium niobate crystal was coupled to two acoustic transducers, where direct current voltages were applied from 1281100?V. The time-of-flight through the crystal was determined to be linearly dependent on the applied voltage. A model was developed to predict the time-delay in response to the applied voltage. The results show a sensitivity of 17 fs/V with a measurement error of 1 fs/V was achievable using this method. The sensitivity of this method can be increased by measuring the acoustic wave after multiple passes through the crystal. This method has many advantages over traditional techniques such as: favorable scalability for larger voltages, ease of use, cost effectiveness, and compactness.

  19. Off-resonance energy absorption in a linear Paul trap due to mass selective resonant quenching

    SciTech Connect (OSTI)

    Sivarajah, I.; Goodman, D. S.; Wells, J. E.; Smith, W. W.; Narducci, F. A.

    2013-11-15

    Linear Paul traps (LPT) are used in many experimental studies such as mass spectrometry, atom-ion collisions, and ion-molecule reactions. Mass selective resonant quenching (MSRQ) is implemented in LPT either to identify a charged particle's mass or to remove unwanted ions from a controlled experimental environment. In the latter case, MSRQ can introduce undesired heating to co-trapped ions of different mass, whose secular motion is off resonance with the quenching ac field, which we call off-resonance energy absorption (OREA). We present simulations and experimental evidence that show that the OREA increases exponentially with the number of ions loaded into the trap and with the amplitude of the off-resonance external ac field.

  20. Passivation layers for reduced total dose effects and ELDRS in linear bipolar devices.

    SciTech Connect (OSTI)

    Dodd, Paul Emerson; Riewe, Leonard Charles; Pease, Ronald L.; Shaneyfelt, Marty Ray; Gupta, Sunny; Maher, Michael C.; Schwank, James Ralph

    2003-07-01

    It is shown that final chip passivation layers can have a significant impact on total dose hardness. A number of final chip passivation layers are evaluated to identify films that mitigate enhanced low-dose-rate sensitivity (ELDRS) in National Semiconductor Corporation's linear bipolar technologies. It is shown that devices fabricated with either a low temperature oxide or a tetraethyl ortho silicate passivation do not exhibit significant ELDRS effects up to 100 krad(SiO{sub 2}). Passivation studies on CMOS SRAMs suggest that it is unlikely that the passivation layers (or processing tools) are acting as a new source of hydrogen, which could drift or diffuse into the oxide and increase ELDRS sensitivity. Instead, it is possible that the passivation layers affect the mechanical stress in the oxide, which may affect oxide trap properties and possibly the release and mobility of hydrogen. Correlations between mechanical stress induced by the passivation layers and radiation degradation are discussed.

  1. State of the art in electromagnetic modeling for the Compact Linear Collider

    SciTech Connect (OSTI)

    Candel, Arno; Kabel, Andreas; Lee, Lie-Quan; Li, Zenghai; Ng, Cho; Schussman, Greg; Ko, Kwok; /SLAC

    2009-07-10

    SLAC's Advanced Computations Department (ACD) has developed the parallel 3D electromagnetic time-domain code T3P for simulations of wakefields and transients in complex accelerator structures. T3P is based on state-of-the-art Finite Element methods on unstructured grids and features unconditional stability, quadratic surface approximation and up to 6th-order vector basis functions for unprecedented simulation accuracy. Optimized for large-scale parallel processing on leadership supercomputing facilities, T3P allows simulations of realistic 3D structures with fast turn-around times, aiding the design of the next generation of accelerator facilities. Applications include simulations of the proposed two-beam accelerator structures for the Compact Linear Collider (CLIC) - wakefield damping in the Power Extraction and Transfer Structure (PETS) and power transfer to the main beam accelerating structures are investigated.

  2. Investigation into electron cloud effects in the International Linear Collider positron damping ring

    SciTech Connect (OSTI)

    Crittenden, J.A.; Conway, J.; Dugan, G.F.; Palmer, M.A.; Rubin, D.L.; Shanks, J.; Sonnad, K.G.; Boon, L.; Harkay, K.; Ishibashi, T.; Furman, M.A.; Guiducci, S.; Pivi, M.T.F.; Wang, L.; Crittenden, J.A.; Conway, J.; Dugan, G.F.; Palmer, M.A.; Rubin, D.L.; Shanks, J.; Sonnad, K.G.; Boon, L.; Harkay, K.; Ishibashi, T.; Furman, M.A.; Guiducci, S.; Pivi, M.T.F.; Wang, L.

    2014-02-28

    We report modeling results for electron cloud buildup and instability in the International Linear Collider positron damping ring. Updated optics, wiggler magnets, and vacuum chamber designs have recently been developed for the 5 GeV, 3.2-km racetrack layout. An analysis of the synchrotron radiation profile around the ring has been performed, including the effects of diffuse and specular photon scattering on the interior surfaces of the vacuum chamber. The results provide input to the cloud buildup simulations for the various magnetic field regions of the ring. The modeled cloud densities thus obtained are used in the instability threshold calculations. We conclude that the mitigation techniques employed in this model will suffice to allow operation of the damping ring at the design operational specifications

  3. Electron-ion hybrid instability experiment upgrades to the Auburn Linear Experiment for Instability Studies

    SciTech Connect (OSTI)

    DuBois, A. M.; Arnold, I.; Thomas, E. Jr.; Tejero, E.; Amatucci, W. E.

    2013-04-15

    The Auburn Linear EXperiment for Instability Studies (ALEXIS) is a laboratory plasma physics experiment used to study spatially inhomogeneous flows in a magnetized cylindrical plasma column that are driven by crossed electric (E) and magnetic (B) fields. ALEXIS was recently upgraded to include a small, secondary plasma source for a new dual source, interpenetrating plasma experiment. Using two plasma sources allows for highly localized electric fields to be made at the boundary of the two plasmas, inducing strong E Multiplication-Sign B velocity shear in the plasma, which can give rise to a regime of instabilities that have not previously been studied in ALEXIS. The dual plasma configuration makes it possible to have independent control over the velocity shear and the density gradient. This paper discusses the recent addition of the secondary plasma source to ALEXIS, as well as the plasma diagnostics used to measure electric fields and electron densities.

  4. High resolution, multiple-energy linear sweep detector for x-ray imaging

    DOE Patents [OSTI]

    Perez-Mendez, V.; Goodman, C.A.

    1996-08-20

    Apparatus is disclosed for generating plural electrical signals in a single scan in response to incident X-rays received from an object. Each electrical signal represents an image of the object at a different range of energies of the incident X-rays. The apparatus comprises a first X-ray detector, a second X-ray detector stacked upstream of the first X-ray detector, and an X-ray absorber stacked upstream of the first X-ray detector. The X-ray absorber provides an energy-dependent absorption of the incident X-rays before they are incident at the first X-ray detector, but provides no absorption of the incident X-rays before they are incident at the second X-ray detector. The first X-ray detector includes a linear array of first pixels, each of which produces an electrical output in response to the incident X-rays in a first range of energies. The first X-ray detector also includes a circuit that generates a first electrical signal in response to the electrical output of each of the first pixels. The second X-ray detector includes a linear array of second pixels, each of which produces an electrical output in response to the incident X-rays in a second range of energies, broader than the first range of energies. The second X-ray detector also includes a circuit that generates a second electrical signal in response to the electrical output of each of the second pixels. 12 figs.

  5. High resolution, multiple-energy linear sweep detector for x-ray imaging

    DOE Patents [OSTI]

    Perez-Mendez, Victor (Berkeley, CA); Goodman, Claude A. (Kensington, CA)

    1996-01-01

    Apparatus for generating plural electrical signals in a single scan in response to incident X-rays received from an object. Each electrical signal represents an image of the object at a different range of energies of the incident X-rays. The apparatus comprises a first X-ray detector, a second X-ray detector stacked upstream of the first X-ray detector, and an X-ray absorber stacked upstream of the first X-ray detector. The X-ray absorber provides an energy-dependent absorption of the incident X-rays before they are incident at the first X-ray detector, but provides no absorption of the incident X-rays before they are incident at the second X-ray detector. The first X-ray detector includes a linear array of first pixels, each of which produces an electrical output in response to the incident X-rays in a first range of energies. The first X-ray detector also includes a circuit that generates a first electrical signal in response to the electrical output of each of the first pixels. The second X-ray detector includes a linear array of second pixels, each of which produces an electrical output in response to the incident X-rays in a second range of energies, broader than the first range of energies. The second X-ray detector also includes a circuit that generates a second electrical signal in response to the electrical output of each of the second pixels.

  6. Predicting oropharyngeal tumor volume throughout the course of radiation therapy from pretreatment computed tomography data using general linear models

    SciTech Connect (OSTI)

    Yock, Adam D. Kudchadker, Rajat J.; Rao, Arvind; Dong, Lei; Beadle, Beth M.; Garden, Adam S.; Court, Laurence E.

    2014-05-15

    Purpose: The purpose of this work was to develop and evaluate the accuracy of several predictive models of variation in tumor volume throughout the course of radiation therapy. Methods: Nineteen patients with oropharyngeal cancers were imaged daily with CT-on-rails for image-guided alignment per an institutional protocol. The daily volumes of 35 tumors in these 19 patients were determined and used to generate (1) a linear model in which tumor volume changed at a constant rate, (2) a general linear model that utilized the power fit relationship between the daily and initial tumor volumes, and (3) a functional general linear model that identified and exploited the primary modes of variation between time series describing the changing tumor volumes. Primary and nodal tumor volumes were examined separately. The accuracy of these models in predicting daily tumor volumes were compared with those of static and linear reference models using leave-one-out cross-validation. Results: In predicting the daily volume of primary tumors, the general linear model and the functional general linear model were more accurate than the static reference model by 9.9% (range: ?11.6%23.8%) and 14.6% (range: ?7.3%27.5%), respectively, and were more accurate than the linear reference model by 14.2% (range: ?6.8%40.3%) and 13.1% (range: ?1.5%52.5%), respectively. In predicting the daily volume of nodal tumors, only the 14.4% (range: ?11.1%20.5%) improvement in accuracy of the functional general linear model compared to the static reference model was statistically significant. Conclusions: A general linear model and a functional general linear model trained on data from a small population of patients can predict the primary tumor volume throughout the course of radiation therapy with greater accuracy than standard reference models. These more accurate models may increase the prognostic value of information about the tumor garnered from pretreatment computed tomography images and facilitate improved treatment management.

  7. SU-E-T-52: Beam Data Comparison for 20 Linear Accelerators in One Network

    SciTech Connect (OSTI)

    LoSasso, T; Lim, S; Tang, G; Chan, M; Li, J; Obcemea, C; Song, Y; Ma, R; Yang, G; Xiong, W; Huang, D; Burman, C; Mechalakos, J; Hunt, M

    2014-06-01

    Purpose: To compare photon beam data for the 20 Varian linear accelerators (TrueBeam, iX, and EX models) in use at five centers in the same network with the intent to model with one set of beam data in Eclipsec. Methods: Varian linear accelerators, TrueBeam (3), 21 EX, iX, and Trilogy (14), and 6 EX (3), installed between 1999 and 2014 have their 6 MV and 15 MV x-ray beams reevaluated. Full commissioning, including output factors (St), percent depth doses (PDD), and off-axis profiles, was recently performed for a TrueBeam with a cc04 ion chamber in an IBA Blue phantom. Similarly, a subset of beam data for each of the other accelerators was measured recently as follows: for 33, 1010, and 3030 cm{sup 2} field sizes, flatness and penumbra (8020%) were measured at dmax and 10 cm depths, PDD were measured at 10 and 20 cm depths, and St were measured at 5 cm depth. Measurement results for all machines were compared. Results: For 15 high-energy (6 and 15 MV) and 3 low-energy machines (6MV only): 1) PDD agreed within 1.4% at 10 and 20 cm depths; 2) penumbra agreed within 1.0 mm at dmax and 10 cm depths; 3) flatness was within 1.3% at dmax and 10 cm depths; and 4) with exception of the three low energy machines, output factors were within 1.1% and 0.5% for 33 and 3030 cm{sup 2}, respectively. Measurement uncertainty, not quantified here, accounts for some of these differences. Conclusion: Measured beam data from 15 high-energy Varian linacs are consistent enough that they can be classified using one beam data set in Eclipse. Two additional high-energy machines are removed from this group until their data are further confirmed. Three low-energy machines will be in a separate class based upon differences in output factors (St)

  8. A generating set direct search augmented Lagrangian algorithm for optimization with a combination of general and linear constraints.

    SciTech Connect (OSTI)

    Lewis, Robert Michael (College of William and Mary, Williamsburg, VA); Torczon, Virginia Joanne (College of William and Mary, Williamsburg, VA); Kolda, Tamara Gibson

    2006-08-01

    We consider the solution of nonlinear programs in the case where derivatives of the objective function and nonlinear constraints are unavailable. To solve such problems, we propose an adaptation of a method due to Conn, Gould, Sartenaer, and Toint that proceeds by approximately minimizing a succession of linearly constrained augmented Lagrangians. Our modification is to use a derivative-free generating set direct search algorithm to solve the linearly constrained subproblems. The stopping criterion proposed by Conn, Gould, Sartenaer and Toint for the approximate solution of the subproblems requires explicit knowledge of derivatives. Such information is presumed absent in the generating set search method we employ. Instead, we show that stationarity results for linearly constrained generating set search methods provide a derivative-free stopping criterion, based on a step-length control parameter, that is sufficient to preserve the convergence properties of the original augmented Lagrangian algorithm.

  9. Linear stability and nonlinear dynamics of the fishbone mode in spherical tokamaks

    SciTech Connect (OSTI)

    Wang, Feng; Liu, J. Y. [School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Fu, G. Y.; Breslau, J. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2013-10-15

    Extensive linear and nonlinear simulations have been carried out to investigate the energetic particle-driven fishbone instability in spherical tokamak plasmas with weakly reversed q profile and the q{sub min} slightly above unity. The global kinetic-MHD hybrid code M3D-K is used. Numerical results show that a fishbone instability is excited by energetic beam ions preferentially at higher q{sub min} values, consistent with the observed appearance of the fishbone before the long-lived mode in MAST and NSTX experiments. In contrast, at lower q{sub min} values, the fishbone tends to be stable. In this case, the beam ion effects are strongly stabilizing for the non-resonant kink mode. Nonlinear simulations show that the fishbone saturates with strong downward frequency chirping as well as radial flattening of the beam ion distribution. An (m, n) = (2, 1) magnetic island is found to be driven nonlinearly by the fishbone instability, which could provide a trigger for the (2, 1) neoclassical tearing mode sometimes observed after the fishbone instability in NSTX.

  10. Object detection utilizing a linear retrieval algorithm for thermal infrared imagery

    SciTech Connect (OSTI)

    Ramsey, M.S. [Arizona State Univ., Tempe, AZ (United States)

    1996-11-01

    Thermal infrared (TIR) spectroscopy and remote sensing have been proven to be extremely valuable tools for mineralogic discrimination. One technique for sub-pixel detection and data reduction, known as a spectral retrieval or unmixing algorithm, will prove useful in the analysis of data from scheduled TIR orbital instruments. This study represents the first quantitative attempt to identify the limits of the model, specifically concentrating on the TIR. The algorithm was written and applied to laboratory data, testing the effects of particle size, noise, and multiple endmembers, then adapted to operate on airborne Thermal Infrared Multispectral Scanner data of the Kelso Dunes, CA, Meteor Crater, AZ, and Medicine Lake Volcano, CA. Results indicate that linear spectral unmixmg can produce accurate endmember detection to within an average of 5%. In addition, the effects of vitrification and textural variations were modeled. The ability to predict mineral or rock abundances becomes extremely useful in tracking sediment transport, decertification, and potential hazard assessment in remote volcanic regions. 26 refs., 3 figs.

  11. A new method for RF power generation for two-beam linear colliders

    SciTech Connect (OSTI)

    Braun, H.; Corsini, R.; D'Amico, T.; Delahaye, J. P.; Guignard, G.; Johnson, C.; Millich, A.; Pearce, P.; Rinolfi, L.; Riche, A.; Schulte, D.; Thorndahl, L.; Valentini, M.; Wilson, I.; Ruth, R. D. [CERN, Geneva (Switzerland); Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)

    1999-05-07

    In this paper we discuss a new approach to two-beam acceleration. The energy for RF production is initially stored in a long-pulse electron beam which is efficiently accelerated to about 1.2 GeV by a fully loaded, conventional, low frequency ({approx}1 GHz) linac. The beam pulse length is twice the length of the high-gradient linac. Segments of this long pulse beam are compressed using combiner rings to create a sequence of higher peak power drive beams with gaps in between. This train of drive beams is distributed from the end of the linac against the main beam direction down a common transport line so that each drive beam can power a section of the main linac. After a 180-degree turn, each high-current, low-energy drive beam is decelerated in low-impedance decelerator structures, and the resulting power is used to accelerate the low-current, high-energy beam in the main linac. The method discussed here seems relatively inexpensive, is very flexible and can be used to accelerate beams for linear colliders over the entire frequency and energy range.

  12. A new method for RF power generation for two-beam linear colliders

    SciTech Connect (OSTI)

    Braun, H.; Corsini, R.; DAmico, T.; Delahaye, J.P.; Guignard, G.; Johnson, C.; Millich, A.; Pearce, P.; Rinolfi, L.; Riche, A.; Schulte, D.; Thorndahl, L.; Valentini, M.; Wilson, I. [CERN, Geneva (Switzerland); Ruth, R.D. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States)

    1999-05-01

    In this paper we discuss a new approach to two-beam acceleration. The energy for RF production is initially stored in a long-pulse electron beam which is efficiently accelerated to about 1.2 GeV by a fully loaded, conventional, low frequency ({approximately}1 GHz) linac. The beam pulse length is twice the length of the high-gradient linac. Segments of this long pulse beam are compressed using combiner rings to create a sequence of higher peak power drive beams with gaps in between. This train of drive beams is distributed from the end of the linac against the main beam direction down a common transport line so that each drive beam can power a section of the main linac. After a 180-degree turn, each high-current, low-energy drive beam is decelerated in low-impedance decelerator structures, and the resulting power is used to accelerate the low-current, high-energy beam in the main linac. The method discussed here seems relatively inexpensive, is very flexible and can be used to accelerate beams for linear colliders over the entire frequency and energy range. {copyright} {ital 1999 American Institute of Physics.}

  13. The linearly scaling 3D fragment method for large scale electronic structure calculations

    SciTech Connect (OSTI)

    Zhao, Zhengji; Meza, Juan; Lee, Byounghak; Shan, Hongzhang; Strohmaier, Erich; Bailey, David; Wang, Lin-Wang

    2009-07-28

    The Linearly Scaling three-dimensional fragment (LS3DF) method is an O(N) ab initio electronic structure method for large-scale nano material simulations. It is a divide-and-conquer approach with a novel patching scheme that effectively cancels out the artificial boundary effects, which exist in all divide-and-conquer schemes. This method has made ab initio simulations of thousand-atom nanosystems feasible in a couple of hours, while retaining essentially the same accuracy as the direct calculation methods. The LS3DF method won the 2008 ACM Gordon Bell Prize for algorithm innovation. Our code has reached 442 Tflop/s running on 147,456 processors on the Cray XT5 (Jaguar) at OLCF, and has been run on 163,840 processors on the Blue Gene/P (Intrepid) at ALCF, and has been applied to a system containing 36,000 atoms. In this paper, we will present the recent parallel performance results of this code, and will apply the method to asymmetric CdSe/CdS core/shell nanorods, which have potential applications in electronic devices and solar cells.

  14. The Linearly Scaling 3D Fragment Method for Large Scale Electronic Structure Calculations

    SciTech Connect (OSTI)

    Zhao, Zhengji; Meza, Juan; Lee, Byounghak; Shan, Hongzhang; Strohmaier, Erich; Bailey, David; Wang, Lin-Wang

    2009-06-26

    The Linearly Scaling three-dimensional fragment (LS3DF) method is an O(N) ab initio electronic structure method for large-scale nano material simulations. It is a divide-and-conquer approach with a novel patching scheme that effectively cancels out the artificial boundary effects, which exist in all divide-and-conquer schemes. This method has made ab initio simulations of thousand-atom nanosystems feasible in a couple of hours, while retaining essentially the same accuracy as the direct calculation methods. The LS3DF method won the 2008 ACM Gordon Bell Prize for algorithm innovation. Our code has reached 442 Tflop/s running on 147,456 processors on the Cray XT5 (Jaguar) at OLCF, and has been run on 163,840 processors on the Blue Gene/P (Intrepid) at ALCF, and has been applied to a system containing 36,000 atoms. In this paper, we will present the recent parallel performance results of this code, and will apply the method to asymmetric CdSe/CdS core/shell nanorods, which have potential applications in electronic devices and solar cells.

  15. Linearly Organized Turbulence Structures Observed Over a Suburban Area by Dual-Doppler Lidar

    SciTech Connect (OSTI)

    Newsom, Rob K.; Calhoun, Ron; Ligon, David; Allwine, K Jerry

    2008-04-01

    Dual-Doppler lidar observations are used to investigate the structure and evolution of surface layer flow over a suburban area. The observations were made during the Joint Urban 2003 (JU2003) field experiment in Oklahoma City in the summer of 2003. This study focuses specifically on a 10-hour sequence of scan data beginning shortly after noon local time on July 7, 2003. During this period two coherent Doppler lidars performed overlapping low elevation angle sector scans upwind and south of Oklahoma Citys central business district (CBD). Radial velocity data from the two lidars are processed to reveal the structure and evolution of the horizontal velocity field in the surface layer throughout the afternoon and evening transition periods. The retrieved velocity fields clearly show a tendency for turbulence structures to be elongated in the direction of the mean flow throughout the entire 10-hour study period. As the stratification changed from unstable to weakly stable the turbulence structures became increasingly more linearly organized, and the cross-stream separation between high- and low-speed regoins decreased. The spatially resolved velocity fields are used to estimate streamwise and cross-stream turbulence length scales as functions of stability.

  16. Calculation of excitation energies from the CC2 linear response theory using Cholesky decomposition

    SciTech Connect (OSTI)

    Baudin, Pablo; qLEAP Center for Theoretical Chemistry, Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C ; Marn, Jos Snchez; Cuesta, Inmaculada Garca; Snchez de Mers, Alfredo M. J.

    2014-03-14

    A new implementation of the approximate coupled cluster singles and doubles CC2 linear response model is reported. It employs a Cholesky decomposition of the two-electron integrals that significantly reduces the computational cost and the storage requirements of the method compared to standard implementations. Our algorithm also exploits a partitioning form of the CC2 equations which reduces the dimension of the problem and avoids the storage of doubles amplitudes. We present calculation of excitation energies of benzene using a hierarchy of basis sets and compare the results with conventional CC2 calculations. The reduction of the scaling is evaluated as well as the effect of the Cholesky decomposition parameter on the quality of the results. The new algorithm is used to perform an extrapolation to complete basis set investigation on the spectroscopically interesting benzylallene conformers. A set of calculations on medium-sized molecules is carried out to check the dependence of the accuracy of the results on the decomposition thresholds. Moreover, CC2 singlet excitation energies of the free base porphin are also presented.

  17. Effect of Fractionation in Stereotactic Body Radiation Therapy Using the Linear Quadratic Model

    SciTech Connect (OSTI)

    Yang, Jun; Philadelphia Cyberknife, Havertown, Pennsylvania ; Lamond, John; Philadelphia Cyberknife, Havertown, Pennsylvania ; Fowler, Jack; Lanciano, Rachelle; Philadelphia Cyberknife, Havertown, Pennsylvania ; Feng, Jing; Brady, Luther; Philadelphia Cyberknife, Havertown, Pennsylvania

    2013-05-01

    Purpose: To examine the fractionation effect of stereotactic body radiation therapy with a heterogeneous dose distribution. Methods: Derived from the linear quadratic formula with measurements from a hypothetical 2-cm radiosurgical tumor, the threshold percentage was defined as (?/?{sub tissue}/?/?{sub tumor}), the balance ?/? ratio was defined as (prescription dose/tissue tolerance*?/?{sub tumor}), and the balance dose was defined as (tissue tolerance/threshold percentage). Results: With increasing fractions and equivalent peripheral dose to the target, the biological equivalent dose of hot spots in a target decreases. The relative biological equivalent doses of serial organs decrease only when the relative percentage of its dose to the prescription dose is above the threshold percentage. The volume of parallel organs at risk decreases only when the tumor's ?/? ratio is above the balance ?/? ratio and the prescription dose is lower than balance dose. Conclusions: The potential benefits of fractionation in stereotactic body radiation therapy depend on the complex interplay between the total dose, ?/? ratios, and dose differences between the target and the surrounding normal tissues.

  18. A flexible uncertainty quantification method for linearly coupled multi-physics systems

    SciTech Connect (OSTI)

    Chen, Xiao Ng, Brenda; Sun, Yunwei; Tong, Charles

    2013-09-01

    Highlights: We propose a modularly hybrid UQ methodology suitable for independent development of module-based multi-physics simulation. Our algorithmic framework allows for each module to have its own UQ method (either intrusive or non-intrusive). Information from each module is combined systematically to propagate global uncertainty. Our proposed approach can allow for easy swapping of new methods for any modules without the need to address incompatibilities. We demonstrate the proposed framework on a practical application involving a multi-species reactive transport model. -- Abstract: This paper presents a novel approach to building an integrated uncertainty quantification (UQ) methodology suitable for modern-day component-based approach for multi-physics simulation development. Our hybrid UQ methodology supports independent development of the most suitable UQ method, intrusive or non-intrusive, for each physics module by providing an algorithmic framework to couple these stochastic modules for propagating global uncertainties. We address algorithmic and computational issues associated with the construction of this hybrid framework. We demonstrate the utility of such a framework on a practical application involving a linearly coupled multi-species reactive transport model.

  19. Consequences of bounds on longitudinal emittance growth for the design of recirculating linear accelerators

    SciTech Connect (OSTI)

    Berg, J. S.

    2015-05-03

    Recirculating linear accelerators (RLAs) are a cost-effective method for the acceleration of muons for a muon collider in energy ranges from a couple GeV to a few 10s of GeV. Muon beams generally have longitudinal emittances that are large for the RF frequency that is used, and it is important to limit the growth of that longitudinal emittance. This has particular consequences for the arc design of the RLAs. I estimate the longitudinal emittance growth in an RLA arising from the RF nonlinearity. Given an emittance growth limitation and other design parameters, one can then compute the maximum momentum compaction in the arcs. I describe how to obtain an approximate arc design satisfying these requirements based on the deisgn in [1]. Longitudinal dynamics also determine the energy spread in the beam, and this has consequences on the transverse phase advance in the linac. This in turn has consequences for the arc design due to the need to match beta functions. I combine these considerations to discuss design parameters for the acceleration of muons for a collider in an RLA from 5 to 63 GeV.

  20. Time Reversal in Solids (Linear and Nonlinear Elasticity): Multimedia Resources in Time Reversal

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Dynamic nonlinear elastic behavior, nonequilibrium dynamics, first observed as a curiosity in earth materials has now been observed in a great variety of solids. The primary manifestations of the behavior are characteristic wave distortion, and slow dynamics, a recovery process to equilibrium that takes place linearly with the logarithm of time, over hours to days after a wave disturbance. The link between the diverse materials that exhibit nonequilibrium dynamics appears to be the presence of soft regions, thought to be 'damage' at many scales, ranging from order 10-9 m to 10-1 m at least. The regions of soft matter may be distributed as in a rock sample, or isolated, as in a sample with a single crack [LANLhttp://www.lanl.gov/orgs/ees/ees11/geophysics/nonlinear/nonlinear.shtml]. The Geophysics Group (EES-11) at Los Alamos National Laboratory has posted two or more multimedia items under each of the titles below to demonstrate aspects of their work: 1) Source Reconstruction Using Time Reversal; 2) Robustness and Efficiency of Time Reversal Acoustics in Solid Media; 3) Audio Example of Time Reversal - Speech Privacy; 4) Crack Imagining with Time Reversal - Experimental Results; 5) Time Reversal of the 2004 (M9.0) Sumatra Earthquake.

  1. A linear radio frequency plasma reactor for potential and current mapping in a magnetized plasma

    SciTech Connect (OSTI)

    Faudot, E.; Devaux, S.; Moritz, J.; Heuraux, S.; Molina Cabrera, P.; Brochard, F.

    2015-06-15

    Langmuir probe measurements in front of high power ion cyclotron resonant frequency antennas are not possible or simply too noisy to be analyzed properly. A linear experiment is a radio frequency (RF) magnetized plasma discharge reactor designed to probe the rectified potential in front of such antennas but at low power level (1 kW) to next improve antenna design and mitigate sheath effects. The maximum magnetic field is 0.1 T, and the RF amplifier can work between 10 kHz and 250 MHz allowing ion cyclotron resonances for argon or helium. The first measurements with no magnetic field are presented here, especially 2D potential maps extracted from the RF compensated probe measurements yield ni ≈ 10{sup 15} m{sup −3} and Te ≈ 2 eV for RF power lower than 100 W. Series resonances in the chamber are highlighted and allow to deduce the plasma parameters from a simple equivalent impedance model of the plasma in helium gas. Next studies will be focused on magnetized plasmas and especially magnetized RF sheaths.

  2. Ion species control in high flux deuterium plasma beams produced by a linear plasma generator

    SciTech Connect (OSTI)

    Luo, G.-N.; Shu, W.M.; Nakamura, H.; O'Hira, S.; Nishi, M.

    2004-11-01

    The ion species ratios in low energy high flux deuterium plasma beams formed in a linear plasma generator were measured by a quadrupole mass spectrometer. And the species control in the plasma generator was evaluated by changing the operational parameters like neutral pressure, arc current, and axial magnetic confinement to the plasma column. The measurements reveal that the lower pressures prefer to form more D{sup +} ions, and the medium magnetic confinement at the higher pressures results in production of more D{sub 2}{sup +}, while the stronger confinement and/or larger arc current are helpful to D{sub 2}{sup +} conversion into D{sub 3}{sup +}. Therefore, the ion species can be controlled by adjusting the operational parameters of the plasma generator. With suitable adjustment, we can achieve plasma beams highly enriched with a single species of D{sup +}, D{sub 2}{sup +}, or D{sub 3}{sup +}, to a ratio over 80%. It has been found that the axial magnetic configuration played a significant role in the formation of D{sub 3}{sup +} within the experimental pressure range.

  3. Unified Einstein-Virasoro Master Equation in the General Non-Linear Sigma Model

    SciTech Connect (OSTI)

    Boer, J. de; Halpern, M.B.

    1996-06-05

    The Virasoro master equation (VME) describes the general affine-Virasoro construction $T=L^abJ_aJ_b+iD^a \\dif J_a$ in the operator algebra of the WZW model, where $L^ab$ is the inverse inertia tensor and $D^a $ is the improvement vector. In this paper, we generalize this construction to find the general (one-loop) Virasoro construction in the operator algebra of the general non-linear sigma model. The result is a unified Einstein-Virasoro master equation which couples the spacetime spin-two field $L^ab$ to the background fields of the sigma model. For a particular solution $L_G^ab$, the unified system reduces to the canonical stress tensors and conventional Einstein equations of the sigma model, and the system reduces to the general affine-Virasoro construction and the VME when the sigma model is taken to be the WZW action. More generally, the unified system describes a space of conformal field theories which is presumably much larger than the sum of the general affine-Virasoro construction and the sigma model with its canonical stress tensors. We also discuss a number of algebraic and geometrical properties of the system, including its relation to an unsolved problem in the theory of $G$-structures on manifolds with torsion.

  4. Direct-Steam Linear Fresnel Performance Model for NREL's System Advisor Model

    SciTech Connect (OSTI)

    Wagner, M. J.; Zhu, G.

    2012-09-01

    This paper presents the technical formulation and demonstrated model performance results of a new direct-steam-generation (DSG) model in NREL's System Advisor Model (SAM). The model predicts the annual electricity production of a wide range of system configurations within the DSG Linear Fresnel technology by modeling hourly performance of the plant in detail. The quasi-steady-state formulation allows users to investigate energy and mass flows, operating temperatures, and pressure drops for geometries and solar field configurations of interest. The model includes tools for heat loss calculation using either empirical polynomial heat loss curves as a function of steam temperature, ambient temperature, and wind velocity, or a detailed evacuated tube receiver heat loss model. Thermal losses are evaluated using a computationally efficient nodal approach, where the solar field and headers are discretized into multiple nodes where heat losses, thermal inertia, steam conditions (including pressure, temperature, enthalpy, etc.) are individually evaluated during each time step of the simulation. This paper discusses the mathematical formulation for the solar field model and describes how the solar field is integrated with the other subsystem models, including the power cycle and optional auxiliary fossil system. Model results are also presented to demonstrate plant behavior in the various operating modes.

  5. On the Bayesian Treed Multivariate Gaussian Process with Linear Model of Coregionalization

    SciTech Connect (OSTI)

    Konomi, Bledar A.; Karagiannis, Georgios; Lin, Guang

    2015-02-01

    The Bayesian treed Gaussian process (BTGP) has gained popularity in recent years because it provides a straightforward mechanism for modeling non-stationary data and can alleviate computational demands by fitting models to less data. The extension of BTGP to the multivariate setting requires us to model the cross-covariance and to propose efficient algorithms that can deal with trans-dimensional MCMC moves. In this paper we extend the cross-covariance of the Bayesian treed multivariate Gaussian process (BTMGP) to that of linear model of Coregionalization (LMC) cross-covariances. Different strategies have been developed to improve the MCMC mixing and invert smaller matrices in the Bayesian inference. Moreover, we compare the proposed BTMGP with existing multiple BTGP and BTMGP in test cases and multiphase flow computer experiment in a full scale regenerator of a carbon capture unit. The use of the BTMGP with LMC cross-covariance helped to predict the computer experiments relatively better than existing competitors. The proposed model has a wide variety of applications, such as computer experiments and environmental data. In the case of computer experiments we also develop an adaptive sampling strategy for the BTMGP with LMC cross-covariance function.

  6. Field Testing of Linear Individual Pitch Control on the Two-Bladed Controls Advanced Research Turbine

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    van Solingen, Edwin; Fleming, Paul A.; Scholbrock, Andrew; van Wingerden, Jan-Willem

    2016-03-01

    This paper presents the results of field tests using linear individual pitch control (LIPC) on the two-bladed Controls Advanced Research Turbine 2 (CART2) at the National Renewable Energy Laboratory (NREL). LIPC has recently been introduced as an alternative to the conventional individual pitch control (IPC) strategy for two-bladed wind turbines. The main advantage of LIPC over conventional IPC is that it requires, at most, only two feedback loops to potentially reduce the periodic blade loads. In previous work, LIPC was designed to implement blade pitch angles at a fixed frequency (e.g., the once-per-revolution (1P) frequency), which made it only applicablemore » in above-rated wind turbine operating conditions. In this study, LIPC is extended to below-rated operating conditions by gain scheduling the controller on the rotor speed. With this extension, LIPC and conventional IPC are successfully applied to the NREL CART2 wind turbine. The field-test results obtained during the measurement campaign indicate that LIPC significantly reduces the wind turbine loads for both below-rated and above-rated operation.« less

  7. Study of Ion Cooling and Ejection from Two Stage Linear Quadrupole Ion Trap consisted of RFQ ion guides

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ion Cooling and Ejection from Two Stage Linear Quadrupole Ion Trap consisted of RFQ ion guides Kozlovskiy V.I., Filatov V. V., Shchepunov (UNIRIB, O.R.A.U. Oak Ridge, TN, USA) V. A., Brusov V. S., Pikhtelev A. R., Zelenov V. V. Introduction The primary objective of this work concerns linear quadrupole ion traps, which are commonly used to interface a continuous ion beam from an external source with a mass analyzer, requiring bunched or pulsed beams. We assume that the ions prepared for mass

  8. Simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    SciTech Connect (OSTI)

    Yang, Xi; Huang, Xiaobiao

    2015-11-10

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. Furthermore, the fitting results are used for lattice correction. Our method has been successfully demonstrated on the NSLS-II storage ring.

  9. Dose calculation for permanent prostate implants incorporating spatially anisotropic linearly time-resolving edema

    SciTech Connect (OSTI)

    Monajemi, T. T.; Clements, Charles M.; Sloboda, Ron S.

    2011-04-15

    Purpose: The objectives of this study were (i) to develop a dose calculation method for permanent prostate implants that incorporates a clinically motivated model for edema and (ii) to illustrate the use of the method by calculating the preimplant dosimetry error for a reference configuration of {sup 125}I, {sup 103}Pd, and {sup 137}Cs seeds subject to edema-induced motions corresponding to a variety of model parameters. Methods: A model for spatially anisotropic edema that resolves linearly with time was developed based on serial magnetic resonance imaging measurements made previously at our center to characterize the edema for a group of n=40 prostate implant patients [R. S. Sloboda et al., ''Time course of prostatic edema post permanent seed implant determined by magnetic resonance imaging,'' Brachytherapy 9, 354-361 (2010)]. Model parameters consisted of edema magnitude, {Delta}, and period, T. The TG-43 dose calculation formalism for a point source was extended to incorporate the edema model, thus enabling calculation via numerical integration of the cumulative dose around an individual seed in the presence of edema. Using an even power piecewise-continuous polynomial representation for the radial dose function, the cumulative dose was also expressed in closed analytical form. Application of the method was illustrated by calculating the preimplant dosimetry error, RE{sub preplan}, in a 5x5x5 cm{sup 3} volume for {sup 125}I (Oncura 6711), {sup 103}Pd (Theragenics 200), and {sup 131}Cs (IsoRay CS-1) seeds arranged in the Radiological Physics Center test case 2 configuration for a range of edema relative magnitudes ({Delta}=[0.1,0.2,0.4,0.6,1.0]) and periods (T=[28,56,84] d). Results were compared to preimplant dosimetry errors calculated using a variation of the isotropic edema model developed by Chen et al. [''Dosimetric effects of edema in permanent prostate seed implants: A rigorous solution,'' Int. J. Radiat. Oncol., Biol., Phys. 47, 1405-1419 (2000)]. Results: As expected, RE{sub preplan} for our edema model indicated underdosage in the calculation volume with a clear dependence on seed and calculation point positions, and increased with increasing values of {Delta} and T. Values of RE{sub preplan} were generally larger near the ends of the virtual prostate in the RPC phantom compared with more central locations. For edema characteristics similar to the population average values previously measured at our center, i.e., {Delta}=0.2 and T=28 d, mean values of RE{sub preplan} in an axial plane located 1.5 cm from the center of the seed distribution were 8.3% for {sup 131}Cs seeds, 7.5% for {sup 103}Pd seeds, and 2.2% for {sup 125}I seeds. Maximum values of RE{sub preplan} in the same plane were about 1.5 times greater. Note that detailed results strictly apply only for loose seed implants where the seeds are fixed in tissue and move in synchrony with that tissue. Conclusions: A dose calculation method for permanent prostate implants incorporating spatially anisotropic linearly time-resolving edema was developed for which cumulative dose can be written in closed form. The method yields values for RE{sub preplan} that differ from those for spatially isotropic edema. The method is suitable for calculating pre- and postimplant dosimetry correction factors for clinical seed configurations when edema characteristics can be measured or estimated.

  10. PHYSICAL PROPERTIES OF MAIN-BELT COMET 176P/LINEAR

    SciTech Connect (OSTI)

    Hsieh, Henry H.; Ishiguro, Masateru; Lacerda, Pedro; Jewitt, David E-mail: p.lacerda@qub.ac.uk E-mail: jewitt@ucla.edu

    2011-07-15

    We present a physical characterization of comet 176P/LINEAR, the third discovered member of the new class of main-belt comets, which exhibit cometary activity but are dynamically indistinguishable from main-belt asteroids. Observations show the object exhibiting a fan-shaped tail for at least one month in late 2005, but then becoming inactive in early 2006. During this active period, we measure broadband colors of B - V = 0.63 {+-} 0.02, V - R = 0.35 {+-} 0.02, and R - I = 0.31 {+-} 0.04. Using data from when the object was observed to be inactive, we derive best-fit IAU phase function parameters of H = 15.10 {+-} 0.05 mag and G = 0.15 {+-} 0.10, and best-fit linear phase function parameters of m(1, 1, 0) = 15.35 {+-} 0.05 mag and {beta} = 0.038 {+-} 0.005 mag deg{sup -1}. From this baseline phase function, we find that 176P exhibits a mean photometric excess of {approx}30% during its active period, implying an approximate total coma dust mass of M{sub d} {approx} (7.2 {+-} 3.6) x 10{sup 4} kg. From inactive data obtained in early 2007, we find a rotation period of P{sub rot} = 22.23 {+-} 0.01 hr and a peak-to-trough photometric range of {Delta}m {approx} 0.7 mag. Phasing our photometric data from 176P's 2005 active period to this rotation period, we find that the nucleus exhibits a significantly smaller photometric range than in 2007 that cannot be accounted for by coma damping effects, and as such, are attributed by us to viewing geometry effects. A detailed analysis of these geometric effects showed that 176P is likely to be a highly elongated object with an axis ratio of 1.8 < b/a < 2.1, an orbital obliquity of {epsilon} {approx} 60{sup 0}, and a solstice position at a true anomaly of {nu}{sub o} = 20{sup 0} {+-} 20{sup 0}. Numerical modeling of 176P's dust emission found that its activity can only be reproduced by asymmetric dust emission, such as a cometary jet. We find plausible fits to our observations using models assuming {approx}10 {mu}m dust particles continuously emitted over the period during which 176P was observed to be active, and a jet direction of 180{sup 0} {approx}< {alpha}{sub jet} {approx}< 120{sup 0} and {delta}{sub jet} {approx} -60{sup 0}. We do not find good fits to our observations using models of impulsive dust emission, i.e., what would be expected if 176P's activity was an ejecta cloud resulting from an impact into non-volatile asteroid regolith. Since for a rotating body, the time-averaged direction of a non-equatorial jet is equivalent to the direction of the nearest rotation pole, we find an equivalent orbital obliquity of 50{sup 0} {approx}< {epsilon} {approx}< 75{sup 0}, consistent with the results of our light curve analysis. Furthermore, the results of both our light curve analysis and dust modeling analysis are consistent with the seasonal heating hypothesis used to explain the modulation of 176P's activity. Additional observations are highly encouraged to further characterize 176P's active behavior as the object approaches perihelion on 2011 July 1.

  11. DENSITY WAVES EXCITED BY LOW-MASS PLANETS IN PROTOPLANETARY DISKS. I. LINEAR REGIME

    SciTech Connect (OSTI)

    Dong, Ruobing; Stone, James M.; Petrovich, Cristobal; Rafikov, Roman R. E-mail: rrr@astro.princeton.edu E-mail: cpetrovi@astro.princeton.edu

    2011-11-01

    Density waves excited by planets embedded in protoplanetary disks play a central role in planetary migration and gap opening processes. We carry out two-dimensional shearing sheet simulations to study the linear regime of wave evolution with the grid-based code Athena and provide detailed comparisons with theoretical predictions. Low-mass planets (down to {approx}0.03 M{sub Circled-Plus} at 1 AU) and high spatial resolution (256 grid points per scale height) are chosen to mitigate the effects of wave nonlinearity. To complement the existing numerical studies, we focus on the primary physical variables such as the spatial profile of the wave, torque density, and the angular momentum flux carried by the wave, instead of secondary quantities such as the planetary migration rate. Our results show percent level agreement with theory in both physical and Fourier spaces. New phenomena such as the change of the toque density sign far from the planet are discovered and discussed. Also, we explore the effect of the numerical algorithms and find that a high order of accuracy, high resolution, and an accurate planetary potential are crucial to achieve good agreement with the theory. We find that the use of a too large time step without properly resolving the dynamical timescale around the planet produces incorrect results and may lead to spurious gap opening. Global simulations of planet migration and gap opening violating this requirement may be affected by spurious effects resulting in, e.g., the incorrect planetary migration rate and gap opening mass.

  12. Competitive lithium solvation of linear and cyclic carbonates from quantum chemistry

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kent, Paul R. C.; Ganesh, Panchapakesan; Borodin, Oleg; Olguin, Marco; Allen, Joshua L.; Henderson, Wesley A.

    2015-11-17

    The composition of the lithium cation (Li+) solvation shell in mixed linear and cyclic carbonate-based electrolytes has been re-examined using Born–Oppenheimer molecular dynamics (BOMD) as a function of salt concentration and cluster calculations with ethylene carbonate:dimethyl carbonate (EC:DMC)–LiPF6 as a model system. A coordination preference for EC over DMC to a Li+ was found at low salt concentrations, while a slightly higher preference for DMC over EC was found at high salt concentrations. Analysis of the relative binding energies of the (EC)n(DMC)m–Li+ and (EC)n(DMC)m–LiPF6 solvates in the gas-phase and for an implicit solvent (as a function of the solvent dielectricmore » constant) indicated that the DMC-containing Li+ solvates were stabilized relative to (EC4)–Li+ and (EC)3–LiPF6 by immersing them in the implicit solvent. Such stabilization was more pronounced in the implicit solvents with a high dielectric constant. Results from previous Raman and IR experiments were reanalyzed and reconciled by correcting them for changes of the Raman activities, IR intensities and band shifts for the solvents which occur upon Li+ coordination. After these correction factors were applied to the results of BOMD simulations, the composition of the Li+ solvation shell from the BOMD simulations was found to agree well with the solvation numbers extracted from Raman experiments. Finally, the mechanism of the Li+ diffusion in the dilute (EC:DMC)LiPF6 mixed solvent electrolyte was studied using the BOMD simulations.« less

  13. The Component Slope Linear Model for Calculating Intensive Partial Molar Properties: Application to Waste Glasses

    SciTech Connect (OSTI)

    Reynolds, Jacob G.

    2013-01-11

    Partial molar properties are the changes occurring when the fraction of one component is varied while the fractions of all other component mole fractions change proportionally. They have many practical and theoretical applications in chemical thermodynamics. Partial molar properties of chemical mixtures are difficult to measure because the component mole fractions must sum to one, so a change in fraction of one component must be offset with a change in one or more other components. Given that more than one component fraction is changing at a time, it is difficult to assign a change in measured response to a change in a single component. In this study, the Component Slope Linear Model (CSLM), a model previously published in the statistics literature, is shown to have coefficients that correspond to the intensive partial molar properties. If a measured property is plotted against the mole fraction of a component while keeping the proportions of all other components constant, the slope at any given point on a graph of this curve is the partial molar property for that constituent. Actually plotting this graph has been used to determine partial molar properties for many years. The CSLM directly includes this slope in a model that predicts properties as a function of the component mole fractions. This model is demonstrated by applying it to the constant pressure heat capacity data from the NaOH-NaAl(OH{sub 4}H{sub 2}O system, a system that simplifies Hanford nuclear waste. The partial molar properties of H{sub 2}O, NaOH, and NaAl(OH){sub 4} are determined. The equivalence of the CSLM and the graphical method is verified by comparing results detennined by the two methods. The CSLM model has been previously used to predict the liquidus temperature of spinel crystals precipitated from Hanford waste glass. Those model coefficients are re-interpreted here as the partial molar spinel liquidus temperature of the glass components.

  14. Interim report on the Global Design Effort Global International Linear Collider (ILC) R&D

    SciTech Connect (OSTI)

    Harrison, M.

    2011-04-30

    The International Linear Collider: A Technical Progress Report marks the halfway point towards the Global Design Effort fulfilling its mandate to follow up the ILC Reference Design Report with a more optimised Technical Design Report (TDR) by the end of 2012. The TDR will be based on much of the work reported here and will contain all the elements needed to propose the ILC to collaborating governments, including a technical design and implementation plan that are realistic and have been better optimised for performance, cost and risk. We are on track to develop detailed plans for the ILC, such that once results from the Large Hadron Collider (LHC) at CERN establish the main science goals and parameters of the next machine, we will be in good position to make a strong proposal for this new major global project in particle physics. The two overriding issues for the ILC R&D programme are to demonstrate that the technical requirements for the accelerator are achievable with practical technologies, and that the ambitious physics goals can be addressed by realistic ILC detectors. This GDE interim report documents the impressive progress on the accelerator technologies that can make the ILC a reality. It highlights results of the technological demonstrations that are giving the community increased confidence that we will be ready to proceed with an ILC project following the TDR. The companion detector and physics report document likewise demonstrates how detector designs can meet the ambitious and detailed physics goals set out by the ILC Steering Committee. LHC results will likely affect the requirements for the machine design and the detectors, and we are monitoring that very closely, intending to adapt our design as those results become available.

  15. Preliminary Safety Analysis Report (PSAR), The NSLS 200 MeV Linear Electron Accelerator

    SciTech Connect (OSTI)

    Blumberg, L.N.; Ackerman, A.I.; Dickinson, T.; Heese, R.N.; Larson, R.A.; Neuls, C.W.; Pjerov, S.; Sheehan, J.F.

    1993-06-15

    The radiological, fire and electrical hazards posed by a 200 MeV electron Linear Accelerator, which the NSLS Department will install and commission within a newly assembled structure, are addressed in this Preliminary Safety Analysis Report. Although it is clear that this accelerator is intended to be the injector for a future experimental facility, we address only the Linac in the present PSAR since neither the final design nor the operating characteristics of the experimental facility are known at the present time. The fire detection and control system to be installed in the building is judged to be completely adequate in terms of the marginal hazard presented - no combustible materials other than the usual cabling associated with such a facility have been identified. Likewise, electrical hazards associated with power supplies for the beam transport magnets and accelerator components such as the accelerator klystrons and electron gun are classified as marginal in terms of potential personnel injury, cost of equipment lost, program downtime and public impact perceptions as defined in the BNL Environmental Safety and Health Manual and the probability of occurrence is deemed to be remote. No unusual features have been identified for the power supplies or electrical distribution system, and normal and customary electrical safety standards as practiced throughout the NSLS complex and the Laboratory are specified in this report. The radiation safety hazards are similarly judged to be marginal in terms of probability of occurrence and potential injury consequences since, for the low intensity operation proposed - a factor of 25 less than the maximum Linac capability specified by the vendor - the average beam power is only 0.4 watts. The shielding specifications given in this report will give adequate protection to both the general public and nonradiation workers in areas adjacent to the building as well as radiation workers within the controlled access building.

  16. Advanced Thomson scattering system for high-flux linear plasma generator

    SciTech Connect (OSTI)

    Meiden, H. J. van der; Lof, A. R.; Berg, M. A. van den; Brons, S.; Eck, H. J. N. van; Koelman, P. M. J.; Koppers, W. R.; Kruijt, O. G.; Oyevaar, T.; Prins, P. R.; Rapp, J.; Scholten, J.; Smeets, P. H. M.; Star, G. van der; Zeijlmans van Emmichoven, P. A.; Donne, A. J. H.; Schram, D. C.; Naumenko, N. N.; Tugarinov, S. N.

    2012-12-15

    An advanced Thomson scattering system has been built for a linear plasma generator for plasma surface interaction studies. The Thomson scattering system is based on a Nd:YAG laser operating at the second harmonic and a detection branch featuring a high etendue (f /3) transmission grating spectrometer equipped with an intensified charged coupled device camera. The system is able to measure electron density (n{sub e}) and temperature (T{sub e}) profiles close to the output of the plasma source and, at a distance of 1.25 m, just in front of a target. The detection system enables to measure 50 spatial channels of about 2 mm each, along a laser chord of 95 mm. By summing a total of 30 laser pulses (0.6 J, 10 Hz), an observational error of 3% in n{sub e} and 6% in T{sub e} (at n{sub e}= 9.4 Multiplication-Sign 10{sup 18} m{sup -3}) can be obtained. Single pulse Thomson scattering measurements can be performed with the same accuracy for n{sub e} > 2.8 Multiplication-Sign 10{sup 20} m{sup -3}. The minimum measurable density and temperature are n{sub e} < 1 Multiplication-Sign 10{sup 17} m{sup -3} and T{sub e} < 0.07 eV, respectively. In addition, using the Rayleigh peak, superimposed on the Thomson scattered spectrum, the neutral density (n{sub 0}) of the plasma can be measured with an accuracy of 25% (at n{sub 0}= 1 Multiplication-Sign 10{sup 20} m{sup -3}). In this report, the performance of the Thomson scattering system will be shown along with unprecedented accurate Thomson-Rayleigh scattering measurements on a low-temperature argon plasma expansion into a low-pressure background.

  17. SiD Linear Collider Detector R&D, DOE Final Report

    SciTech Connect (OSTI)

    Brau, James E.; Demarteau, Marcel

    2015-05-15

    The Department of Energy’s Office of High Energy Physics supported the SiD university detector R&D projects in FY10, FY11, and FY12 with no-cost extensions through February, 2015. The R&D projects were designed to advance the SiD capabilities to address the fundamental questions of particle physics at the International Linear Collider (ILC): • What is the mechanism responsible for electroweak symmetry breaking and the generation of mass? • How do the forces unify? • Does the structure of space-time at small distances show evidence for extra dimensions? • What are the connections between the fundamental particles and forces and cosmology? Silicon detectors are used extensively in SiD and are well-matched to the challenges presented by ILC physics and the ILC machine environment. They are fast, robust against machine-induced background, and capable of very fine segmentation. SiD is based on silicon tracking and silicon-tungsten sampling calorimetry, complemented by powerful pixel vertex detection, and outer hadronic calorimetry and muon detection. Radiation hard forward detectors which can be read out pulse by pulse are required. Advanced calorimetry based on a particle flow algorithm (PFA) provides excellent jet energy resolution. The 5 Tesla solenoid is outside the calorimeter to improve energy resolution. PFA calorimetry requires fine granularity for both electromagnetic and hadronic calorimeters, leading naturally to finely segmented silicon-tungsten electromagnetic calorimetry. Since silicon-tungsten calorimetry is expensive, the detector architecture is compact. Precise tracking is achieved with the large magnetic field and high precision silicon microstrips. An ancillary benefit of the large magnetic field is better control of the e⁺e⁻ pair backgrounds, permitting a smaller radius beampipe and improved impact parameter resolution. Finally, SiD is designed with a cost constraint in mind. Significant advances and new capabilities have been made and are described in this report.

  18. CALiPER Report 21.2. Linear (T8) LED Lamp Performance in Five Types of Recessed Troffers

    SciTech Connect (OSTI)

    2014-05-01

    Although lensed troffers are numerous, there are many other types of optical systems as well. This report looks at the performance of three linear (T8) LED lamps—chosen primarily based on their luminous intensity distributions (narrow, medium, and wide beam angles)—as well as a benchmark fluorescent lamp in five different troffer types. Also included are the results of a subjective evaluation. Results show that linear (T8) LED lamps can improve luminaire efficiency in K12-lensed and parabolic-louvered troffers, effect little change in volumetric and high-performance diffuse-lensed type luminaires, but reduce efficiency in recessed indirect troffers. These changes can be accompanied by visual appearance and visual comfort consequences, especially when LED lamps with clear lenses and narrow distributions are installed. Linear (T8) LED lamps with diffuse apertures exhibited wider beam angles, performed more similarly to fluorescent lamps, and received better ratings from observers. Guidance is provided on which luminaires are the best candidates for retrofitting with linear (T8) LED lamps.

  19. Extraction of diffuse correlation spectroscopy flow index by integration of Nth-order linear model with Monte Carlo simulation

    SciTech Connect (OSTI)

    Shang, Yu; Lin, Yu; Yu, Guoqiang; Li, Ting; Chen, Lei; Toborek, Michal

    2014-05-12

    Conventional semi-infinite solution for extracting blood flow index (BFI) from diffuse correlation spectroscopy (DCS) measurements may cause errors in estimation of BFI (αD{sub B}) in tissues with small volume and large curvature. We proposed an algorithm integrating Nth-order linear model of autocorrelation function with the Monte Carlo simulation of photon migrations in tissue for the extraction of αD{sub B}. The volume and geometry of the measured tissue were incorporated in the Monte Carlo simulation, which overcome the semi-infinite restrictions. The algorithm was tested using computer simulations on four tissue models with varied volumes/geometries and applied on an in vivo stroke model of mouse. Computer simulations shows that the high-order (N ≥ 5) linear algorithm was more accurate in extracting αD{sub B} (errors < ±2%) from the noise-free DCS data than the semi-infinite solution (errors: −5.3% to −18.0%) for different tissue models. Although adding random noises to DCS data resulted in αD{sub B} variations, the mean values of errors in extracting αD{sub B} were similar to those reconstructed from the noise-free DCS data. In addition, the errors in extracting the relative changes of αD{sub B} using both linear algorithm and semi-infinite solution were fairly small (errors < ±2.0%) and did not rely on the tissue volume/geometry. The experimental results from the in vivo stroke mice agreed with those in simulations, demonstrating the robustness of the linear algorithm. DCS with the high-order linear algorithm shows the potential for the inter-subject comparison and longitudinal monitoring of absolute BFI in a variety of tissues/organs with different volumes/geometries.

  20. Commissioning of the Varian TrueBeam linear accelerator: A multi-institutional study

    SciTech Connect (OSTI)

    Glide-Hurst, C.; Bellon, M.; Wen, N.; Zhao, B.; Chetty, I. J.; Foster, R.; Speiser, M.; Solberg, T.; Altunbas, C.; Westerly, D.; Miften, M.; Altman, M.

    2013-03-15

    Purpose: Latest generation linear accelerators (linacs), i.e., TrueBeam (Varian Medical Systems, Palo Alto, CA) and its stereotactic counterpart, TrueBeam STx, have several unique features, including high-dose-rate flattening-filter-free (FFF) photon modes, reengineered electron modes with new scattering foil geometries, updated imaging hardware/software, and a novel control system. An evaluation of five TrueBeam linacs at three different institutions has been performed and this work reports on the commissioning experience. Methods: Acceptance and commissioning data were analyzed for five TrueBeam linacs equipped with 120 leaf (5 mm width) MLCs at three different institutions. Dosimetric data and mechanical parameters were compared. These included measurements of photon beam profiles (6X, 6XFFF, 10X, 10XFFF, 15X), photon and electron percent depth dose (PDD) curves (6, 9, 12 MeV), relative photon output factors (Scp), electron cone factors, mechanical isocenter accuracy, MLC transmission, and dosimetric leaf gap (DLG). End-to-end testing and IMRT commissioning were also conducted. Results: Gantry/collimator isocentricity measurements were similar (0.27-0.28 mm), with overall couch/gantry/collimator values of 0.46-0.68 mm across the three institutions. Dosimetric data showed good agreement between machines. The average MLC DLGs for 6, 10, and 15 MV photons were 1.33 {+-} 0.23, 1.57 {+-} 0.24, and 1.61 {+-} 0.26 mm, respectively. 6XFFF and 10XFFF modes had average DLGs of 1.16 {+-} 0.22 and 1.44 {+-} 0.30 mm, respectively. MLC transmission showed minimal variation across the three institutions, with the standard deviation <0.2% for all linacs. Photon and electron PDDs were comparable for all energies. 6, 10, and 15 MV photon beam quality, %dd(10){sub x} varied less than 0.3% for all linacs. Output factors (Scp) and electron cone factors agreed within 0.27%, on average; largest variations were observed for small field sizes (1.2% coefficient of variation, 10 MV, 2 Multiplication-Sign 2 cm{sup 2}) and small cone sizes (<1% coefficient of variation, 6 Multiplication-Sign 6 cm{sup 2} cone), respectively. Conclusions: Overall, excellent agreement was observed in TrueBeam commissioning data. This set of multi-institutional data can provide comparison data to others embarking on TrueBeam commissioning, ultimately improving the safety and quality of beam commissioning.

  1. SU-E-T-74: Commissioning of the Elekta VersaHD Linear Accelerator

    SciTech Connect (OSTI)

    Zhang, Y; Ding, K; Hobbs, R; McNutt, T; Wang, K; Liang, X; Zhu, T

    2014-06-01

    Purpose: To present the commissioning process of recently-released Elekta VersaHD linear accelerator, equipped with Agility 160-leaf multileaf collimator and flattening-filter free (FFF) photon modes. Methods: In addition to routine QA procedures, we adopted an EPID-based method to perform the table rotation and Winston-Lutz tests, and a novel multiradiation isocenter alignment check. The beam data acquired include photon percent-depth dose (PDD) of 6X, 6XFFF, 10X, 10XFFF, and 15X in the field size from 22 to 4040cm{sup 2}, profiles, collimator and phantom scatter factors (Sc and Sp), wedge factor, electron (6, 9, 12, and 15MeV) PDD and profiles, cone and cutout factors, and virtual SSD. Validation measurements were carried out in water tank to evaluate the accuracy of beam modeling by the Pinnacle planning system. End-to-End test and IMRT QA were performed to validate the overall delivery accuracy. A theoretical model has also been used to extract the primary dose ratio and off-axis beam softening effects by fitting photon beam profile measurements. Results: The PDDs of FFF beams with field size 1010cm{sup 2} at 10cm depth, 100cm SSD were intentionally adjusted within 1% of the non-FFF beams. The photon profiles of 3030cm{sup 2} at 10cm depth between non-FFF and FFF beams are very different, OAR(10)=0.74 and 0.63, respectively, for 6XFFF and 10XFFF. The collimator and phantom scatter factors of FFF beam demonstrated smaller variation with field sizes. The EPID-based method demonstrated the maximum deviation between the table rotation axis and radiation isocenter is within 1mm, and the radiation isocenters are within 0.4mm relative to that of 6X. The validation measurement shows less than 2% deviation between the measurement and Pinnacle modeling for most of the test conditions. Conclusion: To the best of our knowledge, this is the first study reporting the Elekta VersaHD commissioning experience, which can be a valuable reference for the radiotherapy community.

  2. A non-linear dimension reduction methodology for generating data-driven stochastic input models

    SciTech Connect (OSTI)

    Ganapathysubramanian, Baskar; Zabaras, Nicholas

    2008-06-20

    Stochastic analysis of random heterogeneous media (polycrystalline materials, porous media, functionally graded materials) provides information of significance only if realistic input models of the topology and property variations are used. This paper proposes a framework to construct such input stochastic models for the topology and thermal diffusivity variations in heterogeneous media using a data-driven strategy. Given a set of microstructure realizations (input samples) generated from given statistical information about the medium topology, the framework constructs a reduced-order stochastic representation of the thermal diffusivity. This problem of constructing a low-dimensional stochastic representation of property variations is analogous to the problem of manifold learning and parametric fitting of hyper-surfaces encountered in image processing and psychology. Denote by M the set of microstructures that satisfy the given experimental statistics. A non-linear dimension reduction strategy is utilized to map M to a low-dimensional region, A. We first show that M is a compact manifold embedded in a high-dimensional input space R{sup n}. An isometric mapping F from M to a low-dimensional, compact, connected set A is contained in R{sup d}(d<

  3. Cyclic Versus Linear Isomers Produced by Reaction of the Methylidyne Radical (CH) with Small Unsaturated Hydrocarbons

    SciTech Connect (OSTI)

    Goulay, Fabien; Trevitt, Adam J.; Meloni, Giovanni; Selby, Talitha M.; Osborn, David L.; Taatjes, Craig A.; Vereecken, Luc; Leone, Stephen R.

    2008-12-05

    The reactions of the methylidyne radical (CH) with ethylene, acetylene, allene, and methylacetylene are studied at room temperature using tunable vacuum ultraviolet (VUV) photoionization and time-resolved mass spectrometry. The CH radicals are prepared by 248 nm multiphoton photolysis of CHBr3 at 298 K and react with the selected hydrocarbon in a helium gas flow. Analysis of photoionization efficiency versus VUV photon wavelength permits isomer-specific detection of the reaction products and allows estimation of the reaction product branching ratios. The reactions proceed by either CH insertion or addition followed by H atom elimination from the intermediate adduct. In the CH + C2H4 reaction the C3H5 intermediate decays by H atom loss to yield 70(+-8)percent allene, 30(+-8)percent methylacetylene and less than 10percent cyclopropene, in agreement with previous RRKM results. In the CH + acetylene reaction, detection of mainly the cyclic C3H2 isomer is contrary to a previous RRKM calculation that predicted linear triplet propargylene to be 90percent of the total H-atom co-products. High-level CBS-APNO quantum calculations and RRKM calculation for the CH + C2H2 reaction presented in this manuscript predict a higher contribution of the cyclic C3H2 (27.0percent) versus triplet propargylene (63.5percent) than these earlier predictions. Extensive calculations on the C3H3 and C3H2D system combined with experimental isotope ratios for the CD + C2H2 reaction indicate that H-atom assisted isomerization in the present experiments is responsible for the discrepancy between the RRKM calculations and the experimental results. Cyclic isomers are also found to represent 30(+-6)percent of the detected products in the case of CH + methylacetylene, together with 33(+-6)percent 1,2,3-butatriene and 37(+-6)percent vinylacetylene. The CH + allene reaction gives 23(+-5)percent 1,2,3-butatriene and 77(+-5)percent vinylacetylene, whereas cyclic isomers are produced below the detection limit in this reaction. The reaction exit channels deduced by comparing the product distributions for the aforementioned reactions are discussed in detail.

  4. Quantification of stromal vascular cell mechanics with a linear cell monolayer rheometer

    SciTech Connect (OSTI)

    Elkins, Claire M. Fuller, Gerald G.; Shen, Wen-Jun; Khor, Victor K.; Kraemer, Fredric B.

    2015-01-15

    Over the past few decades researchers have developed a variety of methods for measuring the mechanical properties of whole cells, including traction force microscopy, atomic force microscopy (AFM), and single-cell tensile testing. Though each of these techniques provides insight into cell mechanics, most also involve some nonideal conditions for acquiring live cell data, such as probing only one portion of a cell at a time, or placing the cell in a nonrepresentative geometry during testing. In the present work, we describe the development of a linear cell monolayer rheometer (LCMR) and its application to measure the mechanics of a live, confluent monolayer of stromal vascular cells. In the LCMR, a monolayer of cells is contacted on both top and bottom by two collagen-coated plates and allowed to adhere. The top plate then shears the monolayer by stepping forward to induce a predetermined step strain, while a force transducer attached to the top plate collects stress information. The stress and strain data are then used to determine the maximum relaxation modulus recorded after step-strain, G{sub r}{sup 0}, referred to as the zero-time relaxation modulus of the cell monolayer. The present study validates the ability of the LCMR to quantify cell mechanics by measuring the change in G{sub r}{sup 0} of a confluent cell monolayer upon the selective inhibition of three major cytoskeletal components (actin microfilaments, vimentin intermediate filaments, and microtubules). The LCMR results indicate that both actin- and vimentin-deficient cells had ?50% lower G{sub r}{sup 0} values than wild-type, whereas tubulin deficiency resulted in ?100% higher G{sub r}{sup 0} values. These findings constitute the first use of a cell monolayer rheometer to quantitatively distinguish the roles of different cytoskeletal elements in maintaining cell stiffness and structure. Significantly, they are consistent with results obtained using single-cell mechanical testing methods, suggesting that the rheology-based LCMR technique may be a useful tool for rapid analysis of cell mechanics by shearing an entire cell monolayer.

  5. Translational-symmetry alternating phase shifting mask grating mark used in a linear measurement model of lithographic projection lens aberrations

    SciTech Connect (OSTI)

    Qiu Zicheng; Wang Xiangzhao; Bi Qunyu; Yuan Qiongyan; Peng Bo; Duan Lifeng

    2009-07-01

    A linear measurement model of lithographic projection lens aberrations is studied numerically based on the Hopkins theory of partially-coherent imaging and positive resist optical lithography (PROLITH) simulation. In this linearity model, the correlation between the mark's structure and its sensitivities to aberrations is analyzed. A method to design a mark with high sensitivity is proved and declared. By use of this method, a translational-symmetry alternating phase shifting mask (Alt-PSM) grating mark is redesigned with all of the even orders, {+-}3rd and {+-}5th order diffraction light missing. In the evaluation simulation, the measurement accuracies of aberrations prove to be enhanced apparently by use of the redesigned mark instead of the old ones.

  6. Seismic Imaging and Inversion: Application of Linear Theory (2012), Cambridge University Press, co-authored with Bob Stolt

    SciTech Connect (OSTI)

    Weglein, Arthur B.; Stolt, Bob H.

    2012-03-01

    Extracting information from seismic data requires knowledge of seismic wave propagation and reflection. The commonly used method involves solving linearly for a reflectivity at every point within the Earth, but this book follows an alternative approach which invokes inverse scattering theory. By developing the theory of seismic imaging from basic principles, the authors relate the different models of seismic propagation, reflection and imaging - thus providing links to reflectivity-based imaging on the one hand and to nonlinear seismic inversion on the other. The comprehensive and physically complete linear imaging foundation developed presents new results at the leading edge of seismic processing for target location and identification. This book serves as a fundamental guide to seismic imaging principles and algorithms and their foundation in inverse scattering theory and is a valuable resource for working geoscientists, scientific programmers and theoretical physicists.

  7. Specific absorption rate calculations of magnetite, using a modified linear response model for applications in magnetic hyperthermia

    SciTech Connect (OSTI)

    Hernndez S, A. E-mail: meduardo2001@hotmail.com; Cano, M. E. E-mail: meduardo2001@hotmail.com; Torres-Arenas, J.

    2014-11-07

    Currently the absorption of electromagnetic radiation by magnetic nanoparticles is studied for biomedical applications of cancer thermotherapy. Several experiments are conduced following the framework of the Rosensweig model, in order to estimate their specific absorption rate. Nevertheless, this linear approximation involves strong simplifications which constrain their accuracy and validity range. The main aim of this work is to incorporate the deviation of the sphericity assumption in particles shapes, to improve the determination of their specific absorption rate. The correction to the effective particles volume is computed as a measure of the apparent amount of magnetic material, interacting with the external AC magnetic field. Preliminary results using the physical properties of Fe3O4 nanoparticles, exhibit an important correction in their estimated specific absorption rate, as a function of the apparent mean particles radius. Indeed, we have observed using a small deviation (6% of the apparent radius), up to 40% of the predicted specific absorption rate by the Rosensweig linear approximation.

  8. Generation and Characterization of Electron Bunches with Ramped Current Profiles in a Dual-Frequency Superconducting Linear Accelerator

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Piot, P.; Behrens, C.; Gerth, C.; Dohlus, M.; Lemery, F.; Mihalcea, D.; Stoltz, P.; Vogt, M.

    2011-09-07

    We report on the successful experimental generation of electron bunches with ramped current profiles. The technique relies on impressing nonlinear correlations in the longitudinal phase space using a superconducing radiofrequency linear accelerator operating at two frequencies and a current-enhancing dispersive section. The produced {approx} 700-MeV bunches have peak currents of the order of a kilo-Ampere. Data taken for various accelerator settings demonstrate the versatility of the method and in particular its ability to produce current profiles that have a quasi-linear dependency on the longitudinal (temporal) coordinate. The measured bunch parameters are shown, via numerical simulations, to produce gigavolt-per-meter peak acceleratingmore » electric fields with transformer ratios larger than 2 in dielectric-lined waveguides.« less

  9. Applications of exact linearization techniques for steady-state stability enhancement in a weak ac/dc system

    SciTech Connect (OSTI)

    Kaprielian, S.; Clements, K. ); Turi, J. )

    1992-05-01

    A nonlinear control strategy to improve the steady-state stability of a weak AC/DC power system is presented. The approach described in this paper is based on the extension of feedback linearization techniques to nonlinear descriptor system models. This method produces a nonlinear control strategy which is capable of enhancing system performance for various system operating conditions. This claim is supported with simulation results.

  10. The Silicon Detector (SiD) And Linear Collider Detector R&D in Asia And North America

    SciTech Connect (OSTI)

    Brau, J.E.; Breidenbach, M.; Fujii, Y.; /KEK, Tsukuba

    2005-08-11

    In Asia and North America research and development on a linear collider detector has followed complementary paths to that in Europe. Among the developments in the US has been the conception of a detector built around silicon tracking, which relies heavily on a pixel (CCD) vertex detector, and employs a silicon tungsten calorimeter. Since this detector is quite different from the TESLA detector, we describe it here, along with some of the sub-system specific R&D in these regions.

  11. Nuclear matter properties in the non-linear Walecka model at finite temperature with interaction between the ? - ? mesons

    SciTech Connect (OSTI)

    Costa, R. S.; Cortes, M. R.; Nunes, D. R.; Batista, A. S. A.

    2014-11-11

    In this work in contrast to the usual Walecka model [1] we include the interaction between the ? ? mesons [2,3] with the aim of studying the nuclear matter properties in the relativistic mean-field theory in the regime of high temperatures. Therefore in our work we use the non-linear Walecka model. We investigate whether the phase transition characteristic of other models without these interactions vanishes for a given value of chemical potential ? and baryon density ?{sub N}.

  12. Electromagnetic momentum and the energymomentum tensor in a linear medium with magnetic and dielectric properties

    SciTech Connect (OSTI)

    Crenshaw, Michael E.

    2014-04-15

    In a continuum setting, the energymomentum tensor embodies the relations between conservation of energy, conservation of linear momentum, and conservation of angular momentum. The well-defined total energy and the well-defined total momentum in a thermodynamically closed system with complete equations of motion are used to construct the total energymomentum tensor for a stationary simple linear material with both magnetic and dielectric properties illuminated by a quasimonochromatic pulse of light through a gradient-index antireflection coating. The perplexing issues surrounding the Abraham and Minkowski momentums are bypassed by working entirely with conservation principles, the total energy, and the total momentum. We derive electromagnetic continuity equations and equations of motion for the macroscopic fields based on the material four-divergence of the traceless, symmetric total energymomentum tensor. We identify contradictions between the macroscopic Maxwell equations and the continuum form of the conservation principles. We resolve the contradictions, which are the actual fundamental issues underlying the AbrahamMinkowski controversy, by constructing a unified version of continuum electrodynamics that is based on establishing consistency between the three-dimensional Maxwell equations for macroscopic fields, the electromagnetic continuity equations, the four-divergence of the total energymomentum tensor, and a four-dimensional tensor formulation of electrodynamics for macroscopic fields in a simple linear medium.

  13. Phospholipid fatty acid biomarkers in a freshwater periphyton community exposed to uranium: discovery by non-linear statistical learning

    SciTech Connect (OSTI)

    Webb-Robertson, Bobbie-Jo M.; Bunn, Amoret L.; Bailey, Vanessa L.

    2011-01-01

    Phospholipid fatty acids (PLFA) have been widely used to characterize environmental microbial communities, generating community profiles that can distinguish phylogenetic or functional groups within the community. The poor specificity of organism groups with fatty acid biomarkers in the classic PLFA-microorganism associations is a confounding factor in many of the statistical classification/clustering approaches traditionally used to interpret PLFA profiles. In this paper we demonstrate that non-linear statistical learning methods, such as a support vector machine (SVM), can more accurately find patterns related to uranyl nitrate exposure in a freshwater periphyton community than linear methods, such as partial least squares discriminant analysis. In addition, probabilistic models of exposure can be derived from the identified lipid biomarkers to demonstrate the potential model-based approach that could be used in remediation. The SVM probability model separates dose groups at accuracies of ~87.0%, ~71.4%, ~87.5%, and 100% for the four groups; Control (non-amended system), low-dose (amended at 10 g U L-1), medium dose (amended at 100 g U L-1), and high dose (500 g U L-1). The SVM model achieved an overall cross-validated classification accuracy of ~87% in contrast to ~59% for the best linear classifier.

  14. The use of artificial neural networks and multiple linear regression to predict rate of medical waste generation

    SciTech Connect (OSTI)

    Jahandideh, Sepideh Jahandideh, Samad; Asadabadi, Ebrahim Barzegari; Askarian, Mehrdad; Movahedi, Mohammad Mehdi; Hosseini, Somayyeh; Jahandideh, Mina

    2009-11-15

    Prediction of the amount of hospital waste production will be helpful in the storage, transportation and disposal of hospital waste management. Based on this fact, two predictor models including artificial neural networks (ANNs) and multiple linear regression (MLR) were applied to predict the rate of medical waste generation totally and in different types of sharp, infectious and general. In this study, a 5-fold cross-validation procedure on a database containing total of 50 hospitals of Fars province (Iran) were used to verify the performance of the models. Three performance measures including MAR, RMSE and R{sup 2} were used to evaluate performance of models. The MLR as a conventional model obtained poor prediction performance measure values. However, MLR distinguished hospital capacity and bed occupancy as more significant parameters. On the other hand, ANNs as a more powerful model, which has not been introduced in predicting rate of medical waste generation, showed high performance measure values, especially 0.99 value of R{sup 2} confirming the good fit of the data. Such satisfactory results could be attributed to the non-linear nature of ANNs in problem solving which provides the opportunity for relating independent variables to dependent ones non-linearly. In conclusion, the obtained results showed that our ANN-based model approach is very promising and may play a useful role in developing a better cost-effective strategy for waste management in future.

  15. International Linear Collider Reference Design Report Volume 2: Physics at the ILC

    SciTech Connect (OSTI)

    Aarons, Gerald; Abe, Toshinori; Abernathy, Jason; Ablikim, Medina; Abramowicz, Halina; Adey, David; Adloff, Catherine; Adolphsen, Chris; Afanaciev, Konstantin; Agapov, Ilya; Ahn, Jung-Keun; Aihara, Hiroaki; Akemoto, Mitsuo; del Carmen Alabau, Maria; Albert, Justin; Albrecht, Hartwig; Albrecht, Michael; Alesini, David; Alexander, Gideon; Alexander, Jim; Allison, Wade; /SLAC /Tokyo U. /Victoria U. /Beijing, Inst. High Energy Phys. /Tel Aviv U. /Birmingham U. /Annecy, LAPP /Minsk, High Energy Phys. Ctr. /DESY /Royal Holloway, U. of London /CERN /Pusan Natl. U. /KEK, Tsukuba /Orsay, LAL /Notre Dame U. /Frascati /Cornell U., Phys. Dept. /Oxford U. /Hefei, CUST /Bangalore, Indian Inst. Sci. /Fermilab

    2011-11-14

    The triumph of 20th century particle physics was the development of the Standard Model and the confirmation of many of its aspects. Experiments determined the particle constituents of ordinary matter, and identified four forces that hold matter together and transform it from one form to another. Particle interactions were found to obey precise laws of relativity and quantum theory. Remarkable features of quantum physics were observed, including the real effects of 'virtual' particles on the visible world. Building on this success, particle physicists are now able to address questions that are even more fundamental, and explore some of the deepest mysteries in science. The scope of these questions is illustrated by this summary from the report Quantum Universe: (1) Are there undiscovered principles of nature; (2) How can we solve the mystery of dark energy; (3) Are there extra dimensions of space; (4) Do all the forces become one; (5) Why are there so many particles; (6) What is dark matter? How can we make it in the laboratory; (7) What are neutrinos telling us; (8) How did the universe begin; and (9) What happened to the antimatter? A worldwide program of particle physics investigations, using multiple approaches, is already underway to explore this compelling scientific landscape. As emphasized in many scientific studies, the International Linear Collider is expected to play a central role in what is likely to be an era of revolutionary advances. Discoveries from the ILC could have breakthrough impact on many of these fundamental questions. Many of the scientific opportunities for the ILC involve the Higgs particle and related new phenomena at Terascale energies. The Standard Model boldly hypothesizes a new form of Terascale energy, called the Higgs field, that permeates the entire universe. Elementary particles acquire mass by interacting with this field. The Higgs field also breaks a fundamental electroweak force into two forces, the electromagnetic and weak forces, which are observed by experiments in very different forms. So far, there is no direct experimental evidence for a Higgs field or the Higgs particle that should accompany it. Furthermore, quantum effects of the type already observed in experiments should destabilize the Higgs boson of the Standard Model, preventing its operation at Terascale energies. The proposed antidotes for this quantum instability mostly involve dramatic phenomena at the Terascale: new forces, a new principle of nature called supersymmetry, or even extra dimensions of space. Thus for particle physicists the Higgs boson is at the center of a much broader program of discovery, taking off from a long list of questions. Is there really a Higgs boson? If not, what are the mechanisms that give mass to particles and break the electroweak force? If there is a Higgs boson, does it differ from the hypothetical Higgs of the Standard Model? Is there more than one Higgs particle? What are the new phenomena that stabilize the Higgs boson at the Terascale? What properties of Higgs boson inform us about these new phenomena? Another major opportunity for the ILC is to shed light on the dark side of the universe. Astrophysical data shows that dark matter dominates over visible matter, and that almost all of this dark matter cannot be composed of known particles. This data, combined with the concordance model of Big Bang cosmology, suggests that dark matter is comprised of new particles that interact weakly with ordinary matter and have Terascale masses. It is truely remarkable that astrophysics and cosmology, completely independently of the particle physics considerations reviewed above, point to new phenomena at the Terascale. If Terascale dark matter exists, experiments at the ILC should be able to produce such particles in the laboratory and study their properties. Another list of questions will then beckon. Do these new particles really have the correct properties to be the dark matter? Do they account for all of the dark matter, or only part of it? What do their properties tell us about the evolution of the universe? How is dark matter connected to new principles or forces of nature? A third cluster of scientific opportunities for the ILC focus on Einstein's vision of an ultimate unified theory. Particle physics data already suggests that three of the fundamental forces originated from a single 'grand' unified force in the first instant of the Big Bang. Experiments at the ILC could test this idea and look for evidence of a related unified origin of matter involving supersymmetry. A theoretical framework called string theory goes beyond grand unification to include gravity, extra spatial dimensions, and new fundamental entities called superstrings. Theoretical models to explain the properties of neutrinos, and account for the mysterious dominance of matter over antimatter, also posit unification at high energies.

  16. News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Monochromator Installed The new multilayer monochromator has been installed by Oxford Danfysik. In the coming months the monochromator will undergo commissioning by the...

  17. WATER PRODUCTION IN COMETS 2001 Q4 (NEAT) AND 2002 T7 (LINEAR) DETERMINED FROM SOHO/SWAN OBSERVATIONS

    SciTech Connect (OSTI)

    Combi, M. R.; Lee, Y.; Maekinen, J. T. T.; Bertaux, J.-L.; Quemerais, E.

    2009-06-15

    The SWAN all-sky camera on the Solar and Heliospheric Observatory (SOHO) spacecraft detected the hydrogen Lyman-alpha (Ly{alpha}) comae of comets 2001 Q4 NEAT and 2002 T7 LINEAR for large portions of their perihelion apparitions in 2003 and 2004. C/2001 Q4 NEAT was observed from 2003 September 14 through 2004 November 2, covering heliocentric distances from 3.23 AU before perihelion to 2.75 AU after, and C/2002 T7 LINEAR was observed from 2003 December 4 through 2004 August 6, covering heliocentric distances from 2.52 AU before perihelion to 2.09 AU after. We combined the full set of comet specific and full-sky observations and used our time-resolved model (TRM), which enables us to extract continuous values of the daily-average value of the water production rate throughout most of this entire period. The average power-law fit to the production rate variation of C/2001 Q4 NEAT with heliocentric distance, r, gives 3.5 x 10{sup 29} r {sup -1.7} and that for C/2002 T7 LINEAR gives 4.6 x 10{sup 29} r {sup -2.0}. Both comets show roughly a factor of 2 asymmetry in activity about perihelion, being more active before perihelion. C/2001 Q4 NEAT showed a production rate outburst about 30 days before perihelion (2004 April 15) and then a large extended increase above the nominal trend from 50 to 70 days after perihelion (2004 July 5-July 25)

  18. Linear mode conversion of Langmuir/z-mode waves to radiation in plasmas with various magnetic field strength

    SciTech Connect (OSTI)

    Kim, Eun-Hwa; Johnson, Jay R.; Cairns, Iver H.

    2013-12-15

    Linear mode conversion of Langmuir/z waves to electromagnetic radiation near the plasma and upper hybrid frequency in the presence of density gradients is potentially relevant to type II and III solar radio bursts, ionospheric radar experiments, pulsars, and continuum radiation for planetary magnetospheres. Here, we study mode conversion in warm, magnetized plasmas using a numerical electron fluid simulation code when the density gradient has a wide range of angle, ?, to the ambient magnetic field, B{sub 0}, for a range of incident Langmuir/z wavevectors. Our results include: (1) Left-handed polarized ordinary (oL) and right-handed polarized extraordinary (xR) mode waves are produced in various ranges of ? for ?{sub 0} = (?L/c){sup 1/3}(?{sub ce}/?) < 1.5, where ?{sub ce} is the (angular) electron cyclotron frequency, ? is the angular wave frequency, L is the length scale of the (linear) density gradient, and c is the speed of light; (2) the xR mode is produced most strongly in the range, 40 < ? < 60, for intermediately magnetized plasmas with ?{sub 0} = 1.0 and 1.5, while it is produced over a wider range, 0 ? ? ? 90, for weakly magnetized plasmas with ?{sub 0} = 0.1 and 0.7; (3) the maximum total conversion efficiencies for wave power from the Langmuir/z mode to radiation are of order 50%99% and the corresponding energy conversion efficiencies are 5%14% (depending on the adiabatic index ? and ? = T{sub e}/m{sub e}c{sup 2}, where T{sub e} is the electron temperature and m{sub e} is the electron) for various ?{sub 0}; (4) the mode conversion window becomes wider as ?{sub 0} and ? increase. Hence, the results in this paper confirm that linear mode conversion under these conditions can explain the weak total circular polarization of interplanetary type II and III solar radio bursts because a strong xR mode can be generated via linear mode conversion near ? ? 45.

  19. System for measuring temporal profiles of scintillation at high and different linear energy transfers by using pulsed ion beams

    SciTech Connect (OSTI)

    Koshimizu, Masanori Asai, Keisuke; Kurashima, Satoshi; Taguchi, Mitsumasa; Kimura, Atsushi; Iwamatsu, Kazuhiro

    2015-01-15

    We have developed a system for measuring the temporal profiles of scintillation at high linear energy transfer (LET) by using pulsed ion beams from a cyclotron. The half width at half maximum time resolution was estimated to be 1.52.2 ns, which we attributed mainly to the duration of the pulsed ion beam and timing jitter between the trigger signal and the arrival of the ion pulse. The temporal profiles of scintillation of BaF{sub 2} at different LETs were successfully observed. These results indicate that the proposed system is a powerful tool for analyzing the LET effects in temporal profiles of scintillation.

  20. Non-linear mode interaction between spin torque driven and damped modes in spin torque nano-oscillators

    SciTech Connect (OSTI)

    Romera, M.; Monteblanco, E.; Garcia-Sanchez, F.; Buda-Prejbeanu, L. D.; Ebels, U.; Delaët, B.

    2015-05-11

    The influence of dynamic coupling in between magnetic layers of a standard spin torque nano-oscillator composed of a synthetic antiferromagnet (SyF) as a polarizer and an in-plane magnetized free layer has been investigated. Experiments on spin valve nanopillars reveal non-continuous features such as kinks in the frequency field dependence that cannot be explained without such interactions. Comparison of experiments to numerical macrospin simulations shows that this is due to non-linear interaction between the spin torque (STT) driven mode and a damped mode that is mediated via the third harmonics of the STT mode. It only occurs at large applied currents and thus at large excitation amplitudes of the STT mode. Under these conditions, a hybridized mode characterized by a strong reduction of the linewidth appears. The reduced linewidth can be explained by a reduction of the non-linear contribution to the linewidth via an enhanced effective damping. Interestingly, the effect depends also on the exchange interaction within the SyF. An enhancement of the current range of reduced linewidth by a factor of two and a reduction of the minimum linewidth by a factor of two are predicted from simulation when the exchange interaction strength is reduced by 30%. These results open directions to optimize the design and microwave performances of spin torque nano-oscillators taking advantage of the coupling mechanisms.