National Library of Energy BETA

Sample records for large emitter intending

  1. Large area InN terahertz emitters based on the lateral photo-Dember effect

    SciTech Connect (OSTI)

    Wallauer, Jan Grumber, Christian; Walther, Markus; Polyakov, Vladimir; Iannucci, Robert; Cimalla, Volker; Ambacher, Oliver

    2015-09-14

    Large area terahertz emitters based on the lateral photo-Dember effect in InN (indium nitride) are presented. The formation of lateral photo-Dember currents is induced by laser-illumination through a microstructured metal cover processed onto the InN substrate, causing an asymmetry in the lateral photogenerated charge carrier distribution. Our design uses simple metal structures, which are produced by conventional two-dimensional micro-structuring techniques. Having favoring properties as a photo-Dember material InN is particularly well-suited as a substrate for our emitters. We demonstrate that the emission intensity of the emitters can be significantly influenced by the structure of the metal cover leaving room for improvement by optimizing the masking structures.

  2. Thermophotovoltaic conversion using selective infrared line emitters and large band gap photovoltaic devices

    DOE Patents [OSTI]

    Brandhorst, Jr., Henry W.; Chen, Zheng

    2000-01-01

    Efficient thermophotovoltaic conversion can be performed using photovoltaic devices with a band gap in the 0.75-1.4 electron volt range, and selective infrared emitters chosen from among the rare earth oxides which are thermally stimulated to emit infrared radiation whose energy very largely corresponds to the aforementioned band gap. It is possible to use thermovoltaic devices operating at relatively high temperatures, up to about 300.degree. C., without seriously impairing the efficiency of energy conversion.

  3. Optimization and beam control in large-emittance accelerators: Neutrino factories;

    SciTech Connect (OSTI)

    Carol Johnstone

    2004-08-23

    Schemes for intense sources of high-energy muons require collection, rf capture, and transport of particle beams with unprecedented emittances, both longitudinally and transversely. These large emittances must be reduced or ''cooled'' both in size and in energy spread before the muons can be efficiently accelerated. Therefore, formation of muon beams sufficiently intense to drive a Neutrino Factory or Muon Collider requires multi-stage preparation. Further, because of the large beam phase space which must be successfully controlled, accelerated, and transported, the major stages that comprise such a facility: proton driver, production, capture, phase rotation, cooling, acceleration, and storage are complex and strongly interlinked. Each of the stages must be consecutively matched and simultaneously optimized with upstream and downstream systems, meeting challenges not only technically in the optics and component design, but also in the modeling of both new and extended components. One design for transverse cooling, for example, employs meter-diameter solenoids to maintain strong focusing--300-500 mr beam divergences--across ultra-large momentum ranges, {ge} {+-}20% {delta}p/p, defying conventional approximations to the dynamics and field representation. To now, the interplay of the different systems and staging strategies has not been formally addressed. This work discusses two basic, but different approaches to a Neutrino Factory and how the staging strategy depends on beam parameters and method of acceleration.

  4. Pulsed hybrid field emitter

    DOE Patents [OSTI]

    Sampayan, S.E.

    1998-03-03

    A hybrid emitter exploits the electric field created by a rapidly depoled ferroelectric material. Combining the emission properties of a planar thin film diamond emitter with a ferroelectric alleviates the present technological problems associated with both types of emitters and provides a robust, extremely long life, high current density cathode of the type required by emerging microwave power generation, accelerator technology and display applications. This new hybrid emitter is easy to fabricate and not susceptible to the same failures which plague microstructure field emitter technology. Local electrode geometries and electric field are determined independently from those for optimum transport and brightness preservation. Due to the large amount of surface charge created on the ferroelectric, the emitted electrons have significant energy, thus eliminating the requirement for specialized phosphors in emissive flat-panel displays. 11 figs.

  5. Pulsed hybrid field emitter

    DOE Patents [OSTI]

    Sampayan, Stephen E.

    1998-01-01

    A hybrid emitter exploits the electric field created by a rapidly depoled ferroelectric material. Combining the emission properties of a planar thin film diamond emitter with a ferroelectric alleviates the present technological problems associated with both types of emitters and provides a robust, extremely long life, high current density cathode of the type required by emerging microwave power generation, accelerator technology and display applications. This new hybrid emitter is easy to fabricate and not susceptible to the same failures which plague microstructure field emitter technology. Local electrode geometries and electric field are determined independently from those for optimum transport and brightness preservation. Due to the large amount of surface charge created on the ferroelectric, the emitted electrons have significant energy, thus eliminating the requirement for specialized phosphors in emissive flat-panel displays.

  6. FACET Emittance Growth

    SciTech Connect (OSTI)

    Frederico, J; Hogan, M.J.; Nosochkov, Y.; Litos, M.D.; Raubenheimer, T.; /SLAC

    2011-04-05

    FACET, the Facility for Advanced Accelerator and Experimental Tests, is a new facility being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration. The FACET beamline consists of a chicane and final focus system to compress the 23 GeV, 3.2 nC electron bunches to {approx}20 {micro}m long and {approx}10 {micro}m wide. Simulations of the FACET beamline indicate the short-duration and large, 1.5% rms energy spread beams may suffer a factor of four emittance growth from a combination of chromaticity, incoherent synchrotron radiation (ISR), and coherent synchrotron radiation (CSR). Emittance growth is directly correlated to head erosion in plasma wakefield acceleration and is a limiting factor in single stage performance. Studies of the geometric, CSR, and ISR components are presented. Numerical calculation of the rms emittance can be overwhelmed by long tails in the simulated phase space distributions; more useful definitions of emittance are given. A complete simulation of the beamline is presented as well, which agrees with design specifications.

  7. Asymmetrical field emitter

    DOE Patents [OSTI]

    Fleming, James G.; Smith, Bradley K.

    1995-01-01

    Providing a field emitter with an asymmetrical emitter structure having a very sharp tip in close proximity to its gate. One preferred embodiment of the present invention includes an asymmetrical emitter and a gate. The emitter having a tip and a side is coupled to a substrate. The gate is connected to a step in the substrate. The step has a top surface and a side wall that is substantially parallel to the side of the emitter. The tip of the emitter is in close proximity to the gate. The emitter is at an emitter potential, and the gate is at a gate potential such that with the two potentials at appropriate values, electrons are emitted from the emitter. In one embodiment, the gate is separated from the emitter by an oxide layer, and the emitter is etched anisotropically to form its tip and its asymmetrical structure.

  8. Asymmetrical field emitter

    DOE Patents [OSTI]

    Fleming, J.G.; Smith, B.K.

    1995-10-10

    A method is disclosed for providing a field emitter with an asymmetrical emitter structure having a very sharp tip in close proximity to its gate. One preferred embodiment of the present invention includes an asymmetrical emitter and a gate. The emitter having a tip and a side is coupled to a substrate. The gate is connected to a step in the substrate. The step has a top surface and a side wall that is substantially parallel to the side of the emitter. The tip of the emitter is in close proximity to the gate. The emitter is at an emitter potential, and the gate is at a gate potential such that with the two potentials at appropriate values, electrons are emitted from the emitter. In one embodiment, the gate is separated from the emitter by an oxide layer, and the emitter is etched anisotropically to form its tip and its asymmetrical structure. 17 figs.

  9. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1990-10-16

    A support is presented for use in a thermionic converted to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially at its temperatures changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a large metal main support at the rear end that is attached to the housing, and metal main support. The spring structure can include a loose wafer captured between the Belleville springs.

  10. Highly directional thermal emitter

    DOE Patents [OSTI]

    Ribaudo, Troy; Shaner, Eric A; Davids, Paul; Peters, David W

    2015-03-24

    A highly directional thermal emitter device comprises a two-dimensional periodic array of heavily doped semiconductor structures on a surface of a substrate. The array provides a highly directional thermal emission at a peak wavelength between 3 and 15 microns when the array is heated. For example, highly doped silicon (HDSi) with a plasma frequency in the mid-wave infrared was used to fabricate nearly perfect absorbing two-dimensional gratings structures that function as highly directional thermal radiators. The absorption and emission characteristics of the HDSi devices possessed a high degree of angular dependence for infrared absorption in the 10-12 micron range, while maintaining high reflectivity of solar radiation (.about.64%) at large incidence angles.

  11. Photonically Engineered Incandescent Emitter

    DOE Patents [OSTI]

    Gee, James M.; Lin, Shawn-Yu; Fleming, James G.; Moreno, James B.

    2005-03-22

    A photonically engineered incandescence is disclosed. The emitter materials and photonic crystal structure can be chosen to modify or suppress thermal radiation above a cutoff wavelength, causing the emitter to selectively emit in the visible and near-infrared portions of the spectrum. An efficient incandescent lamp is enabled thereby. A method for fabricating a three-dimensional photonic crystal of a structural material, suitable for the incandescent emitter, is also disclosed.

  12. Photonically engineered incandescent emitter

    DOE Patents [OSTI]

    Gee, James M.; Lin, Shawn-Yu; Fleming, James G.; Moreno, James B.

    2003-08-26

    A photonically engineered incandescence is disclosed. The emitter materials and photonic crystal structure can be chosen to modify or suppress thermal radiation above a cutoff wavelength, causing the emitter to selectively emit in the visible and near-infrared portions of the spectrum. An efficient incandescent lamp is enabled thereby. A method for fabricating a three-dimensional photonic crystal of a structural material, suitable for the incandescent emitter, is also disclosed.

  13. Diamond fiber field emitters

    DOE Patents [OSTI]

    Blanchet-Fincher, Graciela B.; Coates, Don M.; Devlin, David J.; Eaton, David F.; Silzars, Aris K.; Valone, Steven M.

    1996-01-01

    A field emission electron emitter comprising an electrode formed of at least one diamond, diamond-like carbon or glassy carbon composite fiber, said composite fiber having a non-diamond core and a diamond, diamond-like carbon or glassy carbon coating on said non-diamond core, and electronic devices employing such a field emission electron emitter.

  14. Electrochemical formation of field emitters

    DOE Patents [OSTI]

    Bernhardt, Anthony F.

    1999-01-01

    Electrochemical formation of field emitters, particularly useful in the fabrication of flat panel displays. The fabrication involves field emitting points in a gated field emitter structure. Metal field emitters are formed by electroplating and the shape of the formed emitter is controlled by the potential imposed on the gate as well as on a separate counter electrode. This allows sharp emitters to be formed in a more inexpensive and manufacturable process than vacuum deposition processes used at present. The fabrication process involves etching of the gate metal and the dielectric layer down to the resistor layer, and then electroplating the etched area and forming an electroplated emitter point in the etched area.

  15. Diamond-graphite field emitters

    DOE Patents [OSTI]

    Valone, Steven M.

    1997-01-01

    A field emission electron emitter comprising an electrode of diamond and a conductive carbon, e.g., graphite, is provided.

  16. Monolithic multinozzle emitters for nanoelectrospray mass spectrometry

    DOE Patents [OSTI]

    Wang, Daojing; Yang, Peidong; Kim, Woong; Fan, Rong

    2011-09-20

    Novel and significantly simplified procedures for fabrication of fully integrated nanoelectrospray emitters have been described. For nanofabricated monolithic multinozzle emitters (NM.sup.2 emitters), a bottom up approach using silicon nanowires on a silicon sliver is used. For microfabricated monolithic multinozzle emitters (M.sup.3 emitters), a top down approach using MEMS techniques on silicon wafers is used. The emitters have performance comparable to that of commercially-available silica capillary emitters for nanoelectrospray mass spectrometry.

  17. Electrochemical formation of field emitters

    DOE Patents [OSTI]

    Bernhardt, A.F.

    1999-03-16

    Electrochemical formation of field emitters, particularly useful in the fabrication of flat panel displays is disclosed. The fabrication involves field emitting points in a gated field emitter structure. Metal field emitters are formed by electroplating and the shape of the formed emitter is controlled by the potential imposed on the gate as well as on a separate counter electrode. This allows sharp emitters to be formed in a more inexpensive and manufacturable process than vacuum deposition processes used at present. The fabrication process involves etching of the gate metal and the dielectric layer down to the resistor layer, and then electroplating the etched area and forming an electroplated emitter point in the etched area. 12 figs.

  18. Amorphous-diamond electron emitter

    DOE Patents [OSTI]

    Falabella, Steven

    2001-01-01

    An electron emitter comprising a textured silicon wafer overcoated with a thin (200 .ANG.) layer of nitrogen-doped, amorphous-diamond (a:D-N), which lowers the field below 20 volts/micrometer have been demonstrated using this emitter compared to uncoated or diamond coated emitters wherein the emission is at fields of nearly 60 volts/micrometer. The silicon/nitrogen-doped, amorphous-diamond (Si/a:D-N) emitter may be produced by overcoating a textured silicon wafer with amorphous-diamond (a:D) in a nitrogen atmosphere using a filtered cathodic-arc system. The enhanced performance of the Si/a:D-N emitter lowers the voltages required to the point where field-emission displays are practical. Thus, this emitter can be used, for example, in flat-panel emission displays (FEDs), and cold-cathode vacuum electronics.

  19. EMITTANCE COMPENSATION FOR MAGNETIZED BEAMS

    SciTech Connect (OSTI)

    KEWISCH,J.; CHANG, X.

    2007-06-25

    Emittance compensation is a well established technique for minimizing the emittance of an electron beam from a RF photo-cathode gun. Longitudinal slices of a bunch have a small emittance, but due to the longitudinal charge distribution of the bunch and time dependent RF fields they are not focused in the same way, so that the direction of their phase ellipses diverges in phase space and the projected emittance is much larger. Emittance compensation reverses the divergence. At the location where the slopes of the phase ellipses coincide the beam is accelerated, so that the space charge forces are reduced. A recipe for emittance compensation is given in. For magnetized beams (where the angular momentum is non-zero) such emittance compensation is not sufficient because variations in the slice radius lead to variations in the angular speed and therefore to an increase of emittance in the rotating game. We describe a method and tools for a compensation that includes the beam magnetization.

  20. Transverse Emittance Reduction with Tapered Foil (Conference...

    Office of Scientific and Technical Information (OSTI)

    and also analyzed the emittance growth from the associated multiple coulomb scattering. ... To calculate the eigen emittances, it requires only to know the beam distribution at the ...

  1. Diamondoid monolayers as electron emitters

    DOE Patents [OSTI]

    Yang, Wanli; Fabbri, Jason D.; Melosh, Nicholas A.; Hussain, Zahid; Shen, Zhi-Xun

    2013-10-29

    Provided are electron emitters based upon diamondoid monolayers, preferably self-assembled higher diamondoid monolayers. High intensity electron emission has been demonstrated employing such diamondoid monolayers, particularly when the monolayers are comprised of higher diamondoids. The application of such diamondoid monolayers can alter the band structure of substrates, as well as emit monochromatic electrons, and the high intensity electron emissions can also greatly improve the efficiency of field-effect electron emitters as applied to industrial and commercial applications.

  2. Diamondoid monolayers as electron emitters

    DOE Patents [OSTI]

    Yang, Wanli; Fabbri, Jason D.; Melosh, Nicholas A.; Hussain, Zahid; Shen, Zhi-Xun

    2012-04-10

    Provided are electron emitters based upon diamondoid monolayers, preferably self-assembled higher diamondoid monolayers. High intensity electron emission has been demonstrated employing such diamondoid monolayers, particularly when the monolayers are comprised of higher diamondoids. The application of such diamondoid monolayers can alter the band structure of substrates, as well as emit monochromatic electrons, and the high intensity electron emissions can also greatly improve the efficiency of field-effect electron emitters as applied to industrial and commercial applications.

  3. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1990-05-22

    This patent describes a support provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs.

  4. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1989-07-06

    This document discusses a support provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs. 7 figs.

  5. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, Daniel T.

    1990-01-01

    A support is provided for use in a thermionic converter to support an end an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially at its temperatures changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housng, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  6. Thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, Daniel T.

    1990-01-01

    A support is provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  7. Emittance and Phase Space Tomography for the Fermilab Linac

    SciTech Connect (OSTI)

    Garcia, F.G.G.; Johnstone, C.; Kobilarcik, T.; Koizumi, G.M.; Moore, C.D.; Newhart, D.L.; /Fermilab

    2012-05-01

    large emittance measured.

  8. Elementary framework for cold field emission from quantum-confined, non-planar emitters

    SciTech Connect (OSTI)

    Patterson, A. A. Akinwande, A. I.

    2015-05-07

    For suitably small field emitters, the effects of quantum confinement at the emitter tip may have a significant impact on the emitter performance and total emitted current density (ECD). Since the geometry of a quantum system uniquely determines the magnitude and distribution of its energy levels, a framework for deriving ECD equations from cold field electron emitters of arbitrary geometry and dimensionality is developed. In the interest of obtaining semi-analytical ECD equations, the framework is recast in terms of plane wave solutions to the Schrdinger equation via the use of the Jeffreys-Wentzel-Kramers-Brillouin approximation. To demonstrate the framework's consistency with our previous work and its capabilities in treating emitters with non-planar geometries, ECD equations were derived for the normally unconfined cylindrical nanowire (CNW) and normally confined (NC) CNW emitter geometries. As a function of the emitter radius, the NC CNW emitter ECD profile displayed a strong dependence on the Fermi energy and had an average ECD that exceeded the Fowler-Nordheim equation for typical values of the Fermi energy due to closely spaced, singly degenerate energy levels (excluding electron spin), comparatively large electron supply values, and the lack of a transverse, zero-point energy. Such characteristics suggest that emitters with non-planar geometries may be ideal for emission from both an electron supply and electrostatics perspective.

  9. Electromagnetic interference impact of the proposed emitters for the High Frequency Active Auroral Research Program (HAARP). Interim report

    SciTech Connect (OSTI)

    Robertshaw, G.A.; Snyder, A.L.; Weiner, M.M.

    1993-05-14

    The proposed HAARP emitters at the Gakona (Alaska) preferred site and at the Clear AFS (Alaska) alternative site are the Ionospheric Research Instrument (IRI), the Incoherent Scatter Radar (ISR), and the Vertical Incidence Sounder(VIS). The electromagnetic interference (EMI) impact of those emitters on receiving systems in the vicinity of the sites is estimated in this study. The results are intended for use as an input to the Air Force Environmental Impact Statement as part of the Environmental Impact Analysis Process.

  10. Membrane-Based Emitter for Coupling Microfluidics with Ultrasensitive Nanoelectrospray Ionization-Mass Spectrometry

    SciTech Connect (OSTI)

    Sun, Xuefei; Kelly, Ryan T.; Tang, Keqi; Smith, Richard D.

    2011-06-09

    An integrated poly(dimethylsiloxane) (PDMS) membrane-based microfluidic emitter for high performance nanoelectrospray ionization-mass spectrometry (nanoESI-MS) has been fabricated and evaluated. The ~100-?m-thick emitter was created by cutting a PDMS membrane that protrudes beyond the bulk substrate. The reduced surface area at the emitter enhances the electric field and reduces wetting of the surface by the electrospray solvent. As such, the emitter provides highly stable electrospray at flow rates as low as 10 nL/min, and is compatible with electrospray solvents containing a large organic component (e.g., 90% methanol). This approach enables facile emitter construction, and provides excellent stability, reproducibility and sensitivity, as well as compatibility with multilayer soft lithography.

  11. Hybrid emitter all back contact solar cell

    DOE Patents [OSTI]

    Loscutoff, Paul; Rim, Seung

    2016-04-12

    An all back contact solar cell has a hybrid emitter design. The solar cell has a thin dielectric layer formed on a backside surface of a single crystalline silicon substrate. One emitter of the solar cell is made of doped polycrystalline silicon that is formed on the thin dielectric layer. The other emitter of the solar cell is formed in the single crystalline silicon substrate and is made of doped single crystalline silicon. The solar cell includes contact holes that allow metal contacts to connect to corresponding emitters.

  12. Positron emitter labeled enzyme inhibitors

    DOE Patents [OSTI]

    Fowler, Joanna S.; MacGregor, Robert R.; Wolf, Alfred P.; Langstrom, Bengt

    1990-01-01

    This invention involves a new strategy for imaging and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide inactivators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography.

  13. Positron emitter labeled enzyme inhibitors

    DOE Patents [OSTI]

    Fowler, J.S.; MacGregor, R.R.; Wolf, A.P.

    1987-05-22

    This invention involved a new strategy for imaging and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide in activators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography. 2 figs.

  14. High current plasma electron emitter

    SciTech Connect (OSTI)

    Fiksel, G.; Almagri, A.F.; Craig, D.

    1995-07-01

    A high current plasma electron emitter based on a miniature plasma source has been developed. The emitting plasma is created by a pulsed high current gas discharge. The electron emission current is 1 kA at 300 V at the pulse duration of 10 ms. The prototype injector described in this paper will be used for a 20 kA electrostatic current injection experiment in the Madison Symmetric Torus (MST) reversed-field pinch. The source will be replicated in order to attain this total current requirement. The source has a simple design and has proven very reliable in operation. A high emission current, small size (3.7 cm in diameter), and low impurity generation make the source suitable for a variety of fusion and technological applications.

  15. Emittance and Phase Space Exchange (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Conference: Emittance and Phase Space Exchange Citation Details In-Document Search Title: Emittance and Phase Space Exchange Alternative chicane-type beam lines are proposed for ...

  16. Emittance and Phase Space Exchange (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Emittance and Phase Space Exchange Citation Details In-Document Search Title: Emittance and Phase Space Exchange You are accessing a document from the Department of Energy's ...

  17. Emittance and Phase Space Exchange for Advanced Beam Manipulation...

    Office of Scientific and Technical Information (OSTI)

    Emittance and Phase Space Exchange for Advanced Beam Manipulation and Diagnostics Citation Details In-Document Search Title: Emittance and Phase Space Exchange for Advanced Beam ...

  18. Emittance exchange results (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Conference: Emittance exchange results Citation Details In-Document Search Title: Emittance exchange results You are accessing a document from the Department of Energy's (DOE)...

  19. Emittance preservation during bunch compression with a magnetized beam

    SciTech Connect (OSTI)

    Stratakis, Diktys

    2015-09-02

    The deleterious effects of coherent synchrotron radiation (CSR) on the phase-space and energy spread of high-energy beams in accelerator light sources can significantly constrain the machine design and performance. In this paper, we present a simple method to preserve the beam emittance by means of using magnetized beams that exhibit a large aspect ratio on their transverse dimensions. The concept is based on combining a finite solenoid field where the beam is generated together with a special optics adapter. Numerical simulations of this new type of beam source show that the induced phase-space density growth can be notably suppressed to less than 1% for any bunch charge. This work elucidates the key parameters that are needed for emittance preservation, such as the required field and aspect ratio for a given bunch charge.

  20. Energy Department Intends to Issue Funding Opportunity Announcement for

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

    Clean Energy Manufacturing Innovation Institute | Department of Energy Intends to Issue Funding Opportunity Announcement for Clean Energy Manufacturing Innovation Institute Energy Department Intends to Issue Funding Opportunity Announcement for Clean Energy Manufacturing Innovation Institute May 20, 2016 - 11:14am Addthis The Office of Energy Efficiency and Renewable Energy (EERE) intends to issue, on behalf of the Advanced Manufacturing Office (AMO), a Funding Opportunity Announcement (FOA)

  1. Heterojunction solar cell with passivated emitter surface

    DOE Patents [OSTI]

    Olson, J.M.; Kurtz, S.R.

    1994-05-31

    A high-efficiency heterojunction solar cell is described wherein a thin emitter layer (preferably Ga[sub 0.52]In[sub 0.48]P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer. 1 fig.

  2. Heterojunction solar cell with passivated emitter surface

    DOE Patents [OSTI]

    Olson, Jerry M.; Kurtz, Sarah R.

    1994-01-01

    A high-efficiency heterojunction solar cell wherein a thin emitter layer (preferably Ga.sub.0.52 In.sub.0.48 P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer.

  3. Light modulated electron beam driven radiofrequency emitter

    DOE Patents [OSTI]

    Wilson, M.T.; Tallerico, P.J.

    1979-10-10

    The disclosure relates to a light modulated electron beam-driven radiofrequency emitter. Pulses of light impinge on a photoemissive device which generates an electron beam having the pulse characteristics of the light. The electron beam is accelerated through a radiofrequency resonator which produces radiofrequency emission in accordance with the electron, hence, the light pulses.

  4. Light modulated switches and radio frequency emitters

    DOE Patents [OSTI]

    Wilson, Mahlon T.; Tallerico, Paul J.

    1982-01-01

    The disclosure relates to a light modulated electron beam driven radiofrequency emitter. Pulses of light impinge on a photoemissive device which generates an electron beam having the pulse characteristics of the light. The electron beam is accelerated through a radiofrequency resonator which produces radiofrequency emission in accordance with the electron, hence, the light pulses.

  5. Emittance growth from electron beam modulation

    SciTech Connect (OSTI)

    Blaskiewicz, M.

    2009-12-01

    In linac ring colliders like MeRHIC and eRHIC a modulation of the electron bunch can lead to a modulation of the beam beam tune shift and steering errors. These modulations can lead to emittance growth. This note presents simple formulas to estimate these effects which generalize some previous results.

  6. An Observation of a Transverse to Longitudinal Emittance Exchange...

    Office of Scientific and Technical Information (OSTI)

    longitudinal emittance exchange (epsilonsub xsub in Leftrightarrow epsilonsub zsub out and epsilonsub zsub in Leftrightarrow epsilonsub xsub out) has...

  7. Longitudinal emittance measurements in the Booster and AGS during the 2014 RHIC gold run

    SciTech Connect (OSTI)

    Zeno, K.

    2014-08-18

    This note describes longitudinal emittance measurements that were made in the Booster and AGS during the 2014 RHIC Gold run. It also contains an overview of the longitudinal aspects of their setup during this run. Each bunch intended for RHIC is composed of beam from 4 Booster cycles, and there are two of them per AGS cycle. For each of the 8 Booster cycles required to produce the 2 bunches in the AGS, a beam pulse from EVIS is injected into the Booster and captured in four h=4 buckets. Then those bunches are accelerated to a porch where they are merged into 2 bunches and then into 1 bunch.

  8. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John

    2014-11-04

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  9. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John

    2012-07-17

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  10. Low Emittance Electron Gun for XFEL Application

    SciTech Connect (OSTI)

    Gough, C.; Paraliev, M.; Ivkovic, S.

    2009-08-04

    The Paul Scherrer Institute (PSI) in Switzerland is planning to build a cost-effective X-ray Free Electron Laser (XFEL) facility for 0.1-10 nm wavelength and 10-100 fsec pulse length, requiring only 6 GeV electron energy. The facility will consist of a Low Emittance electron Gun (LEG) with high gradient acceleration and advanced accelerator technology for preserving the emittance during acceleration and bunch compression. To demonstrate feasibility of the project, a 4 MeV test stand followed by a new 250 MeV test stand will be used at PSI. An emittance of <0.1 mm-mrad is desired, and this extreme value has prompted the development of several novel features: gated field emitting array, a pulsed high gradient gun, combined photo-field emission, pulsed solenoid focusing and a two-frequency cavity. The LEG should give stable emission of >200 pC, with >700 keV energy and >125 MV/m gradient.

  11. Emissivity Tuned Emitter for RTPV Power Sources

    SciTech Connect (OSTI)

    Carl M. Stoots; Robert C. O'Brien; Troy M. Howe

    2012-03-01

    Every mission launched by NASA to the outer planets has produced unexpected results. The Voyager I and II, Galileo, and Cassini missions produced images and collected scientific data that totally revolutionized our understanding of the solar system and the formation of the planetary systems. These missions were enabled by the use of nuclear power. Because of the distances from the Sun, electrical power was produced using the radioactive decay of a plutonium isotope. Radioisotopic Thermoelectric Generators (RTGs) used in the past and currently used Multi-Mission RTGs (MMRTGs) provide power for space missions. Unfortunately, RTGs rely on thermocouples to convert heat to electricity and are inherently inefficient ({approx} 3-7% thermal to electric efficiency). A Radioisotope Thermal Photovoltaic (RTPV) power source has the potential to reduce the specific mass of the onboard power supply by increasing the efficiency of thermal to electric conversion. In an RTPV, a radioisotope heats an emitter, which emits light to a photovoltaic (PV) cell, which converts the light into electricity. Developing an emitter tuned to the desired wavelength of the photovoltaic is a key part in increasing overall performance. Researchers at the NASA Glenn Research Center (GRC) have built a Thermal Photovoltaic (TPV) system, that utilizes a simulated General Purpose Heat Source (GPHS) from a MMRTG to heat a tantalum emitter. The GPHS is a block of graphite roughly 10 cm by 10 cm by 5 cm. A fully loaded GPHS produces 250 w of thermal power and weighs 1.6 kgs. The GRC system relies on the GPHS unit radiating at 1200 K to a tantalum emitter that, in turn, radiates light to a GaInAs photo-voltaic cell. The GRC claims system efficiency of conversion of 15%. The specific mass is around 167 kg/kWe. A RTPV power source that utilized a ceramic or ceramic-metal (cermet) matrix would allow for the combination of the heat source, canister, and emitter into one compact unit, and allow variation in size

  12. Multi-channel polarized thermal emitter

    DOE Patents [OSTI]

    Lee, Jae-Hwang; Ho, Kai-Ming; Constant, Kristen P

    2013-07-16

    A multi-channel polarized thermal emitter (PTE) is presented. The multi-channel PTE can emit polarized thermal radiation without using a polarizer at normal emergence. The multi-channel PTE consists of two layers of metallic gratings on a monolithic and homogeneous metallic plate. It can be fabricated by a low-cost soft lithography technique called two-polymer microtransfer molding. The spectral positions of the mid-infrared (MIR) radiation peaks can be tuned by changing the periodicity of the gratings and the spectral separation between peaks are tuned by changing the mutual angle between the orientations of the two gratings.

  13. An ultimate storage ring lattice with vertical emittance generated...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: An ultimate storage ring lattice with vertical emittance generated by damping wigglers Citation Details In-Document Search Title: An ultimate storage ring lattice...

  14. Preliminary Study on Emittance Growth in the LHEC Recirculating...

    Office of Scientific and Technical Information (OSTI)

    and synchrotron radiation (SR) fluctuations in the recirculating arcs. 6-D multi-particle tracking is launched to calculate the emittance from the statistical point of view. ...

  15. Space Charge Correction on Emittance Measurement of Low Energy...

    Office of Scientific and Technical Information (OSTI)

    of a charged particle beam through an accelerator and measure the emittance under the influence of space charge effects. We demonstrate the method of correctly calculating the...

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

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

    Linearly Polarized Thermal Emitter for More Efficient Thermophotovoltaic Devices Ames ... than can be used to create more efficient thermophotovoltaic devices for power generation. ...

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

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

    Laboratory researchers have developed fabrication methods for a polarized thermal emitter than can be used to create more efficient thermophotovoltaic devices for power generation. ...

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

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

    Thermophotovoltaic (TPV) devices can be used to generate power from photons, and consist of a thermal emitter ... contribute for electricity generation, which leads results in ...

  19. Muon Emittance Exchange with a Potato Slicer

    SciTech Connect (OSTI)

    Summers, D. J.; Hart, T. L.; Acosta, J. G.; Cremaldi, L. M.; Oliveros, S. J.; Perera, L. P.; Neuffer, D. V.

    2015-04-15

    We propose a novel scheme for final muon ionization cooling with quadrupole doublets followed by emittance exchange in vacuum to achieve the small beam sizes needed by a muon collider. A flat muon beam with a series of quadrupole doublet half cells appears to provide the strong focusing required for final cooling. Each quadrupole doublet has a low beta region occupied by a dense, low Z absorber. After final cooling, normalized transverse, longitudinal, and angular momentum emittances of 0.100, 2.5, and 0.200 mm-rad are exchanged into 0.025, 70, and 0.0 mm-rad. A skew quadrupole triplet transforms a round muon bunch with modest angular momentum into a flat bunch with no angular momentum. Thin electrostatic septa efficiently slice the flat bunch into 17 parts. The 17 bunches are interleaved into a 3.7 meter long train with RF deflector cavities. Snap bunch coalescence combines the muon bunch train longitudinally in a 21 GeV ring in 55 µs, one quarter of a synchrotron oscillation period. A linear long wavelength RF bucket gives each bunch a different energy causing the bunches to drift in the ring until they merge into one bunch and can be captured in a short wavelength RF bucket with a 13% muon decay loss and a packing fraction as high as 87 %.

  20. 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.

  1. Space-charge and emittance blowup in linacs

    SciTech Connect (OSTI)

    Jameson, R.A.

    1982-01-01

    Recent work leading to better understanding of beam emittance under space-charge conditions in linear transport and accelerating channels is reviewed. Some practical considerations are outlined for minimizing emittance growth by properly matching the input beam, including equipartitioning the energy balance, and by avoiding certain areas of tune-shift.

  2. Sharpening of field emitter tips using high-energy ions

    DOE Patents [OSTI]

    Musket, Ronald G.

    1999-11-30

    A process for sharpening arrays of field emitter tips of field emission cathodes, such as found in field-emission, flat-panel video displays. The process uses sputtering by high-energy (more than 30 keV) ions incident along or near the longitudinal axis of the field emitter to sharpen the emitter with a taper from the tip or top of the emitter down to the shank of the emitter. The process is particularly applicable to sharpening tips of emitters having cylindrical or similar (e.g., pyramidal) symmetry. The process will sharpen tips down to radii of less than 12 nm with an included angle of about 20 degrees. Because the ions are incident along or near the longitudinal axis of each emitter, the tips of gated arrays can be sharpened by high-energy ion beams rastered over the arrays using standard ion implantation equipment. While the process is particularly applicable for sharpening of arrays of field emitters in field-emission flat-panel displays, it can be effectively utilized in the fabrication of other vacuum microelectronic devices that rely on field emission of electrons.

  3. Plasma treatment for producing electron emitters

    DOE Patents [OSTI]

    Coates, Don Mayo; Walter, Kevin Carl

    2001-01-01

    Plasma treatment for producing carbonaceous field emission electron emitters is disclosed. A plasma of ions is generated in a closed chamber and used to surround the exposed surface of a carbonaceous material. A voltage is applied to an electrode that is in contact with the carbonaceous material. This voltage has a negative potential relative to a second electrode in the chamber and serves to accelerate the ions toward the carbonaceous material and provide an ion energy sufficient to etch the exposed surface of the carbonaceous material but not sufficient to result in the implantation of the ions within the carbonaceous material. Preferably, the ions used are those of an inert gas or an inert gas with a small amount of added nitrogen.

  4. New Low Emittance Lattice for the Super-B Accelerator

    SciTech Connect (OSTI)

    Biagini, M.E.; Boscolo, M.; Raimondi, P.; Tomassini, S.; Zobov, M.; Seeman, J.; Sullivan, M.; Wienands, U.; Wittmer, W.; Bettoni, S.; Paoloni, E.; Bogomyagkov, A.; Koop, I.; Levichev, E.; Nikitin, S.; Piminov, P.; Shatilov, D.; /Novosibirsk, IYF

    2011-10-21

    New low emittance lattices have been designed for the asymmetric SuperB accelerator, aiming at a luminosity of 10{sup 36} cm{sup -2} s{sup -1}. Main optics features are two alternating arc cells with different horizontal phase advance, decreasing beam emittance and allowing at the same time for easy chromaticity correction in the arcs. Emittance can be further reduced by a factor of two for luminosity upgrade. Spin rotation schemes for the e{sup -} beam have been studied to provide longitudinal polarization at the IP, and implementation into the lattice is in progress.

  5. Method and apparatus for multispray emitter for mass spectrometry

    DOE Patents [OSTI]

    Smith, Richard D.; Tang, Keqi; Lin, Yuehe

    2004-12-14

    A method and apparatus that utilizes two or more emitters simultaneously to form an electrospray of a sample that is then directed into a mass spectrometer, thereby increasing the total ion current introduced into an electrospray ionization mass spectrometer, given a liquid flow rate of a sample. The method and apparatus are most conveniently constructed as an array of spray emitters fabricated on a single chip, however, the present invention encompasses any apparatus wherein two or more emitters are simultaneously utilized to form an electrospray of a sample that is then directed into a mass spectrometer.

  6. Space Charge and Equilibrium Emittances in Damping Rings

    SciTech Connect (OSTI)

    Venturini, Marco; Oide, Katsunobu; Wolski, Andy

    2006-06-21

    We present a model of dynamics to account for the possible impact of space charge on the equilibrium emittances in storage rings and apply the model to study the current design of the International Linear Collider (ILC) damping rings.

  7. Absolute beam emittance measurements at RHIC using ionization profile monitors

    SciTech Connect (OSTI)

    Minty, M.; Connolly, R; Liu, C.; Summers, T.; Tepikian, S.

    2014-08-15

    In the past, comparisons between emittance measurements obtained using ionization profile monitors, Vernier scans (using as input the measured rates from the zero degree counters, or ZDCs), the polarimeters and the Schottky detectors evidenced significant variations of up to 100%. In this report we present studies of the RHIC ionization profile monitors (IPMs). After identifying and correcting for two systematic instrumental errors in the beam size measurements, we present experimental results showing that the remaining dominant error in beam emittance measurements at RHIC using the IPMs was imprecise knowledge of the local beta functions. After removal of the systematic errors and implementation of measured beta functions, precise emittance measurements result. Also, consistency between the emittances measured by the IPMs and those derived from the ZDCs was demonstrated.

  8. Non-blinking single-photon emitters in silica

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

    Rabouw, Freddy T.; Cogan, Nicole M. B.; Berends, Anne C.; Stam, Ward van der; Vanmaekelbergh, Daniel; Koenderink, A. Femius; Krauss, Todd D.; Donega, Celso de Mello

    2016-02-19

    Samples for single-emitter spectroscopy are usually prepared by spin-coating a dilute solution of emitters on a microscope cover slip of silicate based glass (such as quartz). Here, we show that both borosilicate glass and quartz contain intrinsic defect colour centres that fluoresce when excited at 532 nm. In a microscope image the defect emission is indistinguishable from spin-coated emitters. The emission spectrum is characterised by multiple peaks with the main peak between 2.05 and 2.20 eV, most likely due to coupling to a silica vibration with an energy that varies between 160 and 180 meV. The defects are single-photon emitters,more » do not blink, and have photoluminescence lifetimes of a few nanoseconds. Furthermore, photoluminescence from such defects may previously have been misinterpreted as originating from single nanocrystal quantum dots.« less

  9. Workshop in Novel Emitters and Nanostructured Materials | U.S...

    Office of Science (SC) Website

    Workshop in Novel Emitters and Nanostructured Materials Print Text Size: A A A Subscribe FeedbackShare Page The Solid-State Lighting Science Energy Frontier Research Center (SSLS ...

  10. FXR LIA Optimization - Time-resolved OTR Emittance Measurement

    SciTech Connect (OSTI)

    Jacob, J; Ong, M; Wargo, P; LeSage, G

    2005-07-21

    The Flash X-Ray Radiography (FXR) facility at Lawrence Livermore National Laboratory utilizes a high current, long pulse linear induction accelerator to produce high doses of x-ray radiation. Accurate characterization of the transverse beam emittance is required in order to facilitate accelerator modeling and tuning efforts and, ultimately, to optimize the final focus spot size, yielding higher resolution radiographs. In addition to conventional magnet scan, pepper-pot, and multiple screen techniques, optical transition radiation (OTR) has been proven as a useful emittance measurement diagnostic and is particularly well suited to the FXR accelerator. We shall discuss the time-resolved emittance characterization of an induction linac electron beam using OTR, and we will present our experimental apparatus and analysis software. We shall also develop the theoretical background of beam emittance and transition radiation.

  11. Space Charge Correction on Emittance Measurement of Low Energy...

    Office of Scientific and Technical Information (OSTI)

    in the calculation of beam emittance. We present below the preliminary results of a MATLAB code built to model the transport of a charged particle beam through an accelerator...

  12. Silicon Carbide Emitter Turn-Off Thyristor

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

    Wang, Jun; Wang, Gangyao; Li, Jun; Huang, Alex Q.; Melcher, Jerry; Atcitty, Stan

    2008-01-01

    A novel MOS-conmore » trolled SiC thyristor device, the SiC emitter turn-off thyristor (ETO) is a promising technology for future high-voltage switching applications because it integrates the excellent current conduction capability of a SiC thyristor with a simple MOS-control interface. Through unity-gain turn-off, the SiC ETO also achieves excellent Safe Operation Area (SOA) and faster switching speeds than silicon ETOs. The world's first 4.5-kV SiC ETO prototype shows a forward voltage drop of 4.26 V at 26.5  A / cm 2 current density at room and elevated temperatures. Tested in an inductive circuit with a 2.5 kV DC link voltage and a 9.56-A load current, the SiC ETO shows a fast turn-off time of 1.63 microseconds and a low 9.88 mJ turn-off energy. The low switching loss indicates that the SiC ETO could operate at about 4 kHz if 100  W / cm 2 conduction and the 100  W / cm 2 turn-off losses can be removed by the thermal management system. This frequency capability is about 4 times higher than 4.5-kV-class silicon power devices. The preliminary demonstration shows that the SiC ETO is a promising candidate for high-frequency, high-voltage power conversion applications, and additional developments to optimize the device for higher voltage (>5 kV) and higher frequency (10 kHz) are needed.« less

  13. Process for making a cesiated diamond film field emitter and field emitter formed therefrom

    DOE Patents [OSTI]

    Anderson, David F.; Kwan, Simon W.

    1999-01-01

    A process for making a cesiated diamond film comprises (a) depositing a quantity of cesium iodide on the diamond film in a vacuum of between about 10.sup.-4 Torr and about 10.sup.-7 Torr, (b) increasing the vacuum to at least about 10.sup.-8 Torr, and (c) imposing an electron beam upon the diamond film, said electron beam having an energy sufficient to dissociate said cesium iodide and to incorporate cesium into interstices of the diamond film. The cesiated diamond film prepared according to the process has an operating voltage that is reduced by a factor of at least approximately 2.5 relative to conventional, non-cesiated diamond film field emitters.

  14. Process for making a cesiated diamond film field emitter and field emitter formed therefrom

    DOE Patents [OSTI]

    Anderson, D.F.; Kwan, S.W.

    1999-03-30

    A process for making a cesiated diamond film comprises (a) depositing a quantity of cesium iodide on the diamond film in a vacuum of between about 10{sup {minus}4} Torr and about 10{sup {minus}7} Torr, (b) increasing the vacuum to at least about 10{sup {minus}8} Torr, and (c) imposing an electron beam upon the diamond film, said electron beam having an energy sufficient to dissociate said cesium iodide and to incorporate cesium into interstices of the diamond film. The cesiated diamond film prepared according to the process has an operating voltage that is reduced by a factor of at least approximately 2.5 relative to conventional, non-cesiated diamond film field emitters. 2 figs.

  15. Low Emittance Tuning Studies for SuperB

    SciTech Connect (OSTI)

    Liuzzo, Simone; Biagini, Maria; Raimondi, Pantaleo; Donald, Martin; /SLAC

    2012-07-06

    SuperB[1] is an international project for an asymmetric 2 rings collider at the B mesons cm energy to be built in the Rome area in Italy. The two rings will have very small beam sizes at the Interaction Point and very small emittances, similar to the Linear Collider Damping Rings ones. In particular, the ultra low vertical emittances, 7 pm in the LER and 4 pm in the HER, need a careful study of the misalignment errors effects on the machine performances. Studies on the closed orbit, vertical dispersion and coupling corrections have been carried out in order to specify the maximum allowed errors and to provide a procedure for emittance tuning. A new tool which combines MADX and Matlab routines has been developed, allowing for both corrections and tuning. Results of these studies are presented.

  16. Spring structure for a thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, Daniel T.

    1992-01-01

    A support is provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  17. Spring structure for a thermionic converter emitter support arrangement

    SciTech Connect (OSTI)

    Allen, D.T.

    1992-03-17

    A support is provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs. 7 figs.

  18. Excellent oxidation endurance of boron nitride nanotube field electron emitters

    SciTech Connect (OSTI)

    Song, Yenan; Song, Yoon-Ho; Milne, William I.; Jin Lee, Cheol

    2014-04-21

    Boron nitride nanotubes (BNNTs) are considered as a promising cold electron emission material owing to their negative electron affinity. BNNT field emitters show excellent oxidation endurance after high temperature thermal annealing of 600 °C in air ambient. There is no damage to the BNNTs after thermal annealing at a temperature of 600 °C and also no degradation of field emission properties. The thermally annealed BNNTs exhibit a high maximum emission current density of 8.39 mA/cm{sup 2} and show very robust emission stability. The BNNTs can be a promising emitter material for field emission devices under harsh oxygen environments.

  19. PARMELA simulation for BNL 704MHz SRF gun in low emittance operation...

    Office of Scientific and Technical Information (OSTI)

    PARMELA simulation for BNL 704MHz SRF gun in low emittance operation Citation Details In-Document Search Title: PARMELA simulation for BNL 704MHz SRF gun in low emittance operation ...

  20. Using antennas separated in flight direction to avoid effect of emitter clock drift in geolocation

    DOE Patents [OSTI]

    Ormesher, Richard C.; Bickel, Douglas L

    2012-10-23

    The location of a land-based radio frequency (RF) emitter is determined from an airborne platform. RF signaling is received from the RF emitter via first and second antennas. In response to the received RF signaling, signal samples for both antennas are produced and processed to determine the location of the RF emitter.

  1. A Resonant Cavity Approach to Non-Invasive, Pulse-to-Pulse EmittanceMeasurement

    SciTech Connect (OSTI)

    Kim, J.S.; Nantista, C.D.; Miller, R.H.; Weidemann, A.W.; /FARTECH, San Diego /SLAC

    2010-06-15

    We present a resonant cavity approach for non-invasive, pulse-to-pulse, beam emittance measurements of non-circular multi-bunch beams. In a resonant cavity, desired field components can be enhanced up to Q{sub L{lambda}}/{pi}, where Q{sub L{lambda}} is the loaded quality factor of the resonant mode {lambda}, when the cavity resonant mode matches the bunch frequency of a bunch-train beam pulse. In particular, a quad-cavity, with its quadrupole mode (TM{sub 220} for rectangular cavities) at beam operating frequency, rotated 45{sup o} with respect to the beamline, extracts the beam quadrupole moment exclusively, utilizing the symmetry of the cavity and some simple networks to suppress common modes. Six successive beam quadrupole moment measurements, performed at different betatron phases in a linear transport system determine the beam emittance, i.e. the beam size and shape in the beam's phase space, if the beam current and position at these points are known. In the presence of x-y beam coupling, ten measurements are required. One measurement alone provides the rms-beam size of a large aspect ratio beam. The resolution for such a measurement of rms-beam size with the rectangular quad-cavity monitor presented in this article is estimated to be on the order of ten microns. A prototype quad-cavity was fabricated and preliminary beam tests were performed at the Next Linear Collider Test Accelerator (NLCTA) at the Stanford Linear Accelerator Center (SLAC). Results were mainly limited by beam jitter and uncertainty in the beam position measurement at the cavity location. This motivated the development of a position-emittance integrated monitor.

  2. High-current lanthanum-hexaboride electron emitter for a quasi-stationary arc plasma generator

    SciTech Connect (OSTI)

    Davydenko, V. I. Ivanov, A. A. Shul’zhenko, G. I.

    2015-11-15

    A high-current electron emitter on the basis of lanthanum hexaboride is developed for quasi-stationary arc plasma generators of ion sources. The emitter consists of a set of LaB{sub 6} washers interleaved with washers made of thermally extended graphite. The emitter is heated by the current flowing through the graphite washers. The thermal regime of emitter operation during plasma generation is considered. The emitter has been successfully used in the ion sources of the diagnostic injectors of fast hydrogen atomic beams.

  3. Formation of shallow boron emitters in crystalline silicon using flash lamp annealing: Role of excess silicon interstitials

    SciTech Connect (OSTI)

    Riise, Heine Nygard Azarov, Alexander; Svensson, Bengt G.; Monakhov, Edouard

    2015-07-13

    Shallow, Boron (B)-doped p{sup +} emitters have been realized using spin-on deposition and Flash Lamp Annealing (FLA) to diffuse B into monocrystalline float zone Silicon (Si). The emitters extend between 50 and 140 nm in depth below the surface, have peak concentrations between 9 × 10{sup 19 }cm{sup –3} and 3 × 10{sup 20 }cm{sup –3}, and exhibit sheet resistances between 70 and 3000 Ω/□. An exceptionally large increase in B diffusion occurs for FLA energy densities exceeding ∼93 J/cm{sup 2} irrespective of 10 or 20 ms pulse duration. The effect is attributed to enhanced diffusion of B caused by Si interstitial injection following a thermally activated reaction between the spin-on diffusant film and the silicon wafer.

  4. Electrohydrodynamically driven large-area liquid ion sources

    DOE Patents [OSTI]

    Pregenzer, Arian L. (Corrales, NM)

    1988-01-01

    A large-area liquid ion source comprises means for generating, over a large area of the surface of a liquid, an electric field of a strength sufficient to induce emission of ions from a large area of said liquid. Large areas in this context are those distinct from emitting areas in unidimensional emitters.

  5. Electron Cloud at Low Emittance in CesrTA

    SciTech Connect (OSTI)

    Palmer, Mark; Alexander, James; Billing, Michael; Calvey, Joseph; Conolly, Christopher; Crittenden, James; Dobbins, John; Dugan, Gerald; Eggert, Nicholas; Fontes, Ernest; Forster, Michael; Gallagher, Richard; Gray, Steven; Greenwald, Shlomo; Hartill, Donald; Hopkins, Walter; Kreinick, David; Kreis, Benjamin; Leong, Zhidong; Li, Yulin; Liu, Xianghong; /more authors..

    2012-07-06

    The Cornell Electron Storage Ring (CESR) has been reconfigured as a test accelerator (CesrTA) for a program of electron cloud (EC) research at ultra low emittance. The instrumentation in the ring has been upgraded with local diagnostics for measurement of cloud density and with improved beam diagnostics for the characterization of both the low emittance performance and the beam dynamics of high intensity bunch trains interacting with the cloud. A range of EC mitigation methods have been deployed and tested and their effectiveness is discussed. Measurements of the electron cloud's effect on the beam under a range of conditions are discussed along with the simulations being used to quantitatively understand these results.

  6. Emittance Measurements of the SSRL Gun Test Facility

    SciTech Connect (OSTI)

    Hernandez, Michael; Clendenin, James; Fisher, Alan; Miller, Roger; Palmer, Dennis; Park, Sam; Schmerge, John; Weaver, Jim; Wiedemann, Helmut; Winick, Herman; Yeremian, Dian; Meyerhofer, David; Reis, David; /Rochester U.

    2011-09-01

    A photocathode RF gun test stand is under construction in the injector vault of the Stanford Synchrotron Radiation Laboratory at SLAC. The goal of this facility is to produce an electron beam with a normalized emittance of 1-3[mm-mr], a longitudinal bunch duration of the order of 10[ps] FWHM and approximately 1[nC] of charge per bunch. The beam will be generated from a laser driven copper photocathode RF gun developed in collaboration with BNL, LBL and UCLA. The 3-5[MeV] beam from the gun will be accelerated using a SLAC three meter S-band accelerator section. The emittance of the electron beam will be measured through the use of quadrupole scans with phosphor screens and also a wire scanner. The details of the experimental setup will be discussed, and first measurements will be presented and compared with results from PARMELA simulations.

  7. Transmission type flat-panel X-ray source using ZnO nanowire field emitters

    SciTech Connect (OSTI)

    Chen, Daokun; Song, Xiaomeng; Zhang, Zhipeng; Chen, Jun; Li, Ziping; She, Juncong; Deng, Shaozhi; Xu, Ningsheng

    2015-12-14

    A transmission type flat-panel X-ray source in diode structure was fabricated. Large-scale patterned ZnO nanowires grown on a glass substrate by thermal oxidation were utilized as field emitters, and tungsten thin film coated on silica glass was used as the transmission anode. Uniform distribution of X-ray generation was achieved, which benefited from the uniform electron emission from ZnO nanowires. Self-ballasting effect induced by the intrinsic resistance of ZnO nanowire and decreasing of screening effect caused by patterned emitters account for the uniform emission. Characteristic X-ray peaks of W-L lines and bremsstrahlung X-rays have been observed under anode voltages at a range of 18–20 kV, the latter of which were the dominant X-ray signals. High-resolution X-ray images with spatial resolution less than 25 μm were obtained by the flat-panel X-ray source. The high resolution was attributed to the small divergence angle of the emitted X-rays from the transmission X-ray source.

  8. Analysis of kicker noise induced beam emittance growth

    SciTech Connect (OSTI)

    Zhang W.; Sandberg, J.; Ahrens, L.; Blacker, I.M.; Brennan, M.; Blaskiewicz, M.; Fischer, W.; Hahn, H.; Huang, H.; Kling, N.; Lafky, M.; Marr, G.; Mernick, K.; Mi, J.; Minty, M.; Naylor, C.; Roser, T.; Shrey, T.; van Kuik, B.; Zelenski, A.

    2012-05-20

    Over the last few years, physicists have occasionally observed the presence of noise acting on the RHIC beams leading to emittance growth at high beam energies. While the noise was sporadic in the past, it became persistent during the Run-11 setup period. An investigation diagnosed the source as originating from the RHIC dump kicker system. Once identified the issue was quickly resolved. We report in this paper the investigation result, circuit analysis, measured and simulated waveforms, solutions, and future plans.

  9. Stochastic Boundary, Diffusion, Emittance Growth and Lifetime calculation for the RHIC e-lens

    SciTech Connect (OSTI)

    Abreu,N.P.; Fischer, W.; Luo, Y.; Robert-Demolaize, G.

    2009-01-20

    To compensate the large tune shift and tune spread generated by the head-on beam-beam interactions in polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), a low energy electron beam with proper Gaussian transverse profiles was proposed to collide head-on with the proton beam. In this article, using a modified version of SixTrack [1], we investigate stability of the single particle in the presence of head-on beam-beam compensation. The Lyapunov exponent and action diffusion are calculated and compared between the cases without and with beam-beam compensation for two different working points and various bunch intensities. Using the action diffusion results the emittance growth rate and lifetime of the proton beam is also estimated for the different scenarios.

  10. 4D Emittance Measurements Using Multiple Wire and Waist Scan Methods in the ATF Extraction Line

    SciTech Connect (OSTI)

    Rimbault, C.; Bambade, P.; Brossard, J.; Alabau, M.; Kuroda, S.; Scarfe, A.; Woodley, M.; /SLAC

    2011-11-02

    Emittance measurements performed in the diagnostic section of the Accelerator Test Facility (ATF) extraction line since 1998 led to vertical emittances three times larger than the expected ones, with a strong dependence on intensity. An experimental program is pursued to investigate potential sources of emittance growth and find possible remedies. This requires efficient and reliable emittance measurement techniques. In the past, several phase-space reconstruction methods developed at SLAC and KEK have been used to estimate the vertical emittance, based on multiple location beam size measurements and dedicated quadrupole scans. These methods have been shown to be very sensitive to measurement errors and other fluctuations in the beam conditions. In this context new emittance measurements have been performed revisiting these methods and newly developed ones with a systematic approach to compare and characterise their performance in the ATF extraction line.

  11. Radial arrays of nano-electrospray ionization emitters and methods of forming electrosprays

    DOE Patents [OSTI]

    Kelly, Ryan T [West Richland, WA; Tang, Keqi [Richland, WA; Smith, Richard D [Richland, WA

    2010-10-19

    Electrospray ionization emitter arrays, as well as methods for forming electrosprays, are described. The arrays are characterized by a radial configuration of three or more nano-electrospray ionization emitters without an extractor electrode. The methods are characterized by distributing fluid flow of the liquid sample among three or more nano-electrospray ionization emitters, forming an electrospray at outlets of the emitters without utilizing an extractor electrode, and directing the electrosprays into an entrance to a mass spectrometry device. Each of the nano-electrospray ionization emitters can have a discrete channel for fluid flow. The nano-electrospray ionization emitters are circularly arranged such that each is shielded substantially equally from an electrospray-inducing electric field.

  12. Recent progress on the self-aligned, selective-emitter silicon solar cell

    SciTech Connect (OSTI)

    Ruby, D.S.; Yang, P.; Roy, M.

    1997-10-01

    We developed a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignments to form self-aligned, patterned-emitter profiles. Standard commercial, screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. We succeeded in finding a set of parameters which resulted in good emitter uniformity and improved cell performance. We used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed, multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. Our initial results found a statistically significant improvement of half an absolute percentage point in cell efficiency when the self-aligned emitter etchback was combined with a 3-step PECVD-nitride surface passivation and hydrogenation treatment. 12 refs., 4 figs., 3 tabs.

  13. Effects of surface diffusion on high temperature selective emitters

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

    Peykov, Daniel; Yeng, Yi Xiang; Celanovic, Ivan; Joannopoulos, John D.; Schuh, Christopher A.

    2015-01-01

    Using morphological and optical simulations of 1D tantalum photonic crystals at 1200K, surface diffusion was determined to gradually reduce the efficiency of selective emitters. This was attributed to shifting resonance peaks and declining emissivity caused by changes to the cavity dimensions and the aperture width. Decreasing the structures curvature through larger periods and smaller cavity widths, as well as generating smoother transitions in curvature through the introduction of rounded cavities, was found to alleviate this degradation. An optimized structure, that shows both high efficiency selective emissivity and resistance to surface diffusion, was presented.

  14. Silicon solar cells made by a self-aligned, selective-emitter, plasma-etchback process

    DOE Patents [OSTI]

    Ruby, Douglas S.; Schubert, William K.; Gee, James M.

    1999-01-01

    A potentially low-cost process for forming and passivating a selective emitter. The process uses a plasma etch of the heavily doped emitter to improve its performance. The grids of the solar cell are used to mask the plasma etch so that only the emitter in the region between the grids is etched, while the region beneath the grids remains heavily doped for low contact resistance. This process is potentially low-cost because it requires no alignment. After the emitter etch, a silicon nitride layer is deposited by plasma-enhanced, chemical vapor deposition, and the solar cell is annealed in a forming gas.

  15. Optimization of the Dynamic Aperture for SPEAR3 Low-Emittance...

    Office of Scientific and Technical Information (OSTI)

    There is a smaller dynamic aperture for the lower emittance optics due to a stronger ... DAMPING; EFFICIENCY; GENETICS; LIFETIME; MAGNETS; OPTICS; OPTIMIZATION; RESONANCE

  16. Silicon solar cells made by a self-aligned, selective-emitter, plasma-etchback process

    DOE Patents [OSTI]

    Ruby, D.S.; Schubert, W.K.; Gee, J.M.

    1999-02-16

    A potentially low-cost process for forming and passivating a selective emitter. The process uses a plasma etch of the heavily doped emitter to improve its performance. The grids of the solar cell are used to mask the plasma etch so that only the emitter in the region between the grids is etched, while the region beneath the grids remains heavily doped for low contact resistance. This process is potentially low-cost because it requires no alignment. After the emitter etch, a silicon nitride layer is deposited by plasma-enhanced, chemical vapor deposition, and the solar cell is annealed in a forming gas. 5 figs.

  17. Final Muon Emittance Exchange in Vacuum for a Collider

    SciTech Connect (OSTI)

    Summers, Don; Acosta, John; Cremaldi, Lucien; Hart, Terry; Oliveros, Sandra; Perera, Lalith; Wu, Wanwei; Neuffer, David

    2015-05-07

    We outline a plan for final muon ionization cooling with quadrupole doublets focusing onto short absorbers followed by emittance exchange in vacuum to achieve the small transverse beam sizes needed by a muon collider. A flat muon beam with a series of quadrupole doublet half cells appears to provide the strong focusing required for final cooling. Each quadrupole doublet has a low β region occupied by a dense, low Z absorber. After final cooling, normalized xyz emittances of (0.071, 0.141, 2.4) mm-rad are exchanged into (0.025, 0.025, 70) mm-rad. Thin electrostatic septa efficiently slice the bunch into 17 parts. The 17 bunches are interleaved into a 3.7 meter long train with RF deflector cavities. Snap bunch coalescence combines the muon bunch train longitudinally in a 21 GeV ring in 55 μs, one quarter of a synchrotron oscillation period. A linear long wavelength RF bucket gives each bunch a different energy causing the bunches to drift until they merge into one bunch and can be captured in a short wavelength RF bucket with a 13% muon decay loss and a packing fraction as high as 87%.

  18. RADIOACTIVE POSITRON EMITTER PRODUCTION BY ENERGETIC ALPHA PARTICLES IN SOLAR FLARES

    SciTech Connect (OSTI)

    Murphy, R. J. [Code 7650, Naval Research Laboratory, Washington, DC 20375 (United States); Kozlovsky, B. [Tel Aviv University, Tel Aviv (Israel); Share, G. H., E-mail: murphy@ssd5.nrl.navy.mil, E-mail: benz@wise.tau.ac.il, E-mail: share@astro.umd.edu [University of Maryland, College Park, MD 20742 (United States)

    2015-01-01

    Measurements of the 0.511 MeV positron-annihilation line from solar flares are used to explore the flare process in general and ion acceleration in particular. In flares, positrons are produced primarily by the decay of radioactive positron-emitting isotopes resulting from nuclear interactions of flare-accelerated ions with ambient solar material. Kozlovsky et al. provided ion-energy-dependent production cross sections for 67 positron emitters evaluated from their threshold energies (some <1 MeV nucleon{sup 1}) to a GeV nucleon{sup 1}, incorporating them into a computer code for calculating positron-emitter production. Adequate cross-section measurements were available for proton reactions, but not for ?-particle reactions where only crude estimates were possible. Here we re-evaluate the ?-particle cross sections using new measurements and nuclear reaction codes. In typical large gamma-ray line flares, proton reactions dominate positron production, but ?-particle reactions will dominate for steeper accelerated-ion spectra because of their relatively low threshold energies. With the accelerated-{sup 3}He reactions added previously, the code is now reliable for calculating positron production from any distribution of accelerated-ion energies, not just those of typical flares. We have made the code available in the online version of the Journal. We investigate which reactions, projectiles, and ion energies contribute to positron production. We calculate ratios of the annihilation-line fluence to fluences of other gamma-ray lines. Such ratios can be used in interpreting flare data and in determining which nuclear radiation is most sensitive for revealing acceleration of low-energy ions at the Sun.

  19. Is transverse feedback necessary for the SSC emittance preservation? (Vibration noise analysis and feedback parameters optimization)

    SciTech Connect (OSTI)

    Parkhomchuk, V.V.; Shiltsev, V.D.

    1993-06-01

    The paper considers the Superconducting Super Collider (SSC) site ground motion measurements as well as data from accelerators worldwide about noises that worsen beam performance. Unacceptably fast emittance growth due to these noises is predicted for the SSC. A transverse feedback system was found to be the only satisfactory alternative to prevent emittance decay. Optimization of the primary feedback parameters was done.

  20. Emittance Studies of the BNL/SLAC/UCLA 1.6 Cell Photocathode RF Gun

    SciTech Connect (OSTI)

    Palmer, D.T.; Wang, X.J.; Miller, R.H.; Babzien, M.; Ben-Zvi, I.; Pellegrini, C.; Sheehan, J.; Skaritka, J.; Winick, H.; Woodle, M.; Yakimenko, V.; /Brookhaven

    2011-09-09

    The symmetrized 1.6 cell S-band photocathode gun developed by the BNL/SLAC/UCLA collaboration is in operation at the Brookhaven Accelerator Test Facility (ATF). A novel emittance compensation solenoid magnet has also been designed, built and is in operation at the ATF. These two subsystems form an emittance compensated photoinjector used for beam dynamics, advanced acceleration and free electron laser experiments at the ATF. The highest acceleration field achieved on the copper cathode is 150 MV/m, and the guns normal operating field is 130 MV/m. The maximum rf pulse length is 3 {mu}s. The transverse emittance of the photoelectron beam were measured for various injection parameters. The 1 nC emittance results are presented along with electron bunch length measurements that indicated that at above the 400 pC, space charge bunch lengthening is occurring. The thermal emittance, {epsilon}{sub o}, of the copper cathode has been measured.

  1. Emittance growth of an nonequilibrium intense electron beam in a transport channel with discrete focusing

    SciTech Connect (OSTI)

    Carlsten, B.E.

    1997-02-01

    The author analyzes the emittance growth mechanisms for a continuous, intense electron beam in a focusing transport channel, over distances short enough that the beam does not reach equilibrium. The emittance grows from the effect of nonlinear forces arising from (1) current density nonuniformities, (2) energy variations leading to nonlinearities in the space-charge force even if the current density is uniform, (3) axial variations in the radial vector potential, (4) an axial velocity shear along the beam, and (5) an energy redistribution of the beam as the beam compresses or expands. The emittance growth is studied analytically and numerically for the cases of balanced flow, tight focusing, and slight beam scalloping, and is additionally studied numerically for an existing 6-MeV induction linear accelerator. Rules for minimizing the emittance along a beamline are established. Some emittance growth will always occur, both from current density nonuniformities that arise along the transport and from beam radius changes along the transport.

  2. Quantum emitters dynamically coupled to a quantum field

    SciTech Connect (OSTI)

    Acevedo, O. L.; Quiroga, L.; Rodrguez, F. J.; Johnson, N. F.

    2013-12-04

    We study theoretically the dynamical response of a set of solid-state quantum emitters arbitrarily coupled to a single-mode microcavity system. Ramping the matter-field coupling strength in round trips, we quantify the hysteresis or irreversible quantum dynamics. The matter-field system is modeled as a finite-size Dicke model which has previously been used to describe equilibrium (including quantum phase transition) properties of systems such as quantum dots in a microcavity. Here we extend this model to address non-equilibrium situations. Analyzing the systems quantum fidelity, we find that the near-adiabatic regime exhibits the richest phenomena, with a strong asymmetry in the internal collective dynamics depending on which phase is chosen as the starting point. We also explore signatures of the crossing of the critical points on the radiation subsystem by monitoring its Wigner function; then, the subsystem can exhibit the emergence of non-classicality and complexity.

  3. Characterisation of the PXIE Allison-type emittance scanner

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

    D'Arcy, R.; Alvarez, M.; Gaynier, J.; Prost, L.; Scarpine, V.; Shemyakin, A.

    2016-01-26

    An Allison-type emittance scanner has been designed for PXIE at FNAL with the goal of providing fast and accurate phase space reconstruction. The device has been modified from previous LBNL/SNS designs to operate in both pulsed and DC modes with the addition of water-cooled front slits. Extensive calibration techniques and error analysis allowed confinement of uncertainty to the <5% level (with known caveats). With a 16-bit, 1 MHz electronics scheme the device is able to analyse a pulse with a resolution of 1 μs, allowing for analysis of neutralisation effects. As a result, this paper describes a detailed breakdown ofmore » the R&D, as well as post-run analysis techniques.« less

  4. Assessing the operational life of flexible printed boards intended for continuous flexing applications : a case study.

    SciTech Connect (OSTI)

    Beck, David Franklin

    2011-01-01

    Through the vehicle of a case study, this paper describes in detail how the guidance found in the suite of IPC (Association Connecting Electronics Industries) publications can be applied to develop a high level of design assurance that flexible printed boards intended for continuous flexing applications will satisfy specified lifetime requirements.

  5. z ? 1 Ly? emitters. I. The luminosity function , , ,

    SciTech Connect (OSTI)

    Wold, Isak G. B.; Barger, Amy J.; Cowie, Lennox L. E-mail: barger@astro.wisc.edu

    2014-03-10

    We construct a flux-limited sample of 135 candidate z ? 1 Ly? emitters (LAEs) from Galaxy Evolution Explorer (GALEX) grism data using a new data cube search method. These LAEs have luminosities comparable to those at high redshifts and lie within a 7 Gyr gap present in existing LAE samples. We use archival and newly obtained optical spectra to verify the UV redshifts of these LAEs. We use the combination of the GALEX UV spectra, optical spectra, and X-ray imaging data to estimate the active galactic nucleus (AGN) fraction and its dependence on Ly? luminosity. We remove the AGNs and compute the luminosity function (LF) from 60 z ? 1 LAE galaxies. We find that the best-fit LF implies a luminosity density increase by a factor of ?1.5 from z ? 0.3 to z ? 1 and ?20 from z ? 1 to z ? 2. We find a z ? 1 volumetric Ly? escape fraction of 0.7% 0.4%.

  6. On the Importance of Symmetrizing RF Coupler Fields for Low Emittance Beams

    SciTech Connect (OSTI)

    Li, Zenghai; Zhou, Feng; Vlieks, Arnold; Adolphsen, Chris; /SLAC

    2011-06-23

    The input power of accelerator structure is normally fed through a coupling slot(s) on the outer wall of the accelerator structure via magnetic coupling. While providing perfect matching, the coupling slots may produce non-axial-symmetric fields in the coupler cell that can induce emittance growth as the beam is accelerated in such a field. This effect is especially important for low emittance beams at low energies such as in the injector accelerators for light sources. In this paper, we present studies of multipole fields of different rf coupler designs and their effect on beam emittance for an X-band photocathode gun being jointly designed with LLNL, and X-band accelerator structures. We will present symmetrized rf coupler designs for these components to preserve the beam emittance.

  7. Characterizing and Optimizing Photocathode Laser Distributions for Ultra-low Emittance Electron Beam Operations

    SciTech Connect (OSTI)

    Zhou, F.; Bohler, D.; Ding, Y.; Gilevich, S.; Huang, Z.; Loos, H.; Ratner, D.; Vetter, S.

    2015-12-07

    Photocathode RF gun has been widely used for generation of high-brightness electron beams for many different applications. We found that the drive laser distributions in such RF guns play important roles in minimizing the electron beam emittance. Characterizing the laser distributions with measurable parameters and optimizing beam emittance versus the laser distribution parameters in both spatial and temporal directions are highly desired for high-brightness electron beam operation. In this paper, we report systematic measurements and simulations of emittance dependence on the measurable parameters represented for spatial and temporal laser distributions at the photocathode RF gun systems of Linac Coherent Light Source. The tolerable parameter ranges for photocathode drive laser distributions in both directions are presented for ultra-low emittance beam operations.

  8. Transverse Beam Emittance Measurements of a 16 MeV Linac at the Idaho Accelerator Center

    SciTech Connect (OSTI)

    S. Setiniyaz, T.A. Forest, K. Chouffani, Y. Kim, A. Freyberger

    2012-07-01

    A beam emittance measurement of the 16 MeV S-band High Repetition Rate Linac (HRRL) was performed at Idaho State University's Idaho Accelerator Center (IAC). The HRRL linac structure was upgraded beyond the capabilities of a typical medical linac so it can achieve a repetition rate of 1 kHz. Measurements of the HRRL transverse beam emittance are underway that will be used to optimize the production of positrons using HRRL's intense electron beam on a tungsten converter. In this paper, we describe a beam imaging system using on an OTR screen and a digital CCD camera, a MATLAB tool to extract beamsize and emittance, detailed measurement procedures, and the measured transverse emittances for an arbitrary beam energy of 15 MeV.

  9. Demonstration of cathode emittance dominated high bunch charge beams in a DC gun-based photoinjector

    SciTech Connect (OSTI)

    Gulliford, Colwyn Bartnik, Adam Bazarov, Ivan; Dunham, Bruce; Cultrera, Luca

    2015-03-02

    We present the results of transverse emittance and longitudinal current profile measurements of high bunch charge (≥100 pC) beams produced in the DC gun-based Cornell energy recovery linac photoinjector. In particular, we show that the cathode thermal and core beam emittances dominate the final 95% and core emittances measured at 9–9.5 MeV. Additionally, we demonstrate excellent agreement between optimized 3D space charge simulations and measurement, and show that the quality of the transverse laser distribution limits the optimal simulated and measured emittances. These results, previously thought achievable only with RF guns, demonstrate that DC gun based photoinjectors are capable of delivering beams with sufficient single bunch charge and beam quality suitable for many current and next generation accelerator projects such as Energy Recovery Linacs and Free Electron Lasers.

  10. Resonant tunneling device with two-dimensional quantum well emitter and base layers

    DOE Patents [OSTI]

    Simmons, J.A.; Sherwin, M.E.; Drummond, T.J.; Weckwerth, M.V.

    1998-10-20

    A double electron layer tunneling device is presented. Electrons tunnel from a two dimensional emitter layer to a two dimensional tunneling layer and continue traveling to a collector at a lower voltage. The emitter layer is interrupted by an isolation etch, a depletion gate, or an ion implant to prevent electrons from traveling from the source along the emitter to the drain. The collector is similarly interrupted by a backgate, an isolation etch, or an ion implant. When the device is used as a transistor, a control gate is added to control the allowed energy states of the emitter layer. The tunnel gate may be recessed to change the operating range of the device and allow for integrated complementary devices. Methods of forming the device are also set forth, utilizing epoxy-bond and stop etch (EBASE), pre-growth implantation of the backgate or post-growth implantation. 43 figs.

  11. Resonant tunneling device with two-dimensional quantum well emitter and base layers

    DOE Patents [OSTI]

    Simmons, Jerry A.; Sherwin, Marc E.; Drummond, Timothy J.; Weckwerth, Mark V.

    1998-01-01

    A double electron layer tunneling device is presented. Electrons tunnel from a two dimensional emitter layer to a two dimensional tunneling layer and continue traveling to a collector at a lower voltage. The emitter layer is interrupted by an isolation etch, a depletion gate, or an ion implant to prevent electrons from traveling from the source along the emitter to the drain. The collector is similarly interrupted by a backgate, an isolation etch, or an ion implant. When the device is used as a transistor, a control gate is added to control the allowed energy states of the emitter layer. The tunnel gate may be recessed to change the operating range of the device and allow for integrated complementary devices. Methods of forming the device are also set forth, utilizing epoxy-bond and stop etch (EBASE), pre-growth implantation of the backgate or post-growth implantation.

  12. Spontaneous radiation of a finite-size dipole emitter in hyperbolic media

    SciTech Connect (OSTI)

    Poddubny, Alexander N.; Belov, Pavel A.; Kivshar, Yuri S.

    2011-08-15

    We study the radiative decay and Purcell effect for a finite-size dipole emitter placed in a homogeneous uniaxial medium. We demonstrate that the radiative rate is strongly enhanced when the signs of the medium longitudinal and transverse dielectric constants are opposite, and that the isofrequency contour corresponds to a hyperbolic medium. We reveal that the Purcell enhancement factor remains finite even in the absence of losses and that it depends on the emitter size.

  13. Modeling the degradation of a metallic waste form intended for geologic disposal

    SciTech Connect (OSTI)

    Bauer, T.H.; Morris, E.E.

    2007-07-01

    Nuclear reactors operating with metallic fuels have led to development of robust metallic waste forms intended to immobilize hazardous constituents in oxidizing environments. Release data from a wide range of tests where small waste form samples have been immersed in a variety of oxidizing solutions have been analyzed and fit to a mechanistically-derived 'logarithmic growth' form for waste form degradation. A bounding model is described which plausibly extrapolates these fits to long-term degradation in a geologic repository. The resulting empirically-fit degradation model includes dependence on solution pH, temperature, and chloride concentration as well as plausible estimates of statistical uncertainty. (authors)

  14. Field emission behavior of carbon nanotube field emitters after high temperature thermal annealing

    SciTech Connect (OSTI)

    Sun, Yuning; Shin, Dong Hoon; Yun, Ki Nam; Leti, Guillaume; Hwang, Yeon Mo; Song, Yenan; Saito, Yahachi; Lee, Cheol Jin

    2014-07-15

    The carbon nanotube (CNT) field emitters have been fabricated by attaching a CNT film on a graphite rod using graphite adhesive material. The CNT field emitters showed much improved field emission properties due to increasing crystallinity and decreasing defects in CNTs after the high temperature thermal annealing at 900 °C in vacuum ambient. The CNT field emitters showed the low turn-on electric field of 1.15 V/μm, the low threshold electric field of 1.62 V/μm, and the high emission current of 5.9 mA which corresponds to a current density of 8.5 A/cm{sup 2}. In addition, the CNT field emitters indicated the enhanced field emission properties due to the multi-stage effect when the length of the graphite rod increases. The CNT field emitter showed good field emission stability after the high temperature thermal annealing. The CNT field emitter revealed a focused electron beam spot without any focusing electrodes and also showed good field emission repeatability.

  15. Improving the Sensitivity of Mass Spectrometry by Using a New Sheath Flow Electrospray Emitter Array at Subambient Pressures

    SciTech Connect (OSTI)

    Cox, Jonathan T.; Marginean, Ioan; Kelly, Ryan T.; Smith, Richard D.; Tang, Keqi

    2014-12-01

    Arrays of chemically etched emitters with individualized sheath gas capillaries have been developed to enhance electrospray ionization (ESI) at subambient pressures. By including an emitter array in a subambient pressure ionization with nanoelectrospray (SPIN) source, ionization and transmission efficiency can be maximized allowing for increased sensitivity in mass spectrometric analyses. The SPIN source eliminates the major ion losses at conventional ESI-mass spectrometry (MS) interface by placing the emitter in the first vacuum region of the instrument. To facilitate stable electrospray currents in such conditions we have developed an improved emitter array with individualized sheath gas around each emitter. The utility of the new emitter arrays for generating stable multi-electrosprays at subambient pressures was probed by coupling the emitter array/SPIN source with a time of flight (TOF) mass spectrometer. The instrument sensitivity was compared between single emitter/SPIN-MS and multi-emitter/SPIN-MS configurations using an equimolar solution of 9 peptides. An increase in sensitivity correlative to the number of emitters in the array was observed.

  16. Quantitative Single-Particle Digital Autoradiography with ?-Particle Emitters for Targeted Radionuclide Therapy using the iQID Camera

    SciTech Connect (OSTI)

    Miller, Brian W.; Frost, Sophia; Frayo, Shani; Kenoyer, Aimee L.; Santos, E. B.; Jones, Jon C.; Green, Damian J.; Hamlin, Donald K.; Wilbur, D. Scott; Fisher, Darrell R.; Orozco, Johnnie J.; Press, Oliver W.; Pagel, John M.; Sandmaier, B. M.

    2015-07-01

    Abstract Alpha emitting radionuclides exhibit a potential advantage for cancer treatments because they release large amounts of ionizing energy over a few cell diameters (5080 ?m) causing localized, irreparable double-strand DNA breaks that lead to cell death. Radioimmunotherapy (RIT) approaches using monoclonal antibodies labeled with alpha emitters may inactivate targeted cells with minimal radiation damage to surrounding tissues. For accurate dosimetry in alpha-RIT, tools are needed to visualize and quantify the radioactivity distribution and absorbed dose to targeted and non-targeted cells, especially for organs and tumors with heterogeneous radionuclide distributions. The aim of this study was to evaluate and characterize a novel single-particle digital autoradiography imager, iQID (ionizing-radiation Quantum Imaging Detector), for use in alpha-RIT experiments. Methods: The iQID camera is a scintillator-based radiation detection technology that images and identifies charged-particle and gamma-ray/X-ray emissions spatially and temporally on an event-by-event basis. It employs recent advances in CCD/CMOS cameras and computing hardware for real-time imaging and activity quantification of tissue sections, approaching cellular resolutions. In this work, we evaluated this systems characteristics for alpha particle imaging including measurements of spatial resolution and background count rates at various detector configurations and quantification of activity distributions. The technique was assessed for quantitative imaging of astatine-211 (211At) activity distributions in cryosections of murine and canine tissue samples. Results: The highest spatial resolution was measured at ~20 ?m full width at half maximum (FWHM) and the alpha particle background was measured at a rate of (2.6 0.5) 104 cpm/cm2 (40 mm diameter detector area). Simultaneous imaging of multiple tissue sections was performed using a large-area iQID configuration ( 11.5 cm). Estimation of the

  17. Optimization of oxidation processes to improve crystalline silicon solar cell emitters

    SciTech Connect (OSTI)

    Shen, L.; Liang, Z. C. Liu, C. F.; Long, T. J.; Wang, D. L.

    2014-02-15

    Control of the oxidation process is one key issue in producing high-quality emitters for crystalline silicon solar cells. In this paper, the oxidation parameters of pre-oxidation time, oxygen concentration during pre-oxidation and pre-deposition and drive-in time were optimized by using orthogonal experiments. By analyzing experimental measurements of short-circuit current, open circuit voltage, series resistance and solar cell efficiency in solar cells with different sheet resistances which were produced by using different diffusion processes, we inferred that an emitter with a sheet resistance of approximately 70 ?/? performed best under the existing standard solar cell process. Further investigations were conducted on emitters with sheet resistances of approximately 70 ?/? that were obtained from different preparation processes. The results indicate that emitters with surface phosphorus concentrations between 4.96 10{sup 20} cm{sup ?3} and 7.78 10{sup 20} cm{sup ?3} and with junction depths between 0.46 ?m and 0.55 ?m possessed the best quality. With no extra processing, the final preparation of the crystalline silicon solar cell efficiency can reach 18.41%, which is an increase of 0.4%{sub abs} compared to conventional emitters with 50 ?/? sheet resistance.

  18. Beam emittance measurements and simulations of injector line for radio frequency quadrupole

    SciTech Connect (OSTI)

    Mathew, Jose V. Rao, S. V. L. S.; Pande, Rajni; Singh, P.

    2015-07-15

    A 400 keV deuteron (D{sup +}) radio frequency quadrupole (RFQ) accelerator has been designed, built, and commissioned at the Bhabha Atomic Research Centre, India. A beam line has been developed for injecting deuterons into the 400 keV RFQ. This comprises of a RF plasma ion source and a low energy beam transport (LEBT) system, consisting of two solenoid magnets and two steerer magnets. The ion source is characterized in terms of transverse beam emittance. A slit-wire scanner based emittance measurement setup has been developed for the transverse emittance measurements of H{sup +} and D{sup +} beams. The measured emittance values are found to be well within the acceptance value for the RFQ. These measured emittance parameters are used to optimize the solenoid fields in LEBT to match the beam from the ion source to RFQ. TRACEWIN simulation code is used for the beam transport simulations. The simulations show 99% transmission of D{sup +} beam through the RFQ, while 95% transmission has been measured experimentally.

  19. Effect of the electrostatic plasma lens on the emittance of ahigh-current heavy ion beam

    SciTech Connect (OSTI)

    Chekh, Yu.; Goncharov, A.; Protsenko, I.; Brown, I.G.

    2004-01-10

    We describe measurements we have made of the emittance of a high-current, moderate-energy ion beam after transport through a permanent-magnet electrostatic plasma lens. The results indicate the absence of emittance growth due to the lens, when the lens is adjusted for optimal beam focusing. The measured emittance for a 16 keV Cu{sup 2+} ion beam formed by a vacuum arc ion source was about 0.4 {pi} {center_dot} mm {center_dot} mrad at a beam current of 50 mA rising more-or-less linearly to 1.5 {pi} {center_dot} mm {center_dot} mrad at 250 mA, and was conserved in beam transport through the lens. These results have significance for the application of high-current ion sources and the electrostatic plasma lens to particle accelerator injection.

  20. Emittance-Imposed Alignment and Frequency Tolerances for the TESLA Collider

    SciTech Connect (OSTI)

    Baboi, N

    2004-09-02

    One option in building a future 500 GeV c.m. linear collider is to use superconducting 1.3 GHz 9-cell cavities. However, wakefields excited by the bunch train in the TESLA (TeV-Energy Super Conducting Linear Accelerator) collider can resonantly drive the beam into unstable operation such that a BBU (Beam Break Up) mode results or at the very least significant emittance dilution occurs. The largest kick factors (proportional to the transverse fields which kick the beam off axis) are found in the first three dipole bands and hence multi-bunch emittance growth is mainly determined from these bands. These higher order dipole modes are damped by carefully orientating special couplers placed at both ends of the cavities. We investigate the dilution in the emittance of a beam with a random misalignment of cavities down the complete main linac. The beneficial effects of frequency errors on ameliorating the beam dilution are discussed.

  1. Effect of emitter parameter variation on the performance of heteroepitaxial indium phosphide solar cells

    SciTech Connect (OSTI)

    Jain, R.K.; Flood, D.J.

    1990-12-01

    Metallorganic chemical-vapor-deposited heteroepitaxial indium phosphide (InP) solar cell experimental results were simulated by using a PC-1D computer model. The effect of emitter parameter variation on the performance of n(+)/p/p(+) heteroepitaxial InP/GaAs solar cell was presented. The thinner and lighter doped emitters were observed to offer higher cell efficiencies. The influence of emitter thickness and minority carrier diffusion length on the cell efficiency with respect to dislocation density was studied. Heteroepitaxial cells with efficiencies similar to present day homojunction InP efficiencies (greater than 16 percent AMO) were shown to be attainable if a dislocation density lower than 10(exp 6)/sq cm could be achieved. A realistic optimized design study yielded InP solar cells of over 22 percent AMO efficiency at 25 C.

  2. Low emittance growth funneling line: preliminary design and beam dynamics study

    SciTech Connect (OSTI)

    Guy, F.W.

    1985-01-01

    A theoretical design study has resulted in a conceptual funneling-line design that has a transverse emittance growth limited to only 15% based on beam-dynamics calculations. Two 2-MeV, 100-mA proton beams are funneled from a two-channel, 212.5-MHz radio-frequency quadrupole (RFQ) to a single beam suitable for injection into a 425-MHz linac. The design uses permanent-magnet quadrupoles, dipoles, and combined-function elements. The low emittance growth is obtained by arranging the focusing strength, the periodic structure, and the bending elements so as to minimize abrupt changes in the beam environmental with consequent charge redistribution and space-charge-caused emittance growth.

  3. In-plane emission of indistinguishable photons generated by an integrated quantum emitter

    SciTech Connect (OSTI)

    Kalliakos, Sokratis Bennett, Anthony J.; Ward, Martin B.; Ellis, David J. P.; Skiba-Szymanska, Joanna; Shields, Andrew J.; Brody, Yarden; Schwagmann, Andre; Farrer, Ian; Griffiths, Jonathan P.; Jones, Geb A. C.; Ritchie, David A.

    2014-06-02

    We demonstrate the emission of indistinguishable photons along a semiconductor chip originating from carrier recombination in an InAs quantum dot. The emitter is integrated in the waveguiding region of a photonic crystal structure, allowing for on-chip light propagation. We perform a Hong-Ou-Mandel-type of experiment with photons collected from the exit of the waveguide, and we observe two-photon interference under continuous wave excitation. Our results pave the way for the integration of quantum emitters in advanced photonic quantum circuits.

  4. Electrostatic removal of lithium fluoride from field-emitter tips at elevated temperatures

    SciTech Connect (OSTI)

    Panitz, J.A. )

    1994-09-01

    The electrostatic removal of lithium fluoride (LiF) from field-emitter tips has been visualized at elevated temperatures in the transmission electron microscope (TEM). The apex of a field-emitter tip coated with [similar to]1500 A of LiF provides a unique substrate for observing the removal process in the TEM in real time, and its curvature generates the required electrostatic field strength. The influence of the imaging electron beam on coating morphology has been visually assessed. A LiF coating can tolerate an electron dose of [similar to]2000 [ital e][sup [minus

  5. Microelectrode for energy and current control of nanotip field electron emitters

    SciTech Connect (OSTI)

    Lüneburg, S.; Müller, M. Paarmann, A. Ernstorfer, R.

    2013-11-18

    Emerging experiments and applications in electron microscopy, holography, and diffraction benefit from miniaturized electron guns for compact experimental setups. We present a highly compact microelectrode integrated field emitter that consists of a tungsten nanotip coated with a few micrometers thick polyimide film followed by a several nanometers thick gold film, both positioned behind the exposed emitter apex by approximately 10–30 μm. The control of the electric field strength at the nanometer scale tip apex allows suppression, extraction, and energy tuning of field-emitted electrons. The performance of the microelectrode is demonstrated experimentally and supported by numerical simulations.

  6. Head Erosion with Emittance Growth in PWFA (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Conference: Head Erosion with Emittance Growth in PWFA Citation Details In-Document Search Title: Head Erosion with Emittance Growth in PWFA Authors: Li, S.Z. ; /SLAC ; Adli, E. ; /SLAC /U. Oslo ; England, R.J. ; Frederico, J. ; Gessner, S.J. ; Hogan, M.J. ; Litos, M.D. ; Walz, D.R. ; /SLAC ; Muggli, P. ; /Munich, Max Planck Inst. ; An, W. ; Clayton, C.E. ; Joshi, C. ; Lu, W. ; Marsh, K.A. ; Mori, W. ; Vafaei, N. more »; /UCLA « less Publication Date: 2012-08-08 OSTI Identifier: 1053431 Report

  7. Ultra-low emittance beam generation using two-color ionization injection in a CO2 laser-driven plasma accelerator

    SciTech Connect (OSTI)

    Schroeder, Carl; Benedetti, Carlo; Bulanov, Stepan; Chen, Min; Esarey, Eric; Geddes, Cameron; Vay, J.; Yu, Lule; Leemans, Wim

    2015-05-21

    Ultra-low emittance (tens of nm) beams can be generated in a plasma accelerator using ionization injection of electrons into a wakefield. An all-optical method of beam generation uses two laser pulses of different colors. A long-wavelength drive laser pulse (with a large ponderomotive force and small peak electric field) is used to excite a large wakefield without fully ionizing a gas, and a short-wavelength injection laser pulse (with a small ponderomotive force and large peak electric field), co-propagating and delayed with respect to the pump laser, to ionize a fraction of the remaining bound electrons at a trapped wake phase, generating an electron beam that is accelerated in the wake. The trapping condition, the ionized electron distribution, and the trapped bunch dynamics are discussed. Expressions for the beam transverse emittance, parallel and orthogonal to the ionization laser polarization, are presented. An example is shown using a 10-micron CO2 laser to drive the wake and a frequency-doubled Ti:Al2O3 laser for ionization injection.

  8. A new InGaP/GaAs tunneling heterostructure-emitter bipolar transistor (T-HEBT)

    SciTech Connect (OSTI)

    Tsai, Jung-Hui; Lee, Ching-Sung; Lour, Wen-Shiung; Ma, Yung-Chun; Ye, Sheng-Shiun

    2011-05-15

    Excellent characteristics of an InGaP/GaAs tunneling heterostructure-emitter bipolar transistor (T-HEBT) are first demonstrated. The insertion of a thin n-GaAs emitter layer between tynneling confinement and base layers effectivelty eliminates the potential spike at base-emitter junction and reduces the collector-emitter offset voltage, while the thin InGaP tunneling confinement layer is employed to reduce the transporting time across emitter region for electrons and maintain the good confinement effect for holes. Experimentally, the studied T-HEBN exhibits a maximum current gain of 285, a relatively low offset voltage of 40 mW, and a current-gain cutoff frequency of 26.4 GHz.

  9. Method or forming emitters for a back-contact solar cell

    DOE Patents [OSTI]

    Li, Bo; Cousins, Peter J.; Smith, David D.

    2014-08-12

    Methods of forming emitters for back-contact solar cells are described. In one embodiment, a method includes forming a first solid-state dopant source above a substrate. The first solid-state dopant source includes a plurality of regions separated by gaps. Regions of a second solid-state dopant source are formed above the substrate by printing.

  10. Method of forming emitters for a back-contact solar cell

    DOE Patents [OSTI]

    Li, Bo; Cousins, Peter J; Smith, David D

    2014-12-16

    Methods of forming emitters for back-contact solar cells are described. In one embodiment, a method includes forming a first solid-state dopant source above a substrate. The first solid-state dopant source includes a plurality of regions separated by gaps. Regions of a second solid-state dopant source are formed above the substrate by printing.

  11. Silicon cells made by self-aligned selective-emitter plasma-etchback process

    DOE Patents [OSTI]

    Ruby, Douglas S.; Schubert, William K.; Gee, James M.; Zaidi, Saleem H.

    2000-01-01

    Photovoltaic cells and methods for making them are disclosed wherein the metallized grids of the cells are used to mask portions of cell emitter regions to allow selective etching of phosphorus-doped emitter regions. The preferred etchant is SF.sub.6 or a combination of SF.sub.6 and O.sub.2. This self-aligned selective etching allows for enhanced blue response (versus cells with uniform heavy doping of the emitter) while preserving heavier doping in the region beneath the gridlines needed for low contact resistance. Embodiments are disclosed for making cells with or without textured surfaces. Optional steps include plasma hydrogenation and PECVD nitride deposition, each of which are suited to customized applications for requirements of given cells to be manufactured. The techniques disclosed could replace expensive and difficult alignment methodologies used to obtain selectively etched emitters, and they may be easily integrated with existing plasma processing methods and techniques of the invention may be accomplished in a single plasma-processing chamber.

  12. Reduction of Beam Emittance of Pep-X Using Quadruple Bend Achromat Cell

    SciTech Connect (OSTI)

    Wang, Min-Huey; Cai, Yunhai; Hettel, Robert; Nosochkov, Yuri; /SLAC

    2009-05-26

    SLAC National Accelerator Laboratory is studying an option of building a high brightness synchrotron light source machine, PEP-X, in the existing PEP-II tunnel [1, 2]. By replacing 6 arcs of FODO cells of PEPII High Energy Ring (HER) with two arcs of DBA and four arcs of TME and installation of 89.3 m long damping wiggler an ultra low beam emittance of 0.14 nm-rad (including intra-beam scattering) at 4.5 GeV is achieved. In this paper we study the possibility to further reduce the beam emittance by releasing the constraint of the dispersion free in the DBA straight. The QBA (Quadruple Bend Achromat) cell is used to replace the DBA. The ratio of outer and inner bending angle is optimized. The dispersion function in the non-dispersion straight is controlled to compromise with lower emittance and beam size at the dispersion straight. An undulator of period length 23 mm, maximum magnetic field of 1.053 T, and total periods of 150 is used to put in the 30 straights to simulate the effects of these IDs on the beam emittance and energy spread. The brightness including all the ID effects is calculated and compared to the original PEP-X design.

  13. Method of forming emitters for a back-contact solar cell

    SciTech Connect (OSTI)

    Li, Bo; Cousins, Peter J.; Smith, David D.

    2015-09-29

    Methods of forming emitters for back-contact solar cells are described. In one embodiment, a method includes forming a first solid-state dopant source above a substrate. The first solid-state dopant source includes a plurality of regions separated by gaps. Regions of a second solid-state dopant source are formed above the substrate by printing.

  14. 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.

  15. An Observation of a Transverse to Longitudinal Emittance Exchange at the Fermilab A0 Photoinjector

    SciTech Connect (OSTI)

    Koeth, Timothy W.

    2009-05-01

    An experimental program to perform a proof of principle of transverse to longitudinal emittance exchange ({epsilon}{sub x{sub in}} {Leftrightarrow} {epsilon}{sub z{sub out}} and {epsilon}{sub z{sub in}} {Leftrightarrow} {epsilon}{sub x{sub out}}) has been developed at the Fermilab A0 Photoinjector. A new beamline, including two magnetic dogleg channels and a TM{sub 110} deflecting mode radio frequency cavity, were constructed for the emittance exchange experiment. The first priority was a measurement of the Emittance Exchange beamline transport matrix. The method of difference orbits was used to measure the transport matrix. Through varying individual beam input vector elements, such as x{sub in}, x'{sub in}, y{sub in}, y'{sub in}, z{sub in}, or {delta}{sub in}, and measuring the changes in all of the beam output vector's elements, x{sub out}, x'{sub out}, y{sub out}, y'{sub out}, z{sub out}, {delta}{sub out}, the full 6 x 6 transport matrix was measured. The measured emittance exchange transport matrix was in overall good agreement with our calculated transport matrix. A direct observation of an emittance exchange was performed by measuring the electron beam's characteristics before and after the emittance exchange beamline. Operating with a 14.3 MeV, 250pC electron bunch, {epsilon}{sub z{sub in}} of 21.1 {+-} 1.5 mm{center_dot}mrad was observed to be exchanged with {epsilon}{sub x{sub out}} of 20.8 {+-} 2.00 mm{center_dot}mrad. Diagnostic limitations in the {epsilon}{sub z{sub out}} measurement did not account for an energy-time correlation, thus potentially returning values larger than the actual longitudinal emittance. The {epsilon}{sub x{sub in}} of 4.67 {+-} 0.22 mm{center_dot}mrad was observed to be exchanged with {epsilon}{sub z{sub out}} of 7.06 {+-} 0.43 mm{center_dot}mrad. The apparent {epsilon}{sub z{sub out}} growth is consistent with calculated values in which the correlation term is neglected.

  16. Assessment of the methane oxidation capacity of compacted soils intended for use as landfill cover materials

    SciTech Connect (OSTI)

    Rachor, Ingke; Gebert, Julia; Groengroeft, Alexander; Pfeiffer, Eva-Maria

    2011-05-15

    and diffusive ingress of atmospheric air. For one material with elevated levels of fine particles and high organic matter content, methane production impeded the quantification of methane oxidation potentials. Regarding the design of landfill cover layers it was concluded that the magnitude of the expected methane load, the texture and expected compaction of the cover material are key variables that need to be known. Based on these, a column study can serve as an appropriate testing system to determine the methane oxidation capacity of a soil intended as landfill cover material.

  17. Permanent Magnet Skew Quadrupoles for the Low Emittance LER Lattice of PEP-II

    SciTech Connect (OSTI)

    Decker, F.-J.; Anderson, S.; Kharakh, D.; Sullivan, M.; /SLAC

    2011-07-05

    The vertical emittance of the low energy ring (LER) in the PEP-II B-Factory was reduced by using skew quadrupoles consisting of permanent magnet material. The advantages over electric quadrupoles or rotating existing normal quadrupoles are discussed. To assure a high field quality, a Biot-Savart calculation was used to cancel the natural 12-pole component by using different size poles over a few layers. A magnetic measurement confirmed the high quality of the magnets. After installation and adjusting the original electric 12 skew and 16 normal quadrupoles the emittance contribution from the region close to the interaction point, which was the biggest part in the original design, was considerably reduced. To strengthen the vertical behavior of the LER beam, a low emittance lattice was developed. It lowered the original vertical design emittance from 0.54 nm-rad to 0.034 nm-rad. In order to achieve this, additional skew quadrupoles were required to bring the coupling correction out of the arcs and closer to the detector solenoid in the straight (Fig. 1). It is important, together with low vertical dispersion, that the low vertical emittance is not coupled into the horizontal, which is what we get if the coupling correction continues into the arcs. Further details of the lattice work is described in another paper; here we concentrate on the development of the permanent skew (PSK) quadrupole solution. Besides the permanent magnets there are two other possibilities, using electric magnets or rotating normal quadrupoles. Electric magnets would have required much more additional equipment like magnets stands, power supply, and new vacuum chamber sections. Rotating existing quadrupoles was also not feasible since they are mostly mounted together with a bending magnet on the same support girder.

  18. Limiting Effects in the Transverse-to-Longitudinal Emittance Exchange Technique for Low Energy Relativistic Electron Beams

    SciTech Connect (OSTI)

    Rihaoui, M.M.; Piot, P.; Power, J.G.; Gai, W.; /Argonne

    2009-05-01

    Transverse to longitudinal phase space manipulation hold great promises, e.g., as a potential technique for repartitioning the emittances of a beam. A proof-of-principle experiment to demonstrate the exchange of a low longitudinal emittance with a larger transverse emittance is in preparation at the Argonne Wakefield Accelerator using a {approx}12 MeV electron beam. In this paper we explore the limiting effects of this phase space manipulation method including high order and collective effects. A realistic start-to-end simulation of the planned proof-of-principle experiment including sensitivity studies is also presented.

  19. Fabrication of carbon nanotube emitters on the graphite rod and their high field emission performance

    SciTech Connect (OSTI)

    Sun, Yuning; Hoon Shin, Dong; Nam Yun, Ki; Song, Yenan; Saito, Yahachi; Jin Lee, Cheol

    2014-01-27

    Carbon nanotube (CNT) emitters with small emission area were fabricated on graphite rods using CNT films. By introducing the edge polishing process, the field emission performance of the CNT emitter was much improved, which showed a very high emission current of 6.34 mA (1.6 A/cm{sup 2}) under an applied electric field of 5.3 V/μm. It also indicates good long-term emission stability, which reveals no degradation in the emission current for 20 h. The emission patterns demonstrate uniform and well-focused electron beam spots. The enhanced field emission performance is mainly attributed to the suppressed edge emission after the edge polishing process.

  20. Highly efficient electroluminescence from a solution-processable thermally activated delayed fluorescence emitter

    SciTech Connect (OSTI)

    Wada, Yoshimasa; Kubo, Shosei; Suzuki, Katsuaki; Kaji, Hironori; Shizu, Katsuyuki; Tanaka, Hiroyuki; Adachi, Chihaya

    2015-11-02

    We developed a thermally activated delayed fluorescence (TADF) emitter, 2,4,6-tris(4-(9,9-dimethylacridan-10-yl)phenyl)-1,3,5-triazine (3ACR-TRZ), suitable for use in solution-processed organic light-emitting diodes (OLEDs). When doped into 4,4′-bis(carbazol-9-yl)biphenyl (CBP) host at 16 wt. %, 3ACR-TRZ showed a high photoluminescence quantum yield of 98%. Transient photoluminescence decay measurements of the 16 wt. % 3ACR-TRZ:CBP film confirmed that 3ACR-TRZ exhibits efficient TADF with a triplet-to-light conversion efficiency of 96%. This high conversion efficiency makes 3ACR-TRZ attractive as an emitting dopant in OLEDs. Using 3ACR-TRZ as an emitter, we fabricated a solution-processed OLED exhibiting a maximum external quantum efficiency of 18.6%.

  1. Studies and calculations of transverse emittance growth in high-energy proton storage rings

    SciTech Connect (OSTI)

    Mane, S.R.; Jackson, G.

    1989-03-01

    In the operation of proton-antiproton colliders, an important goal is to maximize the integrated luminosity. During such operations in the Fermilab Tevatron, the transverse beam emittances were observed to grow unexpectedly quickly, thus causing a serious reduction of the luminosity. We have studied this phenomenon experimentally and theoretically. A formula for the emittance growth rate, due to random dipole kicks, is derived. In the experiment, RF phase noise of known amplitude was deliberately injected into the Tevatron to kick the beam randomly, via dispersion at the RF cavities. Theory and experiment are found to agree reasonably well. We also briefly discuss the problem of quadrupole kicks. 14 refs., 2 figs., 3 tabs.

  2. Apparatus and method for improving radiation coherence and reducing beam emittance

    DOE Patents [OSTI]

    Csonka, Paul L.

    1992-01-01

    A method and apparatus for increasing the coherence and reducing the emittance of a beam-shaped pulse operates by splitting the pulse into multiple sub-beams, delaying the propagation of the various sub-beams by varying amounts, and then recombining the sub-beams by means of a rotating optical element to form a pulse of longer duration with improved transverse coherence.

  3. SU-E-J-03: A Comprehensive Comparison Between Alpha and Beta Emitters for Cancer Radioimmunotherapy

    SciTech Connect (OSTI)

    Huang, C.Y.; Guatelli, S; Oborn, B; Allen, B

    2014-06-01

    Purpose: The purpose of this study is to perform a comprehensive comparison of the therapeutic efficacy and cytotoxicity of alpha and beta emitters for Radioimmunotherapy (RIT). For each stage of cancer development, specific models were built for the separate objectives of RIT to be addressed:a) kill isolated cancer cells in transit in the lymphatic and vascular circulation,b) regress avascular cell clusters,c) regress tumor vasculature and tumors. Methods: Because of the nature of short range, high LET alpha and long energy beta radiation and heterogeneous antigen expression among cancer cells, the microdosimetric approach is essential for the RIT assessment. Geant4 based microdosimetric models are developed for the three different stages of cancer progression: cancer cells, cell clusters and tumors. The energy deposition, specific energy resulted from different source distribution in the three models was calculated separately for 4 alpha emitting radioisotopes ({sup 211}At, {sup 213}Bi, {sup 223}Ra and {sup 225}Ac) and 6 beta emitters ({sup 32}P, {sup 33}P, {sup 67}Cu, {sup 90}Y, {sup 131}I and {sup 177}Lu). The cell survival, therapeutic efficacy and cytotoxicity are determined and compared between alpha and beta emitters. Results: We show that internal targeted alpha radiation has advantages over beta radiation for killing isolated cancer cells, regressing small cell clusters and also solid tumors. Alpha particles have much higher dose specificity and potency than beta particles. They can deposit 3 logs more dose than beta emitters to single cells and solid tumor. Tumor control probability relies on deep penetration of radioisotopes to cancer cell clusters and solid tumors. Conclusion: The results of this study provide a quantitative understanding of the efficacy and cytotoxicity of RIT for each stage of cancer development.

  4. Analytical results from the quantum theory of a single-emitter nanolaser

    SciTech Connect (OSTI)

    Larionov, Nikolay V.; Kolobov, Mikhail I.

    2011-11-15

    We provide analytical results obtained in the framework of the quantum theory for a single-emitter nanolaser: an incoherently pumped single two-level system interacting with a single-cavity mode of finite finesse. In the good-cavity limit we analytically calculate the linewidth of such a laser, its amplitude fluctuation spectrum, and the intracavity Mandel Q parameter. Our analytical results are in very good agreement with numerical simulations of the master equation.

  5. Apparatus and method for improving radiation coherence and reducing beam emittance

    DOE Patents [OSTI]

    Csonka, P.L.

    1992-05-12

    A method and apparatus for increasing the coherence and reducing the emittance of a beam-shaped pulse operates by splitting the pulse into multiple sub-beams, delaying the propagation of the various sub-beams by varying amounts, and then recombining the sub-beams by means of a rotating optical element to form a pulse of longer duration with improved transverse coherence. 16 figs.

  6. Hollow cathode theory and experiment. II. A two-dimensional theoretical model of the emitter region

    SciTech Connect (OSTI)

    Mikellides, Ioannis G.; Katz, Ira; Goebel, Dan M.; Polk, James E.

    2005-12-01

    Despite their long history and wide range of applicability that includes electric propulsion, detailed understanding of the driving physics inside orificed hollow cathodes remains elusive. The theoretical complexity associated with the multicomponent fluid inside the cathode, and the difficulty of accessing empirically this region, have limited our ability to design cathodes that perform better and last longer. A two-dimensional axisymmetric theoretical model of the multispecies fluid inside an orificed hollow cathode is presented. The level of detail attained by the model is allowed by its extended system of governing equations not solved for in the past within the hollow cathode. Such detail is motivated in part by the need to quantify the effect(s) of the plasma on the emitter life, and by the need to build the foundation for future modeling that will assess erosion of the keeper plate. Results from numerical simulations of a 1.2-cm-diam cathode operating at a discharge current of 25 A and a gas flow rate of 5 SCCM show that approximately 10 A of electron current, and 3.45 A of ion current return back to the emitter surface. The total emitted electron current is 33.8 A and the peak emitter temperature is found to be 1440 K. Comparisons with the measurements suggest that anomalous heating of the plasma is possible near the orifice region. The model predicts heavy species temperatures as high as 2034 K and peak voltage drops near the emitting surface not exceeding 8 V.

  7. Elastomeric Microchip Electrospray Emitter for Stable Cone-Jet Mode Operation in the Nanoflow Regime.

    SciTech Connect (OSTI)

    Kelly, Ryan T.; Tang, Keqi; Irimia, Daniel; Toner, Mehmet; Smith, Richard D.

    2008-05-15

    Despite widespread interest in applying lab-on-a-chip technologies to mass spectrometry (MS)-based analyses, the coupling of microfluidics to electrospray ionization (ESI)-MS remains challenging. We report a robust, integrated poly(dimethylsiloxane) microchip interface for ESI-MS using simple and widely accessible microfabrication procedures. The interface uses an auxiliary channel to provide electrical contact in the Taylor cone of the electrospray without sample loss or dilution. The electric field at the channel terminus is enhanced by two vertical cuts that cause the interface to taper to a line rather than to a point, and the formation of small Taylor cones at the channel exit ensures sub-nL post-column dead volumes. While comparable ESI-MS sensitivities were achieved using both microchip and conventional fused silica capillary emitters, stable cone-jet mode electrospray could be established over a far broader range of flow rates (from 501000 nL/min) and applied potentials using the microchip emitters. This special feature of the microchip emitter should minimize the fine tuning required for electrospray optimization and make the stable electrospray more resistant to external perturbations.

  8. Formation of compressed flat electron beams with high transverse-emittance ratios

    SciTech Connect (OSTI)

    Zhu, J.; Piot, P.; Mihalcea, D.; Prokop, C. R.

    2014-08-01

    Flat beamsbeams with asymmetric transverse emittanceshave important applications in novel light-source concepts and advanced-acceleration schemes and could possibly alleviate the need for damping rings in lepton colliders. Over the last decade, a flat beam generation technique based on the conversion of an angular-momentum-dominated beam was proposed and experimentally tested. In this paper we explore the production of compressed flat beams. We especially investigate and optimize the flat beam transformation for beams with substantial fractional energy spread. We use as a simulation example the photoinjector of Fermilabs Advanced Superconducting Test Accelerator. The optimizations of the flat beam generation and compression at Advanced Superconducting Test Accelerator were done via start-to-end numerical simulations for bunch charges of 3.2 nC, 1.0 nC, and 20 pC at ?37??MeV. The optimized emittances of flat beams with different bunch charges were found to be 0.25???m (emittance ratio is ?400), 0.13????m, 15 nm before compression, and 0.41???m, 0.20???m, 16 nm after full compression, respectively, with peak currents as high as 5.5 kA for a 3.2?nC flat beam. These parameters are consistent with requirements needed to excite wakefields in asymmetric dielectric-lined waveguides or produce significant photon flux using small-gap micro-undulators.

  9. Intrinsic beam emittance of laser-accelerated electrons measured by x-ray spectroscopic imaging

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

    Golovin, G.; Banerjee, S.; Liu, C.; Chen, S.; Zhang, J.; Zhao, B.; Zhang, P.; Veale, M.; Wilson, M.; Seller, P.; et al

    2016-04-19

    Here, the recent combination of ultra-intense lasers and laser-accelerated electron beams is enabling the development of a new generation of compact x-ray light sources, the coherence of which depends directly on electron beam emittance. Although the emittance of accelerated electron beams can be low, it can grow due to the effects of space charge during free-space propagation. Direct experimental measurement of this important property is complicated by micron-scale beam sizes, and the presence of intense fields at the location where space charge acts. Reported here is a novel, non-destructive, single-shot method that overcame this problem. It employed an intense lasermore » probe pulse, and spectroscopic imaging of the inverse-Compton scattered x-rays, allowing measurement of an ultra-low value for the normalized transverse emittance, 0.15 (±0.06) π mm mrad, as well as study of its subsequent growth upon exiting the accelerator. The technique and results are critical for designing multi-stage laser-wakefield accelerators, and generating high-brightness, spatially coherent x-rays.« less

  10. Measurement of the tradeoff between intrinsic emittance and quantum efficiency from a NaKSb photocathode near threshold

    SciTech Connect (OSTI)

    Maxson, Jared Cultrera, Luca; Gulliford, Colwyn; Bazarov, Ivan

    2015-06-08

    We measure the tradeoff between the quantum efficiency and intrinsic emittance from a NaKSb photocathode at three increasing wavelengths (635, 650, and 690 nm) at or below the energy of the bandgap plus the electron affinity, hν≤E{sub g}+E{sub a}. These measurements were performed using a high voltage dc gun for varied photocathode surface fields of 1.4−4.4 MV/m. Measurements of intrinsic emittance are performed using two different methods and were found to agree. At the longest wavelength available, 690 nm, the intrinsic emittance was 0.26 μm/mm-rms with a quantum efficiency of ∼10{sup −4}. The suitability of NaKSb emitting at threshold for various low emittance applications is discussed.

  11. A generic formulation for emittance and lattice function evolution for non-Hamiltonian systems with stochastic effects

    SciTech Connect (OSTI)

    Berg, J. S.

    2015-05-03

    I describe a generic formulation for the evolution of emittances and lattice functions under arbitrary, possibly non-Hamiltonian, linear equations of motion. The average effect of stochastic processes, which would include ionization interactions and synchrotron radiation, is also included. I first compute the evolution of the covariance matrix, then the evolution of emittances and lattice functions from that. I examine the particular case of a cylindrically symmetric system, which is of particular interest for ionization cooling.

  12. Emittance measurements for optimum operation of the J-PARC RF-driven H{sup −} ion source

    SciTech Connect (OSTI)

    Ueno, A. Ohkoshi, K.; Ikegami, K.; Takagi, A.; Yamazaki, S.; Oguri, H.

    2015-04-08

    In order to satisfy the Japan Proton Accelerator Research Complex (J-PARC) second stage requirements of an H{sup −} ion beam of 60mA within normalized emittances of 1.5πmm•mrad both horizontally and vertically, a flat top beam duty factor of 1.25% (500μs×25Hz) and a life-time of longer than 1month, the J-PARC cesiated RF-driven H{sup −} ion source was developed by using an internal-antenna developed at the Spallation Neutron Source (SNS). The transverse emittances of the source were measured with various conditions to find out the optimum operation conditions minimizing the horizontal and vertical rms normalized emittances. The transverse emittances were most effectively reduced by operating the source with the plasma electrode temperature lower than 70°C. The optimum value of the cesium (Cs) density around the beam hole of the plasma electrode seems to be proportional to the plasma electrode temperature. The fine control of the Cs density is indispensable, since the emittances seem to increase proportionally to the excessiveness of the Cs density. Furthermore, the source should be operated with the Cs density beyond a threshold value, since the plasma meniscus shape and the ellipse parameters of the transverse emittances seem to be changed step-function-likely on the threshold Cs value.

  13. Quantitative single-particle digital autoradiography with α-particle emitters for targeted radionuclide therapy using the iQID camera

    SciTech Connect (OSTI)

    Miller, Brian W.; Frost, Sofia H. L.; Frayo, Shani L.; Kenoyer, Aimee L.; Santos, Erlinda; Jones, Jon C.; Orozco, Johnnie J.; Green, Damian J.; Press, Oliver W.; Pagel, John M.; Sandmaier, Brenda M.; Hamlin, Donald K.; Wilbur, D. Scott; Fisher, Darrell R.

    2015-07-15

    Purpose: Alpha-emitting radionuclides exhibit a potential advantage for cancer treatments because they release large amounts of ionizing energy over a few cell diameters (50–80 μm), causing localized, irreparable double-strand DNA breaks that lead to cell death. Radioimmunotherapy (RIT) approaches using monoclonal antibodies labeled with α emitters may thus inactivate targeted cells with minimal radiation damage to surrounding tissues. Tools are needed to visualize and quantify the radioactivity distribution and absorbed doses to targeted and nontargeted cells for accurate dosimetry of all treatment regimens utilizing α particles, including RIT and others (e.g., Ra-223), especially for organs and tumors with heterogeneous radionuclide distributions. The aim of this study was to evaluate and characterize a novel single-particle digital autoradiography imager, the ionizing-radiation quantum imaging detector (iQID) camera, for use in α-RIT experiments. Methods: The iQID camera is a scintillator-based radiation detection system that images and identifies charged-particle and gamma-ray/x-ray emissions spatially and temporally on an event-by-event basis. It employs CCD-CMOS cameras and high-performance computing hardware for real-time imaging and activity quantification of tissue sections, approaching cellular resolutions. In this work, the authors evaluated its characteristics for α-particle imaging, including measurements of intrinsic detector spatial resolutions and background count rates at various detector configurations and quantification of activity distributions. The technique was assessed for quantitative imaging of astatine-211 ({sup 211}At) activity distributions in cryosections of murine and canine tissue samples. Results: The highest spatial resolution was measured at ∼20 μm full width at half maximum and the α-particle background was measured at a rate as low as (2.6 ± 0.5) × 10{sup −4} cpm/cm{sup 2} (40 mm diameter detector area

  14. High temperature fuel/emitter system for advanced thermionic fuel elements

    SciTech Connect (OSTI)

    Moeller, Helen H.; Bremser, Albert H.; Gontar, Alexander; Fiviesky, Evgeny

    1997-01-10

    Specialists in space applications are currently focusing on bimodal power systems designed to provide both electric power and thermal propulsion (Kennedy, 1994 and Houts, 1995). Our work showed that thermionics is a viable technology for nuclear bimodal power systems. We demonstrated that materials for a thermionic fuel-emitter combination capable of performing at operating temperatures of 2473 K are not only possible but available. The objective of this work, funded by the US Department of Energy, Office of Space and Defense Power Systems, was to evaluate the compatibility of fuel material consisting of an uranium carbide/tantalum carbide solid solution with an emitter material consisting of a monocrystalline tungsten-niobium alloy. The uranium loading of the fuel material was 70 mole% uranium carbide. The program was successfully accomplished by a B and W/SIA LUTCH team. Its workscope was integrated with tasks being performed at both Babcock and Wilcox, Lynchburg Research Center, Lynchburg, Virginia, and SIA LUTCH, Podolsk, Russia. Samples were fabricated by LUTCH and seven thermal tests were performed in a hydrogen atmosphere. The first preliminary test was performed at 2273 K by LUTCH, and the remaining six tests were performed At B and W. Three tests were performed at 2273 K, two at 2373 K, and the final test at 2473 K. The results showed that the fuel and emitter materials were compatible in the presence of hydrogen. No evidence of liquid formation, dissolution of the uranium carbide from the uranium carbide/tantalum carbide solid solution, or diffusion of the uranium into the monocrystalline tungsten alloy was observed. Among the highlights of the program was the successful export of the fuel samples from Russia and their import into the US by commercial transport. This paper will discuss the technical aspects of this work.

  15. Ultra High p-doping Material Research for GaN Based Light Emitters

    SciTech Connect (OSTI)

    Vladimir Dmitriev

    2007-06-30

    The main goal of the Project is to investigate doping mechanisms in p-type GaN and AlGaN and controllably fabricate ultra high doped p-GaN materials and epitaxial structures. Highly doped p-type GaN-based materials with low electrical resistivity and abrupt doping profiles are of great importance for efficient light emitters for solid state lighting (SSL) applications. Cost-effective hydride vapor phase epitaxial (HVPE) technology was proposed to investigate and develop p-GaN materials for SSL. High p-type doping is required to improve (i) carrier injection efficiency in light emitting p-n junctions that will result in increasing of light emitting efficiency, (ii) current spreading in light emitting structures that will improve external quantum efficiency, and (iii) parameters of Ohmic contacts to reduce operating voltage and tolerate higher forward currents needed for the high output power operation of light emitters. Highly doped p-type GaN layers and AlGaN/GaN heterostructures with low electrical resistivity will lead to novel device and contact metallization designs for high-power high efficiency GaN-based light emitters. Overall, highly doped p-GaN is a key element to develop light emitting devices for the DOE SSL program. The project was focused on material research for highly doped p-type GaN materials and device structures for applications in high performance light emitters for general illumination P-GaN and p-AlGaN layers and multi-layer structures were grown by HVPE and investigated in terms of surface morphology and structure, doping concentrations and profiles, optical, electrical, and structural properties. Tasks of the project were successfully accomplished. Highly doped GaN materials with p-type conductivity were fabricated. As-grown GaN layers had concentration N{sub a}-N{sub d} as high as 3 x 10{sup 19} cm{sup -3}. Mechanisms of doping were investigated and results of material studies were reported at several International conferences providing

  16. Spontaneous decay rate of a dipole emitter in a strongly scattering disordered environment

    SciTech Connect (OSTI)

    Pierrat, R.; Carminati, R.

    2010-06-15

    We study the statistics of the fluorescence decay rate of a dipole emitter embedded in a strongly scattering medium. In the multiple-scattering regime, the probability of observing a decrease in the decay rate is substantial, as predicted by exact numerical simulations. The decrease originates from a reduction of the local density of optical states and is due to collective interactions and interferences. In the strong-scattering regime, signatures of recurrent scattering are visible in the behavior of the average decay rate.

  17. Flexible control of femtosecond pulse duration and separation using an emittance-spoiling foil in x-ray free-electron lasers

    SciTech Connect (OSTI)

    Ding, Y.; Behrens, C.; Coffee, R.; Decker, F. -J.; Emma, P.; Field, C.; Helml, W.; Huang, Z.; Krejcik, P.; Krzywinski, J.; Loos, H.; Lutman, A.; Marinelli, A.; Maxwell, T. J.; Turner, J.

    2015-06-22

    We report experimental studies of generating and controlling femtosecond x-ray pulses in free-electron lasers (FELs) using an emittance spoiling foil. By selectivity spoiling the transverse emittance of the electron beam, the output pulse duration or double-pulse separation is adjusted with a variable size single or double slotted foil. Measurements were performed with an X-band transverse deflector located downstream of the FEL undulator, from which both the FEL lasing and emittance spoiling effects are observed directly.

  18. Control of the external photoluminescent quantum yield of emitters coupled to nanoantenna phased arrays

    SciTech Connect (OSTI)

    Guo, Ke; Verschuuren, Marc A.; Lozano, Gabriel

    2015-08-21

    Optical losses in metals represent the largest limitation to the external quantum yield of emitters coupled to plasmonic antennas. These losses can be at the emission wavelength, but they can be more important at shorter wavelengths, i.e., at the excitation wavelength of the emitters, where the conductivity of metals is usually lower. We present accurate measurements of the absolute external photoluminescent quantum yield of a thin layer of emitting material deposited over a periodic nanoantenna phased array. Emission and absorptance measurements of the sample are performed using a custom-made setup including an integrating sphere and variable angle excitation. The measurements reveal a strong dependence of the external quantum yield on the angle at which the optical field excites the sample. Such behavior is attributed to the coupling between far-field illumination and near-field excitation mediated by the collective resonances supported by the array. Numerical simulations confirm that the inherent losses associated with the metal can be greatly reduced by selecting an optimum angle of illumination, which boosts the light conversion efficiency in the emitting layer. This combined experimental and numerical characterization of the emission from plasmonic arrays reveals the need to carefully design the illumination to achieve the maximum external quantum yield.

  19. The HETDEX pilot survey. V. The physical origin of Lyα emitters probed by near-infrared spectroscopy

    SciTech Connect (OSTI)

    Song, Mimi; Finkelstein, Steven L.; Gebhardt, Karl; Hill, Gary J.; Drory, Niv; Chonis, Taylor; Jogee, Shardha; Livermore, Rachael; Ashby, Matthew L. N.; Fazio, Giovanni G.; Huang, Jia-Sheng; Blanc, Guillermo A.; Bridge, Joanna; Ciardullo, Robin; Gronwall, Caryl; Hagen, Alex; Schneider, Donald P.; Fabricius, Maximilian; Gawiser, Eric; Salmon, Brett; and others

    2014-08-10

    We present the results from a Very Large Telescope/SINFONI and Keck/NIRSPEC near-infrared spectroscopic survey of 16 Lyα emitters (LAEs) at z = 2.1-2.5 in the COSMOS and GOODS-N fields discovered from the Hobby Eberly Telescope Dark Energy Experiment Pilot Survey. We detect rest-frame optical nebular lines (Hα and/or [O III] λ5007) for 10 of the LAEs and measure physical properties, including the star formation rate (SFR), gas-phase metallicity, gas mass fraction, and Lyα velocity offset. We find that LAEs may lie below the mass-metallicity relation for continuum-selected star-forming galaxies at the same redshift. The LAEs all show velocity shifts of Lyα relative to the systemic redshift ranging between +85 and +296 km s{sup –1} with a mean of +180 km s{sup –1}. This value is smaller than measured for continuum-selected star-forming galaxies at similar redshifts. The Lyα velocity offsets show a moderate correlation with the measured SFR (2.5σ), but no significant correlations are seen with the SFR surface density, specific SFR, stellar mass, or dynamical mass (≲1.5σ). Exploring the role of dust, kinematics of the interstellar medium (ISM), and geometry on the escape of Lyα photons, we find no signature of selective quenching of resonantly scattered Lyα photons. However, we also find no evidence that a clumpy ISM is enhancing the Lyα equivalent width. Our results suggest that the low metallicity in LAEs may be responsible for yielding an environment with a low neutral hydrogen column density and less dust, easing the escape of Lyα photons over that in continuum-selected star-forming galaxies.

  20. DISSECTION OF H{alpha} EMITTERS : LOW-z ANALOGS OF z > 4 STAR-FORMING GALAXIES

    SciTech Connect (OSTI)

    Shim, Hyunjin; Chary, Ranga-Ram

    2013-03-01

    Strong H{alpha} emitters (HAEs) dominate the z {approx} 4 Lyman-break galaxy (LBG) population. We have identified local analogs of these HAEs using the Sloan Digital Sky Survey. At z < 0.4, only 0.04% of the galaxies are classified as HAEs with H{alpha} equivalent widths ({approx}> 500 A) comparable to that of z {approx} 4 HAEs. Local HAEs have lower stellar mass and lower ultraviolet (UV) luminosity than z {approx} 4 HAEs, yet the H{alpha}-to-UV luminosity ratio, as well as their specific star formation rate, is consistent with that of z {approx} 4 HAEs, indicating that they are scaled-down versions of high-z star-forming galaxies. Compared to the previously studied local analogs of LBGs selected using rest-frame UV properties, local HAEs show similar UV luminosity surface density, weaker D{sub n} (4000) break, lower metallicity, and lower stellar mass. This implies that the local HAEs are less evolved galaxies than the traditional Lyman break analogs. In the stacked spectrum, local HAEs show a significant He II {lambda}4686 emission line suggesting a population of hot, massive stars similar to that seen in some Wolf-Rayet galaxies. Low [N II]/[O III] line flux ratios imply that local HAEs are inconsistent with being systems that host bright active galactic nuclei. Instead, it is highly likely that local HAEs are galaxies with an elevated ionization parameter, either due to a high electron density or large escape fraction of hydrogen ionizing photons as in the case of Wolf-Rayet galaxies.

  1. Large and stable emission current from synthesized carbon nanotube/fiber network

    SciTech Connect (OSTI)

    Di, Yunsong; Xiao, Mei; Zhang, Xiaobing Wang, Qilong; Li, Chen; Lei, Wei; Cui, Yunkang

    2014-02-14

    In order to obtain a large and stable electron field emission current, the carbon nanotubes have been synthesized on carbon fibers by cold wall chemical vapor deposition method. In the hierarchical nanostructures, carbon fibers are entangled together to form a conductive network, it could provide excellent electron transmission and adhesion property between electrode and emitters, dispersed clusters of carbon nanotubes with smaller diameters have been synthesized on the top of carbon fibers as field emitters, this kind of emitter distribution could alleviate electrostatic shielding effect and protect emitters from being wholly destroyed. Field emission properties of this kind of carbon nanotube/fiber network have been tested, up to 30?mA emission current at an applied electric field of 6.4?V/?m was emitted from as-prepared hierarchical nanostructures. Small current degradation at large emission current output by DC power operation indicated that carbon nanotube/fiber network could be a promising candidate for field emission electron source.

  2. The primary test of measuremental system for the actual emittance of relativistic electron beams

    SciTech Connect (OSTI)

    Liang Fu; Tai-bin Du; Xin Chen

    1995-12-31

    Recent, a new measuremental system has been established basically in Tsinghua University PRA. This system is able to measure the lower emittance of the electron beams from the RF accelerators for the FEL. It consists of a scanning magnetic field, a slit, a fluorescent screen, and a TV camera, an image processing system, a CAD 386 computer. Using it an actual phase diagram is obtained for 4-10 Mev electron beams, The principle and structure of the facility were reported in the Proceeding of the 15th FEL Conference. This paper describes the performance of the main components and the results of first measurement for the electron gun and 4Mev standing wave LINAC, Some new suggests are related too.

  3. HIGH AVERAGE CURRENT LOW EMITTANCE BEAM EMPLOYING CW NORMAL CONDUCTING GUN.

    SciTech Connect (OSTI)

    CHANG,X.; BEN-ZVI, I.; KEWISCH, J.; PAI, C.

    2007-06-25

    CW normal conducting guns usually do not achieve very high field gradient and waste much RF power at high field gradient compared to superconducting cavities. But they have less trapped modes and wakefields compared to the superconducting cavities due to their low Q. The external bucking coil can also be applied very close to the cathode to improve the beam quality. By using a low frequency gun with a recessed cathode and a carefully designed beam line we can get a high average current and a high quality beam with acceptable RF power loss on the cavity wall. This paper shows that the CW normal conducting gun can be a backup solution for those projects which need high peak and average current, low emittance electron beams such as the Relativistic Heavy Ion Collider (RHIC) e-cooling project and Energy Recovery Linac (Em) project.

  4. Improved efficiency of photoconductive THz emitters by increasing the effective contact length of electrodes

    SciTech Connect (OSTI)

    Singh, Abhishek; Surdi, Harshad; Nikesh, V. V.; Prabhu, S. S.; Döhler, G. H.

    2013-12-15

    We study the effect of a surface modification at the interface between metallic electrodes and semiconducting substrate in Semi-Insulating GaAs (SI-GaAs) based photoconductive emitters (PCE) on the emission of Tera-Hertz (THz) radiation. We partially etch out a 500 nm thick layer of SI-GaAs in grating like pattern with various periods before the contact deposition. By depositing the electrodes on the patterned surface, the electrodes follow the contour of the grating period. This increases the effective contact length of the electrodes per unit area of the active regions on the PCE. The maxima of the electric field amplitude of the THz pulses emitted from the patterned surface are enhanced by up to more than a factor 2 as compared to an un-patterned surface. We attribute this increase to the increase of the effective contact length of the electrode due to surface patterning.

  5. Studies of emittance growth and halo particle production in intense charged particle beams using the Paul Trap Simulator Experiment

    SciTech Connect (OSTI)

    Gilson, Erik P.; Davidson, Ronald C.; Dorf, Mikhail; Efthimion, Philip C.; Majeski, Richard; Chung, Moses; Gutierrez, Michael S.; Kabcenell, Aaron N.

    2010-05-15

    The Paul Trap Simulator Experiment (PTSX) is a compact laboratory experiment that places the physicist in the frame-of-reference of a long, charged-particle bunch coasting through a kilometers-long magnetic alternating-gradient (AG) transport system. The transverse dynamics of particles in both systems are described by the same set of equations, including nonlinear space-charge effects. The time-dependent voltages applied to the PTSX quadrupole electrodes in the laboratory frame are equivalent to the spatially periodic magnetic fields applied in the AG system. The transverse emittance of the charge bunch, which is a measure of the area in the transverse phase space that the beam distribution occupies, is an important metric of beam quality. Maintaining low emittance is an important goal when defining AG system tolerances and when designing AG systems to perform beam manipulations such as transverse beam compression. Results are reviewed from experiments in which white noise and colored noise of various amplitudes and durations have been applied to the PTSX electrodes. This noise is observed to drive continuous emittance growth and increase in root-mean-square beam radius over hundreds of lattice periods. Additional results are reviewed from experiments that determine the conditions necessary to adiabatically reduce the charge bunch's transverse size and simultaneously maintain high beam quality. During adiabatic transitions, there is no change in the transverse emittance. The transverse compression can be achieved either by a gradual change in the PTSX voltage waveform amplitude or frequency. Results are presented from experiments in which low emittance is achieved by using focusing-off-defocusing-off waveforms.

  6. LARGE BLOCK TEST STATUS REPORT

    SciTech Connect (OSTI)

    Wilder, D. G.; Blair, S. C.; Buscheck, T.; Carloson, R. C.; Lee, K.; Meike, A.; Ramirez, J. L.; Sevougian, D.

    1997-08-26

    This report is intended to serve as a status report, which essentially transmits the data that have been collected to date on the Large Block Test (LBT). The analyses of data will be performed during FY98, and then a complete report will be prepared. This status report includes introductory material that is not needed merely to transmit data but is available at this time and therefore included. As such, this status report will serve as the template for the future report, and the information is thus preserved. The United States Department of Energy (DOE) is investigatinq the suitability of Yucca Mountain (YM) as a potential site for the nation's first high-level nuclear waste repository. As shown in Fig. 1-1, the site is located about 120 km northwest of Las Vegas, Nevada, in an area of uninhabited desert.

  7. Lithography-free large-area metamaterials for stable thermophotovoltaic energy conversion

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

    Coppens, Zachary J.; Kravchenko, Ivan I.; Valentine, Jason G.

    2016-02-08

    A large-area metamaterial thermal emitter is fabricated using facile, lithography-free techniques. The device is composed of conductive oxides, refractory ceramics, and noble metals and shows stable, selective emission after exposure to 1173 K for 22 h in oxidizing and inert atmospheres. Lastly, the results indicate that the metamaterial can be used to achieve high-performance thermophotovoltaic devices for applications such as portable power generation.

  8. Investigating Enhanced Thorium Ionization in TIMS Using Re/Pt Porous Ion Emitters

    SciTech Connect (OSTI)

    Floyd E. Stanley III; K. J. Spencer; D. S. Schwartz; M. G. Watrous; J. E. Delmore

    2014-03-01

    Thermal ionization mass spectrometry (TIMS) is a widely used, benchmark method in the isotopic analysis of actinides relevant to various nuclear and geological fields. Despite significant previous use and inherent advantages, however, poor sample ionization continues to hamper the use of TIMS in the measurement of trace species; actinide ionization efficiencies frequently fall below 0.1 % using traditional instrument sources. Factors leading to poor ionization are compounded in the measurement of several highly refractory metals (e.g. U and Th) that may provide key signatures data in non-proliferation, safeguards and forensics efforts. Herein, a relatively new TIMS ion source strategy, employing porous ion emitters (PIEs) atop traditional filament assemblies, is investigated for the first time as a straightforward means of enhancing the ionization of Th, which is arguably a worst case scenario for TIMS-based actinide measurements. These sources yielded up to 410% greater Th sample utilization, relative to previously published values and in-house measurements collected using traditional methods. Accompanying scanning electron microscopy (SEM) investigations provide preliminary insight into possible mechanisms of PIE functioning and explore the impacts that extended heating have on the constructed source’s structure and composition.

  9. Ion emittance growth due to focusing modulation from slipping electron bunch

    SciTech Connect (OSTI)

    Wang, G.

    2015-02-17

    Low energy RHIC operation has to be operated at an energy ranging from γ = 4.1 to γ = 10. The energy variation causes the change of revolution frequency. While the rf system for the circulating ion will operate at an exact harmonic of the revolution frequency (h=60 for 4.5 MHz rf and h=360 for 28 MHz rf.), the superconducting rf system for the cooling electron beam does not have a frequency tuning range that is wide enough to cover the required changes of revolution frequency. As a result, electron bunches will sit at different locations along the ion bunch from turn to turn, i.e. the slipping of the electron bunch with respect to the circulating ion bunch. At cooling section, ions see a coherent focusing force due to the electrons’ space charge, which differs from turn to turn due to the slipping. We will try to estimate how this irregular focusing affects the transverse emittance of the ion bunch.

  10. Planar ultrananocrystalline diamond field emitter in accelerator radio frequency electron injector: Performance metrics

    SciTech Connect (OSTI)

    Baryshev, Sergey V. Antipov, Sergey; Jing, Chunguang; Qiu, Jiaqi; Shao, Jiahang; Liu, Wanming; Gai, Wei; Pérez Quintero, Kenneth J.; Sumant, Anirudha V.; Kanareykin, Alexei D.

    2014-11-17

    A case performance study of a planar field emission cathode (FEC) based on nitrogen-incorporated ultrananocrystalline diamond, (N)UNCD, was carried out in an RF 1.3 GHz electron gun. The FEC was a 100 nm (N)UNCD film grown on a 20 mm diameter stainless steel disk with a Mo buffer layer. At surface gradients 45–65 MV/m, peak currents of 1–80 mA (equivalent to 0.3–25 mA/cm{sup 2}) were achieved. Imaging with two YAG screens confirmed emission from the (N)UNCD surface with (1) the beam emittance of 1.5 mm × mrad/mm-rms and (2) longitudinal FWHM and rms widths of non-Gaussian energy spread of 0.7% and 11% at an electron energy of 2 MeV. Current stability was tested over the course of 36 × 10{sup 3} RF pulses (equivalent to 288 × 10{sup 6 }GHz oscillations)

  11. Generation of high power pulsed terahertz radiation using a plasmonic photoconductive emitter array with logarithmic spiral antennas

    SciTech Connect (OSTI)

    Berry, Christopher W.; Hashemi, Mohammad R.; Jarrahi, Mona

    2014-02-24

    An array of 3 × 3 plasmonic photoconductive terahertz emitters with logarithmic spiral antennas is fabricated on a low temperature (LT) grown GaAs substrate and characterized in response to a 200 fs optical pump from a Ti:sapphire mode-locked laser at 800 nm wavelength. A microlens array is used to split and focus the optical pump beam onto the active area of each plasmonic photoconductive emitter element. Pulsed terahertz radiation with record high power levels up to 1.9 mW in the 0.1–2 THz frequency range is measured at an optical pump power of 320 mW. The record high power pulsed terahertz radiation is enabled by the use of plasmonic contact electrodes, enhancing the photoconductor quantum efficiencies, and by increasing the overall device active area, mitigating the carrier screening effect and thermal breakdown at high optical pump power levels.

  12. The gas phase emitter effect of lanthanum within ceramic metal halide lamps and its dependence on the La vapor pressure and operating frequency

    SciTech Connect (OSTI)

    Ruhrmann, C.; Hoebing, T.; Bergner, A.; Groeger, S.; Awakowicz, P.; Mentel, J.; Denissen, C.; Suijker, J.

    2015-08-07

    The gas phase emitter effect increases the lamp lifetime by lowering the work function and, with it, the temperature of the tungsten electrodes of metal halide lamps especially for lamps in ceramic vessels due to their high rare earth pressures. It is generated by a monolayer on the electrode surface of electropositive atoms of certain emitter elements, which are inserted into the lamp bulb by metal iodide salts. They are vaporized, dissociated, ionized, and deposited by an emitter ion current onto the electrode surface within the cathodic phase of lamp operation with a switched-dc or ac-current. The gas phase emitter effect of La and the influence of Na on the emitter effect of La are studied by spatially and phase-resolved pyrometric measurements of the electrode tip temperature, La atom, and ion densities by optical emission spectroscopy as well as optical broadband absorption spectroscopy and arc attachment images by short time photography. An addition of Na to the lamp filling increases the La vapor pressure within the lamp considerably, resulting in an improved gas phase emitter effect of La. Furthermore, the La vapor pressure is raised by a heating of the cold spot. In this way, conditions depending on the La vapor pressure and operating frequency are identified, at which the temperature of the electrodes becomes a minimum.

  13. EXTREME CORONAL LINE EMITTERS: TIDAL DISRUPTION OF STARS BY MASSIVE BLACK HOLES IN GALACTIC NUCLEI?

    SciTech Connect (OSTI)

    Wang Tinggui; Zhou Hongyan; Wang Huiyuan; Yang Chenwei; Komossa, S.

    2012-04-20

    Tidal disruption of stars by supermassive black holes at the centers of galaxies is expected to produce unique emission-line signatures, which have not yet been explored adequately. Here we report the discovery of extremely strong coronal lines from [Fe X] up to [Fe XIV] in a sample of seven galaxies (including two recently reported cases), which we interpret as such signatures. This is the first systematic search for objects of this kind, by making use of the immense database of the Sloan Digital Sky Survey. The galaxies, which are non-active as evidenced by the narrow line ratios, show broad emission lines of complex profiles in more than half of the sample. Both the high-ionization coronal lines and the broad lines are fading on timescales of years in objects observed with spectroscopic follow-ups, suggesting their transient nature. Variations of inferred non-stellar continua, which have absolute magnitudes of at least -16 to -18 mag in the g band, are also detected in more than half of the sample. The coronal line emitters reside in sub-L{sub *} disk galaxies (-21.3 < M{sub i} < -18.5) with small stellar velocity dispersions. The sample seems to form two distinct types based on the presence or absence of the [Fe VII] lines, with the latter having relatively low luminosities of [O III], [Fe XI], and the host galaxies. These characteristics can most naturally be understood in the context of transient accretion onto intermediate-mass black holes at galactic centers following tidal disruption of stars in a gas-rich environment. We estimate the incidence of such events to be around 10{sup -5} yr{sup -1} for a galaxy with -21.3 < M{sub i} < -18.5.

  14. Constraining the Ly? escape fraction with far-infrared observations of Ly? emitters

    SciTech Connect (OSTI)

    Wardlow, Julie L.; Calanog, J.; Cooray, A.; Malhotra, S.; Zheng, Z.; Rhoads, J.; Finkelstein, S.; Bock, J.; Bridge, C.; Ciardullo, R.; Gronwall, C.; Conley, A.; Farrah, D.; Gawiser, E.; Heinis, S.; Ibar, E.; Ivison, R. J.; Marsden, G.; Oliver, S. J.; Riechers, D.; and others

    2014-05-20

    We study the far-infrared properties of 498 Ly? emitters (LAEs) at z = 2.8, 3.1, and 4.5 in the Extended Chandra Deep Field-South, using 250, 350, and 500 ?m data from the Herschel Multi-tiered Extragalactic Survey and 870 ?m data from the LABOCA ECDFS Submillimeter Survey. None of the 126, 280, or 92 LAEs at z = 2.8, 3.1, and 4.5, respectively, are individually detected in the far-infrared data. We use stacking to probe the average emission to deeper flux limits, reaching 1? depths of ?0.1 to 0.4 mJy. The LAEs are also undetected at ?3? in the stacks, although a 2.5? signal is observed at 870 ?m for the z = 2.8 sources. We consider a wide range of far-infrared spectral energy distributions (SEDs), including an M82 and an Sd galaxy template, to determine upper limits on the far-infrared luminosities and far-infrared-derived star formation rates of the LAEs. These star formation rates are then combined with those inferred from the Ly? and UV emission to determine lower limits on the LAEs' Ly? escape fraction (f {sub esc}(Ly?)). For the Sd SED template, the inferred LAEs f {sub esc}(Ly?) are ? 30% (1?) at z = 2.8, 3.1, and 4.5, which are all significantly higher than the global f {sub esc}(Ly?) at these redshifts. Thus, if the LAEs f {sub esc}(Ly?) follows the global evolution, then they have warmer far-infrared SEDs than the Sd galaxy template. The average and M82 SEDs produce lower limits on the LAE f {sub esc}(Ly?) of ?10%-20% (1?), all of which are slightly higher than the global evolution of f {sub esc}(Ly?), but consistent with it at the 2?-3? level.

  15. Large aperture diffractive space telescope

    DOE Patents [OSTI]

    Hyde, Roderick A.

    2001-01-01

    A large (10's of meters) aperture space telescope including two separate spacecraft--an optical primary objective lens functioning as a magnifying glass and an optical secondary functioning as an eyepiece. The spacecraft are spaced up to several kilometers apart with the eyepiece directly behind the magnifying glass "aiming" at an intended target with their relative orientation determining the optical axis of the telescope and hence the targets being observed. The objective lens includes a very large-aperture, very-thin-membrane, diffractive lens, e.g., a Fresnel lens, which intercepts incoming light over its full aperture and focuses it towards the eyepiece. The eyepiece has a much smaller, meter-scale aperture and is designed to move along the focal surface of the objective lens, gathering up the incoming light and converting it to high quality images. The positions of the two space craft are controlled both to maintain a good optical focus and to point at desired targets which may be either earth bound or celestial.

  16. EM reconstruction of dual isotope PET using staggered injections and prompt gamma positron emitters

    SciTech Connect (OSTI)

    Andreyev, Andriy; Sitek, Arkadiusz; Celler, Anna

    2014-02-15

    Purpose: The aim of dual isotope positron emission tomography (DIPET) is to create two separate images of two coinjected PET radiotracers. DIPET shortens the duration of the study, reduces patient discomfort, and produces perfectly coregistered images compared to the case when two radiotracers would be imaged independently (sequential PET studies). Reconstruction of data from such simultaneous acquisition of two PET radiotracers is difficult because positron decay of any isotope creates only 511 keV photons; therefore, the isotopes cannot be differentiated based on the detected energy. Methods: Recently, the authors have proposed a DIPET technique that uses a combination of radiotracer A which is a pure positron emitter (such as{sup 18}F or {sup 11}C) and radiotracer B in which positron decay is accompanied by the emission of a high-energy (HE) prompt gamma (such as {sup 38}K or {sup 60}Cu). Events that are detected as triple coincidences of HE gammas with the corresponding two 511 keV photons allow the authors to identify the lines-of-response (LORs) of isotope B. These LORs are used to separate the two intertwined distributions, using a dedicated image reconstruction algorithm. In this work the authors propose a new version of the DIPET EM-based reconstruction algorithm that allows the authors to include an additional, independent estimate of radiotracer A distribution which may be obtained if radioisotopes are administered using a staggered injections method. In this work the method is tested on simple simulations of static PET acquisitions. Results: The authors’ experiments performed using Monte-Carlo simulations with static acquisitions demonstrate that the combined method provides better results (crosstalk errors decrease by up to 50%) than the positron-gamma DIPET method or staggered injections alone. Conclusions: The authors demonstrate that the authors’ new EM algorithm which combines information from triple coincidences with prompt gammas and

  17. Single-Bunch Electron Cloud Effects in the GLC/NLC, US-Cold and TESLA Low Emittance Transport Lines

    SciTech Connect (OSTI)

    Bates, D.

    2005-04-12

    This paper examines the severity of the electron cloud effects in the Low Emittance Transport (LET) of linear colliders including the Bunch-Compressor System (BCS) and Beam Delivery System (BDS). We examine the electron cloud effects in the normal-conducting GLC/NLC or X-Band, and the super-conducting US-Cold and TESLA linear collider designs through the use of specially developed computer simulation codes. An estimate of the critical cloud density is given for the BDS and BCS of the X-Band collider.

  18. Control of focusing forces and emittances in plasma-based accelerators using near-hollow plasma channels

    SciTech Connect (OSTI)

    Schroeder, C. B.; Esarey, E.; Benedetti, C.; Leemans, W. P.

    2013-08-15

    A near-hollow plasma channel, where the plasma density in the channel is much less than the plasma density in the walls, is proposed to provide independent control over the focusing and accelerating forces in a plasma accelerator. In this geometry the low density in the channel contributes to the focusing forces, while the accelerating fields are determined by the high density in the channel walls. The channel also provides guiding for intense laser pulses used for wakefield excitation. Both electron and positron beams can be accelerated in a nearly symmetric fashion. Near-hollow plasma channels can effectively mitigate emittance growth due to Coulomb scattering for high-energy physics applications.

  19. Thermal Performance Evaluation of Attic Radiant Barrier Systems Using the Large Scale Climate Simulator (LSCS)

    SciTech Connect (OSTI)

    Shrestha, Som S; Miller, William A; Desjarlais, Andre Omer

    2013-01-01

    Application of radiant barriers and low-emittance surface coatings in residential building attics can significantly reduce conditioning loads from heat flow through attic floors. The roofing industry has been developing and using various radiant barrier systems and low-emittance surface coatings to increase energy efficiency in buildings; however, minimal data are available that quantifies the effectiveness of these technologies. This study evaluates performance of various attic radiant barrier systems under simulated summer daytime conditions and nighttime or low solar gain daytime winter conditions using the large scale climate simulator (LSCS). The four attic configurations that were evaluated are 1) no radiant barrier (control), 2) perforated low-e foil laminated oriented strand board (OSB) deck, 3) low-e foil stapled on rafters, and 4) liquid applied low-emittance coating on roof deck and rafters. All test attics used nominal RUS 13 h-ft2- F/Btu (RSI 2.29 m2-K/W) fiberglass batt insulation on attic floor. Results indicate that the three systems with radiant barriers had heat flows through the attic floor during summer daytime condition that were 33%, 50%, and 19% lower than the control, respectively.

  20. Nitrogen incorporated ultrananocrystalline diamond based field emitter array for a flat-panel x-ray source

    SciTech Connect (OSTI)

    Posada, Chrystian M.; Grant, Edwin J.; Lee, Hyoung K.; Castaño, Carlos H.; Divan, Ralu; Sumant, Anirudha V.; Rosenmann, Daniel; Stan, Liliana

    2014-04-07

    A field emission based flat-panel transmission x-ray source is being developed as an alternative for medical and industrial imaging. A field emitter array (FEA) prototype based on nitrogen incorporated ultrananocrystalline diamond film has been fabricated to be used as the electron source of this flat panel x-ray source. The FEA prototype was developed using conventional microfabrication techniques. The field emission characteristics of the FEA prototype were evaluated. Results indicated that emission current densities of the order of 6 mA/cm{sup 2} could be obtained at electric fields as low as 10 V/μm to 20 V/μm. During the prototype microfabrication process, issues such as delamination of the extraction gate and poor etching of the SiO{sub 2} insulating layer located between the emitters and the extraction layer were encountered. Consequently, alternative FEA designs were investigated. Experimental and simulation data from the first FEA prototype were compared and the results were used to evaluate the performance of alternative single and double gate designs that would yield better field emission characteristics compared to the first FEA prototype. The best simulation results are obtained for the double gate FEA design, when the diameter of the collimator gate is around 2.6 times the diameter of the extraction gate.

  1. Effect of increased crystallinity of single-walled carbon nanotubes used as field emitters on their electrical properties

    SciTech Connect (OSTI)

    Shimoi, Norihiro

    2015-12-07

    Single-walled carbon nanotubes (SWCNTs) synthesized by arc discharge are expected to exhibit good field emission (FE) properties at a low driving voltage. We used a coating containing homogeneously dispersed highly crystalline SWCNTs produced by a high-temperature annealing process to fabricate an FE device by a wet-coating process at a low cost. Using the coating, we succeeded in reducing the power consumption of field emitters for planar lighting devices. SWCNTs synthesized by arc discharge have crystal defects in the carbon network, which are considered to induce inelastic electron tunneling that deteriorates the electrical conductivity of the SWCNTs. In this study, the blocking of the transport of electrons in SWCNTs with crystal defects is simulated using an inelastic electron tunneling model. We succeeded in clarifying the mechanism underlying the electrical conductivity of SWCNTs by controlling their crystallinity. In addition, it was confirmed that field emitters using highly crystalline SWCNTs can lead to new applications operating with low power consumption and new devices that may change our daily lives in the future.

  2. PHOTOMETRIC PROPERTIES OF Ly{alpha} EMITTERS AT z {approx} 4.86 IN THE COSMOS 2 SQUARE DEGREE FIELD

    SciTech Connect (OSTI)

    Shioya, Y.; Taniguchi, Y.; Nagao, T.; Saito, T.; Trump, J.; Sasaki, S. S.; Ideue, Y.; Nakajima, A.; Matsuoka, K.; Murayama, T.; Scoville, N. Z.; Capak, P.; Ellis, R. S.; Sanders, D. B.; Kartaltepe, J.; Mobasher, B.; Aussel, H.; Koekemoer, A.; Carilli, C.; Garilli, B.

    2009-05-01

    We present results of a survey for Ly{alpha} emitters at z {approx} 4.86 based on optical narrowband ({lambda} {sub c} = 7126 A, {delta}{lambda} = 73 A) and broadband (B, V, r', i', and z') observations of the Cosmic Evolution Survey field using Suprime-Cam on the Subaru Telescope. We find 79 Ly{alpha} emitter (LAE) candidates at z {approx} 4.86 over a contiguous survey area of 1.83 deg{sup 2}, down to the Ly{alpha} line flux of 1.47 x 10{sup -17} erg s{sup -1} cm{sup -2}. We obtain the Ly{alpha} luminosity function with a best-fit Schechter parameters of log L* = 42.9{sup +0.5} {sub -0.3} erg s{sup -1} and {phi}* = 1.2{sup +8.0} {sub -1.1} x 10{sup -4} Mpc{sup -3} for {alpha} = -1.5 (fixed). The two-point correlation function for our LAE sample is {xi}(r) = (r/4.4{sup +5.7} {sub -2.9} Mpc){sup -1.90{+-}}{sup 0.22}. In order to investigate the field-to-field variations of the properties of Ly{alpha} emitters, we divide the survey area into nine tiles of 0.{sup 0}5 x 0.{sup 0}5 each. We find that the number density varies with a factor of {approx_equal}2 from field to field with high statistical significance. However, we find no significant field-to-field variance when we divide the field into four tiles with 0.{sup 0}7 x 0.{sup 0}7 each. We conclude that at least 0.5 deg{sup 2} survey area is required to derive averaged properties of LAEs at z {approx} 5, and our survey field is wide enough to overcome the cosmic variance.

  3. Monte Carlo calculated TG-60 dosimetry parameters for the {beta}{sup -} emitter {sup 153}Sm brachytherapy source

    SciTech Connect (OSTI)

    Sadeghi, Mahdi; Taghdiri, Fatemeh; Hamed Hosseini, S.; Tenreiro, Claudio

    2010-10-15

    Purpose: The formalism recommended by Task Group 60 (TG-60) of the American Association of Physicists in Medicine (AAPM) is applicable for {beta} sources. Radioactive biocompatible and biodegradable {sup 153}Sm glass seed without encapsulation is a {beta}{sup -} emitter radionuclide with a short half-life and delivers a high dose rate to the tumor in the millimeter range. This study presents the results of Monte Carlo calculations of the dosimetric parameters for the {sup 153}Sm brachytherapy source. Methods: Version 5 of the (MCNP) Monte Carlo radiation transport code was used to calculate two-dimensional dose distributions around the source. The dosimetric parameters of AAPM TG-60 recommendations including the reference dose rate, the radial dose function, the anisotropy function, and the one-dimensional anisotropy function were obtained. Results: The dose rate value at the reference point was estimated to be 9.21{+-}0.6 cGy h{sup -1} {mu}Ci{sup -1}. Due to the low energy beta emitted from {sup 153}Sm sources, the dose fall-off profile is sharper than the other beta emitter sources. The calculated dosimetric parameters in this study are compared to several beta and photon emitting seeds. Conclusions: The results show the advantage of the {sup 153}Sm source in comparison with the other sources because of the rapid dose fall-off of beta ray and high dose rate at the short distances of the seed. The results would be helpful in the development of the radioactive implants using {sup 153}Sm seeds for the brachytherapy treatment.

  4. Large displacement spherical joint

    DOE Patents [OSTI]

    Bieg, Lothar F.; Benavides, Gilbert L.

    2002-01-01

    A new class of spherical joints has a very large accessible full cone angle, a property which is beneficial for a wide range of applications. Despite the large cone angles, these joints move freely without singularities.

  5. Running Large Scale Jobs

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

    Running Large Scale Jobs Running Large Scale Jobs Users face various challenges with running and scaling large scale jobs on peta-scale production systems. For example, certain applications may not have enough memory per core, the default environment variables may need to be adjusted, or I/O dominates run time. This page lists some available programming and run time tuning options and tips users can try on their large scale applications on Hopper for better performance. Try different compilers

  6. Accelerated evolution of the Ly? luminosity function at z ? 7 revealed by the Subaru ultra-deep survey for Ly? emitters at z = 7.3

    SciTech Connect (OSTI)

    Konno, Akira; Ouchi, Masami; Ono, Yoshiaki; Shibuya, Takatoshi; Naito, Yoshiaki; Momose, Rieko; Yuma, Suraphong; Shimasaku, Kazuhiro; Nakajima, Kimihiko; Furusawa, Hisanori; Iye, Masanori

    2014-12-10

    We present the ultra-deep Subaru narrowband imaging survey for Ly? emitters (LAEs) at z = 7.3 in the Subaru/XMM-Newton Deep Survey (SXDS) and Cosmic Evolution Survey (COSMOS) fields (?0.5 deg{sup 2}) with a total integration time of 106 hr. Exploiting our new sharp bandwidth filter, NB101, installed on the Suprime-Cam, we have reached L(Ly?) = 2.4 10{sup 42} erg s{sup 1} (5?) for z = 7.3 LAEs, about four times deeper than previous Subaru z ? 7 studies, which allows us to reliably investigate the evolution of the Ly? luminosity function (LF) for the first time down to the luminosity limit same as those of Subaru z = 3.1-6.6 LAE samples. Surprisingly, we only find three and four LAEs in the SXDS and COSMOS fields, respectively, while one expects a total of ?65 LAEs by our survey in the case of no Ly? LF evolution from z = 6.6 to 7.3. We identify a decrease of the Ly? LF from z = 6.6 to 7.3 at the >90% confidence level from our z = 7.3 Ly? LF with the best-fit Schechter parameters of L{sub Ly?}{sup ?}=2.7{sub ?1.2}{sup +8.0}10{sup 42} erg s{sup ?1} and ?{sup ?}=3.7{sub ?3.3}{sup +17.6}10{sup ?4} Mpc{sup ?3} for a fixed ? = 1.5. Moreover, the evolution of the Ly? LF is clearly accelerated at z > 6.6 beyond the measurement uncertainties including cosmic variance. Because no such accelerated evolution of the UV-continuum LF or the cosmic star formation rate (SFR) is found at z ? 7, but suggested only at z > 8, this accelerated Ly? LF evolution is explained by physical mechanisms different from a pure SFR decrease but related to the Ly? production and escape in the process of cosmic reionization. Because a simple accelerating increase of intergalactic medium neutral hydrogen absorbing Ly? cannot be reconciled with Thomson scattering of optical depth measurements from WMAP and Planck, our findings may support new physical pictures suggested by recent theoretical studies, such as the existence of HI clumpy clouds within cosmic ionized bubbles that are selectively

  7. z {approx} 4 H{alpha} EMITTERS IN THE GREAT OBSERVATORIES ORIGINS DEEP SURVEY: TRACING THE DOMINANT MODE FOR GROWTH OF GALAXIES

    SciTech Connect (OSTI)

    Shim, Hyunjin; Chary, Ranga-Ram; Dickinson, Mark; Lin Lihwai; Yan, Chi-Hung; Spinrad, Hyron; Stern, Daniel

    2011-09-01

    We present evidence for strong H{alpha} emission in galaxies with spectroscopic redshifts in the range of 3.8 < z < 5.0 over the Great Observatories Origins Deep Survey fields. Among 74 galaxies detected in the Spitzer IRAC 3.6 and 4.5 {mu}m bands, more than 70% of the galaxies show clear excess at 3.6 {mu}m compared to the expected flux density from stellar continuum only. We provide evidence that this 3.6 {mu}m excess is due to H{alpha} emission redshifted into the 3.6 {mu}m band, and classify these 3.6 {mu}m excess galaxies to be H{alpha} emitter (HAE) candidates. The selection of HAE candidates using an excess in broadband filters is sensitive to objects whose rest-frame H{alpha} equivalent width (EW) is larger than 350 A. The H{alpha} inferred star formation rates (SFRs) of the HAEs range between 20 and 500 M{sub sun} yr{sup -1} and are a factor of {approx}6 larger than SFRs inferred from the UV continuum. The ratio between the H{alpha} luminosity and UV luminosity of HAEs is also on average larger than that of local starbursts. Possible reasons for such strong H{alpha} emission in these galaxies include different dust extinction properties, young stellar population ages, extended star formation histories, low metallicity, and a top-heavy stellar initial mass function. Although the correlation between UV slope {beta} and L{sub H{alpha}}/L{sub UV} raises the possibility that HAEs prefer a dust extinction curve which is steeper in the UV, the most dominant factor that results in strong H{alpha} emission appears to be star formation history. The H{alpha} EWs of HAEs are large despite their relatively old stellar population ages constrained by spectral energy distribution fitting, suggesting that at least 60% of HAEs produce stars at a constant rate. Under the assumption that the gas supply is sustained, HAEs are able to produce {approx}> 50% of the stellar mass density that is encompassed in massive (M{sub *} > 10{sup 11} M{sub sun}) galaxies at z {approx} 3

  8. Temperature dependence of photoluminescence properties in a thermally activated delayed fluorescence emitter

    SciTech Connect (OSTI)

    Niwa, Akitsugu; Kobayashi, Takashi Nagase, Takashi; Naito, Hiroyoshi; Goushi, Kenichi; Adachi, Chihaya

    2014-05-26

    Using steady-state and time-resolved photoluminescence (PL) spectroscopy, we have investigated the temperature dependence of PL properties of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyano-benzene (4CzIPN), which have a small energy gap between its singlet and triplet excited states and thus exhibits efficient thermally activated delayed fluorescence [H. Uoyama et al., Nature 492, 235 (2012)]. Below around 100?K, PL quantum efficiency of 4CzIPN thin films is largely suppressed and strong photoexcitation intensity dependence appears. These features can be explained by using rate equations for the densities of singlet and triplet excited states considering a triplet-triplet annihilation process.

  9. Room-temperature near-infrared silicon carbide nanocrystalline emitters based on optically aligned spin defects

    SciTech Connect (OSTI)

    Muzha, A.; Fuchs, F.; Simin, D.; Astakhov, G. V.; Tarakina, N. V.; Trupke, M.; Soltamov, V. A.; Mokhov, E. N.; Baranov, P. G.; Dyakonov, V.; and others

    2014-12-15

    Bulk silicon carbide (SiC) is a very promising material system for bio-applications and quantum sensing. However, its optical activity lies beyond the near infrared spectral window for in-vivo imaging and fiber communications due to a large forbidden energy gap. Here, we report the fabrication of SiC nanocrystals and isolation of different nanocrystal fractions ranged from 600?nm down to 60?nm in size. The structural analysis reveals further fragmentation of the smallest nanocrystals into ca. 10-nm-size clusters of high crystalline quality, separated by amorphization areas. We use neutron irradiation to create silicon vacancies, demonstrating near infrared photoluminescence. Finally, we detect room-temperature spin resonances of these silicon vacancies hosted in SiC nanocrystals. This opens intriguing perspectives to use them not only as in-vivo luminescent markers but also as magnetic field and temperature sensors, allowing for monitoring various physical, chemical, and biological processes.

  10. Running Large Scale Jobs

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

    try on their large scale applications on Hopper for better performance. Try different compilers and compiler options The available compilers on Hopper are PGI, Cray, Intel, GNU,...

  11. Novel Approaches to High-Efficiency III-V Nitride Heterostructure Emitters for Next-Generation Lighting Applications

    SciTech Connect (OSTI)

    Russell D. Dupuis

    2004-09-30

    We report research activities and technical progress on the development of high-efficiency long wavelength ({lambda} {approx} 540nm) green light emitting diodes which covers the first year of the three-year program ''Novel approaches to high-efficiency III-V nitride heterostructure emitters for next-generation lighting applications''. The first year activities were focused on the installation, set-up, and use of advanced equipment for the metalorganic chemical vapor deposition growth of III-nitride films and the characterization of these materials (Task 1) and the design, fabrication, testing of nitride LEDs (Task 4). As a progress highlight, we obtained improved quality of {approx} 2 {micro}m-thick GaN layers (as measured by the full width at half maximum of the asymmetric (102) X-ray diffraction peak of less than 350 arc-s) and higher p-GaN:Mg doping level (free hole carrier higher than 1E18 cm{sup -3}). Also in this year, we have developed the growth of InGaN/GaN active layers for long-wavelength green light emitting diodes, specifically, for emission at {lambda} {approx} 540nm. The effect of the Column III precursor (for Ga) and the post-growth thermal annealing effect were also studied. Our LED device fabrication process was developed and initially optimized, especially for low-resistance ohmic contacts for p-GaN:Mg layers, and blue-green light emitting diode structures were processed and characterized.

  12. THE QUASAR SDSS J153636.22+044127.0: A DOUBLE-PEAKED EMITTER IN A CANDIDATE BINARY BLACK HOLE SYSTEM

    SciTech Connect (OSTI)

    Tang Sumin; Grindlay, Jonathan

    2009-10-20

    Double-peaked emission lines are believed to be originated from accretion disks around supermassive black holes (SMBHs), and about 3% of z < 0.33 active galactic nuclei (AGNs) are found to be double-peaked emitters. The quasar SDSS J153636.22+044127.0 has recently been identified with peculiar broad-line emission systems exhibiting multiple redshifts. We decompose the Halpha and Hbeta profiles into a circular Keplerian disk-line component and other Gaussian components. We propose that the system is both a double-peaked emitter and a binary SMBH system, where the extra flux in the blue peaks of the broad lines comes from the region around the secondary black hole. We suggest that such black hole binary systems might also exist in many known double-peaked emitters, where the tidal torques from the secondary black hole clear the outer region of the disk around the primary black hole, similar to the gap in a protostellar disk due to the process of planetary migration, and might also stimulate the formation of a vertical extended source in the inner region around the primary which illuminates the disk. However, most secondary SMBHs in such systems might be too small to maintain a detectable broad-line region (BLR), so that the disk line from the primary dominates.

  13. Large Customers (DR Sellers)

    SciTech Connect (OSTI)

    Kiliccot, Sila

    2011-10-25

    State of the large customers for demand response integration of solar and wind into electric grid; openADR; CAISO; DR as a pseudo generation; commercial and industrial DR strategies; California regulations

  14. DETECTIONS OF FAINT Ly{alpha} EMITTERS AT z = 5.7: GALAXY BUILDING BLOCKS AND ENGINES OF REIONIZATION

    SciTech Connect (OSTI)

    Dressler, Alan; McCarthy, Patrick; Martin, Crystal L.; Henry, Alaina; Sawicki, Marcin E-mail: sawicki@ap.smu.ca

    2011-10-20

    We report results of an unprecedentedly deep, blind search for Ly{alpha} emitters (LAEs) at z = 5.7 using the Inamori-Magellan Areal Camera and Spectrograph (IMACS), with the goal of identifying missing sources of reionization that could also be basic building blocks for today's L* galaxies. We describe how improvements in wide field imaging with the Baade telescope, upgrades to IMACS, and the accumulation of {approx}20 hr of integration per field in excellent seeing led to the detection of single-emission-line sources as faint as F {approx} 2 x 10{sup -18} erg s{sup -1} cm{sup -2}, a sensitivity five times deeper than our first search. A reasonable correction for foreground interlopers implies a steep rise of approximately an order of magnitude in source density for a factor of four drop in flux, from F = 10{sup -17.0} erg s{sup -1} cm{sup -2} to F = 10{sup -17.6} (2.5 x 10{sup -18}) erg s{sup -1} cm{sup -2}. At this flux the putative LAEs have reached a surface density of {approx}1 arcmin{sup -2}-a comoving volume density of 4 x 10{sup -3} Mpc{sup -3}, several times the density of L* galaxies today. Such a population of faint LAEs would account for a significant fraction of the critical flux density required to complete reionization at this epoch, and would be good candidates for building blocks of stellar mass {approx}10{sup 8}-10{sup 9} M{sub sun} for the young galaxies of this epoch.

  15. Novel Approaches to High-Efficiency III-V Nitride Heterostructure Emitters for Next-Generation Lighting Applications

    SciTech Connect (OSTI)

    Russell D. Dupuis

    2006-01-01

    We report research activities and technical progress on the development of high-efficiency long wavelength ({lambda} {approx} 540nm) green light emitting diodes which covers the second year of the three-year program ''Novel approaches to high-efficiency III-V nitride heterostructure emitters for next-generation lighting applications''. The second year activities were focused on the development of p-type layer that has less/no detrimental thermal annealing effect on green LED active region as well as excellent structural and electrical properties and the development of green LED active region that has superior luminescence quality for {lambda} {approx}540nm green LEDs. We have also studied the thermal annealing effect on blue and green LED active region during the p-type layer growth. As a progress highlight, we obtained green-LED-active-region-friendly In{sub 0.04}Ga{sub 0.96}N:Mg exhibiting low resistivity with higher hole concentration (p=2.0 x 10{sup 18} cm{sup -3} and a low resistivity of 0.5 {Omega}-cm) and improved optical quality green LED active region emitting at {lambda} {approx}540nm by electroluminescence. The active region of the green LEDs was found to be much more sensitive to the thermal annealing effect during the p-type layer growth than that of the blue LEDs. We have designed grown, fabricated green LED structures for both 520 nm and 540 nm for the evaluation of second year green LED development.

  16. Large Group Visits

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

    Large Group Visits Large Group Visits All tours of the Museum are self-guided, but please schedule in advance so we can best accommodate your group. Contact Us thumbnail of 1350 Central Avenue (505) 667-4444 Email Let us know if you plan to bring a group of 10 or more. All tours of the Museum are self-guided, but please schedule in advance so we can best accommodate your group. Parking for buses and RVs is available on Iris Street behind the Museum off of 15th St. See attached map (pdf). Contact

  17. A Mock UF6 Feed and Withdrawal System for Testing Safeguards Monitoring Systems and Strategies Intended for Nuclear Fuel Enrichment and Processing Plants

    SciTech Connect (OSTI)

    Krichinsky, Alan M; Bates, Bruce E; Chesser, Joel B; Koo, Sinsze; Whitaker, J Michael

    2009-12-01

    This report describes an engineering-scale, mock UF6 feed and withdrawal (F&W) system, its operation, and its intended uses. This system has been assembled to provide a test bed for evaluating and demonstrating new methodologies that can be used in remote, unattended, continuous monitoring of nuclear material process operations. These measures are being investigated to provide independent inspectors improved assurance that operations are being conducted within declared parameters, and to increase the overall effectiveness of safeguarding nuclear material. Testing applicable technologies on a mock F&W system, which uses water as a surrogate for UF6, enables thorough and cost-effective investigation of hardware, software, and operational strategies before their direct installation in an industrial nuclear material processing environment. Electronic scales used for continuous load-cell monitoring also are described as part of the basic mock F&W system description. Continuous monitoring components on the mock F&W system are linked to a data aggregation computer by a local network, which also is depicted. Data collection and storage systems are described only briefly in this report. The mock UF{sub 6} F&W system is economical to operate. It uses a simple process involving only a surge tank between feed tanks and product and withdrawal (or waste) tanks. The system uses water as the transfer fluid, thereby avoiding the use of hazardous UF{sub 6}. The system is not tethered to an operating industrial process involving nuclear materials, thereby allowing scenarios (e.g., material diversion) that cannot be conducted otherwise. These features facilitate conducting experiments that yield meaningful results with a minimum of expenditure and quick turnaround time. Technologies demonstrated on the engineering-scale system lead to field trials (described briefly in this report) for determining implementation issues and performance of the monitoring technologies under plant

  18. Extra-Large Memory Nodes

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

    Extra-Large Memory Nodes Extra-Large Memory Nodes Extra-Large Memory Nodes Overview Carver has two "extra-large" memory nodes; each node has four 8-core Intel X7550 ("Nehalem EX")...

  19. Fluorescence enhancement in large-scale self-assembled gold nanoparticle double arrays

    SciTech Connect (OSTI)

    Chekini, M.; Bierwagen, J.; Cunningham, A.; Bürgi, T.; Filter, R.; Rockstuhl, C.

    2015-12-21

    Localized surface plasmon resonances excited in metallic nanoparticles confine and enhance electromagnetic fields at the nanoscale. This is particularly pronounced in dimers made from two closely spaced nanoparticles. When quantum emitters, such as dyes, are placed in the gap of those dimers, their absorption and emission characteristics can be modified. Both processes have to be considered when aiming to enhance the fluorescence from the quantum emitters. This is particularly challenging for dimers, since the electromagnetic properties and the enhanced fluorescence sensitively depend on the distance between the nanoparticles. Here, we use a layer-by-layer method to precisely control the distances in such systems. We consider a dye layer deposited on top of an array of gold nanoparticles or integrated into a central position of a double array of gold nanoparticles. We study the effect of the spatial arrangement and the average distance on the plasmon-enhanced fluorescence. We found a maximum of a 99-fold increase in the fluorescence intensity of the dye layer sandwiched between two gold nanoparticle arrays. The interaction of the dye layer with the plasmonic system also causes a spectral shift in the emission wavelengths and a shortening of the fluorescence life times. Our work paves the way for large-scale, high throughput, and low-cost self-assembled functionalized plasmonic systems that can be used as efficient light sources.

  20. Differential emitter geolocation

    DOE Patents [OSTI]

    Mason, John J.; Romero, Louis A.

    2015-08-18

    An unknown location of a transmitter of interest is determined based on wireless signals transmitted by both the transmitter of interest and a reference transmitter positioned at a known location. The transmitted signals are received at a plurality of non-earthbound platforms each moving in a known manner, and phase measurements for each received signal are used to determine the unknown location.

  1. Ceramic oxyanion emitter

    DOE Patents [OSTI]

    Delmore, J.E.; Appelhans, A.D.; Peterson, E.S.

    1996-04-09

    A rare earth oxide matrix (composition of matter) is formed which emits (upon heating) heavy metal oxide anions (oxyanions) into a gas phase, wherein the anions are emitted with high intensity, and wherein longevity of life of the composition of matter is retained. The matter is formed by blending a major component of a rare earth oxide, europium oxide (Eu{sub 2}O{sub 3}) or ytterbium oxide (Yb{sub 2}O{sub 3}), with a minor component of a barium (Ba), calcium (Ca) or strontium (Sr) salt of a heavy metal oxyanion. Heavy anions are emitted upon heating the composition of matter to a predetermined temperature of about 800 C.

  2. Ceramic oxyanion emitter

    DOE Patents [OSTI]

    Delmore, James E.; Appelhans, Anthony D.; Peterson, Eric S.

    1996-01-01

    A rare earth oxide matrix (composition of matter) is formed which emits (upon heating) heavy metal oxide anions (oxyanions) into a gas phase, wherein the anions are emitted with high intensity, and wherein longevity of life of the composition of matter is retained. The matter is formed by blending a major component of a rare earth oxide, Europium oxide (Eu.sub.2 O.sub.3) or Ytterbium oxide (Yb.sub.2 O.sub.3), with a minor component of a Barium (Ba), Calcium (Ca) or Strontium (Sr) salt of a heavy metal oxyanion. Heavy anions are emitted upon heating the composition of matter to a predetermined temperature of about 800.degree. C.

  3. Large Eddy Simulations: Where

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

    Eddy Simulations: Where observations and modeling collides July 18, 2015 Cascade of Models ⌅ General Circulation Models ⌅ Regional Models ⌅ Large-Eddy Simulations ⌅ Direct Numerical Simulations LES GCM vs LES History Theory What if? Using LES together with Observations Testbed LES 2 / 37 Cascade of Models General Circulation Models ⌅ Domain size: Entire Earth ⌅ Horizontal Boundary conditions: None ⌅ Horizontal grid spacing: 50km ⌅ Total number of points: about 400 ⇥ 400 ⇥ 100

  4. Meet with Large Businesses

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

    Meet with Large Businesses and learn about upcoming acquisitions! * Federal Energy Management Program (FEMP) * National Renewable Energy Laboratory (NREL) * Small Business Administration (SBA) * U.S. Department of Energy / Energy, Efficiency, and Renewable Energy (EERE) * U.S. Department of Energy / Golden Field Office (GFO) * Western Area Power Administration (WAPA) * Colorado Procurement Technical Assistance Center (PTAC) SMALL BUSINESS OUTREACH "Federal Contracting with Small

  5. Fabrication and characterization of large arrays of mesoscopic gold rings on large-aspect-ratio cantilevers

    SciTech Connect (OSTI)

    Ngo, D. Q.; Petkovi?, I. Lollo, A.; Castellanos-Beltran, M. A.; Harris, J. G. E.

    2014-10-15

    We have fabricated large arrays of mesoscopic metal rings on ultrasensitive cantilevers. The arrays are defined by electron beam lithography and contain up to 10{sup 5} rings. The rings have a circumference of 1 ?m, and are made of ultrapure (6N) Au that is deposited onto a silicon-on-insulator wafer without an adhesion layer. Subsequent processing of the SOI wafer results in each array being supported at the end of a free-standing cantilever. To accommodate the large arrays while maintaining a low spring constant, the cantilevers are nearly 1 mm in both lateral dimensions and 100 nm thick. The extreme aspect ratio of the cantilevers, the large array size, and the absence of a sticking layer are intended to enable measurements of the rings' average persistent current in the presence of relatively small magnetic fields. We describe the motivation for these measurements, the fabrication of the devices, and the characterization of the cantilevers' mechanical properties. We also discuss the devices' expected performance in measurements of .

  6. Faint submillimeter galaxies revealed by multifield deep ALMA observations: number counts, spatial clustering, and a dark submillimeter line emitter

    SciTech Connect (OSTI)

    Ono, Yoshiaki; Ouchi, Masami; Momose, Rieko; Kurono, Yasutaka

    2014-11-01

    We present the statistics of faint submillimeter/millimeter galaxies (SMGs) and serendipitous detections of a submillimeter/millimeter line emitter (SLE) with no multi-wavelength continuum counterpart revealed by the deep ALMA observations. We identify faint SMGs with flux densities of 0.1-1.0 mJy in the deep Band-6 and Band-7 maps of 10 independent fields that reduce cosmic variance effects. The differential number counts at 1.2 mm are found to increase with decreasing flux density down to 0.1 mJy. Our number counts indicate that the faint (0.1-1.0 mJy, or SFR{sub IR} ? 30-300 M {sub ?} yr{sup 1}) SMGs contribute nearly a half of the extragalactic background light (EBL), while the remaining half of the EBL is mostly contributed by very faint sources with flux densities of <0.1 mJy (SFR{sub IR} ? 30 M {sub ?} yr{sup 1}). We conduct counts-in-cells analysis with multifield ALMA data for the faint SMGs, and obtain a coarse estimate of galaxy bias, b {sub g} < 4. The galaxy bias suggests that the dark halo masses of the faint SMGs are ? 7 10{sup 12} M {sub ?}, which is smaller than those of bright (>1 mJy) SMGs, but consistent with abundant high-z star-forming populations, such as sBzKs, LBGs, and LAEs. Finally, we report the serendipitous detection of SLE-1, which has no continuum counterparts in our 1.2 mm-band or multi-wavelength images, including ultra deep HST/WFC3 and Spitzer data. The SLE has a significant line at 249.9 GHz with a signal-to-noise ratio of 7.1. If the SLE is not a spurious source made by the unknown systematic noise of ALMA, the strong upper limits of our multi-wavelength data suggest that the SLE would be a faint galaxy at z ? 6.

  7. Gyrokinetic large eddy simulations

    SciTech Connect (OSTI)

    Morel, P.; Navarro, A. Banon; Albrecht-Marc, M.; Carati, D.; Merz, F.; Goerler, T.; Jenko, F.

    2011-07-15

    The large eddy simulation approach is adapted to the study of plasma microturbulence in a fully three-dimensional gyrokinetic system. Ion temperature gradient driven turbulence is studied with the GENE code for both a standard resolution and a reduced resolution with a model for the sub-grid scale turbulence. A simple dissipative model for representing the effect of the sub-grid scales on the resolved scales is proposed and tested. Once calibrated, the model appears to be able to reproduce most of the features of the free energy spectra for various values of the ion temperature gradient.

  8. Large Particle Titanate Sorbents

    SciTech Connect (OSTI)

    Taylor-Pashow, K.

    2015-10-08

    This research project was aimed at developing a synthesis technique for producing large particle size monosodium titanate (MST) to benefit high level waste (HLW) processing at the Savannah River Site (SRS). Two applications were targeted, first increasing the size of the powdered MST used in batch contact processing to improve the filtration performance of the material, and second preparing a form of MST suitable for deployment in a column configuration. Increasing the particle size should lead to improvements in filtration flux, and decreased frequency of filter cleaning leading to improved throughput. Deployment of MST in a column configuration would allow for movement from a batch process to a more continuous process. Modifications to the typical MST synthesis led to an increase in the average particle size. Filtration testing on dead-end filters showed improved filtration rates with the larger particle material; however, no improvement in filtration rate was realized on a crossflow filter. In order to produce materials suitable for column deployment several approaches were examined. First, attempts were made to coat zirconium oxide microspheres (196 µm) with a layer of MST. This proved largely unsuccessful. An alternate approach was then taken synthesizing a porous monolith of MST which could be used as a column. Several parameters were tested, and conditions were found that were able to produce a continuous structure versus an agglomeration of particles. This monolith material showed Sr uptake comparable to that of previously evaluated samples of engineered MST in batch contact testing.

  9. Sean Large | Department of Energy

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

    Sean Large Sean Large Sean Large - Intern with the Office of Energy Efficiency and Renewable Energy Most Recent Be Part of the Solution! June 22 What's Up With Fuel Cells? June 8

  10. Experimental evidences for emittance degradation by space charge effect when using a focusing solenoid below an electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Machicoane, G.; Doleans, M.; Stetson, J.; Wu, X.; Zavodszky, P. A.

    2008-02-15

    Solenoids are widely used to provide initial focusing of beams extracted from an ion source. However, in the case of an electron cyclotron resonance (ECR) ion source, the extracted beam will usually include different ion species and for each of them a wide distribution of charge states. When such a multicomponent beam is focused by a solenoid, the ions with a Q/A larger than the beam of interest are overfocused and usually go through a waist before reaching the analyzing magnet. If the beam currents obtained for these ions are sufficient, the resulting space charge forces can significantly degrade the emittance of the beam components with a lower Q/A and result for those in a hollow beam. Using a beam viewer and an emittance-measuring device, this paper reports on experimental findings that confirm the existence of such an effect for low charge states of argon. Moreover, by changing the experimental conditions of the ECR plasma in order to modify the charge state distribution of the extracted ion beam, it is shown that the threshold where this space charge effect starts to be significant can be changed.

  11. Back-junction back-contact n-type silicon solar cell with diffused boron emitter locally blocked by implanted phosphorus

    SciTech Connect (OSTI)

    Mller, Ralph Schrof, Julian; Reichel, Christian; Benick, Jan; Hermle, Martin

    2014-09-08

    The highest energy conversion efficiencies in the field of silicon-based photovoltaics have been achieved with back-junction back-contact (BJBC) silicon solar cells by several companies and research groups. One of the most complex parts of this cell structure is the fabrication of the locally doped p- and n-type regions, both on the back side of the solar cell. In this work, we introduce a process sequence based on a synergistic use of ion implantation and furnace diffusion. This sequence enables the formation of all doped regions for a BJBC silicon solar cell in only three processing steps. We observed that implanted phosphorus can block the diffusion of boron atoms into the silicon substrate by nearly three orders of magnitude. Thus, locally implanted phosphorus can be used as an in-situ mask for a subsequent boron diffusion which simultaneously anneals the implanted phosphorus and forms the boron emitter. BJBC silicon solar cells produced with such an easy-to-fabricate process achieved conversion efficiencies of up to 21.7%. An open-circuit voltage of 674?mV and a fill factor of 80.6% prove that there is no significant recombination at the sharp transition between the highly doped emitter and the highly doped back surface field at the device level.

  12. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Large Magnetization at Carbon Surfaces Print Wednesday, 31 August 2011 00:00 From organic matter to pencil lead, carbon is a versatile...

  13. Large forging manufacturing process

    DOE Patents [OSTI]

    Thamboo, Samuel V.; Yang, Ling

    2002-01-01

    A process for forging large components of Alloy 718 material so that the components do not exhibit abnormal grain growth includes the steps of: a) providing a billet with an average grain size between ASTM 0 and ASTM 3; b) heating the billet to a temperature of between 1750.degree. F. and 1800.degree. F.; c) upsetting the billet to obtain a component part with a minimum strain of 0.125 in at least selected areas of the part; d) reheating the component part to a temperature between 1750.degree. F. and 1800.degree. F.; e) upsetting the component part to a final configuration such that said selected areas receive no strains between 0.01 and 0.125; f) solution treating the component part at a temperature of between 1725.degree. F. and 1750.degree. F.; and g) aging the component part over predetermined times at different temperatures. A modified process achieves abnormal grain growth in selected areas of a component where desirable.

  14. Large scale tracking algorithms.

    SciTech Connect (OSTI)

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  15. EM Active Sites (large) | Department of Energy

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

    Active Sites (large) EM Active Sites (large) Center

  16. Radio Frequency Noise Effects on the CERN Large Hadron Collider Beam Diffusion

    SciTech Connect (OSTI)

    Mastoridis, T.; Baudrenghien, P.; Butterworth, A.; Molendijk, J.; Rivetta, C.; Fox, J.D.; /SLAC

    2012-04-30

    Radio frequency (rf) accelerating system noise can have a detrimental impact on the Large Hadron Collider (LHC) performance through longitudinal motion and longitudinal emittance growth. A theoretical formalism has been developed to relate the beam and rf station dynamics with the bunch length growth. Measurements were conducted at LHC to determine the performance limiting rf components and validate the formalism through studies of the beam diffusion dependence on rf noise. As a result, a noise threshold was established for acceptable performance which provides the foundation for beam diffusion estimates for higher energies and intensities. Measurements were also conducted to determine the low level rf noise spectrum and its major contributions, as well as to validate models and simulations of this system.

  17. Ion sources with arc-discharge plasma box driven by directly heated LaB{sub 6} electron emitter or cold cathode (invited)

    SciTech Connect (OSTI)

    Ivanov, Alexander A.; Davydenko, Vladimir I.; Deichuli, Petr P.; Shulzhenko, Grigori I.; Stupishin, Nikolay V.

    2008-02-15

    In the Budker Institute, Novosibirsk, an ion source with arc-discharge plasma box has been developed in the recent years for application in thermonuclear devices for plasma diagnostics. Several modifications of the ion source were provided with extracted current ranging from 1 to 7 A and pulse duration of up to 4 s. Initially, the arc-discharge plasma box with cold cathode was used, with which pulse duration is limited to 2 s by the cathode overheating and sputtering in local arc spots. Recently, a directly heated LaB{sub 6} electron emitter was employed instead, which has extended lifetime compared to the cold cathode. In the paper, characteristics of the beam produced with both arrangements of the plasma box are presented.

  18. Look At (Search) Large Files

    Energy Science and Technology Software Center (OSTI)

    1992-07-13

    Scanning large files for information can be time consuming and expensive when using edit utilities on large mainframe computers. The reason is that editors must usually load the file into a buffer.

  19. Extra-Large Memory Nodes

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

    Extra-Large Memory Nodes Extra-Large Memory Nodes Extra-Large Memory Nodes Overview Carver has two "extra-large" memory nodes; each node has four 8-core Intel X7550 ("Nehalem EX") 2.0 GHz processors (32 cores total) and 1TB memory. These nodes are available through the queue "reg_xlmem". They can be used for interactive and batch jobs that require large amount of memory (16GB per core or more). reg_xlmem queue Please refer to the "Queues and Policies" page

  20. Large

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

    ... at the beginning of the discharge, which could damage the detectors. The shutter has a finite opening time of 3 ms. After laser fire is given to the laser, roughly 1.25 ms are ...

  1. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure...

  2. Coordinated Multi-layer Multi-domain Optical Network (COMMON) for Large-Scale Science Applications (COMMON)

    SciTech Connect (OSTI)

    Vokkarane, Vinod

    2013-09-01

    We intend to implement a Coordinated Multi-layer Multi-domain Optical Network (COMMON) Framework for Large-scale Science Applications. In the COMMON project, specific problems to be addressed include 1) anycast/multicast/manycast request provisioning, 2) deployable OSCARS enhancements, 3) multi-layer, multi-domain quality of service (QoS), and 4) multi-layer, multidomain path survivability. In what follows, we outline the progress in the above categories (Year 1, 2, and 3 deliverables).

  3. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Large Magnetization at Carbon Surfaces Print Wednesday, 31 August 2011 00:00 From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the

  4. Large-Scale Field Study of Landfill Covers at Sandia National Laboratories

    SciTech Connect (OSTI)

    Dwyer, S.F.

    1998-09-01

    A large-scale field demonstration comparing final landfill cover designs has been constructed and is currently being monitored at Sandia National Laboratories in Albuquerque, New Mexico. Two conventional designs (a RCRA Subtitle `D' Soil Cover and a RCRA Subtitle `C' Compacted Clay Cover) were constructed side-by-side with four alternative cover test plots designed for dry environments. The demonstration is intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. This paper presents an overview of the ongoing demonstration.

  5. CRADA 2009S001: Investigation of the Supercondcuting RF Properties of Large Grain Ingot Niobium

    SciTech Connect (OSTI)

    Grimm, Terry; Hollister, Jerry L.; Kolka, Ahren; Myneni, Ganapati Rao

    2012-12-18

    This CRADA intended to explore the properties of large grain ingot niobium by fabricating four single cell TESLA shaped accelerating cavities. Once the cavities were fabricated, SRF performance would be measured. Niowave received four discs of large grain ingot niobium from JLAB in February 2009. Niowave cut samples from each disc and tested the RRR. After the RRR was measured with disappointing results, the project lost interest. A no cost extension was signed in July 2009 to allow progress until June 2010, but ultimately no further work was accomplished by either party. No firm conclusions were drawn, as further investigations were not made. Large grain ingot niobium has shown real potential for high accelerating gradient superconducting cavities. However, this particular CRADA did not gather enough data to reach any conclusions in this regard.

  6. Technical Support Document: Development of the Advanced Energy Design Guide for Large Hospitals - 50% Energy Savings

    SciTech Connect (OSTI)

    Bonnema, E.; Leach, M.; Pless, S.

    2013-06-01

    This Technical Support Document describes the process and methodology for the development of the Advanced Energy Design Guide for Large Hospitals: Achieving 50% Energy Savings Toward a Net Zero Energy Building (AEDG-LH) ASHRAE et al. (2011b). The AEDG-LH is intended to provide recommendations for achieving 50% whole-building energy savings in large hospitals over levels achieved by following Standard 90.1-2004. The AEDG-LH was created for a 'standard' mid- to large-size hospital, typically at least 100,000 ft2, but the strategies apply to all sizes and classifications of new construction hospital buildings. Its primary focus is new construction, but recommendations may be applicable to facilities undergoing total renovation, and in part to many other hospital renovation, addition, remodeling, and modernization projects (including changes to one or more systems in existing buildings).

  7. Chunking of Large Multidimensional Arrays

    SciTech Connect (OSTI)

    Rotem, Doron; Otoo, Ekow J.; Seshadri, Sridhar

    2007-02-28

    Data intensive scientific computations as well on-lineanalytical processing applications as are done on very large datasetsthat are modeled as k-dimensional arrays. The storage organization ofsuch arrays on disks is done by partitioning the large global array intofixed size hyper-rectangular sub-arrays called chunks or tiles that formthe units of data transfer between disk and memory. Typical queriesinvolve the retrieval of sub-arrays in a manner that accesses all chunksthat overlap the query results. An important metric of the storageefficiency is the expected number of chunks retrieved over all suchqueries. The question that immediately arises is "what shapes of arraychunks give the minimum expected number of chunks over a query workload?"In this paper we develop two probabilistic mathematical models of theproblem and provide exact solutions using steepest descent and geometricprogramming methods. Experimental results, using synthetic workloads onreal life data sets, show that our chunking is much more efficient thanthe existing approximate solutions.

  8. 2014-11-25 Issuance: Energy Conservation Standards for Small, Large, and Very Large Air-cooled Commercial Package Air Conditioning and Heating Equipment; Extension of Public Comment Period

    Broader source: Energy.gov [DOE]

    This document is a pre-publication Federal Register extension of the public comment period regarding energy conservation standards for small, large and very large air-cool commercial package air conditioning and heating equipment, as issued by the Deputy Assistant Secretary for Energy Efficiency on November 25, 2014. Though it is not intended or expected, should any discrepancy occur between the document posted here and the document published in the Federal Register, the Federal Register publication controls. This document is being made available through the Internet solely as a means to facilitate the public's access to this document.

  9. 2014-09-18 Issuance: Energy Conservation Standard for Small, Large, and Very Large Air-Cooled Commercial Package Air Conditioning and Heating Equipment; Notice of Proposed Rulemaking and Public Meeting

    Broader source: Energy.gov [DOE]

    This document is a pre-publication Federal Register Notice of Proposed Rulemaking and Public Meeting regarding Energy Conservation Standards for Small, large, and Very Large Air-Cooled Commercial Package Air Conditioning and Heating Equipment, as issued by the Assistant Secretary for Energy Efficiency and Renewable Energy on September 18, 2014. Though it is not intended or expected, should any discrepancy occur between the document posted here and the document published in the Federal Register, the Federal Register publication controls. This document is being made available through the Internet solely as a means to facilitate the public's access to this document.

  10. Large Component Removal/Disposal

    SciTech Connect (OSTI)

    Wheeler, D. M.

    2002-02-27

    This paper describes the removal and disposal of the large components from Maine Yankee Atomic Power Plant. The large components discussed include the three steam generators, pressurizer, and reactor pressure vessel. Two separate Exemption Requests, which included radiological characterizations, shielding evaluations, structural evaluations and transportation plans, were prepared and issued to the DOT for approval to ship these components; the first was for the three steam generators and one pressurizer, the second was for the reactor pressure vessel. Both Exemption Requests were submitted to the DOT in November 1999. The DOT approved the Exemption Requests in May and July of 2000, respectively. The steam generators and pressurizer have been removed from Maine Yankee and shipped to the processing facility. They were removed from Maine Yankee's Containment Building, loaded onto specially designed skid assemblies, transported onto two separate barges, tied down to the barges, th en shipped 2750 miles to Memphis, Tennessee for processing. The Reactor Pressure Vessel Removal Project is currently under way and scheduled to be completed by Fall of 2002. The planning, preparation and removal of these large components has required extensive efforts in planning and implementation on the part of all parties involved.

  11. Thin-channel electrospray emitter

    DOE Patents [OSTI]

    Van Berkel, Gary J.

    2004-08-31

    An electrospray device includes a high voltage electrode chamber. The high voltage electrode chamber includes an inlet for receiving a fluid to be ionized and for directing the fluid into the chamber and at least one electrode having an exposed surface within the chamber. A flow channel directs fluid over a surface of the electrode and out of the chamber. The length of the flow channel over the electrode is greater than the height of the flow channel over the electrode, thereby producing enhanced mass transport to the working electrode resulting in improved electrolysis efficiency. An outlet is provided for transmitting the fluid out from the electrode chamber. A method of creating charged droplets includes flowing a fluid over an electrode where the length over the electrode is greater than the height of the fluid flowing over the electrode.

  12. Large-bore pipe decontamination

    SciTech Connect (OSTI)

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system.

  13. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  14. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  15. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  16. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  17. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  18. the Large Aperture GRB Observatory

    SciTech Connect (OSTI)

    Bertou, Xavier

    2009-04-30

    The Large Aperture GRB Observatory (LAGO) aims at the detection of high energy photons from Gamma Ray Bursts (GRB) using the single particle technique (SPT) in ground based water Cherenkov detectors (WCD). To reach a reasonable sensitivity, high altitude mountain sites have been selected in Mexico (Sierra Negra, 4550 m a.s.l.), Bolivia (Chacaltaya, 5300 m a.s.l.) and Venezuela (Merida, 4765 m a.s.l.). We report on the project progresses and the first operation at high altitude, search for bursts in 6 months of preliminary data, as well as search for signal at ground level when satellites report a burst.

  19. LHC: The Large Hadron Collider

    SciTech Connect (OSTI)

    Lincoln, Don

    2015-03-04

    The Large Hadron Collider (or LHC) is the world’s most powerful particle accelerator. In 2012, scientists used data taken by it to discover the Higgs boson, before pausing operations for upgrades and improvements. In the spring of 2015, the LHC will return to operations with 163% the energy it had before and with three times as many collisions per second. It’s essentially a new and improved version of itself. In this video, Fermilab’s Dr. Don Lincoln explains both some of the absolutely amazing scientific and engineering properties of this modern scientific wonder.

  20. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  1. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  2. STELLAR POPULATIONS OF Ly{alpha} EMITTERS AT z = 4.86: A COMPARISON TO z {approx} 5 LYMAN BREAK GALAXIES

    SciTech Connect (OSTI)

    Yuma, Suraphong; Ohta, Kouji; Yabe, Kiyoto; Shimasaku, Kazuhiro; Yoshida, Makiko; Ouchi, Masami; Iwata, Ikuru; Sawicki, Marcin

    2010-09-10

    We present a study of a stellar population of Ly{alpha} emitters (LAEs) at z = 4.86 in the Great Observatories Origins Deep Survey North (GOODS-N) field and its flanking field. The LAEs are selected based on optical narrowband (NB711) and broadband (V, I{sub c} , and z') observations by the Suprime-Cam attached to the Subaru Telescope. With the publicly available Infrared Array Camera (IRAC) data in GOODS-N and further IRAC observations in the flanking fields, we select five LAEs that are not contaminated by neighboring objects in IRAC images and construct their observed spectral energy distributions (SEDs) with I{sub c} , z', IRAC 3.6 {mu}m, and 4.5 {mu}m band photometries. The SEDs cover the rest-frame UV-to-optical wavelengths. We derive the stellar masses, ages, color excesses, and star formation rates (SFRs) of the five LAEs using an SED fitting method. Assuming a constant star formation history, we find that the stellar masses range from 10{sup 8} to 10{sup 10} M {sub sun} with the median value of 2.5 x 10{sup 9} M{sub sun}. The derived ages range from very young (7.4 Myr) to 437 Myr, with a median age of 25 Myr. The color excess E(B - V) is between 0.1and0.4 mag. SFRs are 55-209 M{sub sun} yr{sup -1}. A comparison of the stellar populations is made between 3 LAEs and 88 Lyman break galaxies (LBGs) selected at the same redshift, in the same observed field, and down to the same limit of the rest-frame UV luminosity. These three LAEs are the brightest and reddest samples of all the LAE samples at z = 4.86. The LAEs are distributed at the relatively faint part of the UV-luminosity distribution of LBGs. Deriving the stellar properties of the LBGs by fitting their SEDs with the same model ensures that model difference does not affect the comparison. It is found that the stellar properties of the LAEs are located in the region where the properties of LBGs are distributed. On average, the LAEs show less dust extinction and lower SFRs than LBGs, while the stellar

  3. STELLAR POPULATIONS OF Ly{alpha} EMITTERS AT z {approx} 6-7: CONSTRAINTS ON THE ESCAPE FRACTION OF IONIZING PHOTONS FROM GALAXY BUILDING BLOCKS

    SciTech Connect (OSTI)

    Ono, Yoshiaki; Shimasaku, Kazuhiro; Okamura, Sadanori; Masami Ouchi; Dunlop, James; Farrah, Duncan; McLure, Ross

    2010-12-01

    We investigate the stellar populations of Ly{alpha} emitters (LAEs) at z = 5.7 and 6.6 in a 0.65 deg{sup 2} sky of the Subaru/XMM-Newton Deep Survey (SXDS) Field, using deep images taken with the Subaru/Suprime-Cam, United Kingdom Infrared Telescope/Wide Field Infrared Camera, and Spitzer/Infrared Array Camera (IRAC). We produce stacked multiband images at each redshift from 165 (z = 5.7) and 91 (z = 6.6) IRAC-undetected objects to derive typical spectral energy distributions (SEDs) of z {approx} 6-7 LAEs for the first time. The stacked LAEs have as blue UV continua as the Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) z-dropout galaxies of similar M{sub UV}, with a spectral slope {beta} {approx} -3, but at the same time they have red UV-to-optical colors with detection in the 3.6 {mu}m band. Using SED fitting we find that the stacked LAEs have low stellar masses of {approx}(3-10) x 10{sup 7} M{sub sun}, very young ages of {approx}1-3 Myr, negligible dust extinction, and strong nebular emission from the ionized interstellar medium, although the z = 6.6 object is fitted similarly well with high-mass models without nebular emission; inclusion of nebular emission reproduces the red UV-to-optical colors while keeping the UV colors sufficiently blue. We infer that typical LAEs at z {approx} 6-7 are building blocks of galaxies seen at lower redshifts. We find a tentative decrease in the Ly{alpha} escape fraction from z = 5.7 to 6.6, which may imply an increase in the intergalactic medium neutral fraction. From the minimum contribution of nebular emission required to fit the observed SEDs, we place an upper limit on the escape fraction of ionizing photons of f {sup ion}{sub esc} {approx} 0.6 at z = 5.7 and {approx}0.9 at z = 6.6. We also compare the stellar populations of our LAEs with those of stacked HST/WFC3 z-dropout galaxies.

  4. Dependence of beam emittance on plasma electrode temperature and rf-power, and filter-field tuning with center-gapped rod-filter magnets in J-PARC rf-driven H{sup ?} ion source

    SciTech Connect (OSTI)

    Ueno, A. Koizumi, I.; Ohkoshi, K.; Ikegami, K.; Takagi, A.; Yamazaki, S.; Oguri, H.

    2014-02-15

    The prototype rf-driven H{sup ?} ion-source with a nickel plated oxygen-free-copper (OFC) plasma chamber, which satisfies the Japan Proton Accelerator Research Complex (J-PARC) 2nd stage requirements of a H{sup ?} ion beam current of 60 mA within normalized emittances of 1.5 ? mm mrad both horizontally and vertically, a flat top beam duty factor of 1.25% (500 ?s 25 Hz) and a life-time of more than 50 days, was reported at the 3rd international symposium on negative ions, beams, and sources (NIBS2012). The experimental results of the J-PARC ion source with a plasma chamber made of stainless-steel, instead of nickel plated OFC used in the prototype source, are presented in this paper. By comparing these two sources, the following two important results were acquired. One was that the about 20% lower emittance was produced by the rather low plasma electrode (PE) temperature (T{sub PE}) of about 120?C compared with the typically used T{sub PE} of about 200?C to maximize the beam current for the plasma with the abundant cesium (Cs). The other was that by using the rod-filter magnets with a gap at each center and tuning the gap-lengths, the filter-field was optimized and the rf-power necessary to produce the J-PARC required H{sup ?} ion beam current was reduced typically 18%. The lower rf-power also decreases the emittances.

  5. Search for Large Extra Dimensions Based on Observations of Neutron Stars with the Fermi-LAT

    SciTech Connect (OSTI)

    Berenji, Bijan; /Stanford U., Appl. Phys. Dept. /SLAC

    2012-09-19

    Large extra dimensions (LED) have been proposed to account for the apparent weakness of gravitation. These theories also indicate that the postulated massive Kaluza-Klein (KK) gravitons may be produced by nucleon-nucleon bremsstrahlung in the course of core collapse of supernovae. Hannestad and Raffelt have predicted energy spectra of gamma ray emission from the decay of KK gravitons trapped by the gravity of the remnant neutron stars (NS). These and other authors have used EGRET data on NS to obtain stringent limits on LED. Fermi-LAT is observing radio pulsar positions obtained from radio and x-ray catalogs. NS with certain characteristics are unlikely emitter of gamma rays, and emit in radio and perhaps x-rays. This talk will focus on the blind analysis we plan to perform, which has been developed using the 1st 2 months of all sky data and Monte Carlo simulations, to obtain limits on LED based on about 1 year of Fermi-LAT data. Preliminary limits from this analysis using these first 2 months of data will be also be discussed.

  6. Conceptual design of hollow electron lenses for beam halo control in the Large Hadron Collider

    SciTech Connect (OSTI)

    Stancari, Giulio; Previtali, Valentina; Valishev, Alexander; Bruce, Roderik; Redaelli, Stefano; Rossi, Adriana; Salvachua Ferrando, Belen

    2014-05-08

    Collimation with hollow electron beams is a technique for halo control in high-power hadron beams. It is based on an electron beam (possibly pulsed or modulated in intensity) guided by strong axial magnetic fields which overlaps with the circulating beam in a short section of the ring. The concept was tested experimentally at the Fermilab Tevatron collider using a hollow electron gun installed in one of the Tevatron electron lenses. Within the US LHC Accelerator Research Program (LARP) and the European FP7 HiLumi LHC Design Study, we are proposing a conceptual design for applying this technique to the Large Hadron Collider at CERN. A prototype hollow electron gun for the LHC was built and tested. The expected performance of the hollow electron beam collimator was based on Tevatron experiments and on numerical tracking simulations. Halo removal rates and enhancements of halo diffusivity were estimated as a function of beam and lattice parameters. Proton beam core lifetimes and emittance growth rates were checked to ensure that undesired effects were suppressed. Hardware specifications were based on the Tevatron devices and on preliminary engineering integration studies in the LHC machine. Required resources and a possible timeline were also outlined, together with a brief discussion of alternative halo-removal schemes and of other possible uses of electron lenses to improve the performance of the LHC.

  7. Large-scale clustering of Lymanα emission intensity from SDSS/BOSS

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

    Croft, Rupert A. C.; Miralda-Escudé, Jordi; Zheng, Zheng; Bolton, Adam; Dawson, Kyle S.; Peterson, Jeffrey B.; York, Donald G.; Eisenstein, Daniel; Brinkmann, Jon; Brownstein, Joel; et al

    2016-01-27

    Here we present a tentative detection of the large-scale structure of Ly α emission in the Universe at redshifts z = 2–3.5 by measuring the cross-correlation of Ly α surface brightness with quasars in Sloan Digital Sky Survey/Baryon Oscillation Spectroscopic Survey. We use a million spectra targeting luminous red galaxies at z < 0.8, after subtracting a best-fitting model galaxy spectrum from each one, as an estimate of the high-redshift Ly α surface brightness. The quasar–Ly α emission cross-correlation is detected on scales 1 ~ 15h₋1 Mpc, with shape consistent with a ΛCDM model with Ωm =0.30±0.100.07. The predicted amplitudemore » of this cross- correlation is proportional to the product of the mean Lyα surface brightness, {μα}, the amplitude of mass density fluctuations, and the quasar and Lyα emission bias factors. Using published cosmological observations to constrain the amplitude of mass fluctuations and the quasar bias factor, we infer the value of the product {μα} (bα /3) = (3.9±0.9)×10₋21 erg s₋1 cm₋2 °A₋1 arcsec₋2, where bα is the Lyα emission linear bias factor. If the dominant sources of Lyα emission we measure are star forming galaxies, we infer a total mean star formation rate density of ρSFR = (0.28 ± 0.07)(3/bα ) yr₋1 Mpc₋3 at z = 2 ₋ 3.5. For bα = 3, this value is a factor of 21 ₋ 35 above previous estimates relying on individually detected Lyα emitters, although it is consistent with the total star-formation density derived from dust-corrected, continuum UV surveys. Our observations therefore imply that 97% of the Lyα emission in the Universe at these redshifts is undetected in previous surveys of Lyα emitters. Our detected Lyα emission is also much greater, by at least an order of magnitude, than that measured from stacking analyses of faint halos surrounding previously detected Lyα emitters, but we speculate that it arises from similar low surface brightness Lyα halos surrounding all

  8. Large-Scale Information Systems

    SciTech Connect (OSTI)

    D. M. Nicol; H. R. Ammerlahn; M. E. Goldsby; M. M. Johnson; D. E. Rhodes; A. S. Yoshimura

    2000-12-01

    Large enterprises are ever more dependent on their Large-Scale Information Systems (LSLS), computer systems that are distinguished architecturally by distributed components--data sources, networks, computing engines, simulations, human-in-the-loop control and remote access stations. These systems provide such capabilities as workflow, data fusion and distributed database access. The Nuclear Weapons Complex (NWC) contains many examples of LSIS components, a fact that motivates this research. However, most LSIS in use grew up from collections of separate subsystems that were not designed to be components of an integrated system. For this reason, they are often difficult to analyze and control. The problem is made more difficult by the size of a typical system, its diversity of information sources, and the institutional complexities associated with its geographic distribution across the enterprise. Moreover, there is no integrated approach for analyzing or managing such systems. Indeed, integrated development of LSIS is an active area of academic research. This work developed such an approach by simulating the various components of the LSIS and allowing the simulated components to interact with real LSIS subsystems. This research demonstrated two benefits. First, applying it to a particular LSIS provided a thorough understanding of the interfaces between the system's components. Second, it demonstrated how more rapid and detailed answers could be obtained to questions significant to the enterprise by interacting with the relevant LSIS subsystems through simulated components designed with those questions in mind. In a final, added phase of the project, investigations were made on extending this research to wireless communication networks in support of telemetry applications.

  9. 2007 CBECS Large Hospital Building FAQs

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    See the 2007 CBECS Large Hospital Building Methodology Report for details. Why are you publishing estimates only for large hospitals and not the rest of the commercial building ...

  10. Director's colloquium March 18 large hadron collider

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

    Director's colloquium large hadron collider Director's colloquium March 18 large hadron collider Lyndon Evans of CERN will talk about the most complex scientific instrument ever ...

  11. A novel process for recycling and resynthesizing LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} from the cathode scraps intended for lithium-ion batteries

    SciTech Connect (OSTI)

    Zhang, Xihua; Xie, Yongbing; Cao, Hongbin; Nawaz, Faheem; Zhang, Yi

    2014-09-15

    Highlights: • A simple process to recycle cathode scraps intended for lithium-ion batteries. • Complete separation of the cathode material from the aluminum foil is achieved. • The recovered aluminum foil is highly pure. • LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} is directly resynthesized from the separated cathode material. - Abstract: To solve the recycling challenge for aqueous binder based lithium-ion batteries (LIBs), a novel process for recycling and resynthesizing LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} from the cathode scraps generated during manufacturing process is proposed in this study. Trifluoroacetic acid (TFA) is employed to separate the cathode material from the aluminum foil. The effects of TFA concentration, liquid/solid (L/S) ratio, reaction temperature and time on the separation efficiencies of the cathode material and aluminum foil are investigated systematically. The cathode material can be separated completely under the optimal experimental condition of 15 vol.% TFA solution, L/S ratio of 8.0 mL g{sup −1}, reacting at 40 °C for 180 min along with appropriate agitation. LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} is successfully resynthesized from the separated cathode material by solid state reaction method. Several kinds of characterizations are performed to verify the typical properties of the resynthesized LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} powder. Electrochemical tests show that the initial charge and discharge capacities of the resynthesized LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} are 201 mAh g{sup −1} and 155.4 mAh g{sup −1} (2.8–4.5 V, 0.1 C), respectively. The discharge capacity remains at 129 mAh g{sup −1} even after 30 cycles with a capacity retention ratio of 83.01%.

  12. Large optics inspection, tilting, and washing stand

    DOE Patents [OSTI]

    Ayers, Marion Jay; Ayers, Shannon Lee

    2010-08-24

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  13. Large optics inspection, tilting, and washing stand

    DOE Patents [OSTI]

    Ayers, Marion Jay; Ayers, Shannon Lee

    2012-10-09

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  14. X-RAY PROPERTIES OF THE z {approx} 4.5 Ly{alpha} EMITTERS IN THE CHANDRA DEEP FIELD SOUTH REGION

    SciTech Connect (OSTI)

    Zheng, Z. Y.; Wang, J. X.; Finkelstein, S. L.; Finkelstein, K. D.; Malhotra, S.; Rhoads, J. E. E-mail: jxw@ustc.edu.c

    2010-07-20

    We report the first X-ray detection of Ly{alpha} emitters (LAEs) at redshift z {approx} 4.5. One source (J033127.2-274247) is detected in the Extended Chandra Deep Field-South (ECDF-S) X-ray data and has been spectroscopically confirmed as a z = 4.48 quasar with L{sub X} = 4.2 x 10{sup 44} erg s{sup -1}. The single detection gives an Ly{alpha} quasar density of {approx} 2.7{sup +6.2} {sub -2.2} x 10{sup -6} Mpc{sup -3}, consistent with the X-ray luminosity function of quasars. Another 22 LAEs in the central Chandra Deep Field-South region are not detected individually, but their co-added counts yield an S/N = 2.4 (p = 99.83%) detection at soft band, with an effective exposure time of {approx}36 Ms. Further analysis of the equivalent width (EW) distribution shows that all the signals come from 12 LAE candidates with EW{sub rest}< 400 A and 2 of them contribute about half of the signal. From follow-up spectroscopic observations, we find that one of the two is a low-redshift emission-line galaxy, and the other is a Lyman break galaxy at z = 4.4 with little or no Ly{alpha} emission. Excluding these two and combined with ECDF-S data, we derive a 3{sigma} upper limit on the average X-ray flux of F {sub 0.5-2.0keV} < 1.6 x 10{sup -18} erg cm{sup -2} s{sup -1}, which corresponds to an average luminosity of (L {sub 0.5-2keV}) <2.4 x 10{sup 42} erg s{sup -1} for z {approx} 4.5 LAEs. If the average X-ray emission is due to star formation, it corresponds to a star formation rate (SFR) of <180-530 M {sub sun} yr{sup -1}. We use this SFR {sub X} as an upper limit of the unobscured SFR to constrain the escape fraction of Ly{alpha} photons and find a lower limit of f{sub esc,Ly{alpha}} > 3%-10%. However, our upper limit on the SFR {sub X} is {approx}7 times larger than the upper limit on SFR {sub X} on z {approx} 3.1 LAEs in the same field and at least 30 times higher than the SFR estimated from Ly{alpha} emission. From the average X-ray-to-Ly{alpha} line ratio, we estimate that

  15. Large-area Silicon-Film{trademark} panels and solar cells. Phase 2 technical report, January 1996--December 1996

    SciTech Connect (OSTI)

    Rand, J.A.; Barnett, A.M.; Checchi, J.C.; Culik, J.S.; Collins, S.R.; Ford, D.H.; Hall, R.B.; Jackson, E.L.; Kendall, C.L.

    1997-03-01

    The Silicon-Film{trademark} process is on an accelerated path to large-scale manufacturing. A key element in that development is optimizing the specific geometry of both the Silicon-Film{trademark} sheet and the resulting solar cell. That decision has been influenced by cost factors, engineering concerns, and marketing issues. The geometry investigation has focused first on sheet nominally 15 cm wide. This sheet generated solar cells with areas of 240 cm{sup 2} and 675 cm{sup 2}. Most recently, a new sheet fabrication machine was constructed that produces Silicon-Film{trademark} with a width in excess of 30 cm. Test results have indicated that there is no limit to the width of sheet generated by this process. The new wide material has led to prototype solar cells with areas of 300, 400, and 1,800 cm{sup 2}. Significant advances in solar-cell processing have been developed in support of fabricating large-area devices, including uniform emitter diffusion and anti-reflection coatings.

  16. Strain-Based Design Methodology of Large Diameter Grade X80 Linepipe

    SciTech Connect (OSTI)

    Lower, Mark D.

    2014-04-01

    Continuous growth in energy demand is driving oil and natural gas production to areas that are often located far from major markets where the terrain is prone to earthquakes, landslides, and other types of ground motion. Transmission pipelines that cross this type of terrain can experience large longitudinal strains and plastic circumferential elongation as the pipeline experiences alignment changes resulting from differential ground movement. Such displacements can potentially impact pipeline safety by adversely affecting structural capacity and leak tight integrity of the linepipe steel. Planning for new long-distance transmission pipelines usually involves consideration of higher strength linepipe steels because their use allows pipeline operators to reduce the overall cost of pipeline construction and increase pipeline throughput by increasing the operating pressure. The design trend for new pipelines in areas prone to ground movement has evolved over the last 10 years from a stress-based design approach to a strain-based design (SBD) approach to further realize the cost benefits from using higher strength linepipe steels. This report presents an overview of SBD for pipelines subjected to large longitudinal strain and high internal pressure with emphasis on the tensile strain capacity of high-strength microalloyed linepipe steel. The technical basis for this report involved engineering analysis and examination of the mechanical behavior of Grade X80 linepipe steel in both the longitudinal and circumferential directions. Testing was conducted to assess effects on material processing including as-rolled, expanded, and heat treatment processing intended to simulate coating application. Elastic-plastic and low-cycle fatigue analyses were also performed with varying internal pressures. Proposed SBD models discussed in this report are based on classical plasticity theory and account for material anisotropy, triaxial strain, and microstructural damage effects

  17. Large-Scale Renewable Energy Guide Webinar

    Broader source: Energy.gov [DOE]

    Webinar introduces the “Large Scale Renewable Energy Guide." The webinar will provide an overview of this important FEMP guide, which describes FEMP's approach to large-scale renewable energy projects and provides guidance to Federal agencies and the private sector on how to develop a common process for large-scale renewable projects.

  18. Using Multispectral Imaging to Measure Temperature Profiles and Emissivity of Large Thermionic Dispenser, Cathodes

    SciTech Connect (OSTI)

    D.F. Simmons; C.M. Fortgang; D.B. Holtkamp

    2001-09-01

    Thermionic dispenser cathodes are widely used in modern high-power microwave tubes. Use of these cathodes has led to significant improvement in performance. In recent years these cathodes have been used in electron linear accelerators (LINACs), particularly in induction LINACs, such as the Experimental Test Accelerator at Lawrence Livermore National Laboratory and the Relativistic Test Accelerator at Lawrence Berkeley National Laboratory. For induction LINACs, the thermionic dispenser cathode provides greater reproducibility, longer pulse lengths, and lower emittance beams than does a field emission cathode. Los Alamos National Laboratory is fabricating a dual-axis X-ray radiography machine called dual-axis radiograph hydrodynamic test (DARHT). The second axis of DARHT consists of a 2-kA, 20-MeV induction LINAC that uses a 3.2-MeV electron gun with a tungsten thermionic-dispenser cathode. Typically the DARHT cathode current density is 10 A/cm{sup 2} at 1050 C. Under these conditions current density is space-charge limited, which is desirable since current density is independent of temperature. At lower temperature (the temperature-limited regime) there are variations in the local current density due to a nonuniform temperature profile. To obtain the desired uniform current density associated with space-charge limited operation, the coolest area on the cathode must be at a sufficiently high temperature so that the emission is space-charge limited. Consequently, the rest of the cathode is emitting at the same space-charge-limited current density but is at a higher temperature than necessary. Because cathode lifetime is such a strong function of cathode temperature, there is a severe penalty for nonuniformity in the cathode temperature. For example, a temperature increase of 50 C means cathode lifetime will decrease by a factor of at least four. Therefore, we are motivated to measure the temperature profiles of our large-area cathodes.

  19. Large-Scale PCA for Climate

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

    Large-Scale PCA for Climate Large-Scale PCA for Climate The most widely used tool for extracting important patterns from the measurements of atmospheric and oceanic variables is the Empirical Orthogonal Function (EOF) technique. EOFs are popular because of their simplicity and their ability to reduce the dimensionality of large nonlinear, high-dimensional systems into fewer dimensions while preserving the most important patterns of variations in the measurements. Because EOFs are a particular

  20. Idaho Power- Large Commercial Custom Efficiency Program

    Broader source: Energy.gov [DOE]

    Large commercial and industrial Idaho Power customers that reduce energy usage through more efficient electrical commercial and industrial processes may qualify for an incentive that is the lesser...

  1. Final Report - Improved Large Aperture Collector Manufacturing...

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

    Final Report - Improved Large Aperture Collector Manufacturing Awardee: Abengoa Solar Location: Lakewood, CO Subprogram: Concentrating Solar Power, Technology to Market Funding ...

  2. The Cielo Petascale Capability Supercomputer: Providing Large...

    Office of Scientific and Technical Information (OSTI)

    Title: The Cielo Petascale Capability Supercomputer: Providing Large-Scale Computing for Stockpile Stewardship Authors: Vigil, Benny Manuel 1 ; Doerfler, Douglas W. 1 + Show ...

  3. Large Eddy Simulation (LES) of Engines

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

    Reacting FlowModelingLarge Eddy Simulation (LES) of ... The integrated set of tasks provides an optimal combination ... models for a variety of propulsion and power devices

  4. Generically large nongaussianity in small multifield inflation

    SciTech Connect (OSTI)

    Bramante, Joseph

    2015-07-07

    If forthcoming measurements of cosmic photon polarization restrict the primordial tensor-to-scalar ratio to r<0.01, small field inflation will be a principal candidate for the origin of the universe. Here we show that small multifield inflation, without the hybrid mechanism, typically results in large squeezed nongaussianity. Small multifield potentials contain multiple flat field directions, often identified with the gauge invariant field directions in supersymmetric potentials. We find that unless these field directions have equal slopes, large nongaussianity arises. After identifying relevant differences between large and small two-field potentials, we demonstrate that the latter naturally fulfill the Byrnes-Choi-Hall large nongaussianity conditions. Computations of the primordial power spectrum, spectral index, and squeezed bispectrum, reveal that small two-field models which otherwise match observed primordial perturbations, produce excludably large nongaussianity if the inflatons’ field directions have unequal slopes.

  5. High Fidelity Simulations of Large-Scale Wireless Networks (Plus-Up)

    SciTech Connect (OSTI)

    Onunkwo, Uzoma

    2015-11-01

    Sandia has built a strong reputation in scalable network simulation and emulation for cyber security studies to protect our nation’s critical information infrastructures. Georgia Tech has preeminent reputation in academia for excellence in scalable discrete event simulations, with strong emphasis on simulating cyber networks. Many of the experts in this field, such as Dr. Richard Fujimoto, Dr. George Riley, and Dr. Chris Carothers, have strong affiliations with Georgia Tech. The collaborative relationship that we intend to immediately pursue is in high fidelity simulations of practical large-scale wireless networks using ns-3 simulator via Dr. George Riley. This project will have mutual benefits in bolstering both institutions’ expertise and reputation in the field of scalable simulation for cyber-security studies. This project promises to address high fidelity simulations of large-scale wireless networks. This proposed collaboration is directly in line with Georgia Tech’s goals for developing and expanding the Communications Systems Center, the Georgia Tech Broadband Institute, and Georgia Tech Information Security Center along with its yearly Emerging Cyber Threats Report. At Sandia, this work benefits the defense systems and assessment area with promise for large-scale assessment of cyber security needs and vulnerabilities of our nation’s critical cyber infrastructures exposed to wireless communications.

  6. Large Eddy Simulation (LES) of Engines

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

    Engine Combustion/Modeling/Large Eddy Simulation (LES) of Engines Large Eddy Simulation (LES) of Engines admin 2015-10-28T02:19:26+00:00 LES-SN-LES-Eng-Combustion-Modeling-2 The combination of High Performance Computing (HPC) and the Large Eddy Simulation (LES) technique has significant potential to provide new insights into the dynamics of IC-engine flow processes. At the CRF, we integrate the combined merits of HPC and LES in a manner that provides some of the highest-fidelity, most detailed

  7. Large Eddy Simulation (LES) of Engines

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

    Reacting Flow/Modeling/Large Eddy Simulation (LES) of Engines Large Eddy Simulation (LES) of Engines admin 2015-10-30T01:57:44+00:00 The combination of high-performance computing (HPC) and the large eddy simulation (LES) technique has significant potential to provide new insights into the dynamics of many types of turbulent combustion processes. The objective of LES development at the CRF is to fully integrate the combined merits of HPC and LES in a manner that provides some of the

  8. Very Large System Dynamics Models - Lessons Learned

    SciTech Connect (OSTI)

    Jacob J. Jacobson; Leonard Malczynski

    2008-10-01

    This paper provides lessons learned from developing several large system dynamics (SD) models. System dynamics modeling practice emphasize the need to keep models small so that they are manageable and understandable. This practice is generally reasonable and prudent; however, there are times that large SD models are necessary. This paper outlines two large SD projects that were done at two Department of Energy National Laboratories, the Idaho National Laboratory and Sandia National Laboratories. This paper summarizes the models and then discusses some of the valuable lessons learned during these two modeling efforts.

  9. Large-Scale Wind Training Program

    SciTech Connect (OSTI)

    Porter, Richard L.

    2013-07-01

    Project objective is to develop a credit-bearing wind technician program and a non-credit safety training program, train faculty, and purchase/install large wind training equipment.

  10. large-point | netl.doe.gov

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

    Carbon Dioxide Capture from Large Point Sources Project No.: FG02-04ER83925 SBIR Commercial hollow fiber membrane cartridge. Commercial hollow fiber membrane cartridge [6"(D) X 17"(L)]. (click on image to enlarge) Compact Membrane Systems, Inc. developed and tested a carbon dioxide (CO2) removal system for flue gas streams from large point sources that offers improved mass transfer rates compared to conventional technologies. The project fabricated perfluorinated membranes on

  11. Large-Scale Liquid Hydrogen Handling Equipment

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

    8, 2007 Jerry Gillette Large-Scale Liquid Hydrogen Handling Equipment Hydrogen Delivery Analysis Meeting Argonne National Laboratory Some Delivery Pathways Will Necessitate the Use of Large- Scale Liquid Hydrogen Handling Equipment „ Potential Scenarios include: - Production plant shutdowns - Summer-peak storage „ Equipment Needs include: - Storage tanks - Liquid Pumps - Vaporizers - Ancillaries 2 1 Concern is that Scaling up from Small Units Could Significantly Underestimate Costs of Larger

  12. Evaluation of dual energy quantitative CT for determining the spatial distributions of red marrow and bone for dosimetry in internal emitter radiation therapy

    SciTech Connect (OSTI)

    Goodsitt, Mitchell M. Shenoy, Apeksha; Howard, David; Christodoulou, Emmanuel; Dewaraja, Yuni K.; Shen, Jincheng; Schipper, Matthew J.; Wilderman, Scott; Chun, Se Young

    2014-05-15

    Purpose: To evaluate a three-equation three-unknown dual-energy quantitative CT (DEQCT) technique for determining region specific variations in bone spongiosa composition for improved red marrow dose estimation in radionuclide therapy. Methods: The DEQCT method was applied to 80/140 kVp images of patient-simulating lumbar sectional body phantoms of three sizes (small, medium, and large). External calibration rods of bone, red marrow, and fat-simulating materials were placed beneath the body phantoms. Similar internal calibration inserts were placed at vertebral locations within the body phantoms. Six test inserts of known volume fractions of bone, fat, and red marrow were also scanned. External-to-internal calibration correction factors were derived. The effects of body phantom size, radiation dose, spongiosa region segmentation granularity [single (∼17 × 17 mm) region of interest (ROI), 2 × 2, and 3 × 3 segmentation of that single ROI], and calibration method on the accuracy of the calculated volume fractions of red marrow (cellularity) and trabecular bone were evaluated. Results: For standard low dose DEQCT x-ray technique factors and the internal calibration method, the RMS errors of the estimated volume fractions of red marrow of the test inserts were 1.2–1.3 times greater in the medium body than in the small body phantom and 1.3–1.5 times greater in the large body than in the small body phantom. RMS errors of the calculated volume fractions of red marrow within 2 × 2 segmented subregions of the ROIs were 1.6–1.9 times greater than for no segmentation, and RMS errors for 3 × 3 segmented subregions were 2.3–2.7 times greater than those for no segmentation. Increasing the dose by a factor of 2 reduced the RMS errors of all constituent volume fractions by an average factor of 1.40 ± 0.29 for all segmentation schemes and body phantom sizes; increasing the dose by a factor of 4 reduced those RMS errors by an average factor of 1.71 ± 0.25. Results

  13. Utilizing the Inherent Electrolysis in a Chip-Based Nanoelectrospray Emitter System to Facilitate Selective Ionization and Mass Spectrometric Analysis of Metallo Alkylporphyrins

    SciTech Connect (OSTI)

    Van Berkel, Gary J; Kertesz, Vilmos

    2012-01-01

    A commercially available chip-based infusion nanoelectrospray ionization system was used to ionize metallo alkylporphyrins for mass spectrometric detection and structure elucidation by mass spectrometry. Different ionic forms of model compounds (nickel (II), vanadyl (II), copper (II) and cobalt (II) octaethylporphyrin) were created by using two different types of conductive pipette tips supplied with the device. These pipette tips provide the conductive contact to solution at which the electrolysis process inherent to electrospray takes places in the device. The original unmodified, bare carbon-impregnated plastic pipette tips, were exploited to intentionally electrochemically oxidize (ionize) the porphyrins to form molecular radical cations for detection. Use of modified pipette tips, with a surface coating devised to inhibit analyte mass transport to the surface, was shown to limit the ionic species observed in the mass spectra of these porphyrins largely, but not exclusively, to the protonated molecule. Under the conditions of these experiments, the effective upper potential limit for oxidation with the uncoated pipette tip was 1.1 V or less and the coated pipette tips effectively prevented the oxidation of analytes with redox potentials greater than about 0.25 V. Product ion spectra of either molecular ionic species could be used to determine the alkyl chain length on the porphyrin macrocycle. The utility of this electrochemical ionization approach for the analysis of naturally occurring samples was demonstrated using nickel geoporphyrin fractions isolated from Gilsonite bitumen. Acquiring neutral loss spectra as a means to improve the specificity of detection in these complex natural samples was also illustrated.

  14. Comparing large scale CCS deployment potential in the USA and China: a detailed analysis based on country-specific CO2 transport & storage cost curves

    SciTech Connect (OSTI)

    Dahowski, Robert T.; Davidson, Casie L.; Dooley, James J.

    2011-04-18

    The United States and China are the two largest emitters of greenhouse gases in the world and their projected continued growth and reliance on fossil fuels, especially coal, make them strong candidates for CCS. Previous work has revealed that both nations have over 1600 large electric utility and other industrial point CO2 sources as well as very large CO2 storage resources on the order of 2,000 billion metric tons (Gt) of onshore storage capacity. In each case, the vast majority of this capacity is found in deep saline formations. In both the USA and China, candidate storage reservoirs are likely to be accessible by most sources with over 80% of these large industrial CO2 sources having a CO2 storage option within just 80 km. This suggests a strong potential for CCS deployment as a meaningful option to efforts to reduce CO2 emissions from these large, vibrant economies. However, while the USA and China possess many similarities with regards to the potential value that CCS might provide, including the range of costs at which CCS may be available to most large CO2 sources in each nation, there are a number of more subtle differences that may help us to understand the ways in which CCS deployment may differ between these two countries in order for the USA and China to work together - and in step with the rest of the world - to most efficiently reduce greenhouse gas emissions. This paper details the first ever analysis of CCS deployment costs in these two countries based on methodologically comparable CO2 source and sink inventories, economic analysis, geospatial source-sink matching and cost curve modeling. This type of analysis provides a valuable insight into the degree to which early and sustained opportunities for climate change mitigation via commercial-scale CCS are available to the two countries, and could facilitate greater collaboration in areas where those opportunities overlap.

  15. Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider

    SciTech Connect (OSTI)

    Bruce, R.; Blaskiewicz, M.; Jowett, J.M.; Fischer, W.

    2010-09-07

    We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon {sup 197}Au{sup 79}+ beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both methods to make predictions of the time evolution of the future {sup 208}Pb+{sup 82+} beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

  16. LARGE INDUSTRIAL FACILITIES BY STATE | Department of Energy

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

    LARGE INDUSTRIAL FACILITIES BY STATE LARGE INDUSTRIAL FACILITIES BY STATE PDF icon Number of Large Energy User Manufacturing Facilities by Sector and State (with Industrial Energy...

  17. Sandia Energy - Large Eddy Simulation (LES) of Engines

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

    Large Eddy Simulation (LES) of Engines Home Transportation Energy Predictive Simulation of Engines Engine Combustion Modeling Large Eddy Simulation (LES) of Engines Large Eddy...

  18. Large volume flow-through scintillating detector

    DOE Patents [OSTI]

    Gritzo, Russ E.; Fowler, Malcolm M.

    1995-01-01

    A large volume flow through radiation detector for use in large air flow situations such as incinerator stacks or building air systems comprises a plurality of flat plates made of a scintillating material arranged parallel to the air flow. Each scintillating plate has a light guide attached which transfers light generated inside the scintillating plate to an associated photomultiplier tube. The output of the photomultiplier tubes are connected to electronics which can record any radiation and provide an alarm if appropriate for the application.

  19. Method and apparatus for extruding large honeycombs

    DOE Patents [OSTI]

    Kragle, Harry A.; Lambert, David W.; Lipp, G. Daniel

    1996-09-03

    Extrusion die apparatus and an extrusion method for extruding large-cross-section honeycomb structures from plasticized ceramic batch materials are described, the apparatus comprising a die having a support rod connected to its central portion, the support rod being anchored to support means upstream of the die. The support rod and support means act to limit die distortion during extrusion, reducing die strain and stress to levels permitting large honeycomb extrusion without die failure. Dies of optimal thickness are disclosed which reduce the maximum stresses exerted on the die during extrusion.

  20. Energy Department Intends to Issue Funding Opportunity Announcement...

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

    primary feedstocks could offer energy savings on the order of 1.6 quadrillion BTU (quads) annually across four classes of waste materials - metals, fibers, polymers, and e-waste. ...

  1. Project Profile: Improved Large Aperture Collector Manufacturing

    Broader source: Energy.gov [DOE]

    Abengoa Solar, under the Solar Manufacturing Technology (SolarMat) program, will be investigating the use of an automotive-style high-rate fabrication and automated assembly techniques to achieve a substantial reduction in the deployment cost of their new SpaceTube advanced large aperture parabolic trough collector.

  2. Aerodynamic beam generator for large particles

    DOE Patents [OSTI]

    Brockmann, John E. (Albuquerque, NM); Torczynski, John R. (Albuquerque, NM); Dykhuizen, Ronald C. (Albuquerque, NM); Neiser, Richard A. (Albuquerque, NM); Smith, Mark F. (Albuquerque, NM)

    2002-01-01

    A new type of aerodynamic particle beam generator is disclosed. This generator produces a tightly focused beam of large material particles at velocities ranging from a few feet per second to supersonic speeds, depending on the exact configuration and operating conditions. Such generators are of particular interest for use in additive fabrication techniques.

  3. Global Alignment System for Large Genomic Sequencing

    Energy Science and Technology Software Center (OSTI)

    2002-03-01

    AVID is a global alignment system tailored for the alignment of large genomic sequences up to megabases in length. Features include the possibility of one sequence being in draft form, fast alignment, robustness and accuracy. The method is an anchor based alignment using maximal matches derived from suffix trees.

  4. Analysis of large soil samples for actinides

    DOE Patents [OSTI]

    Maxwell, III; Sherrod L.

    2009-03-24

    A method of analyzing relatively large soil samples for actinides by employing a separation process that includes cerium fluoride precipitation for removing the soil matrix and precipitates plutonium, americium, and curium with cerium and hydrofluoric acid followed by separating these actinides using chromatography cartridges.

  5. Modeling needs for very large systems.

    SciTech Connect (OSTI)

    Stein, Joshua S.

    2010-10-01

    Most system performance models assume a point measurement for irradiance and that, except for the impact of shading from nearby obstacles, incident irradiance is uniform across the array. Module temperature is also assumed to be uniform across the array. For small arrays and hourly-averaged simulations, this may be a reasonable assumption. Stein is conducting research to characterize variability in large systems and to develop models that can better accommodate large system factors. In large, multi-MW arrays, passing clouds may block sunlight from a portion of the array but never affect another portion. Figure 22 shows that two irradiance measurements at opposite ends of a multi-MW PV plant appear to have similar irradiance (left), but in fact the irradiance is not always the same (right). Module temperature may also vary across the array, with modules on the edges being cooler because they have greater wind exposure. Large arrays will also have long wire runs and will be subject to associated losses. Soiling patterns may also vary, with modules closer to the source of soiling, such as an agricultural field, receiving more dust load. One of the primary concerns associated with this effort is how to work with integrators to gain access to better and more comprehensive data for model development and validation.

  6. Buried pipelines in large fault movements

    SciTech Connect (OSTI)

    Wang, L.J.; Wang, L.R.L.

    1995-12-31

    Responses of buried pipelines in large fault movements are examined based upon a non-linear cantilever beam analogy. This analogy assumes that the pipeline in a large deflection zone behaves like a cantilever beam under a transverse-concentrated shear at the inflection point with a uniformly distributed soil pressure along the entire span. The tangent modulus approach is adopted to analyze the coupled axial force-bending moment interaction on pipeline deformations in the inelastic range. The buckling load of compressive pipeline is computed by the modified Newmark`s numerical integration scheme. Parametric studies of both tensile and compressive pipeline responses to various fault movements, pipeline/fault crossing angles, soil/pipe friction angles, buried depths, pipe diameters and thickness are investigated. It is shown by the comparisons that previous findings were unconservative.

  7. Passive load control for large wind turbines.

    SciTech Connect (OSTI)

    Ashwill, Thomas D.

    2010-05-01

    Wind energy research activities at Sandia National Laboratories focus on developing large rotors that are lighter and more cost-effective than those designed with current technologies. Because gravity scales as the cube of the blade length, gravity loads become a constraining design factor for very large blades. Efforts to passively reduce turbulent loading has shown significant potential to reduce blade weight and capture more energy. Research in passive load reduction for wind turbines began at Sandia in the late 1990's and has moved from analytical studies to blade applications. This paper discusses the test results of two Sandia prototype research blades that incorporate load reduction techniques. The TX-100 is a 9-m long blade that induces bend-twist coupling with the use of off-axis carbon in the skin. The STAR blade is a 27-m long blade that induces bend-twist coupling by sweeping the blade in a geometric fashion.

  8. Electronic and chemical structure of an organic light emitter embedded in an inorganic wide-bandgap semiconductor: Photoelectron spectroscopy of layered and composite structures of Ir(BPA) and ZnSe

    SciTech Connect (OSTI)

    Dimamay, Mariel; Mayer, Thomas; Jaegermann, Wolfram; Hadziioannou, Georges

    2015-05-07

    Luminescent organic phases embedded in conductive inorganic matrices are proposed for hybrid organic-inorganic light-emitting diodes. In this configuration, the organic dye acts as the radiative recombination site for charge carriers injected into the inorganic matrix. Our investigation is aimed at finding a material combination where the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of the organic dye are situated in between the valence and conduction bands of the inorganic matrix in order to promote electron and hole transfer from the matrix to the dye. Bilayer and composite thin films of zinc selenide (ZnSe) and a red iridium complex (Ir(BPA)) organic light emitter were prepared in situ via UHV thermal evaporation technique. The electronic and atomic structures were studied applying X-ray and ultraviolet photoelectron spectroscopies. The measured energy band alignments for the ZnSe/Ir(BPA) bilayer and ZnSe+Ir(BPA) composite reveal that the HOMO and LUMO of the organic dye are positioned in the ZnSe bandgap. For the initial steps of ZnSe deposition on a dye film to form Ir(BPA)/ZnSe bilayers, zinc atoms intercalate into the dye film leaving behind an excess of selenium at the interface that partly reacts with dye molecules. Photoelectron spectroscopy of the composites shows the same species suggesting a similar mechanism. This mechanism leads to composite films with increased content of amorphous phases in the inorganic matrix, thereby affecting its conductivity, as well as to the presence of nonradiative recombination sites provided by the intercalated Zn atoms.

  9. Large rectification in molecular heterojunctions | Argonne National

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

    Laboratory Large rectification in molecular heterojunctions April 19, 2016 Tweet EmailPrint The outstanding challenge in using molecules in optoelectronics devices is to create electrical functionality through molecular design and to go beyond the use of molecules as mere light absorbers and/or resistive elements. The earliest proposal for such non-linear electrical behavior is the Aviram-Ratner molecular diode model, proposed in 1974. However, more than forty years later, the electrical

  10. Large-Scale Computational Fluid Dynamics

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

    Large-Scale Computational Fluid Dynamics - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management

  11. motion-of-large-riprap-rocks

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

    Development of a Computational Approach to Detect Instability and Incipient Motion of Large Riprap Rocks" Presentation at the Transportation Research Board Annual Meeting Washington DC, January 14, 2014 Paper number 14-3035 Cezary Bojanowski Transportation Research and Analysis Computing Center (TRACC), Energy Systems Division Argonne National Laboratory Steven Lottes Transportation Research and Analysis Computing Center (TRACC), Energy Systems Division Argonne National Laboratory Abstract

  12. Large-Angle Anomalies in the CMB

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

    Copi, Craig J.; Huterer, Dragan; Schwarz, Dominik J.; Starkman, Glenn D.

    2010-01-01

    We review the recently found large-scale anomalies in the maps of temperature anisotropies in the cosmic microwave background. These include alignments of the largest modes of CMB anisotropy with each other and with geometry and direction of motion of the solar ssystem, and the unusually low power at these largest scales. We discuss these findings in relation to expectation from standard inflationary cosmology, their statistical significance, the tools to study them, and the various attempts to explain them.

  13. How large is 'large N{sub c}' for nuclear matter?

    SciTech Connect (OSTI)

    Torrieri, G. Mishustin, I.

    2012-06-15

    We argue that a so far neglected dimensionless scale, the number of neighbors in a closely packed system, is relevant for the convergence of the large-N{sub c} expansion at high chemical potential. It is only when the number of colors is large w.r.t. this new scale ({approx} O(10)) that a convergent large-N{sub c} limit is reached. This provides an explanation as to why the large-N{sub c} expansion, qualitatively successful in vacuum QCD, fails to describe high baryo-chemical potential systems, such as nuclear matter. It also means that phenomenological claims about high-density matter based on large-N{sub c} extrapolations should be treated with caution. This work is based on [1].

  14. Flexible Language Constructs for Large Parallel Programs

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

    Rosing, Matt; Schnabel, Robert

    1994-01-01

    The goal of the research described in this article is to develop flexible language constructs for writing large data parallel numerical programs for distributed memory (multiple instruction multiple data [MIMD]) multiprocessors. Previously, several models have been developed to support synchronization and communication. Models for global synchronization include single instruction multiple data (SIMD), single program multiple data (SPMD), and sequential programs annotated with data distribution statements. The two primary models for communication include implicit communication based on shared memory and explicit communication based on messages. None of these models by themselves seem sufficient to permit the natural and efficient expression ofmore » the variety of algorithms that occur in large scientific computations. In this article, we give an overview of a new language that combines many of these programming models in a clean manner. This is done in a modular fashion such that different models can be combined to support large programs. Within a module, the selection of a model depends on the algorithm and its efficiency requirements. In this article, we give an overview of the language and discuss some of the critical implementation details.« less

  15. Large Bore Powder Gun Qualification (U)

    SciTech Connect (OSTI)

    Rabern, Donald A.; Valdiviez, Robert

    2012-04-02

    A Large Bore Powder Gun (LBPG) is being designed to enable experimentalists to characterize material behavior outside the capabilities of the NNSS JASPER and LANL TA-55 PF-4 guns. The combination of these three guns will create a capability to conduct impact experiments over a wide range of pressures and shock profiles. The Large Bore Powder Gun will be fielded at the Nevada National Security Site (NNSS) U1a Complex. The Complex is nearly 1000 ft below ground with dedicated drifts for testing, instrumentation, and post-shot entombment. To ensure the reliability, safety, and performance of the LBPG, a qualification plan has been established and documented here. Requirements for the LBPG have been established and documented in WE-14-TR-0065 U A, Large Bore Powder Gun Customer Requirements. The document includes the requirements for the physics experiments, the gun and confinement systems, and operations at NNSS. A detailed description of the requirements is established in that document and is referred to and quoted throughout this document. Two Gun and Confinement Systems will be fielded. The Prototype Gun will be used primarily to characterize the gun and confinement performance and be the primary platform for qualification actions. This gun will also be used to investigate and qualify target and diagnostic modifications through the life of the program (U1a.104 Drift). An identical gun, the Physics Gun, will be fielded for confirmatory and Pu experiments (U1a.102D Drift). Both guns will be qualified for operation. The Gun and Confinement System design will be qualified through analysis, inspection, and testing using the Prototype Gun for the majority of process. The Physics Gun will be qualified through inspection and a limited number of qualification tests to ensure performance and behavior equivalent to the Prototype gun. Figure 1.1 shows the partial configuration of U1a and the locations of the Prototype and Physics Gun/Confinement Systems.

  16. Mass Estinctions Caused by Large Bolide Impacts

    SciTech Connect (OSTI)

    Lavarez, Luis W.

    1987-01-01

    In this talk, I will describe the wealth of evidence that has forced my colleagues and me to conclude that the great mass extinctions, 65 million years ago, were caused by a large bolide impact on the earth. Bolide is a new word to most people, and it means any piece of solar system debris, such as a meteorite, asteroid, or comet nucleus. As I will show, the bolide responsible for the extinction of most of the then existing species, including the dinosaurs, was about 10 kilometers in diameter.

  17. Method for large and rapid terahertz imaging

    DOE Patents [OSTI]

    Williams, Gwyn P.; Neil, George R.

    2013-01-29

    A method of large-scale active THz imaging using a combination of a compact high power THz source (>1 watt), an optional optical system, and a camera for the detection of reflected or transmitted THz radiation, without the need for the burdensome power source or detector cooling systems required by similar prior art such devices. With such a system, one is able to image, for example, a whole person in seconds or less, whereas at present, using low power sources and scanning techniques, it takes several minutes or even hours to image even a 1 cm.times.1 cm area of skin.

  18. Large-Scale PV Integration Study

    SciTech Connect (OSTI)

    Lu, Shuai; Etingov, Pavel V.; Diao, Ruisheng; Ma, Jian; Samaan, Nader A.; Makarov, Yuri V.; Guo, Xinxin; Hafen, Ryan P.; Jin, Chunlian; Kirkham, Harold; Shlatz, Eugene; Frantzis, Lisa; McClive, Timothy; Karlson, Gregory; Acharya, Dhruv; Ellis, Abraham; Stein, Joshua; Hansen, Clifford; Chadliev, Vladimir; Smart, Michael; Salgo, Richard; Sorensen, Rahn; Allen, Barbara; Idelchik, Boris

    2011-07-29

    This research effort evaluates the impact of large-scale photovoltaic (PV) and distributed generation (DG) output on NV Energy’s electric grid system in southern Nevada. It analyzes the ability of NV Energy’s generation to accommodate increasing amounts of utility-scale PV and DG, and the resulting cost of integrating variable renewable resources. The study was jointly funded by the United States Department of Energy and NV Energy, and conducted by a project team comprised of industry experts and research scientists from Navigant Consulting Inc., Sandia National Laboratories, Pacific Northwest National Laboratory and NV Energy.

  19. Massachusetts Large Blade Test Facility Final Report

    SciTech Connect (OSTI)

    Rahul Yarala; Rob Priore

    2011-09-02

    Project Objective: The Massachusetts Clean Energy Center (CEC) will design, construct, and ultimately have responsibility for the operation of the Large Wind Turbine Blade Test Facility, which is an advanced blade testing facility capable of testing wind turbine blades up to at least 90 meters in length on three test stands. Background: Wind turbine blade testing is required to meet international design standards, and is a critical factor in maintaining high levels of reliability and mitigating the technical and financial risk of deploying massproduced wind turbine models. Testing is also needed to identify specific blade design issues that may contribute to reduced wind turbine reliability and performance. Testing is also required to optimize aerodynamics, structural performance, encourage new technologies and materials development making wind even more competitive. The objective of this project is to accelerate the design and construction of a large wind blade testing facility capable of testing blades with minimum queue times at a reasonable cost. This testing facility will encourage and provide the opportunity for the U.S wind industry to conduct more rigorous testing of blades to improve wind turbine reliability.

  20. Diamond coated silicon field emitter array

    SciTech Connect (OSTI)

    S. Albin; W. Fu; A. Varghese; A. C. Lavarias; G. R. Myneni

    1999-07-01

    Diamond coated silicon tip arrays, with and without a self-aligned gate, were fabricated, and current-voltage characteristics of 400 tips were measured. Diamond films were grown uniformly on Si tips using microwave plasma after nucleation with 10 nm diamond suspension and substrate bias. An emission current of 57 ?A was obtained at 5 V from the ungated array tips separated from an anode at 2 ?m. In the case of the gated arrays with 1.5 ?m aperture, an emission current of 3.4 ?A was measured at a gate voltage of 80 V for an anode separation of 200 ?m. The turn-on voltages for these two types of devices were 0.2 and 40 V, respectively. Diamond coated Si tip arrays have potential applications in field emission based low voltage vacuum electronic devices and microsensors.

  1. Transverse Emittance Reduction with Tapered Foil (Conference...

    Office of Scientific and Technical Information (OSTI)

    In this paper, we build a more complete physical model of the tapered foil based on Ref. ... The contents of this paper are arranged as follows. In Sec. II, we build the physical ...

  2. Pair Creation at Large Inherent Angles

    SciTech Connect (OSTI)

    Chen, P.; Tauchi, T.; Schroeder, D.V.; /SLAC

    2007-04-25

    In the next-generation linear colliders, the low-energy e{sup +}e{sup -} pairs created during the collision of high-energy e{sup +}e{sup -} beams would cause potential deleterious background problems to the detectors. At low collider energies, the pairs are made essentially by the incoherent process, where the pair is created by the interaction of beamstrahlung photons on the individual particles in the oncoming beam. This problem was first identified by Zolotarev, et al[1]. At energies where the beamstrahlung parameter {Upsilon} lies approximately in the range 0.6 {approx}< {Upsilon} {approx}< 100, pair creation from the beamstrahlung photons is dominated by a coherent process, first noted by Chen[2]. The seriousness of this pair creation problem lies in the transverse momenta that the pair particles carry when leaving the interaction point (IP) with large angles. One source of transverse momentum is from the kick by the field of the oncoming beam which results in an outcoming angle {theta} {proportional_to} 1/{radical}x, where x is the fractional energy of the particle relative to the initial beam particle energy[2,3]. As was shown in Ref. 131, there in fact exists an energy threshold for the coherent pairs, where x{sub th} {approx}> 1/2{Upsilon}. Thus within a tolerable exiting angle, there exists an upper limit for {Upsilon} where all coherent pairs would leave the detector through the exhaust port[4]. A somewhat different analysis has been done by Schroeder[5]. In the next generation of linear colliders, as it occurs, the coherent pairs can be exponentially suppressed[2] by properly choosing the {Upsilon}({approx}< 0.6). When this is achieved, the incoherent pairs becomes dominant. Since the central issue is the transverse momentum for particles with large angles, we notice that there is another source for it. Namely, when the pair particles are created at low energies, the intrinsic angles of these pairs when produced may already be large. This issue was

  3. Highly-basic large-pore zeolite catalysts for NOx reduction at low temperatures

    DOE Patents [OSTI]

    Penetrante, Bernardino M.; Brusasco, Raymond M.; Merritt, Bernard T.; Vogtlin, George E.

    2004-02-03

    A high-surface-area (greater than 600 m2/g), large-pore (pore size diameter greater than 6.5 angstroms), basic zeolite having a structure such as an alkali metal cation-exchanged Y-zeolite is employed to convert NO.sub.x contained in an oxygen-rich engine exhaust to N.sub.2 and O.sub.2. Preferably, the invention relates to a two-stage method and apparatus for NO.sub.x reduction in an oxygen-rich engine exhaust such as diesel engine exhaust that includes a plasma oxidative stage and a selective reduction stage. The first stage employs a non-thermal plasma treatment of NO.sub.x gases in an oxygen-rich exhaust and is intended to convert NO to NO.sub.2 in the presence of O.sub.2 and added hydrocarbons. The second stage employs a lean-NO.sub.x catalyst including the basic zeolite at relatively low temperatures to convert such NO.sub.2 to environmentally benign gases that include N.sub.2, CO.sub.2, and H.sub.2 O.

  4. Large-Scale Renewable Energy Guide | Department of Energy

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

    Large-Scale Renewable Energy Guide Large-Scale Renewable Energy Guide Presentation covers the Large-scale RE Guide: Developing Renewable Energy Projects Larger than 10 MWs at...

  5. System for inspecting large size structural components

    DOE Patents [OSTI]

    Birks, Albert S. (Columbus, OH); Skorpik, James R. (Kennewick, WA)

    1990-01-01

    The present invention relates to a system for inspecting large scale structural components such as concrete walls or the like. The system includes a mobile gamma radiation source and a mobile gamma radiation detector. The source and detector are constructed and arranged for simultaneous movement along parallel paths in alignment with one another on opposite sides of a structural component being inspected. A control system provides signals which coordinate the movements of the source and detector and receives and records the radiation level data developed by the detector as a function of source and detector positions. The radiation level data is then analyzed to identify areas containing defects corresponding to unexpected variations in the radiation levels detected.

  6. Meteorological aspects of siting large wind turbines

    SciTech Connect (OSTI)

    Hiester, T.R.; Pennell, W.T.

    1981-01-01

    This report, which focuses on the meteorological aspects of siting large wind turbines (turbines with a rated output exceeding 100 kW), has four main goals. The first is to outline the elements of a siting strategy that will identify the most favorable wind energy sites in a region and that will provide sufficient wind data to make responsible economic evaluations of the site wind resource possible. The second is to critique and summarize siting techniques that were studied in the Department of Energy (DOE) Wind Energy Program. The third goal is to educate utility technical personnel, engineering consultants, and meteorological consultants (who may have not yet undertaken wind energy consulting) on meteorological phenomena relevant to wind turbine siting in order to enhance dialogues between these groups. The fourth goal is to minimize the chances of failure of early siting programs due to insufficient understanding of wind behavior.

  7. Batteries for Large Scale Energy Storage

    SciTech Connect (OSTI)

    Soloveichik, Grigorii L.

    2011-07-15

    In recent years, with the deployment of renewable energy sources, advances in electrified transportation, and development in smart grids, the markets for large-scale stationary energy storage have grown rapidly. Electrochemical energy storage methods are strong candidate solutions due to their high energy density, flexibility, and scalability. This review provides an overview of mature and emerging technologies for secondary and redox flow batteries. New developments in the chemistry of secondary and flow batteries as well as regenerative fuel cells are also considered. Advantages and disadvantages of current and prospective electrochemical energy storage options are discussed. The most promising technologies in the short term are high-temperature sodium batteries with β”-alumina electrolyte, lithium-ion batteries, and flow batteries. Regenerative fuel cells and lithium metal batteries with high energy density require further research to become practical.

  8. (Sparsity in large scale scientific computation)

    SciTech Connect (OSTI)

    Ng, E.G.

    1990-08-20

    The traveler attended a conference organized by the 1990 IBM Europe Institute at Oberlech, Austria. The theme of the conference was on sparsity in large scale scientific computation. The conference featured many presentations and other activities of direct interest to ORNL research programs on sparse matrix computations and parallel computing, which are funded by the Applied Mathematical Sciences Subprogram of the DOE Office of Energy Research. The traveler presented a talk on his work at ORNL on the development of efficient algorithms for solving sparse nonsymmetric systems of linear equations. The traveler held numerous technical discussions on issues having direct relevance to the research programs on sparse matrix computations and parallel computing at ORNL.

  9. Storage and retrieval of large digital images

    DOE Patents [OSTI]

    Bradley, Jonathan N.

    1998-01-01

    Image compression and viewing are implemented with (1) a method for performing DWT-based compression on a large digital image with a computer system possessing a two-level system of memory and (2) a method for selectively viewing areas of the image from its compressed representation at multiple resolutions and, if desired, in a client-server environment. The compression of a large digital image I(x,y) is accomplished by first defining a plurality of discrete tile image data subsets T.sub.ij (x,y) that, upon superposition, form the complete set of image data I(x,y). A seamless wavelet-based compression process is effected on I(x,y) that is comprised of successively inputting the tiles T.sub.ij (x,y) in a selected sequence to a DWT routine, and storing the resulting DWT coefficients in a first primary memory. These coefficients are periodically compressed and transferred to a secondary memory to maintain sufficient memory in the primary memory for data processing. The sequence of DWT operations on the tiles T.sub.ij (x,y) effectively calculates a seamless DWT of I(x,y). Data retrieval consists of specifying a resolution and a region of I(x,y) for display. The subset of stored DWT coefficients corresponding to each requested scene is determined and then decompressed for input to an inverse DWT, the output of which forms the image display. The repeated process whereby image views are specified may take the form an interaction with a computer pointing device on an image display from a previous retrieval.

  10. Storage and retrieval of large digital images

    DOE Patents [OSTI]

    Bradley, J.N.

    1998-01-20

    Image compression and viewing are implemented with (1) a method for performing DWT-based compression on a large digital image with a computer system possessing a two-level system of memory and (2) a method for selectively viewing areas of the image from its compressed representation at multiple resolutions and, if desired, in a client-server environment. The compression of a large digital image I(x,y) is accomplished by first defining a plurality of discrete tile image data subsets T{sub ij}(x,y) that, upon superposition, form the complete set of image data I(x,y). A seamless wavelet-based compression process is effected on I(x,y) that is comprised of successively inputting the tiles T{sub ij}(x,y) in a selected sequence to a DWT routine, and storing the resulting DWT coefficients in a first primary memory. These coefficients are periodically compressed and transferred to a secondary memory to maintain sufficient memory in the primary memory for data processing. The sequence of DWT operations on the tiles T{sub ij}(x,y) effectively calculates a seamless DWT of I(x,y). Data retrieval consists of specifying a resolution and a region of I(x,y) for display. The subset of stored DWT coefficients corresponding to each requested scene is determined and then decompressed for input to an inverse DWT, the output of which forms the image display. The repeated process whereby image views are specified may take the form an interaction with a computer pointing device on an image display from a previous retrieval. 6 figs.

  11. Supporting large-scale computational science

    SciTech Connect (OSTI)

    Musick, R., LLNL

    1998-02-19

    Business needs have driven the development of commercial database systems since their inception. As a result, there has been a strong focus on supporting many users, minimizing the potential corruption or loss of data, and maximizing performance metrics like transactions per second, or TPC-C and TPC-D results. It turns out that these optimizations have little to do with the needs of the scientific community, and in particular have little impact on improving the management and use of large-scale high-dimensional data. At the same time, there is an unanswered need in the scientific community for many of the benefits offered by a robust DBMS. For example, tying an ad-hoc query language such as SQL together with a visualization toolkit would be a powerful enhancement to current capabilities. Unfortunately, there has been little emphasis or discussion in the VLDB community on this mismatch over the last decade. The goal of the paper is to identify the specific issues that need to be resolved before large-scale scientific applications can make use of DBMS products. This topic is addressed in the context of an evaluation of commercial DBMS technology applied to the exploration of data generated by the Department of Energy`s Accelerated Strategic Computing Initiative (ASCI). The paper describes the data being generated for ASCI as well as current capabilities for interacting with and exploring this data. The attraction of applying standard DBMS technology to this domain is discussed, as well as the technical and business issues that currently make this an infeasible solution.

  12. LIGHT CURVES OF 32 LARGE TRANSNEPTUNIAN OBJECTS

    SciTech Connect (OSTI)

    Benecchi, Susan D.; Sheppard, Scott S.

    2013-05-15

    We present observations of 32 primarily bright, newly discovered Transneptunian objects (TNOs) observable from the Southern Hemisphere during 39 nights of observation with the Irenee du Pont 2.5 m telescope at Las Campanas Observatory. Our dataset includes objects in all dynamical classes, but is weighted toward scattered objects. We find 15 objects for which we can fit periods and amplitudes to the data, and place light curve amplitude upper limits on the other 17 objects. Combining our sample with the larger light curve sample in the literature, we find a 3{sigma} correlation between light curve amplitude and absolute magnitude with fainter objects having larger light curve amplitudes. We looked for correlations between light curve and individual orbital properties, but did not find any statistically significant results. However, if we consider light curve properties with respect to object dynamical classification, we find statistically different distributions between the classical-scattered and classical-resonant populations at the 95.60% and 94.64% level, respectively, with the classical objects having larger amplitude light curves. The significance is 97.05% if the scattered and resonant populations are combined. The properties of binary light curves are largely consistent with the greater TNO population except in the case of tidally locked systems. All the Haumea family objects measured so far have light curve amplitudes and rotation periods {<=}10 hr, suggesting that they are not significantly different from the larger TNO population. We expect multiple factors are influencing object rotations: object size dominates light curve properties except in the case of tidal, or proportionally large collisional interactions with other TNOs, the influence of the latter being different for each TNO sub-population. We also present phase curves and colors for some of our objects.

  13. CHEMICAL EVOLUTION OF THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Bekki, Kenji [ICRAR, M468, University of Western Australia, 35 Stirling Highway, Crawley Western Australia 6009 (Australia); Tsujimoto, Takuji [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan)

    2012-12-20

    We adopt a new chemical evolution model for the Large Magellanic Cloud (LMC) and thereby investigate its past star formation and chemical enrichment histories. The delay time distribution of Type Ia supernovae recently revealed by Type Ia supernova surveys is incorporated self-consistently into the new model. The principle results are summarized as follows. The present gas mass fraction and stellar metallicity as well as the higher [Ba/Fe] in metal-poor stars at [Fe/H] < -1.5 can be more self-consistently explained by models with steeper initial mass functions. The observed higher [Mg/Fe] ({>=}0.3) at [Fe/H] {approx} -0.6 and higher [Ba/Fe] (>0.5) at [Fe/H] {approx} -0.3 could be due to significantly enhanced star formation about 2 Gyr ago. The observed overall [Ca/Fe]-[Fe/H] relation and remarkably low [Ca/Fe] (< - 0.2) at [Fe/H] > -0.6 are consistent with models with short-delay supernova Ia and with the more efficient loss of Ca possibly caused by an explosion mechanism of Type II supernovae. Although the metallicity distribution functions do not show double peaks in the models with a starburst about 2 Gyr ago, they show characteristic double peaks in the models with double starbursts {approx}200 Myr and {approx}2 Gyr ago. The observed apparent dip of [Fe/H] around {approx}1.5 Gyr ago in the age-metallicity relation can be reproduced by models in which a large amount ({approx}10{sup 9} M{sub Sun }) of metal-poor ([Fe/H] < -1) gas can be accreted onto the LMC.

  14. Optical Design for Extremely Large Telescope Adaptive Optics...

    Office of Scientific and Technical Information (OSTI)

    Large Telescope Adaptive Optics Systems Citation Details In-Document Search Title: Optical Design for Extremely Large Telescope Adaptive Optics Systems You are accessing a ...

  15. QER - Comment of Large Public Power Council 2 | Department of...

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

    Attached please find comments by the Large Public Power Council for the record regarding the April 11th QER meeting. Missy Mandell, Executive Director Large Public Power Council ...

  16. Stimulated forward Raman scattering in large scale-length laser...

    Office of Scientific and Technical Information (OSTI)

    Stimulated forward Raman scattering in large scale-length laser-produced plasmas Citation Details In-Document Search Title: Stimulated forward Raman scattering in large ...

  17. Optical Design for Extremely Large Telescope Adaptive Optics...

    Office of Scientific and Technical Information (OSTI)

    ThesisDissertation: Optical Design for Extremely Large Telescope Adaptive Optics Systems Citation Details In-Document Search Title: Optical Design for Extremely Large Telescope ...

  18. Vehicle Technologies Office Merit Review 2015: Large Eddy Simulation...

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

    Large Eddy Simulation (LES) Applied to Advanced Engine Combustion Research Vehicle Technologies Office Merit Review 2015: Large Eddy Simulation (LES) Applied to Advanced Engine ...

  19. Large-Scale Manufacturing of Nanoparticle-Based Lubrication Additives...

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

    Large-Scale Manufacturing of Nanoparticle-Based Lubrication Additives Large-Scale Manufacturing of Nanoparticle-Based Lubrication Additives PDF icon nanoparticulate-basedlubricati...

  20. Large Eddy Simulation (LES) Applied to Advanced Engine Combustion...

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

    Large Eddy Simulation (LES) Applied to Advanced Engine Combustion Research Large Eddy Simulation (LES) Applied to Low-Temperature and Diesel Engine Combustion Research Vehicle ...

  1. Creating Large Scale Database Servers (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Creating Large Scale Database Servers Citation Details In-Document Search Title: Creating Large Scale Database Servers The BaBar experiment at the Stanford Linear Accelerator ...

  2. DOE's New Large Blade Test Facility in Massachusetts Completes...

    Office of Environmental Management (EM)

    DOE's New Large Blade Test Facility in Massachusetts Completes First Commercial Blade Tests DOE's New Large Blade Test Facility in Massachusetts Completes First Commercial Blade ...

  3. DOE Issues Enforcement Guidance on Large-Capacity Clothes Washer...

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

    Enforcement Guidance on Large-Capacity Clothes Washer Waivers and the Waiver Process DOE Issues Enforcement Guidance on Large-Capacity Clothes Washer Waivers and the Waiver Process...

  4. Rapid Software Prototyping Into Large Scale Control Systems ...

    Office of Scientific and Technical Information (OSTI)

    Rapid Software Prototyping Into Large Scale Control Systems Citation Details In-Document Search Title: Rapid Software Prototyping Into Large Scale Control Systems Authors: Fishler, ...

  5. Large Higgs energy region in Higgs associated top pair production...

    Office of Scientific and Technical Information (OSTI)

    Large Higgs energy region in Higgs associated top pair production at the Linear Collider Citation Details In-Document Search Title: Large Higgs energy region in Higgs associated ...

  6. Large kinetic asymmetry in the metal-insulator transition nucleated...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Large kinetic asymmetry in the metal-insulator transition nucleated at localized and extended defects Citation Details In-Document Search Title: Large kinetic...

  7. Determination of Large-Scale Cloud Ice Water Concentration by...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Determination of Large-Scale Cloud Ice Water Concentration by Combining ... Title: Determination of Large-Scale Cloud Ice Water Concentration by Combining Surface ...

  8. Large-Scale Renewable Energy Guide: Developing Renewable Energy...

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

    Large-Scale Renewable Energy Guide: Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities Large-Scale Renewable Energy Guide: Developing Renewable Energy ...

  9. Large Scale Production Computing and Storage Requirements for...

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

    Large Scale Production Computing and Storage Requirements for Fusion Energy Sciences: Target 2017 The NERSC Program Requirements Review "Large Scale Production Computing and ...

  10. Large-Scale Residential Energy Efficiency Programs Based on CFLs...

    Open Energy Info (EERE)

    Large-Scale Residential Energy Efficiency Programs Based on CFLs Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Large-Scale Residential Energy Efficiency Programs Based...

  11. The Effective Field Theory of Cosmological Large Scale Structures...

    Office of Scientific and Technical Information (OSTI)

    The Effective Field Theory of Cosmological Large Scale Structures Citation Details In-Document Search Title: The Effective Field Theory of Cosmological Large Scale Structures...

  12. ACCOLADES: A Scalable Workflow Framework for Large-Scale Simulation...

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

    ACCOLADES: A Scalable Workflow Framework for Large-Scale Simulation and Analyses of Automotive Engines Title ACCOLADES: A Scalable Workflow Framework for Large-Scale Simulation and...

  13. Large Non-Gaussianity in Axion Inflation (Journal Article) |...

    Office of Scientific and Technical Information (OSTI)

    Large Non-Gaussianity in Axion Inflation Citation Details In-Document Search Title: Large Non-Gaussianity in Axion Inflation Authors: Barnaby, Neil ; Peloso, Marco Publication ...

  14. Surprisingly Large Generation and Retention of Helium and Hydrogen...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Surprisingly Large Generation and Retention of Helium and Hydrogen in ... Title: Surprisingly Large Generation and Retention of Helium and Hydrogen in Pure Nickel ...

  15. DLFM library tools for large scale dynamic applications

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

    applications DLFM library tools for large scale dynamic applications Large scale Python and other dynamic applications may spend huge time at startup. The DLFM library,...

  16. Airbrushed Nickel Nanoparticles for Large-Area (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Airbrushed Nickel Nanoparticles for Large-Area Citation Details In-Document Search Title: Airbrushed Nickel Nanoparticles for Large-Area Vertically aligned carbon nanofibers ...

  17. Montana's At-large congressional district: Energy Resources ...

    Open Energy Info (EERE)

    Registered Research Institutions in Montana's At-large congressional district Big Sky Carbon Sequestration Partnership Registered Energy Companies in Montana's At-large...

  18. Large Scale Computing and Storage Requirements for Advanced Scientific...

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

    Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research: Target 2014 ASCRFrontcover.png Large Scale Computing and Storage Requirements for ...

  19. Multifunctional, Inorganic-Filled Separators for Large Format...

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

    & Publications Multifunctional, Inorganic-Filled Separators for Large Format, Li-ion Batteries Multifunctional, Inorganic-Filled Separators for Large Format, Li-ion Batteries...

  20. Property:Building/SPElectrtyUsePercLargeComputersServers | Open...

    Open Energy Info (EERE)

    Jump to: navigation, search This is a property of type String. Large computers servers Pages using the property "BuildingSPElectrtyUsePercLargeComputersServers"...

  1. Building America Webinar: Opportunities in Large Data Collection...

    Energy Savers [EERE]

    Opportunities in Large Data Collection and Analysis Building America Webinar: Opportunities in Large Data Collection and Analysis The webinar, presented on April 16, 2014, focused ...

  2. Multiphoton ionization of large water clusters

    SciTech Connect (OSTI)

    Apicella, B.; Li, X.; Passaro, M.; Spinelli, N.; Wang, X.

    2014-05-28

    Water clusters are multimers of water molecules held together by hydrogen bonds. In the present work, multiphoton ionization in the UV range coupled with time of flight mass spectrometry has been applied to water clusters with up to 160 molecules in order to obtain information on the electronic states of clusters of different sizes up to dimensions that can approximate the bulk phase. The dependence of ion intensities of water clusters and their metastable fragments produced by laser ionization at 355 nm on laser power density indicates a (3+1)-photon resonance-enhanced multiphoton ionization process. It also explains the large increase of ionization efficiency at 355 nm compared to that at 266 nm. Indeed, it was found, by applying both nanosecond and picosecond laser ionization with the two different UV wavelengths, that no water cluster sequences after n = 9 could be observed at 266 nm, whereas water clusters up to m/z 2000 Th in reflectron mode and m/z 3000 Th in linear mode were detected at 355 nm. The agreement between our findings on clusters of water, especially true in the range with n > 10, and reported data for liquid water supports the hypothesis that clusters above a critical dimension can approximate the liquid phase. It should thus be possible to study clusters just above 10 water molecules, for getting information on the bulk phase structure.

  3. Airbrushed Nickel Nanoparticles for Large-Area

    SciTech Connect (OSTI)

    Sarac, Mehmet; ANDERSON, BRYAN; Pearce, Ryan; Railsback, Justin; Oni, Adedapo; White, Ryan M.; Hensley, Dale K; Lebeau, James M; Melechko, Anatoli; Tracy, Joseph B

    2013-01-01

    Vertically aligned carbon nanofibers (VACNFs) were grown by plasma-enhanced chemical vapor deposition (PECVD) using Ni nanoparticle (NP) catalysts that were deposited by airbrushing onto Si, Al, Cu, and Ti substrates. Airbrushing is a simple method for depositing catalyst NPs over large areas that is compatible with roll-to-roll processing. The distribution and morphology of VACNFs are affected by the airbrushing parameters and the composition of the metal foil. Highly concentrated Ni NPs in heptane give more uniform distributions than pentane and hexanes, resulting in more uniform coverage of VACNFs. For VACNF growth on metal foils, Si micropowder was added as a precursor for Si-enriched coatings formed in situ on the VACNFs that impart mechanical rigidity. Interactions between the catalyst NPs and the metal substrates impart control over the VACNF morphology. Growth of carbon nanostructures on Cu is particularly noteworthy because the miscibility of Ni with Cu poses challenges for VACNF growth, and carbon nanostructures anchored to Cu substrates are desired as anode materials for Li-ion batteries and for thermal interface materials.

  4. A large hadron electron collider at CERN

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

    Abelleira Fernandez, J. L.

    2015-04-06

    This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and eletron-ion physics. The LHeC is designed to run synchronously withmore » the LHC in the twenties and to achieve an integrated luminosity of O(100)fb–1. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC.« less

  5. Large magnetocapacitance in electronic ferroelectric manganite systems

    SciTech Connect (OSTI)

    Chowdhury, Ujjal; Goswami, Sudipta; Bhattacharya, Dipten; Midya, Arindam; Mandal, P.; Das, Pintu; Mukovskii, Ya. M.

    2013-11-21

    We have observed a sizable positive magnetocapacitance (?5%90%) in perovskite Pr{sub 0.55}Ca{sub 0.45}MnO{sub 3} and bilayer Pr(Sr{sub 0.1}Ca{sub 0.9}){sub 2}Mn{sub 2}O{sub 7} system under 5?T magnetic field across 20100?K below the magnetic transition point T{sub N}. The magnetodielectric effect, on the other hand, exhibits a crossover: (a) from positive to negative for the perovskite system and (b) from negative to positive for the bilayer system over the same temperature range. The bilayer Pr(Sr{sub 0.1}Ca{sub 0.9}){sub 2}Mn{sub 2}O{sub 7} system exhibits a sizable anisotropy as well. We have also noticed the influence of magnetic field on the dielectric relaxation characteristics of these systems. These systems belong to a class of improper ferroelectrics and are expected to exhibit charge/orbital order driven ferroelectric polarization below the transition point T{sub CO}. Large magnetocapacitance in these systems shows a typical multiferroic behavior even though the ferroelectric polarization is small in comparison to that of other ferroelectrics.

  6. Large optics for the National Ignition Facility

    SciTech Connect (OSTI)

    Baisden, P.

    2015-01-12

    The National Ignition Facility (NIF) laser with its 192 independent laser beams is not only the world’s largest laser, it is also the largest optical system ever built. With its 192 independent laser beams, the NIF requires a total of 7648 large-aperture (meter-sized) optics. One of the many challenges in designing and building NIF has been to carry out the research and development on optical materials, optics design, and optics manufacturing and metrology technologies needed to achieve NIF’s high output energies and precision beam quality. This paper describes the multiyear, multi-supplier, development effort that was undertaken to develop the advanced optical materials, coatings, fabrication technologies, and associated process improvements necessary to manufacture the wide range of NIF optics. The optics include neodymium-doped phosphate glass laser amplifiers; fused silica lenses, windows, and phase plates; mirrors and polarizers with multi-layer, high-reflectivity dielectric coatings deposited on BK7 substrates; and potassium di-hydrogen phosphate crystal optics for fast optical switches, frequency conversion, and polarization rotation. Also included is a discussion of optical specifications and custom metrology and quality-assurance tools designed, built, and fielded at supplier sites to verify compliance with the stringent NIF specifications. In addition, a brief description of the ongoing program to improve the operational lifetime (i.e., damage resistance) of optics exposed to high fluence in the 351-nm (3ω) is provided.

  7. A large hadron electron collider at CERN

    SciTech Connect (OSTI)

    Abelleira Fernandez, J. L.

    2015-04-06

    This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and eletron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100)fb1. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC.

  8. Large area atmospheric-pressure plasma jet

    DOE Patents [OSTI]

    Selwyn, Gary S.; Henins, Ivars; Babayan, Steve E.; Hicks, Robert F.

    2001-01-01

    Large area atmospheric-pressure plasma jet. A plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two planar, parallel electrodes are employed to generate a plasma in the volume therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly spacing the rf-powered electrode. Because of the atmospheric pressure operation, there is a negligible density of ions surviving for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike the situation for low-pressure plasma sources and conventional plasma processing methods.

  9. Large-scale quasi-geostrophic magnetohydrodynamics

    SciTech Connect (OSTI)

    Balk, Alexander M.

    2014-12-01

    We consider the ideal magnetohydrodynamics (MHD) of a shallow fluid layer on a rapidly rotating planet or star. The presence of a background toroidal magnetic field is assumed, and the 'shallow water' beta-plane approximation is used. We derive a single equation for the slow large length scale dynamics. The range of validity of this equation fits the MHD of the lighter fluid at the top of Earth's outer core. The form of this equation is similar to the quasi-geostrophic (Q-G) equation (for usual ocean or atmosphere), but the parameters are essentially different. Our equation also implies the inverse cascade; but contrary to the usual Q-G situation, the energy cascades to smaller length scales, while the enstrophy cascades to the larger scales. We find the Kolmogorov-type spectrum for the inverse cascade. The spectrum indicates the energy accumulation in larger scales. In addition to the energy and enstrophy, the obtained equation possesses an extra (adiabatic-type) invariant. Its presence implies energy accumulation in the 30° sector around zonal direction. With some special energy input, the extra invariant can lead to the accumulation of energy in zonal magnetic field; this happens if the input of the extra invariant is small, while the energy input is considerable.

  10. FERMI LARGE AREA TELESCOPE SECOND SOURCE CATALOG

    SciTech Connect (OSTI)

    Nolan, P. L.; Ajello, M.; Allafort, A.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Abdo, A. A.; Ackermann, M.; Antolini, E.; Bonamente, E.; Atwood, W. B.; Belfiore, A.; Axelsson, M.; Baldini, L.; Bellazzini, R.; Ballet, J.; Bastieri, D.; Bignami, G. F. E-mail: Gino.Tosti@pg.infn.it E-mail: tburnett@u.washington.edu; and others

    2012-04-01

    We present the second catalog of high-energy {gamma}-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), derived from data taken during the first 24 months of the science phase of the mission, which began on 2008 August 4. Source detection is based on the average flux over the 24 month period. The second Fermi-LAT catalog (2FGL) includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and spectral fits in terms of power-law, exponentially cutoff power-law, or log-normal forms. Also included are flux measurements in five energy bands and light curves on monthly intervals for each source. Twelve sources in the catalog are modeled as spatially extended. We provide a detailed comparison of the results from this catalog with those from the first Fermi-LAT catalog (1FGL). Although the diffuse Galactic and isotropic models used in the 2FGL analysis are improved compared to the 1FGL catalog, we attach caution flags to 162 of the sources to indicate possible confusion with residual imperfections in the diffuse model. The 2FGL catalog contains 1873 sources detected and characterized in the 100 MeV to 100 GeV range of which we consider 127 as being firmly identified and 1171 as being reliably associated with counterparts of known or likely {gamma}-ray-producing source classes.

  11. MASS DETERMINATION STUDIES OF 104 LARGE ASTEROIDS

    SciTech Connect (OSTI)

    Zielenbach, William

    2011-10-15

    The techniques described in an earlier paper were used to determine masses of 104 asteroids by the method of asteroid-asteroid gravitational interaction. For each of the 104 perturbers, 4 large sets of test particles selected by different criteria were used to calculate 4 mass values from a weighted mean of individual results within each set. The sheer number of test particles and observations ameliorates the effects of random observational errors and the type of systematic errors known to have affected specific observatories at specific times. It also reduces the effect of mismodeled attractions by perturbers other than the one being estimated, because the various test particles are affected to different degrees and in different directions. For most of the perturbers that have been analyzed by others, the results of this study agree reasonably well with values published in the past decade, giving credence to the approach. Thirty-eight of the results appear to be the first published masses for the respective asteroids, and 12 are the first determinations based on asteroid-asteroid interactions. Unrealistic and/or negative masses were obtained for some perturbers. Causes for this phenomenon are discussed and various means to obtain reasonable numbers are evaluated.

  12. A large hadron electron collider at CERN

    SciTech Connect (OSTI)

    Abelleira Fernandez, J. L.

    2015-04-06

    This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and eletron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100)fb–1. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC.

  13. Superconducting materials for large scale applications

    SciTech Connect (OSTI)

    Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

    2004-05-06

    Significant improvements in the properties ofsuperconducting materials have occurred recently. These improvements arebeing incorporated into the latest generation of wires, cables, and tapesthat are being used in a broad range of prototype devices. These devicesinclude new, high field accelerator and NMR magnets, magnets for fusionpower experiments, motors, generators, and power transmission lines.These prototype magnets are joining a wide array of existing applicationsthat utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments suchas ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising newmaterials such as MgB2 have been discovered and are being studied inorder to assess their potential for new applications. In this paper, wewill review the key developments that are leading to these newapplications for superconducting materials. In some cases, the key factoris improved understanding or development of materials with significantlyimproved properties. An example of the former is the development of Nb3Snfor use in high field magnets for accelerators. In other cases, thedevelopment is being driven by the application. The aggressive effort todevelop HTS tapes is being driven primarily by the need for materialsthat can operate at temperatures of 50 K and higher. The implications ofthese two drivers for further developments will be discussed. Finally, wewill discuss the areas where further improvements are needed in order fornew applications to be realized.

  14. Sector Profiles of Significant Large CHP Markets, March 2004

    Broader source: Energy.gov [DOE]

    Overview of market assessments of large CHP sector profiles of the chemicals, food, and pharmaceuticals sectors

  15. Predicting Large CO2 Adsorption in Aluminosilicate Zeolites for...

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

    Predicting Large CO2 Adsorption in Aluminosilicate Zeolites for Postcombustion Carbon Dioxide Capture...

  16. Sensitivity technologies for large scale simulation.

    SciTech Connect (OSTI)

    Collis, Samuel Scott; Bartlett, Roscoe Ainsworth; Smith, Thomas Michael; Heinkenschloss, Matthias; Wilcox, Lucas C.; Hill, Judith C.; Ghattas, Omar; Berggren, Martin Olof; Akcelik, Volkan; Ober, Curtis Curry; van Bloemen Waanders, Bart Gustaaf; Keiter, Eric Richard

    2005-01-01

    Sensitivity analysis is critically important to numerous analysis algorithms, including large scale optimization, uncertainty quantification,reduced order modeling, and error estimation. Our research focused on developing tools, algorithms and standard interfaces to facilitate the implementation of sensitivity type analysis into existing code and equally important, the work was focused on ways to increase the visibility of sensitivity analysis. We attempt to accomplish the first objective through the development of hybrid automatic differentiation tools, standard linear algebra interfaces for numerical algorithms, time domain decomposition algorithms and two level Newton methods. We attempt to accomplish the second goal by presenting the results of several case studies in which direct sensitivities and adjoint methods have been effectively applied, in addition to an investigation of h-p adaptivity using adjoint based a posteriori error estimation. A mathematical overview is provided of direct sensitivities and adjoint methods for both steady state and transient simulations. Two case studies are presented to demonstrate the utility of these methods. A direct sensitivity method is implemented to solve a source inversion problem for steady state internal flows subject to convection diffusion. Real time performance is achieved using novel decomposition into offline and online calculations. Adjoint methods are used to reconstruct initial conditions of a contamination event in an external flow. We demonstrate an adjoint based transient solution. In addition, we investigated time domain decomposition algorithms in an attempt to improve the efficiency of transient simulations. Because derivative calculations are at the root of sensitivity calculations, we have developed hybrid automatic differentiation methods and implemented this approach for shape optimization for gas dynamics using the Euler equations. The hybrid automatic differentiation method was applied to a first

  17. Metal Cutting for Large Component Removal

    SciTech Connect (OSTI)

    Hulick, Robert M.

    2008-01-15

    Decommissioning of commercial nuclear power plants presents technological challenges. One major challenge is the removal of large components mainly consisting of the reactor vessel, steam generators and pressurizer. In order to remove and package these large components nozzles must be cut from the reactor vessel to precise tolerances. In some cases steam generators must be segmented for size and weight reduction. One innovative technology that has been used successfully at several commercial nuclear plant decommissioning is diamond wire sawing. Diamond wire sawing is performed by rotating a cable with diamond segments attached using a flywheel approximately 24 inches in diameter driven remotely by a hydraulic pump. Tension is provided using a gear rack drive which also takes up the slack in the wire. The wire is guided through the use of pulleys keeps the wire in a precise location. The diamond wire consists of 1/4 inch aircraft cable with diamond beads strung over the cable separated by springs and brass crimps. Standard wire contains 40 diamond beads per meter and can be made to any length. Cooling the wire and controlling the spread of contamination presents significant challenges. Under normal circumstances the wire is cooled and the cutting kerf cleaned by using water. In some cases of reactor nozzle cuts the use of water is prohibited because it cannot be controlled. This challenge was solved by using liquid Carbon Dioxide as the cooling agent. The liquid CO{sub 2} is passed through a special nozzle which atomizes the liquid into snowflakes which is introduced under pressure to the wire. The snowflakes attach to the wire keeping it cool and to the metal shavings. As the CO{sub 2} and metal shavings are released from the wire due to its fast rotation, the snowflakes evaporate leaving only the fine metal shavings as waste. Secondary waste produced is simply the small volume of fine metal shavings removed from the cut surface. Diamond wire sawing using CO{sub 2

  18. Large Break LOCA Accident Management Strategies for Accidents With Large Containment Leaks

    SciTech Connect (OSTI)

    Sdouz, Gert

    2006-07-01

    The goal of this work is the investigation of the influence of different accident management strategies on the thermal-hydraulics in the containment during a Large Break Loss of Coolant Accident with a large containment leak from the beginning of the accident. The increasing relevance of terrorism suggests a closer look at this kind of severe accidents. Normally the course of severe accidents and their associated phenomena are investigated with the assumption of an intact containment from the beginning of the accident. This intact containment has the ability to retain a large part of the radioactive inventory. In these cases there is only a release via a very small leakage due to the un-tightness of the containment up to cavity bottom melt through. This paper represents the last part of a comprehensive study on the influence of accident management strategies on the source term of VVER-1000 reactors. Basically two different accident sequences were investigated: the 'Station Blackout'- sequence and the 'Large Break LOCA'. In a first step the source term calculations were performed assuming an intact containment from the beginning of the accident and no accident management action. In a further step the influence of different accident management strategies was studied. The last part of the project was a repetition of the calculations with the assumption of a damaged containment from the beginning of the accident. This paper concentrates on the last step in the case of a Large Break LOCA. To be able to compare the results with calculations performed years ago the calculations were performed using the Source Term Code Package (STCP), hydrogen explosions are not considered. In this study four different scenarios have been investigated. The main parameter was the switch on time of the spray systems. One of the results is the influence of different accident management strategies on the source term. In the comparison with the sequence with intact containment it was

  19. Locality and rapidity of the ultra-large elastic deformation...

    Office of Scientific and Technical Information (OSTI)

    Locality and rapidity of the ultra-large elastic deformation of Nb nanowires in a NiTi phase-transforming matrix Title: Locality and rapidity of the ultra-large elastic deformation ...

  20. Development of Large Format Lithium Ion Cells with Higher Energy...

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

    Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500WhL Development of Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500WhL 2012 DOE ...

  1. Non-Large Hadron Collider Physics Program at CERN (Conference...

    Office of Scientific and Technical Information (OSTI)

    Non-Large Hadron Collider Physics Program at CERN Citation Details In-Document Search Title: Non-Large Hadron Collider Physics Program at CERN You are accessing a document from...

  2. A Look at Health Care Buildings - How large are they

    U.S. Energy Information Administration (EIA) Indexed Site

    Large? Return to: A Look at Health Care Buildings How large are they? How many employees are there? Where are they located? How old are they? Who owns and occupies them? Are they...

  3. Large-Volume Resonant Microwave Discharge for Plasma Cleaning...

    Office of Scientific and Technical Information (OSTI)

    Large-Volume Resonant Microwave Discharge for Plasma Cleaning of a CEBAF 5-Cell SRF Cavity Citation Details In-Document Search Title: Large-Volume Resonant Microwave Discharge for...

  4. Large Non-Gaussianity in Axion Inflation (Journal Article) |...

    Office of Scientific and Technical Information (OSTI)

    Large Non-Gaussianity in Axion Inflation Prev Next Title: Large Non-Gaussianity in Axion Inflation Authors: Barnaby, Neil ; Peloso, Marco Publication Date: 2011-05-05 OSTI ...

  5. Locations of Smart Grid Demonstration and Large-Scale Energy...

    Office of Environmental Management (EM)

    Locations of Smart Grid Demonstration and Large-Scale Energy Storage Projects Locations of Smart Grid Demonstration and Large-Scale Energy Storage Projects Map of the United States ...

  6. Fail-Safe Designs for Large Capacity Battery Systems - Energy...

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

    Return to Search Fail-Safe Designs for Large Capacity Battery Systems United States Patent ... Design for Large Capacity Li-Ion Battery Systems Abstract: Fail-safe systems and ...

  7. Stimulated forward Raman scattering in large scale-length laser...

    Office of Scientific and Technical Information (OSTI)

    in large scale-length laser-produced plasmas Citation Details In-Document Search Title: Stimulated forward Raman scattering in large scale-length laser-produced plasmas You ...

  8. Large N (=3) Neutrinos and Random Matrix Theory (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Large N (3) Neutrinos and Random Matrix Theory Citation Details In-Document Search Title: Large N (3) Neutrinos and Random Matrix Theory You are accessing a ...

  9. Plan for support of large-plant (post-CRBR) needs in large-leak sodium-water reaction area

    SciTech Connect (OSTI)

    Whipple, J.C.

    1980-03-01

    Work in the large leak test and analysis area of steam generator development has been carried out at GE-ARSD under 189a SG037 since 1973. The currently planned master schedule for the SG037 program is shown. Principal activities are the large leak testing program being carried out at the Large Leak Test Rig and the analysis methods development. The plan for supporting the large plant (post-CRBR) needs in the large leak sodium-water reaction area is outlined. Most of the needs will be answered in the current SG037 large leak program. (DLC)

  10. SimFS: A Large Scale Parallel File System Simulator

    Energy Science and Technology Software Center (OSTI)

    2011-08-30

    The software provides both framework and tools to simulate a large-scale parallel file system such as Lustre.

  11. DLFM library tools for large scale dynamic applications

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

    DLFM library tools for large scale dynamic applications DLFM library tools for large scale dynamic applications Large scale Python and other dynamic applications may spend huge time at startup. The DLFM library, developed by Mike Davis at Cray, Inc., is a set of functions that can be incorporated into a dynamically-linked application to provide improved performance during the loading of dynamic libraries when running the application at large scale on Edison. To access this library, do module

  12. Nuclear EMP simulation for large-scale urban environments. FDTD for electrically large problems.

    SciTech Connect (OSTI)

    Smith, William S.; Bull, Jeffrey S.; Wilcox, Trevor; Bos, Randall J.; Shao, Xuan-Min; Goorley, John T.; Costigan, Keeley R.

    2012-08-13

    In case of a terrorist nuclear attack in a metropolitan area, EMP measurement could provide: (1) a prompt confirmation of the nature of the explosion (chemical or nuclear) for emergency response; and (2) and characterization parameters of the device (reaction history, yield) for technical forensics. However, urban environment could affect the fidelity of the prompt EMP measurement (as well as all other types of prompt measurement): (1) Nuclear EMP wavefront would no longer be coherent, due to incoherent production, attenuation, and propagation of gamma and electrons; and (2) EMP propagation from source region outward would undergo complicated transmission, reflection, and diffraction processes. EMP simulation for electrically-large urban environment: (1) Coupled MCNP/FDTD (Finite-difference time domain Maxwell solver) approach; and (2) FDTD tends to be limited to problems that are not 'too' large compared to the wavelengths of interest because of numerical dispersion and anisotropy. We use a higher-order low-dispersion, isotropic FDTD algorithm for EMP propagation.

  13. Performance of large electron energy filter in large volume plasma device

    SciTech Connect (OSTI)

    Singh, S. K.; Srivastava, P. K.; Awasthi, L. M.; Mattoo, S. K.; Sanyasi, A. K.; Kaw, P. K. [Institute for Plasma Research, Gandhinagar 382 428, Gujarat (India)] [Institute for Plasma Research, Gandhinagar 382 428, Gujarat (India); Singh, R. [Institute for Plasma Research, Gandhinagar 382 428, Gujarat (India) [Institute for Plasma Research, Gandhinagar 382 428, Gujarat (India); WCI Center for Fusion Theory, National Fusion Research Institute Gwahangno 113, Yu-seong-gu, Daejeon, 305-333 (Korea, Republic of)

    2014-03-15

    This paper describes an in-house designed large Electron Energy Filter (EEF) utilized in the Large Volume Plasma Device (LVPD) [S. K. Mattoo, V. P. Anita, L. M. Awasthi, and G. Ravi, Rev. Sci. Instrum. 72, 3864 (2001)] to secure objectives of (a) removing the presence of remnant primary ionizing energetic electrons and the non-thermal electrons, (b) introducing a radial gradient in plasma electron temperature without greatly affecting the radial profile of plasma density, and (c) providing a control on the scale length of gradient in electron temperature. A set of 19 independent coils of EEF make a variable aspect ratio, rectangular solenoid producing a magnetic field (B{sub x}) of 100?G along its axis and transverse to the ambient axial field (B{sub z} ? 6.2?G) of LVPD, when all its coils are used. Outside the EEF, magnetic field reduces rapidly to 1?G at a distance of 20 cm from the center of the solenoid on either side of target and source plasma. The EEF divides LVPD plasma into three distinct regions of source, EEF and target plasma. We report that the target plasma (n{sub e} ? 2 10{sup 11}?cm{sup ?3} and T{sub e} ? 2?eV) has no detectable energetic electrons and the radial gradients in its electron temperature can be established with scale length between 50?and?600 cm by controlling EEF magnetic field. Our observations reveal that the role of the EEF magnetic field is manifested by the energy dependence of transverse electron transport and enhanced transport caused by the plasma turbulence in the EEF plasma.

  14. Large-Scale Federal Renewable Energy Projects | Department of Energy

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

    Large-Scale Federal Renewable Energy Projects Large-Scale Federal Renewable Energy Projects Renewable energy projects larger than 10 megawatts (MW), also known as utility-scale projects, are complex and typically require private-sector financing. The Federal Energy Management Program (FEMP) developed a guide to help federal agencies, and the developers and financiers that work with them, to successfully install these projects at federal facilities. FEMP's Large-Scale Renewable Energy Guide,

  15. Finding Large Aperture Fractures in Geothermal Resource Areas Using A

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

    Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis | Department of Energy Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Fining Large Aperture Fractures in Geothermal Resource Areas Using A

  16. Energy Department Applauds Nation's First Large-Scale Industrial Carbon

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

    Capture and Storage Facility | Department of Energy Nation's First Large-Scale Industrial Carbon Capture and Storage Facility Energy Department Applauds Nation's First Large-Scale Industrial Carbon Capture and Storage Facility August 24, 2011 - 6:23pm Addthis Washington, D.C. - The U.S. Department of Energy issued the following statement in support of today's groundbreaking for construction of the nation's first large-scale industrial carbon capture and storage (ICCS) facility in Decatur,

  17. Large Scale Computing and Storage Requirements for Advanced Scientific

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

    Computing Research: Target 2014 Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research: Target 2014 ASCRFrontcover.png Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research An ASCR / NERSC Review January 5-6, 2011 Final Report Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research, Report of the Joint ASCR / NERSC Workshop conducted January 5-6, 2011 Goals This workshop is being

  18. Large Scale Computing and Storage Requirements for Basic Energy Sciences:

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

    Target 2014 Large Scale Computing and Storage Requirements for Basic Energy Sciences: Target 2014 BESFrontcover.png Final Report Large Scale Computing and Storage Requirements for Basic Energy Sciences, Report of the Joint BES/ ASCR / NERSC Workshop conducted February 9-10, 2010 Workshop Agenda The agenda for this workshop is presented here: including presentation times and speaker information. Read More » Workshop Presentations Large Scale Computing and Storage Requirements for Basic

  19. Large Scale Computing and Storage Requirements for High Energy Physics

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

    Large Scale Computing and Storage Requirements for High Energy Physics HEPFrontcover.png Large Scale Computing and Storage Requirements for High Energy Physics An HEP / ASCR / NERSC Workshop November 12-13, 2009 Report Large Scale Computing and Storage Requirements for High Energy Physics, Report of the Joint HEP / ASCR / NERSC Workshop conducted Nov. 12-13, 2009 https://www.nersc.gov/assets/HPC-Requirements-for-Science/HEPFrontcover.png Goals This workshop was organized by the Department of

  20. Addressing Security and Reliability Concerns of Large Power Transformers |

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

    Department of Energy Services » Addressing Security and Reliability Concerns of Large Power Transformers Addressing Security and Reliability Concerns of Large Power Transformers Large power transformers (LPTs) are critical to the nation's power grid, with more than 90 percent of consumed power passing through high-voltage transformers at some point. LPTs, however, face a number of challenges that make them one of the most vulnerable components on the grid. They are expensive, difficult to

  1. Large-Scale Industrial Carbon Capture, Storage Plant Begins Construction |

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

    Department of Energy Large-Scale Industrial Carbon Capture, Storage Plant Begins Construction Large-Scale Industrial Carbon Capture, Storage Plant Begins Construction August 24, 2011 - 1:00pm Addthis Washington, DC - Construction activities have begun at an Illinois ethanol plant that will demonstrate carbon capture and storage. The project, sponsored by the U.S. Department of Energy's Office of Fossil Energy, is the first large-scale integrated carbon capture and storage (CCS) demonstration

  2. Building America Webinar: Opportunities in Large Data Collection and

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

    Analysis | Department of Energy Opportunities in Large Data Collection and Analysis Building America Webinar: Opportunities in Large Data Collection and Analysis The webinar, presented on April 16, 2014, focused on specific Building America projects that are looking to gather and analyze large bodies of data on new and existing homes, and discussed opportunities for industry to collaborate with researchers to gather and analyze valuable data. View the presentations: Introduction and Building

  3. Ultrasound Measurements of Cerium under High Pressure in a Large...

    Office of Scientific and Technical Information (OSTI)

    Ultrasound Measurements of Cerium under High Pressure in a Large Volume Press Combined ... Citation Details In-Document Search Title: Ultrasound Measurements of Cerium under High ...

  4. Strategies to Finance Large-Scale Deployment of Renewable Energy...

    Open Energy Info (EERE)

    to Finance Large-Scale Deployment of Renewable Energy Projects: An Economic Development and Infrastructure Approach Jump to: navigation, search Tool Summary LAUNCH TOOL Name:...

  5. Secondary electron yield of emissive materials for large-area...

    Office of Scientific and Technical Information (OSTI)

    Conference: Secondary electron yield of emissive materials for large-area micro-channel plate detectors: surface composition and film thickness dependencies Citation Details ...

  6. South Dakota's At-large congressional district: Energy Resources...

    Open Energy Info (EERE)

    At-large congressional district Black Hills Corporation Broin Associates Broin Enterprises Capitaline Advisors LLC Dakota Ethanol Deadwood Biofuels LLC Kramer Energy Group...

  7. Texas Large Construction Site Notice for Secondary Operators...

    Open Energy Info (EERE)

    navigation, search OpenEI Reference LibraryAdd to library Reference: Texas Large Construction Site Notice for Secondary Operators Published Texas Commission on Environmental...

  8. Texas Large Construction Site Notice for Primary Operators |...

    Open Energy Info (EERE)

    navigation, search OpenEI Reference LibraryAdd to library Reference: Texas Large Construction Site Notice for Primary Operators Published Texas Commission on Environmental...

  9. Understanding large scale HPC systems through scalable monitoring...

    Office of Scientific and Technical Information (OSTI)

    HPC systems through scalable monitoring and analysis. Citation Details In-Document Search Title: Understanding large scale HPC systems through scalable monitoring and analysis. ...

  10. New route toward integrating large nickel nanocrystals onto mesoporous...

    Office of Scientific and Technical Information (OSTI)

    New route toward integrating large nickel nanocrystals onto mesoporous carbons This content will become publicly available on December 30, 2016 Title: New route toward integrating ...

  11. QER- Comment of Large Public Power Council 1

    Broader source: Energy.gov [DOE]

    Attached are the Comments of the Large Public Power Council on the QER. Please feel to contact me if you have any questions.

  12. FEMP Helps Federal Facilities Develop Large-Scale Renewable Energy...

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

    jobs, and advancing national goals for energy security. The guide describes the fundamentals of deploying financially attractive, large-scale renewable energy projects and...

  13. DOE Receives Responses on the Implementation of Large-Capacity...

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

    establishing alternative test procedures for existing large-capacity residential clothes washer models and units. We received responses from several parties, which can be...

  14. Optimizing Cluster Heads for Energy Efficiency in Large-Scale...

    Office of Scientific and Technical Information (OSTI)

    Optimizing Cluster Heads for Energy Efficiency in Large-Scale Heterogeneous Wireless Sensor Networks Gu, Yi; Wu, Qishi; Rao, Nageswara S. V. Hindawi Publishing Corporation None...

  15. Energy Department Applauds Nation's First Large-Scale Industrial...

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

    ... News Media Contact: 202-586-4940 Addthis Related Articles Large-Scale Industrial Carbon ... designed National Sequestration Education Center, located at Richland Community ...

  16. Dynamical transitions in large systems of mean field-coupled...

    Office of Scientific and Technical Information (OSTI)

    chaos and cluster states Citation Details In-Document Search Title: Dynamical transitions in large systems of mean field-coupled Landau-Stuart oscillators: Extensive chaos and ...

  17. Modal Dynamics and Stability of Large Multi-megawatt Deepwater...

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

    A vertical-axis wind turbine (VAWT) rotor configuration offers a potential transformative ... The effect of the large rotating structure on the rigid body modes of the turbineplatform ...

  18. Large Fleets Lead in Petroleum Reduction (Fact Sheet)

    SciTech Connect (OSTI)

    Proc, H.

    2011-03-01

    Fact sheet describes Clean Cities' National Petroleum Reduction Partnership, an initiative through which large private fleets can receive support from Clean Cities to reduce petroleum consumption.

  19. Optimizing Cluster Heads for Energy Efficiency in Large-Scale...

    Office of Scientific and Technical Information (OSTI)

    clustering is generally considered as an efficient and scalable way to facilitate the management and operation of such large-scale networks and minimize the total energy...

  20. A Model for Turbulent Combustion Simulation of Large Scale Hydrogen...

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

    A Model for Turbulent Combustion Simulation of Large Scale Hydrogen Explosions Event Sponsor: Argonne Leadership Computing Facility Seminar Start Date: Oct 6 2015 - 10:00am...

  1. Number of Large Energy User Manufacturing Facilities by Sector...

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

    Number of Large Energy User Manufacturing Facilities by Sector and State (with Industrial Energy Consumption by State and Manufacturing Energy Consumption by Sector) State...

  2. Harvey Wasserman! Large Scale Computing and Storage Requirements...

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

    Large Scale Computing and Storage Requirements for High Energy Physics Research: Target 2017 ...www.nersc.govsciencerequirementsHEP * Mid---morning a

  3. Large Scale Production Computing and Storage Requirements for...

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

    Large Scale Production Computing and Storage Requirements for High Energy Physics: Target 2017 ... Energy's Office of High Energy Physics (HEP), Office of Advanced Scientific ...

  4. Predicting Large CO2 Adsorption in Aluminosilicate Zeolites for...

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

    Large CO2 Adsorption in Aluminosilicate Zeolites for Postcombustion Carbon Dioxide Capture Previous Next List Jihan Kim, Li-Chiang Lin, Joseph A. Swisher, Maciej Haranczyk, and...

  5. LARGE INDUSTRIAL FACILITIES BY STATE | Department of Energy

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

    Number of Large Energy User Manufacturing Facilities by Sector and State (with Industrial Energy Consumption by State and Manufacturing Energy Consumption by Sector) More Documents ...

  6. Finding Large Aperture Fractures in Geothermal Resource Areas...

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

    ...-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface Seismic ...

  7. Effects of Large Energetic Vortices on Axial-Flow Hydrokinetic...

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

    around large or full scale MHK machines in the field. In this study three synchronized acoustic Doppler velocimeters ... The SAFL Main Channel Data Acquisition (DAQ) Carriage, ...

  8. Panel 1, Towards Sustainable Energy Systems: The Role of Large...

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

    Towards sustainable energy systems - The role of large scale hydrogen storage in Germany May 14th, 2014 | ... Three reasons why it is inevitable to change the energy system ...

  9. Overcoming the Barrier to Achieving Large-Scale Production -...

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

    Semprius Confidential 1 Overcoming the Barriers to Achieving Large-Scale Production - A ... August 31, 2011 Semprius Confidential 2 Semprius Overview Background Company: * Leading ...

  10. Large Campus Innovative Change Initiative | Department of Energy

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

    laws and requirements, maintain their missions, and manage large facility portfolios. ... focus on multiple, often conflicting, missions Campus energy and water metering ...

  11. Building America Webinar: Opportunities in Large Data Collection...

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

    Analysis Building America Webinar: Opportunities in Large Data Collection and Analysis This introductory presentation for the webinar held on April 16, 2014, gives an overview of ...

  12. Building America Webinar: Opportunities in Large Data Collection...

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

    Analysis-Presentation 3 Building America Webinar: Opportunities in Large Data Collection and Analysis-Presentation 3 This is the third presentation, Indoor Temperature and ...

  13. Search for Large Extra Dimensions Based on Observations of Neutron...

    Office of Scientific and Technical Information (OSTI)

    Large extra dimensions (LED) have been proposed to account for the apparent weakness of gravitation. These theories also indicate that the postulated massive Kaluza-Klein (KK) ...

  14. Fabrication and current optical performance of a large diamond...

    Office of Scientific and Technical Information (OSTI)

    Fabrication and current optical performance of a large diamond-machined ZnSe immersion grating Citation Details In-Document Search Title: Fabrication and current optical ...

  15. Large-Scale Hydropower Basics | Department of Energy

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

    Renewable Energy » Hydropower » Large-Scale Hydropower Basics Large-Scale Hydropower Basics August 14, 2013 - 3:11pm Addthis Large-scale hydropower plants are generally developed to produce electricity for government or electric utility projects. These plants are more than 30 megawatts (MW) in size, and there is more than 80,000 MW of installed generation capacity in the United States today. Most large-scale hydropower projects use a dam and a reservoir to retain water from a river. When the

  16. Development of Integrated Die Casting Process for Large Thin...

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

    Enabling Production of Lightweight Magnesium Parts for Near-Term Automotive Applications. ... cost and most productive casting process for producing large and complex automotive parts. ...

  17. Finding Large Aperture Fractures in Geothermal Resource Areas...

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

    DOE Geothermal Peer Review 2010 - Presentation. Project summary: Drilling into large aperture open fractures (LAFs) typically yield production wells with high productivity and ...

  18. Large-Eddy Simulation for Green Energy and Propulsion Systems...

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

    Large-Eddy Simulation for Green Energy and Propulsion Systems PI Name: Umesh Paliath PI Email: paliath@ge.com Institution: General Electric Allocation Program: INCITE Allocation ...

  19. Explosive performance measurements on large, multiple-hole arrays and large masses of conventional explosive

    SciTech Connect (OSTI)

    McKown, T.O.; Eilers, D.D.; Williams, P.E.

    1994-11-01

    The COntinuous Reflectometry for Radius vs. Time EXperiment (CORRTEX) system was developed by the Los Alamos National Laboratory for determining the energy released in a nuclear explosion by measuring the position of its shock front as a function of time. The CORRTEX system, fielding techniques, and the methods and software for data reduction and analysis were developed over a 15 year period with hundreds of measurements made on nuclear tests and high explosive experiments. CORRTEX is a compact, portable, fast-sampling, microprocessor-controlled system, based on time domain reflectometry, requiring only a 24 volt power source and a sensing element. Only the sensing element (a length of 50 ohm coaxial cable) is expended during the detonation. In 1979, the CORRTEX system was shown to be ideally suited for chemical explosive performance measurements. Its utility for diagnosing chemical explosives was further demonstrated with successful measurements on large multiple-hole chemical shots in rock quarries and strip mines. Accurate timing of the detonation of sequenced or ripple fired arrays, as well as data characterizing the initiation, explosive performance and detonation anomalies are obtained. This information can serve as the basis for empirical or modeled improvements to blasting operations. A summary of the special CORRTEX features and well developed analysis techniques together with the experiment designs, data, and conclusions regarding the measurements and explosive performance from several array detonations and the Chemical Kiloton Experiment, 2.9 million pounds of an ammonium nitrate-fuel oil (ANFO) and emulsion blend conducted on the Nevada Test Site in 1993, are presented.

  20. Lessons from Large-Scale Renewable Energy Integration Studies: Preprint

    SciTech Connect (OSTI)

    Bird, L.; Milligan, M.

    2012-06-01

    In general, large-scale integration studies in Europe and the United States find that high penetrations of renewable generation are technically feasible with operational changes and increased access to transmission. This paper describes other key findings such as the need for fast markets, large balancing areas, system flexibility, and the use of advanced forecasting.

  1. Final Scientific/Technical Report: Electronics for Large Superconducting Tunnel Junction Detector Arrays for Synchrotron Soft X-ray Research

    SciTech Connect (OSTI)

    Warburton, William K

    2009-03-06

    Superconducting tunnel junction (STJ) detectors offer a an approach to detecting soft x-rays with energy resolutions 4-5 times better and at rates 10 faster than traditions semiconductor detectors. To make such detectors feasible, however, then need to be deployed in large arrays of order 1000 detectors, which in turn implies that their processing electronics must be compact, fully computer controlled, and low cost per channel while still delivering ultra-low noise performance so as to not degrade the STJ's performance. We report on our progress in designing a compact, low cost preamplifier intended for this application. In particular, we were able to produce a prototype preamplifier of 2 sq-cm area and a parts cost of less than $30 that matched the energy resolution of the best conventional system to date and demonstrated its ability to acquire an STJ I-V curve under computer control, the critical step for determining and setting the detectors' operating points under software control.

  2. Key management for large scale end-to-end encryption

    SciTech Connect (OSTI)

    Witzke, E.L.

    1994-07-01

    Symmetric end-to-end encryption requires separate keys for each pair of communicating confidants. This is a problem of Order N{sup 2}. Other factors, such as multiple sessions per pair of confidants and multiple encryption points in the ISO Reference Model complicate key management by linear factors. Public-key encryption can reduce the number of keys managed to a linear problem which is good for scaleability of key management, but comes with complicating issues and performance penalties. Authenticity is the primary ingredient of key management. If each potential pair of communicating confidants can authenticate data from each other, then any number of public encryption keys of any type can be communicated with requisite integrity. These public encryption keys can be used with the corresponding private keys to exchange symmetric cryptovariables for high data rate privacy protection. The Digital Signature Standard (DSS), which has been adopted by the United States Government, has both public and private components, similar to a public-key cryptosystem. The Digital Signature Algorithm of the DSS is intended for authenticity but not for secrecy. In this paper, the authors will show how the use of the Digital Signature Algorithm combined with both symmetric and asymmetric (public-key) encryption techniques can provide a practical solution to key management scaleability problems, by reducing the key management complexity to a problem of order N, without sacrificing the encryption speed necessary to operate in high performance networks.

  3. Aging assessment of large electric motors in nuclear power plants

    SciTech Connect (OSTI)

    Villaran, M.; Subudhi, M.

    1996-03-01

    Large electric motors serve as the prime movers to drive high capacity pumps, fans, compressors, and generators in a variety of nuclear plant systems. This study examined the stressors that cause degradation and aging in large electric motors operating in various plant locations and environments. The operating history of these machines in nuclear plant service was studied by review and analysis of failure reports in the NPRDS and LER databases. This was supplemented by a review of motor designs, and their nuclear and balance of plant applications, in order to characterize the failure mechanisms that cause degradation, aging, and failure in large electric motors. A generic failure modes and effects analysis for large squirrel cage induction motors was performed to identify the degradation and aging mechanisms affecting various components of these large motors, the failure modes that result, and their effects upon the function of the motor. The effects of large motor failures upon the systems in which they are operating, and on the plant as a whole, were analyzed from failure reports in the databases. The effectiveness of the industry`s large motor maintenance programs was assessed based upon the failure reports in the databases and reviews of plant maintenance procedures and programs.

  4. Fail Safe Design for Large Capacity Lithium-ion Batteries

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

    Fail Safe Design for Large Capacity Lithium-ion Batteries NREL Commercialization & Tech Transfer Webinar March 27, 2011 Gi-Heon Kim gi-heon.kim@nrel.gov John Ireland, Kyu-Jin Lee, Ahmad Pesaran Kandler Smith kandler.smith@nrel.gov Source: A123 Source: GM NATIONAL RENEWABLE ENERGY LABORATORY Challenges for Large LIB Systems 2 * Li-ion batteries are flammable, require expensive manufacturing to reduce defects * Small-cell protection devices do not work for large systems * Difficult to detect

  5. Manufacturing process to reduce large grain growth in zirconium alloys

    DOE Patents [OSTI]

    Rosecrans, P.M.

    1984-08-01

    It is an object of the present invention to provide a procedure for desensitizing zirconium-based alloys to large grain growth (LGG) during thermal treatment above the recrystallization temperature of the alloy. It is a further object of the present invention to provide a method for treating zirconium-based alloys which have been cold-worked in the range of 2 to 8% strain to reduce large grain growth. It is another object of the present invention to provide a method for fabricating a zirconium alloy clad nuclear fuel element wherein the zirconium clad is resistant to large grain growth.

  6. Large scale condensed matter and fluid dynamics simulations | Argonne

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

    Leadership Computing Facility , (a)Snapshots of the vorticity field of a UPO located in weakly turbulent flow with Re=371 and period equal to 26864 LB time steps. The quantity shown is the magnitude of vorticity above a given cut-off level. Red corresponds to large negative vorticity (clockwise rotation), and blue to large positive vorticity (counter-clockwise rotation). (b)Initial stucture of the large LDH-nucleic acid models, (a) System, at the start of the simulation. For clarity, water

  7. Sol-gel-derived Epitaxial Nanocomposite Thin Films with Large...

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

    Sol-gel-derived Epitaxial Nanocomposite Thin Films with Large Sharp Magnetoelectric Effect Home Author: B. Liu, T. Sun, J. He, V. P. Dravid Year: 2010 Abstract: Nanostructures of...

  8. Evaluating Benefits of Idling Restrictions in a Large Northern City

    Broader source: Energy.gov [DOE]

    While an anti-idling law in a large northern city has brought about the deployment of anti-idling technologies in city vehicles, it has not had the same effect on some classes of private vehicles.

  9. ARM - Evaluation Product - Vertical Air Motion during Large-Scale...

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

    ProductsVertical Air Motion during Large-Scale Stratiform Rain ARM Data Discovery Browse ... Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Vertical Air ...

  10. Plasma deposited diamond-like carbon films for large neutralarrays

    SciTech Connect (OSTI)

    Brown, I.G.; Blakely, E.A.; Bjornstad, K.A.; Galvin, J.E.; Monteiro, O.R.; Sangyuenyongpipat, S.

    2004-07-15

    To understand how large systems of neurons communicate, we need to develop methods for growing patterned networks of large numbers of neurons. We have found that diamond-like carbon thin films formed by energetic deposition from a filtered vacuum arc carbon plasma can serve as ''neuron friendly'' substrates for the growth of large neural arrays. Lithographic masks can be used to form patterns of diamond-like carbon, and regions of selective neuronal attachment can form patterned neural arrays. In the work described here, we used glass microscope slides as substrates on which diamond-like carbon was deposited. PC-12 rat neurons were then cultured on the treated substrates and cell growth monitored. Neuron growth showed excellent contrast, with prolific growth on the treated surfaces and very low growth on the untreated surfaces. Here we describe the vacuum arc plasma deposition technique employed, and summarize results demonstrating that the approach can be used to form large patterns of neurons.

  11. Geranyl diphosphate synthase large subunit, and methods of use

    DOE Patents [OSTI]

    Croteau, Rodney B.; Burke, Charles C.; Wildung, Mark R.

    2001-10-16

    A cDNA encoding geranyl diphosphate synthase large subunit from peppermint has been isolated and sequenced, and the corresponding amino acid sequence has been determined. Replicable recombinant cloning vehicles are provided which code for geranyl diphosphate synthase large subunit). In another aspect, modified host cells are provided that have been transformed, transfected, infected and/or injected with a recombinant cloning vehicle and/or DNA sequence encoding geranyl diphosphate synthase large subunit. In yet another aspect, the present invention provides isolated, recombinant geranyl diphosphate synthase protein comprising an isolated, recombinant geranyl diphosphate synthase large subunit protein and an isolated, recombinant geranyl diphosphate synthase small subunit protein. Thus, systems and methods are provided for the recombinant expression of geranyl diphosphate synthase.

  12. Towards a Large-Scale Recording System: Demonstration of Polymer...

    Office of Scientific and Technical Information (OSTI)

    of Polymer-Based Penetrating Array for Chronic Neural Recording Citation Details In-Document Search Title: Towards a Large-Scale Recording System: Demonstration of Polymer-Based ...

  13. Large-N volume independence in conformal and confining gauge...

    Office of Scientific and Technical Information (OSTI)

    In particular, this implies that a large N gauge theory which, on Rsup d, flows to an IR fixed point, retains the infinite correlation length and other scale invariant...

  14. Limits on Large Extra Dimensions Based on Observations of Neutron...

    Office of Scientific and Technical Information (OSTI)

    theory of Large Extra Dimensions (LED) proposed by Arkani-Hamed, Dimopoulos, and Dvali. ... faint neutron stars (NS). To set limits on LED we use the model of Hannestad and Raffelt ...

  15. Exploiting large non-isomorphous differences for phase determination...

    Office of Scientific and Technical Information (OSTI)

    of a G-segment invertase-DNA complex Citation Details In-Document Search Title: Exploiting large non-isomorphous differences for phase determination of a G-segment ...

  16. Fermi Large Area Telescope Observations of the Supernova Remnant...

    Office of Scientific and Technical Information (OSTI)

    Fermi Large Area Telescope Observations of the Supernova Remnant G8.7-0.1 Citation Details ... Language: English Subject: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 72 PHYSICS ...

  17. New Hampshire Electric Co-Op - Large Business Energy Solutions...

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

    Speed Drives: 1,050 - 4,400 Custom: lesser of 35% of the total installed cost or buy down to 1 year pay Summary New Hampshire Electric Co-Op offers incentives for its large...

  18. Fermilab Muon Ring Arrives to a Large Crowd of Fans

    SciTech Connect (OSTI)

    2013-08-15

    A very large group of people gathered to watch the muon g-2 ring on its last leg of the big move from Brookhaven National Laboratory in Long Island, NY to Fermilab in Batavia, IL.

  19. Large-Scale First-Principles Molecular Dynamics Simulations on...

    Office of Scientific and Technical Information (OSTI)

    for large-scale parallel platforms such as BlueGeneL. Strong scaling tests for a Materials Science application show an 86% scaling efficiency between 1024 and 32,768 CPUs. ...

  20. SCIENCE ON SATURDAY- "The Large Hadron Collider: big science...

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

    January 5, 2013, 9:30am Science On Saturday MBG Auditorium SCIENCE ON SATURDAY- "The Large Hadron Collider: big science for big questions" Professor James Olsen Department of ...

  1. COLLOQUIUM: Liquid Metal Batteries for Large-scale Energy Storage...

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

    June 22, 2016, 4:15pm to 5:30pm Colloquia MBG Auditorium, PPPL (284 cap.) COLLOQUIUM: Liquid Metal Batteries for Large-scale Energy Storage Dr. Hojong Kim Pennsylvania State ...

  2. FERC Order No. 2003 Appendix 6 - Large Generator Interconnection...

    Open Energy Info (EERE)

    FERC Order No. 2003 Appendix 6 - Large Generator Interconnection Agreement Jump to: navigation, search OpenEI Reference LibraryAdd to library Form: FERC Order No. 2003 Appendix 6 -...

  3. June 30, 2008: US portion of Large Hadron Collider completed

    Broader source: Energy.gov [DOE]

    June 30, 2008The Department and the National Science Foundation announce that the U.S. contribution to the Large Hadron Collider (LHC) has been completed on budget and ahead of schedule. The LHC,...

  4. Lab Ahead of Schedule Processing Waste in Large Boxes

    Broader source: Energy.gov [DOE]

    LOS ALAMOS, N.M. – The TRU Waste Program at Los Alamos National Laboratory is currently two months ahead of schedule processing and repackaging waste stored in large fiberglass-reinforced boxes (FRPs).

  5. Finding Large Aperture Fractures in Geothermal Resource Areas...

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

    Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface ...

  6. Assessing Galaxy Limiting Magnitudes in Large Optical Surveys...

    Office of Scientific and Technical Information (OSTI)

    Large Optical Surveys Authors: Rykoff, E.S. ; KIPAC, Menlo Park SLAC ; Rozo, E. ; Arizona U. ; Keisler, R. ; KIPAC, Menlo Park Publication Date: 2015-09-17 OSTI Identifier:...

  7. How Three Retail Buyers Source Large-Scale Solar Electricity

    Broader source: Energy.gov [DOE]

    Large-scale, non-utility solar power purchase agreements (PPAs) are still a rarity despite the growing popularity of PPAs across the country. In this webinar, participants will learn more about how...

  8. Glendale Water and Power- Large Business Energy Efficiency Program

    Broader source: Energy.gov [DOE]

    Glendale Water and Power (GWP) offers a rebate to its medium and large business customers with electric bills of more than $3000 per month (electric usage of 250,000 kWh annually ~ $36,000 per year...

  9. Economic and Performance Benefits Resulting From the Use of Large...

    Open Energy Info (EERE)

    was implementedat the Neal Hot Springs geothermal power plant in Vale,Oregon. Large cooling tower fans were used in an induced draftarrangement (fans above the heat exchanger). The...

  10. Property:Building/SPElectrtyUsePercLargeKitchens | Open Energy...

    Open Energy Info (EERE)

    yUsePercLargeKitchens" Showing 25 pages using this property. (previous 25) (next 25) S Sweden Building 05K0001 + 1.06788610412 + Sweden Building 05K0002 + 0.0 + Sweden Building...

  11. Development of Large Area Gas Electron Multiplier Detector and...

    Office of Scientific and Technical Information (OSTI)

    While the important next step was the development of large area (1m x 1m) GEM planes, we also have looked into opportunities of applying this technology to precision tracking ...

  12. Self-consistency tests of large-scale dynamics parameterizations...

    Office of Scientific and Technical Information (OSTI)

    In self-consistency tests based on radiative-convective equilibrium (RCE; i.e., no large-scale convergence), we find that simulations either weakly coupled or strongly coupled to ...

  13. Evaluating Benefits of Idling Restrictions in a Large Northern...

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

    While an anti-idling law in a large northern city has brought about the deployment of anti-idling technologies in city vehicles, it has not had the same effect on some classes of ...

  14. Cosmological Simulations for Large-Scale Sky Surveys | Argonne...

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

    The focus of cosmology today is on its two mysterious pillars, dark matter and dark energy. Large-scale sky surveys are the current drivers of precision cosmology and have been ...

  15. Cosmological Simulations for Large-Scale Sky Surveys | Argonne...

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

    The focus of cosmology today revolves around two mysterious pillars, dark matter and dark energy. Large-scale sky surveys are the current drivers of precision cosmology and have ...

  16. Vacuum gaps with small tunnel currents at large electric field...

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

    small tunnel currents at large electric field and its potential applications for energy storage, charge storage and power supplies. Friday, May 27, 2011 - 4:00pm SSRL Conference...

  17. Revised Environmental Assessment Large-Scale, Open-Air Explosive

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

    Environmental Assessment Large-Scale, Open-Air Explosive Detonation, DIVINE STRAKE, at the Nevada Test Site May 2006 Prepared by Department of Energy National Nuclear Security Administration Nevada Site Office Environmental Assessment May 2006 Large-Scale, Open-Air Explosive Detonation, DIVINE STRAKE, at the Nevada Test Site TABLE OF CONTENTS 1.0 PURPOSE AND NEED FOR ACTION.....................................................1-1 1.1 Introduction and

  18. Breakthrough Large-Scale Industrial Project Begins Carbon Capture and

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

    Utilization | Department of Energy Breakthrough Large-Scale Industrial Project Begins Carbon Capture and Utilization Breakthrough Large-Scale Industrial Project Begins Carbon Capture and Utilization January 25, 2013 - 12:00pm Addthis Washington, DC - A breakthrough carbon capture, utilization, and storage (CCUS) project in Texas has begun capturing carbon dioxide (CO2) and piping it to an oilfield for use in enhanced oil recovery (EOR). Read the project factsheet The project at Air Products

  19. Fail-safe designs for large capacity battery systems

    DOE Patents [OSTI]

    Kim, Gi-Heon; Smith, Kandler; Ireland, John; Pesaran, Ahmad A.; Neubauer, Jeremy

    2016-05-17

    Fail-safe systems and design methodologies for large capacity battery systems are disclosed. The disclosed systems and methodologies serve to locate a faulty cell in a large capacity battery, such as a cell having an internal short circuit, determine whether the fault is evolving, and electrically isolate the faulty cell from the rest of the battery, preventing further electrical energy from feeding into the fault.

  20. The Cielo Petascale Capability Supercomputer: Providing Large-Scale

    Office of Scientific and Technical Information (OSTI)

    Computing for Stockpile Stewardship (Conference) | SciTech Connect Conference: The Cielo Petascale Capability Supercomputer: Providing Large-Scale Computing for Stockpile Stewardship Citation Details In-Document Search Title: The Cielo Petascale Capability Supercomputer: Providing Large-Scale Computing for Stockpile Stewardship Authors: Vigil, Benny Manuel [1] ; Doerfler, Douglas W. [1] + Show Author Affiliations Los Alamos National Laboratory Publication Date: 2013-03-11 OSTI Identifier:

  1. UNIVERSITY OF CALIFORNIA The Future of Large Scale Visual Data

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

    CALIFORNIA The Future of Large Scale Visual Data Analysis Joint Facilities User Forum on Data Intensive Computing Oakland, CA E. Wes Bethel Lawrence Berkeley National Laboratory 16 June 2014 16 June 2014 The World that Was: Computational Architectures * Machine architectures - Single CPU, single core - Vector, then single-core MPPs - "Large" SMP platforms - Relatively well balanced: memory, FLOPS,I/O 16 June 2014 The World that Was: Software Architecture * Data Analysis and

  2. Energy Department Accepting Small Business Grant Applications for Large

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

    Wind Turbines | Department of Energy Accepting Small Business Grant Applications for Large Wind Turbines Energy Department Accepting Small Business Grant Applications for Large Wind Turbines November 26, 2014 - 2:55pm Addthis The Energy Department began accepting applications on November 24 for its FY 2015 Phase 1 grant topics, including a Wind Program topic, under the Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs. SBIR/STTR grants are

  3. Online Monitoring Technical Basis and Analysis Framework for Large Power

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

    Transformers; Interim Report for FY 2012 | Department of Energy for Large Power Transformers; Interim Report for FY 2012 Online Monitoring Technical Basis and Analysis Framework for Large Power Transformers; Interim Report for FY 2012 The Light Water Reactor Sustainability Program is a research, development, and deployment program sponsored by the U.S. Department of Energy Office of Nuclear Energy. The program is operated in collaboration with the Electric Power Research Institute's (EPRI's)

  4. Large Eddy Simulations of Combustor Liner Flows | Argonne Leadership

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

    Computing Facility droplets. Large Eddy Simulations of a GE CFM combustor, temperature distribution and liquid fuel droplets. Anne Dord, GE Global Research Large Eddy Simulations of Combustor Liner Flows PI Name: Anne Dord PI Email: anne.dord@ge.com Institution: GE Global Research Allocation Program: INCITE Allocation Hours at ALCF: 75 Million Year: 2014 Research Domain: Engineering Aviation gas turbine engines are an essential part of the transportation industry. In 2012, the commercial

  5. Large Eddy Simulations of Combustor Liner Flows | Argonne Leadership

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

    Computing Facility droplets Large Eddy Simulations of a GE CFM combustor, temperature distribution and liquid fuel droplets. Credit: Anne Dord, GE Global Research Large Eddy Simulations of Combustor Liner Flows PI Name: Anne Dord PI Email: anne.dord@ge.com Institution: GE Global Research Allocation Program: INCITE Allocation Hours at ALCF: 89 Million Year: 2015 Research Domain: Engineering In 2012, the commercial aviation industry spent an estimated $207 billion on fuel, or about 33 percent

  6. Large Scale Computing and Storage Requirements for Biological and

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

    Environmental Research: Target 2014 Large Scale Computing and Storage Requirements for Biological and Environmental Research: Target 2014 BERFrontcover.png A BER / ASCR / NERSC Workshop May 7-8, 2009 Final Report Large Scale Computing and Storage Requirements for Biological and Environmental Research, Report of the Joint BER / NERSC Workshop Conducted May 7-8, 2009 Rockville, MD Goals This workshop was jointly organized by the Department of Energy's Office of Biological & Environmental

  7. Large Scale Computing and Storage Requirements for Fusion Energy Sciences:

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

    Target 2014 High Energy Physics (HEP) Nuclear Physics (NP) Overview Published Reports Case Study FAQs NERSC HPC Achievement Awards Share Your Research User Submitted Research Citations NERSC Citations Home » Science at NERSC » HPC Requirements Reviews » Requirements Reviews: Target 2014 » Fusion Energy Sciences (FES) Large Scale Computing and Storage Requirements for Fusion Energy Sciences: Target 2014 FESFrontcover.png An FES / ASCR / NERSC Workshop August 3-4, 2010 Final Report Large

  8. Large Scale Computing and Storage Requirements for Nuclear Physics: Target

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

    2014 Large Scale Computing and Storage Requirements for Nuclear Physics: Target 2014 NPFrontcover.png May 26-27, 2011 Hyatt Regency Bethesda One Bethesda Metro Center (7400 Wisconsin Ave) Bethesda, Maryland, USA 20814 Final Report Large Scale Computing and Storage Requirements for Nuclear Physics Research, Report of the Joint NP / NERSC Workshop Conducted May 26-27, 2011 Bethesda, MD Sponsored by the U.S. Department of Energy Office of Science, Office of Advanced Scientific Computing

  9. Large Scale Production Computing and Storage Requirements for Fusion Energy

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

    Sciences: Target 2017 Large Scale Production Computing and Storage Requirements for Fusion Energy Sciences: Target 2017 The NERSC Program Requirements Review "Large Scale Production Computing and Storage Requirements for Fusion Energy Sciences" is organized by the Department of Energy's Office of Fusion Energy Sciences (FES), Office of Advanced Scientific Computing Research (ASCR), and the National Energy Research Scientific Computing Center (NERSC). The review's goal is to

  10. Large Scale Production Computing and Storage Requirements for High Energy

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

    Physics: Target 2017 Large Scale Production Computing and Storage Requirements for High Energy Physics: Target 2017 HEPlogo.jpg The NERSC Program Requirements Review "Large Scale Computing and Storage Requirements for High Energy Physics" is organized by the Department of Energy's Office of High Energy Physics (HEP), Office of Advanced Scientific Computing Research (ASCR), and the National Energy Research Scientific Computing Center (NERSC). The review's goal is to characterize

  11. Assessment of Vehicle Sizing, Energy Consumption and Cost through Large

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

    Scale Simulation of Advanced Vehicle Technologies | Argonne National Laboratory Assessment of Vehicle Sizing, Energy Consumption and Cost through Large Scale Simulation of Advanced Vehicle Technologies Title Assessment of Vehicle Sizing, Energy Consumption and Cost through Large Scale Simulation of Advanced Vehicle Technologies Publication Type Report Year of Publication 2016 Authors Moawad, A, Kim, N, Shidore, N, Rousseau, A Institution Argonne National Laboratory City Argonne, IL USA

  12. Criticality concerns in cleaning large uranium hexafluoride cylinders

    SciTech Connect (OSTI)

    Sheaffer, M.K.; Keeton, S.C.; Lutz, H.F.

    1995-06-01

    Cleaning large cylinders used to transport low-enriched uranium hexafluoride (UF{sub 6}) presents several challenges to nuclear criticality safety. This paper presents a brief overview of the cleaning process, the criticality controls typically employed and their bases. Potential shortfalls in implementing these controls are highlighted, and a simple example to illustrate the difficulties in complying with the Double Contingency Principle is discussed. Finally, a summary of recommended criticality controls for large cylinder cleaning operations is presented.

  13. DOE Regional Partnership Begins Core Sampling for Large-Volume

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

    Sequestration Test | Department of Energy Begins Core Sampling for Large-Volume Sequestration Test DOE Regional Partnership Begins Core Sampling for Large-Volume Sequestration Test May 22, 2009 - 1:00pm Addthis Washington, DC - The Plains CO2 Reduction (PCOR) Partnership, one of seven members of the U.S. Department of Energy's Regional Carbon Sequestration Partnerships program, has begun collecting core samples from a new characterization well near Spectra Energy's Fort Nelson natural gas

  14. DOE's New Large Blade Test Facility in Massachusetts Completes First

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

    Commercial Blade Tests | Department of Energy DOE's New Large Blade Test Facility in Massachusetts Completes First Commercial Blade Tests DOE's New Large Blade Test Facility in Massachusetts Completes First Commercial Blade Tests December 19, 2011 - 3:15pm Addthis This is an excerpt from the Fourth Quarter 2011 edition of the Wind Program R&D Newsletter. Since opening its doors for business in May, the Wind Technology Testing Center (WTTC), in Boston, Massachusetts, has come up to full

  15. Technical feasibility of storage on large dish stirling systems. (Technical

    Office of Scientific and Technical Information (OSTI)

    Report) | SciTech Connect Technical feasibility of storage on large dish stirling systems. Citation Details In-Document Search Title: Technical feasibility of storage on large dish stirling systems. Authors: Andraka, Charles E. ; Rawlinson, Kim Scott ; Siegel, Nathan Phillip [1] + Show Author Affiliations (Bucknell University, Lewisburg, PA) Publication Date: 2012-09-01 OSTI Identifier: 1055585 Report Number(s): SAND2012-8352 DOE Contract Number: AC04-94AL85000 Resource Type: Technical

  16. Cosmological Simulations for Large-Scale Sky Surveys | Argonne Leadership

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

    Computing Facility Cosmological Simulations for Large-Scale Sky Surveys PI Name: Salman Habib PI Email: habib@anl.gov Institution: Argonne National Laboratory Allocation Program: INCITE Allocation Hours at ALCF: 100 Million Year: 2014 Research Domain: Physics The next generation of large-scale sky surveys aims to establish a new regime of cosmic discovery through fundamental measurements of the universe's geometry and the growth of structure. The aim of this project is to accurately

  17. Building America Webinar: Opportunities in Large Data Collection and

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

    Analysis | Department of Energy Analysis Building America Webinar: Opportunities in Large Data Collection and Analysis This introductory presentation for the webinar held on April 16, 2014, gives an overview of the Building America program and the webinar. BA_Webinar_Intro_4-16-14.pdf (965.11 KB) More Documents & Publications Building America Webinar: Opportunities in Large Data Collection and Analysis Building America Webinar: Retrofitting Central Space Conditioning Strategies for

  18. Global climate change: Mitigation opportunities high efficiency large chiller technology

    SciTech Connect (OSTI)

    Stanga, M.V.

    1997-12-31

    This paper, comprised of presentation viewgraphs, examines the impact of high efficiency large chiller technology on world electricity consumption and carbon dioxide emissions. Background data are summarized, and sample calculations are presented. Calculations show that presently available high energy efficiency chiller technology has the ability to substantially reduce energy consumption from large chillers. If this technology is widely implemented on a global basis, it could reduce carbon dioxide emissions by 65 million tons by 2010.

  19. COLLOQUIUM: Large Scale Superconducting Magnets for Variety of Applications

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

    | Princeton Plasma Physics Lab October 15, 2014, 4:00pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: Large Scale Superconducting Magnets for Variety of Applications Professor Joseph Minervini Massachusetts Institute of Technology Presentation: PDF icon Superconducting_Magnet_Technology_for_Fusion_and_Large_Scale_Applications.pdf Over the past several decades the U. S. magnetic confinement fusion program, working in collaboration with international partners, has developed superconductor and

  20. The Phoenix series large scale LNG pool fire experiments.

    SciTech Connect (OSTI)

    Simpson, Richard B.; Jensen, Richard Pearson; Demosthenous, Byron; Luketa, Anay Josephine; Ricks, Allen Joseph; Hightower, Marion Michael; Blanchat, Thomas K.; Helmick, Paul H.; Tieszen, Sheldon Robert; Deola, Regina Anne; Mercier, Jeffrey Alan; Suo-Anttila, Jill Marie; Miller, Timothy J.

    2010-12-01

    The increasing demand for natural gas could increase the number and frequency of Liquefied Natural Gas (LNG) tanker deliveries to ports across the United States. Because of the increasing number of shipments and the number of possible new facilities, concerns about the potential safety of the public and property from an accidental, and even more importantly intentional spills, have increased. While improvements have been made over the past decade in assessing hazards from LNG spills, the existing experimental data is much smaller in size and scale than many postulated large accidental and intentional spills. Since the physics and hazards from a fire change with fire size, there are concerns about the adequacy of current hazard prediction techniques for large LNG spills and fires. To address these concerns, Congress funded the Department of Energy (DOE) in 2008 to conduct a series of laboratory and large-scale LNG pool fire experiments at Sandia National Laboratories (Sandia) in Albuquerque, New Mexico. This report presents the test data and results of both sets of fire experiments. A series of five reduced-scale (gas burner) tests (yielding 27 sets of data) were conducted in 2007 and 2008 at Sandia's Thermal Test Complex (TTC) to assess flame height to fire diameter ratios as a function of nondimensional heat release rates for extrapolation to large-scale LNG fires. The large-scale LNG pool fire experiments were conducted in a 120 m diameter pond specially designed and constructed in Sandia's Area III large-scale test complex. Two fire tests of LNG spills of 21 and 81 m in diameter were conducted in 2009 to improve the understanding of flame height, smoke production, and burn rate and therefore the physics and hazards of large LNG spills and fires.

  1. RF system models for the CERN Large Hadron Collider with application to longitudinal dynamics

    SciTech Connect (OSTI)

    Mastorides, T.; Rivetta, C.; Fox, J.D.; Winkle, D.Van; Baudrenghien, P.; /CERN

    2011-03-03

    The LHC RF station-beam interaction strongly influences the longitudinal beam dynamics, both single bunch and collective effects. Non-linearities and noise generated within the Radio Frequency (RF) accelerating system interact with the beam and contribute to beam motion and longitudinal emittance blowup. Thus, the noise power spectrum of the RF accelerating voltage strongly affects the longitudinal beam distribution. Furthermore, the coupled-bunch instabilities are also directly affected by the RF components and the configuration of the Low Level RF (LLRF) feedback loops. In this work we present a formalism relating the longitudinal beam dynamics with the RF system configurations, an estimation of collective effects stability margins, and an evaluation of longitudinal sensitivity to various LLRF parameters and configurations.

  2. Extreme argon purity in a large, non-evacuated cryostat

    SciTech Connect (OSTI)

    Tope, Terry; Adamowski, Mark; Carls, B.; Hahn, A.; Jaskierny, W.; Jostlein, H.; Kendziora, C.; Lockwitz, S.; Pahlka, B.; Plunkett, R.; Pordes, S.; Rebel, B.; Schmitt, R.; Skup, E.; Stancari, M.; Yang, T.

    2014-01-29

    Liquid Argon Time Projection Chambers (LArTPCs) show promise as scalable devices for the large detectors needed for long-baseline neutrino oscillation physics. Over the last several years at Fermilab a staged approach to developing the technology for large detectors has been developed. The TPC detectors require ultra-pure liquid argon with respect to electronegative contaminants such as oxygen and water. The tolerable electronegative contamination level may be as pure as 60 parts per trillion of oxygen. Three liquid argon cryostats operated at Fermilab have achieved the extreme purity required by TPCs. These three cryostats used evacuation to remove atmospheric contaminants as the first purification step prior to filling with liquid argon. Future physics experiments may require very large detectors with tens of kilotonnes of liquid argon mass. The capability to evacuate such large cryostats adds significant cost to the cryostat itself in addition to the cost of a large scale vacuum pumping system. This paper describes a 30 ton liquid argon cryostat at Fermilab which uses purging to remove atmospheric contaminants instead of evacuation as the first purification step. This cryostat has achieved electronegative contamination levels better than 60 parts per trillion of oxygen equivalent. The results of this liquid argon purity demonstration will strongly influence the design of future TPC cryostats.

  3. Rapid Determination Of Radiostrontium In Large Soil Samples

    SciTech Connect (OSTI)

    Maxwell, Sherrod L.; Culligan, Brian K.; Shaw, Patrick J.

    2012-05-24

    A new method for the determination of radiostrontium in large soil samples has been developed at the Savannah River Environmental Laboratory (Aiken, SC, USA) that allows rapid preconcentration and separation of strontium in large soil samples for the measurement of strontium isotopes by gas flow proportional counting. The need for rapid analyses in the event of a Radiological Dispersive Device (RDD) or Improvised Nuclear Device (IND) event is well-known. In addition, the recent accident at Fukushima Nuclear Power Plant in March, 2011 reinforces the need to have rapid analyses for radionuclides in environmental samples in the event of a nuclear accident. The method employs a novel pre-concentration step that utilizes an iron hydroxide precipitation (enhanced with calcium phosphate) followed by a final calcium fluoride precipitation to remove silicates and other matrix components. The pre-concentration steps, in combination with a rapid Sr Resin separation using vacuum box technology, allow very large soil samples to be analyzed for {sup 89,90}Sr using gas flow proportional counting with a lower method detection limit. The calcium fluoride precipitation eliminates column flow problems typically associated with large amounts of silicates in large soil samples.

  4. EINSTEIN'S SIGNATURE IN COSMOLOGICAL LARGE-SCALE STRUCTURE

    SciTech Connect (OSTI)

    Bruni, Marco; Hidalgo, Juan Carlos; Wands, David

    2014-10-10

    We show how the nonlinearity of general relativity generates a characteristic nonGaussian signal in cosmological large-scale structure that we calculate at all perturbative orders in a large-scale limit. Newtonian gravity and general relativity provide complementary theoretical frameworks for modeling large-scale structure in ?CDM cosmology; a relativistic approach is essential to determine initial conditions, which can then be used in Newtonian simulations studying the nonlinear evolution of the matter density. Most inflationary models in the very early universe predict an almost Gaussian distribution for the primordial metric perturbation, ?. However, we argue that it is the Ricci curvature of comoving-orthogonal spatial hypersurfaces, R, that drives structure formation at large scales. We show how the nonlinear relation between the spatial curvature, R, and the metric perturbation, ?, translates into a specific nonGaussian contribution to the initial comoving matter density that we calculate for the simple case of an initially Gaussian ?. Our analysis shows the nonlinear signature of Einstein's gravity in large-scale structure.

  5. On-demand Overlay Networks for Large Scientific Data Transfers

    SciTech Connect (OSTI)

    Ramakrishnan, Lavanya; Guok, Chin; Jackson, Keith; Kissel, Ezra; Swany, D. Martin; Agarwal, Deborah

    2009-10-12

    Large scale scientific data transfers are central to scientific processes. Data from large experimental facilities have to be moved to local institutions for analysis or often data needs to be moved between local clusters and large supercomputing centers. In this paper, we propose and evaluate a network overlay architecture to enable highthroughput, on-demand, coordinated data transfers over wide-area networks. Our work leverages Phoebus and On-demand Secure Circuits and AdvanceReservation System (OSCARS) to provide high performance wide-area network connections. OSCARS enables dynamic provisioning of network paths with guaranteed bandwidth and Phoebus enables the coordination and effective utilization of the OSCARS network paths. Our evaluation shows that this approach leads to improved end-to-end data transfer throughput with minimal overheads. The achievedthroughput using our overlay was limited only by the ability of the end hosts to sink the data.

  6. Nuclear-pumped lasers for large-scale applications

    SciTech Connect (OSTI)

    Anderson, R.E.; Leonard, E.M.; Shea, R.F.; Berggren, R.R.

    1989-05-01

    Efficient initiation of large-volume chemical lasers may be achieved by neutron induced reactions which produce charged particles in the final state. When a burst mode nuclear reactor is used as the neutron source, both a sufficiently intense neutron flux and a sufficiently short initiation pulse may be possible. Proof-of-principle experiments are planned to demonstrate lasing in a direct nuclear-pumped large-volume system; to study the effects of various neutron absorbing materials on laser performance; to study the effects of long initiation pulse lengths; to demonstrate the performance of large-scale optics and the beam quality that may be obtained; and to assess the performance of alternative designs of burst systems that increase the neutron output and burst repetition rate. 21 refs., 8 figs., 5 tabs.

  7. Nuclear-pumped lasers for large-scale applications

    SciTech Connect (OSTI)

    Anderson, R.E.; Leonard, E.M.; Shea, R.E.; Berggren, R.R.

    1988-01-01

    Efficient initiation of large-volume chemical lasers may be achieved by neutron induced reactions which produce charged particles in the final state. When a burst mode nuclear reactor is used as the neutron source, both a sufficiently intense neutron flux and a sufficient short initiation pulse may be possible. Proof-of-principle experiments are planned to demonstrate lasing in a direct nuclear-pumped large-volume system: to study the effects of various neutron absorbing materials on laser performance; to study the effects of long initiation pulse lengths; to determine the performance of large-scale optics and the beam quality that may bo obtained; and to assess the performance of alternative designs of burst systems that increase the neutron output and burst repetition rate. 21 refs., 7 figs., 5 tabs.

  8. Method to produce large, uniform hollow spherical shells

    DOE Patents [OSTI]

    Hendricks, C.D.

    1983-09-26

    The invention is a method to produce large uniform hollow spherical shells by (1) forming uniform size drops of heat decomposable or vaporizable material, (2) evaporating the drops to form dried particles, (3) coating the dried particles with a layer of shell forming material and (4) heating the composite particles to melt the outer layer and to decompose or vaporize the inner particle to form an expanding inner gas bubble. The expanding gas bubble forms the molten outer layer into a shell of relatively large diameter. By cycling the temperature and pressure on the molten shell, nonuniformities in wall thickness can be reduced. The method of the invention is utilized to produce large uniform spherical shells, in the millimeter to centimeter diameter size range, from a variety of materials and of high quality, including sphericity, concentricity and surface smoothness, for use as laser fusion or other inertial confinement fusion targets as well as other applications.

  9. Large-pore catalysts for hydroprocessing of residual oils

    SciTech Connect (OSTI)

    Ying, Z.S.; Gevert, B.; Otterstedt, J.E.; Sterte, J.

    1995-05-01

    Hydroprocessing catalysts were prepared using fibrillar alumina and attapulgite as carrier materials and nickel and molybdenum as active substances. With fibrillar alumina as primary particles, a carrier material was obtained which combined a large surface area (138 m{sup 2}/g) with a large average pore diameter (252 {angstrom}). Due to side-by-side association of the fibers, attapulgite did not yield a catalyst carrier with as large pores as was expected. The catalysts were tested for hydroprocessing of an atmospheric petroleum resid, and the results were compared with those obtained for a commercial catalyst with similar loading of nickel and molybdenum. The catalyst prepared using fibrillar alumina as carrier material was more active than the commercial catalyst for hydrodemetallization, equally active for hydrodesulfurization, and less active for hydrodenitrogenation. The catalyst prepared using attapulgite as carrier material was inferior to the other two catalysts in all respects.

  10. Highly stretchable miniature strain sensor for large dynamic strain measurement

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

    Song, Bo; Yao, Shurong; Nie, Xu; Yu, Xun; Blecke, Jill

    2016-01-01

    In this paper, a new type of highly stretchable strain sensor was developed to measure large strains. The sensor was based on the piezo-resistive response of carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composite thin films. The piezo-resistive response of CNT composite gives accurate strain measurement with high frequency response, while the ultra-soft PDMS matrix provides high flexibility and ductility for large strain measurement. Experimental results show that the CNT/PDMS sensor measures large strains (up to 8 %) with an excellent linearity and a fast frequency response. The new miniature strain sensor also exhibits much higher sensitivities than the conventional foil strain gages,more » as its gauge factor is 500 times of that of the conventional foil strain gages.« less

  11. Highly stretchable miniature strain sensor for large dynamic strain measurement

    SciTech Connect (OSTI)

    Song, Bo; Yao, Shurong; Nie, Xu; Yu, Xun; Blecke, Jill

    2016-01-01

    In this paper, a new type of highly stretchable strain sensor was developed to measure large strains. The sensor was based on the piezo-resistive response of carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composite thin films. The piezo-resistive response of CNT composite gives accurate strain measurement with high frequency response, while the ultra-soft PDMS matrix provides high flexibility and ductility for large strain measurement. Experimental results show that the CNT/PDMS sensor measures large strains (up to 8 %) with an excellent linearity and a fast frequency response. The new miniature strain sensor also exhibits much higher sensitivities than the conventional foil strain gages, as its gauge factor is 500 times of that of the conventional foil strain gages.

  12. Large-Eddy Simulation of Wind-Plant Aerodynamics: Preprint

    SciTech Connect (OSTI)

    Churchfield, M. J.; Lee, S.; Moriarty, P. J.; Martinez, L. A.; Leonardi, S.; Vijayakumar, G.; Brasseur, J. G.

    2012-01-01

    In this work, we present results of a large-eddy simulation of the 48 multi-megawatt turbines composing the Lillgrund wind plant. Turbulent inflow wind is created by performing an atmospheric boundary layer precursor simulation and turbines are modeled using a rotating, variable-speed actuator line representation. The motivation for this work is that few others have done wind plant large-eddy simulations with a substantial number of turbines, and the methods for carrying out the simulations are varied. We wish to draw upon the strengths of the existing simulations and our growing atmospheric large-eddy simulation capability to create a sound methodology for performing this type of simulation. We have used the OpenFOAM CFD toolbox to create our solver.

  13. Large-area metallic photonic lattices for military applications.

    SciTech Connect (OSTI)

    Luk, Ting Shan

    2007-11-01

    In this project we developed photonic crystal modeling capability and fabrication technology that is scaleable to large area. An intelligent optimization code was developed to find the optimal structure for the desired spectral response. In terms of fabrication, an exhaustive survey of fabrication techniques that would meet the large area requirement was reduced to Deep X-ray Lithography (DXRL) and nano-imprint. Using DXRL, we fabricated a gold logpile photonic crystal in the <100> plane. For the nano-imprint technique, we fabricated a cubic array of gold squares. These two examples also represent two classes of metallic photonic crystal topologies, the connected network and cermet arrangement.

  14. Reduction of fire hazards on large mining equipment

    SciTech Connect (OSTI)

    Maria I. De Rosa

    2008-09-15

    Although standards and regulations are in place to prevent large mining equipment fires, recent analyses of mine accident data show that mining equipment fires still occur with alarming frequency and grave consequences, particularly at all surface mines and in underground metal/nonmetal mines. Recently technological advances in fire protection, combined with the statistical data on equipment fires, led NIOSH to reinvestigate this and to improve operator safety. NIOSH demonstrated that newly developed technologies, such as dual cab fire inerting systems and engine compartment fire barriers, can greatly enhance operator safety and lessen the damage of property during large mobile equipment fires. 10 refs., 5 figs.

  15. Finding Large Aperture Fractures in Geothermal Resource Areas Using A

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

    Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis | Department of Energy A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Fining Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic

  16. Exploiting Universality in Atoms with Large Scattering Lengths

    SciTech Connect (OSTI)

    Braaten, Eric

    2012-05-31

    The focus of this research project was atoms with scattering lengths that are large compared to the range of their interactions and which therefore exhibit universal behavior at sufficiently low energies. Recent dramatic advances in cooling atoms and in manipulating their scattering lengths have made this phenomenon of practical importance for controlling ultracold atoms and molecules. This research project was aimed at developing a systematically improvable method for calculating few-body observables for atoms with large scattering lengths starting from the universal results as a first approximation. Significant progress towards this goal was made during the five years of the project.

  17. DOE Completes Large-Scale Carbon Sequestration Project Awards | Department

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

    of Energy Large-Scale Carbon Sequestration Project Awards DOE Completes Large-Scale Carbon Sequestration Project Awards November 17, 2008 - 4:58pm Addthis Regional Partner to Demonstrate Safe and Permanent Storage of 2 Million Tons of CO2 at Wyoming Site WASHINGTON, DC - Completing a series of awards through its Regional Carbon Sequestration Partnership Program, the U.S. Department of Energy (DOE) today awarded $66.9 million to the Big Sky Regional Carbon Sequestration Partnership for the

  18. TMD factorization and evolution at large $b_T$

    SciTech Connect (OSTI)

    Collins, John; Rogers, Ted

    2015-07-01

    In using transverse-momentum-dependent (TMD) parton densities and fragmentation functions, important non-perturbative information is at large transverse position $b_T$. This concerns both the TMD functions and their evolution. Fits to high energy data tend to predict too rapid evolution when extrapolated to low energies where larger values of $b_T$ dominate. I summarize a new analysis of the issues. It results in a proposal for much weaker $b_T$ dependence at large $b_T$ for the evolution kernel, while preserving the accuracy of the existing fits. The results are particularly important for using transverse-spin-dependent functions like the Sivers function.

  19. Mixing device for materials with large density differences

    DOE Patents [OSTI]

    Gregg, D.W.

    1994-08-16

    An auger-tube pump mixing device is disclosed for mixing materials with large density differences while maintaining low stirring RPM and low power consumption. The mixing device minimizes the formation of vortexes and minimizes the incorporation of small bubbles in the liquid during mixing. By avoiding the creation of a vortex the device provides efficient stirring of full containers without spillage over the edge. Also, the device solves the problem of effective mixing in vessels where the liquid height is large compared to the diameter. Because of the gentle stirring or mixing by the device, it has application for biomedical uses where cell damage is to be avoided. 2 figs.

  20. Mixing device for materials with large density differences

    DOE Patents [OSTI]

    Gregg, David W.

    1994-01-01

    An auger-tube pump mixing device for mixing materials with large density differences while maintaining low stirring RPM and low power consumption. The mixing device minimizes the formation of vortexes and minimizes the incorporation of small bubbles in the liquid during mixing. By avoiding the creation of a vortex the device provides efficient stirring of full containers without spillage over the edge. Also, the device solves the problem of effective mixing in vessels where the liquid height is large compared to the diameter. Because of the gentle stirring or mixing by the device, it has application for biomedical uses where cell damage is to be avoided.