Sample records for investigating extreme ultraviolet

  1. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes | NationalCurriculum Introduction toLucasInvestigating Extreme

  2. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergyBPA-Film-Collection SignInvestigating Extreme

  3. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergyBPA-Film-CollectionInvestigating Extreme

  4. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergyBPA-Film-Collection SignInvestigating

  5. Extreme ultraviolet lithography machine

    DOE Patents [OSTI]

    Tichenor, Daniel A. (Castro Valley, CA); Kubiak, Glenn D. (Livermore, CA); Haney, Steven J. (Tracy, CA); Sweeney, Donald W. (San Ramon, CA)

    2000-01-01T23:59:59.000Z

    An extreme ultraviolet lithography (EUVL) machine or system for producing integrated circuit (IC) components, such as transistors, formed on a substrate. The EUVL machine utilizes a laser plasma point source directed via an optical arrangement onto a mask or reticle which is reflected by a multiple mirror system onto the substrate or target. The EUVL machine operates in the 10-14 nm wavelength soft x-ray photon. Basically the EUV machine includes an evacuated source chamber, an evacuated main or project chamber interconnected by a transport tube arrangement, wherein a laser beam is directed into a plasma generator which produces an illumination beam which is directed by optics from the source chamber through the connecting tube, into the projection chamber, and onto the reticle or mask, from which a patterned beam is reflected by optics in a projection optics (PO) box mounted in the main or projection chamber onto the substrate. In one embodiment of a EUVL machine, nine optical components are utilized, with four of the optical components located in the PO box. The main or projection chamber includes vibration isolators for the PO box and a vibration isolator mounting for the substrate, with the main or projection chamber being mounted on a support structure and being isolated.

  6. Method for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Felter, T. E. (Livermore, CA); Kubiak, Glenn D. (Livermore, CA)

    1999-01-01T23:59:59.000Z

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods.

  7. Method for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Felter, T. E. (727 Clara St., Livermore, Alameda County, CA 94550); Kubiak, G. D. (475 Maple St., Livermore, Alameda County, CA 94550)

    2000-01-01T23:59:59.000Z

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods.

  8. Solar Dynamics Observatory/ Extreme Ultraviolet Variability Experiment

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Solar Dynamics Observatory/ EVE Extreme Ultraviolet Variability Experiment Frequently Asked and model solar extreme ultraviolet irradiance variations due to solar flares, solar rotation, and solar and structure of the Sun. What is solar variability? Solar radiation varies on all time scales ranging from

  9. Photoresist composition for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Felter, T. E. (Alameda County, CA); Kubiak, G. D. (Alameda County, CA)

    1999-01-01T23:59:59.000Z

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods. A photoresist composition for extreme ultraviolet radiation of boron carbide polymers, hydrochlorocarbons and mixtures thereof.

  10. Comparing Vacuum and Extreme Ultraviolet Radiation for Postionization of Laser Desorbed Neutrals from Bacterial Biofilms and Organic Fullerene

    E-Print Network [OSTI]

    Gaspera, Gerald L.

    2011-01-01T23:59:59.000Z

    Laboratory, USA Comparing Vacuum and Extreme Ultravioletradiation, extreme ultraviolet, vacuum ultravioletAbstract Vacuum and extreme ultraviolet radiation from 8 -

  11. Reflective masks for extreme ultraviolet lithography

    SciTech Connect (OSTI)

    Nguyen, Khanh Bao

    1994-05-01T23:59:59.000Z

    Extreme ultraviolet lithographic masks are made by patterning multilayer reflective coatings with high normal incidence reflectivity. Masks can be patterned by depositing a patterned absorber layer above the coating or by etching the pattern directly into the coating itself. Electromagnetic simulations showed that absorber-overlayer masks have superior imaging characteristics over etched masks (less sensitive to incident angles and pattern profiles). In an EUVL absorber overlayer mask, defects can occur in the mask substrate, reflective coating, and absorber pattern. Electromagnetic simulations showed that substrate defects cause the most severe image degradation. A printability study of substrate defects for absorber overlayer masks showed that printability of 25 nm high substrate defects are comparable to defects in optical lithography. Simulations also indicated that the manner in which the defects are covered by multilayer reflective coatings can affect printability. Coverage profiles that result in large lateral spreading of defect geometries amplify the printability of the defects by increasing their effective sizes. Coverage profiles of Mo/Si coatings deposited above defects were studied by atomic force microscopy and TEM. Results showed that lateral spread of defect geometry is proportional to height. Undercut at defect also increases the lateral spread. Reductions in defect heights were observed for 0.15 {mu}m wide defect lines. A long-term study of Mo/Si coating reflectivity revealed that Mo/Si coatings with Mo as the top layer suffer significant reductions in reflectivity over time due to oxidation.

  12. THORIUM-BASED MIRRORS IN THE EXTREME ULTRAVIOLET Nicole Farnsworth

    E-Print Network [OSTI]

    Hart, Gus

    THORIUM-BASED MIRRORS IN THE EXTREME ULTRAVIOLET by Nicole Farnsworth Submitted to Brigham Young Ultraviolet and Thorium-based Mirrors . . . 1 1.2 Project Background the Optical Constants of Thorium Oxide 34 3.1 Reflectance and Transmittance Measurements

  13. 620 OPTICS LETTERS / Vol. 29, No. 6 / March 15, 2004 Damage to extreme-ultraviolet Sc Si multilayer mirrors

    E-Print Network [OSTI]

    Rocca, Jorge J.

    620 OPTICS LETTERS / Vol. 29, No. 6 / March 15, 2004 Damage to extreme-ultraviolet Sc Si multilayer, Russia Received August 21, 2003 The damage threshold and damage mechanism of extreme-ultraviolet Sc Si multilayer mirror coatings are investigated with focused nanosecond pulses at 46.9-nm radiation from

  14. Method for generating extreme ultraviolet with mather-type plasma accelerators for use in Extreme Ultraviolet Lithography

    DOE Patents [OSTI]

    Hassanein, Ahmed (Bolingbrook, IL); Konkashbaev, Isak (Bolingbrook, IL)

    2006-10-03T23:59:59.000Z

    A device and method for generating extremely short-wave ultraviolet electromagnetic wave uses two intersecting plasma beams generated by two plasma accelerators. The intersection of the two plasma beams emits electromagnetic radiation and in particular radiation in the extreme ultraviolet wavelength. In the preferred orientation two axially aligned counter streaming plasmas collide to produce an intense source of electromagnetic radiation at the 13.5 nm wavelength. The Mather type plasma accelerators can utilize tin, or lithium covered electrodes. Tin, lithium or xenon can be used as the photon emitting gas source.

  15. Efficient 13.5 nm extreme ultraviolet emission from Sn plasma irradiated by a long CO2 laser pulse

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    Efficient 13.5 nm extreme ultraviolet emission from Sn plasma irradiated by a long CO2 laser pulse-band 2% bandwidth conversion efficiency CE from a CO2 laser to 13.5 nm extreme ultraviolet EUV light was investigated for Sn plasma. It was found that high in-band CE, 2.6%, is consistently obtained using a CO2 laser

  16. Self-cleaning optic for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Klebanoff, Leonard E.; Stulen, Richard H.

    2003-12-16T23:59:59.000Z

    A multilayer reflective optic or mirror for lithographic applications, and particularly extreme ultraviolet (EUV) lithography, having a surface or "capping" layer which in combination with incident radiation and gaseous molecular species such as O.sub.2, H.sub.2, H.sub.2 O provides for continuous cleaning of carbon deposits from the optic surface. The metal capping layer is required to be oxidation resistant and capable of transmitting at least 90% of incident EUV radiation. Materials for the capping layer include Ru, Rh, Pd, Ir, Pt and Au and combinations thereof.

  17. MoRu/Be multilayers for extreme ultraviolet applications

    DOE Patents [OSTI]

    Bajt, Sasa C. (Livermore, CA); Wall, Mark A. (Stockton, CA)

    2001-01-01T23:59:59.000Z

    High reflectance, low intrinsic roughness and low stress multilayer systems for extreme ultraviolet (EUV) lithography comprise amorphous layers MoRu and crystalline Be layers. Reflectance greater than 70% has been demonstrated for MoRu/Be multilayers with 50 bilayer pairs. Optical throughput of MoRu/Be multilayers can be 30-40% higher than that of Mo/Be multilayer coatings. The throughput can be improved using a diffusion barrier to make sharper interfaces. A capping layer on the top surface of the multilayer improves the long-term reflectance and EUV radiation stability of the multilayer by forming a very thin native oxide that is water resistant.

  18. Broadband extreme ultraviolet probing of transient gratings in vanadium dioxide

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

    Sistrunk, Emily; Grilj, Jakob; Jeong, Jaewoo; Samant, Mahesh G.; Gray, Alexander X.; Dürr, Hermann A.; Parkin, Stuart S. P.; Gühr, Markus

    2015-01-01T23:59:59.000Z

    Nonlinear spectroscopy in the extreme ultraviolet (EUV) and soft x-ray spectral range offers the opportunity for element selective probing of ultrafast dynamics using core-valence transitions (Mukamel et al., Acc. Chem. Res. 42, 553 (2009)). We demonstrate a step on this path showing core-valence sensitivity in transient grating spectroscopy with EUV probing. We study the optically induced insulator-to-metal transition (IMT) of a VO? film with EUV diffraction from the optically excited sample. The VO? exhibits a change in the 3p-3d resonance of V accompanied by an acoustic response. Due to the broadband probing we are able to separate the two features.

  19. Extreme Ultra-Violet Spectroscopy of the Flaring Solar Chromosphere

    E-Print Network [OSTI]

    Milligan, Ryan O

    2015-01-01T23:59:59.000Z

    The extreme ultraviolet portion of the solar spectrum contains a wealth of diagnostic tools for probing the lower solar atmosphere in response to an injection of energy, particularly during the impulsive phase of solar flares. These include temperature and density sensitive line ratios, Doppler shifted emission lines and nonthermal broadening, abundance measurements, differential emission measure profiles, and continuum temperatures and energetics, among others. In this paper I shall review some of the advances made in recent years using these techniques, focusing primarily on studies that have utilized data from Hinode/EIS and SDO/EVE, while also providing some historical background and a summary of future spectroscopic instrumentation.

  20. Ablation of solids using a femtosecond extreme ultraviolet free electron laser

    SciTech Connect (OSTI)

    Stojanovic, N.; Linde, D. von der; Sokolowski-Tinten, K.; Zastrau, U.; Perner, F.; Foerster, E.; Sobierajski, R.; Nietubyc, R.; Jurek, M.; Klinger, D.; Pelka, J.; Krzywinski, J.; Juha, L; Cihelka, J.; Velyhan, A.; Koptyaev, S.; Hajkova, V.; Chalupsky, J.; Kuba, J.; Tschentscher, T. [Institut fuer Experimentelle Physik, Universitaet Duisburg-Essen, Lotharstrasse 1, 47048 Duisburg (Germany); Institut fuer Optik und Quantenelektronik, FSU Jena, 07743 Jena (Germany); Institute of Physics, PAS, Al. Lotnikov 32/46, 02-668 Warsaw (Poland); Institute of Physics, ASCR, 182 21 Prague (Czech Republic); Czech Technical University, 115 19 Prague (Czech Republic); Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22605 Hamburg (Germany)] (and others)

    2006-12-11T23:59:59.000Z

    The ablation of solids by high energy femtosecond pulses from an extreme ultraviolet (XUV) free electron laser has been investigated using picosecond optical imaging. The time-resolved measurements are supplemented by an analysis of the permanent structural surface modifications. Compared with femtosecond optical excitation, distinct differences in the material response are found which are attributed to the increased penetration depth of the XUV radiation and the absence of any absorption nonlinearities.

  1. Carbon contamination of extreme ultraviolet (EUV) mask and its effect on imaging

    E-Print Network [OSTI]

    Fan, Yu-Jen

    2009-01-01T23:59:59.000Z

    induced carbon contamination of extreme ultraviolet optics."potential LWR due to the contamination topography may be anet aI. , "Accelerated contamination testing of EUV masks."

  2. alpha-class extreme ultraviolet: Topics by E-print Network

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

    Vacuum Society. S0734-211X 00 02506-3 I. INTRODUCTION EUV lithography optics require 5 Solar Dynamics Observatory Extreme Ultraviolet Variability Experiment Geosciences Websites...

  3. Spectral Control of Emission from Tin Doped Targets for Extreme Ultraviolet Lithography

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    control of emissions from tin doped targets for extremearray (UTA) emission around 13.5 nm from solid density tinand tin doped foam targets. Extreme ultraviolet (EUV)

  4. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    with SEMATECH, an international semiconductor industry consortium, to create a unique Fresnel zone-plate microscope on Advanced Light Source Beamline 11.3.2 called the SEMATECH...

  5. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    light, opens the way to future generations of smaller, faster, and cheaper semiconductors. EUV lithography relies on specialized lenses made of curved mirrors with...

  6. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes | NationalCurriculum Introduction toLucas

  7. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergyBPA-Film-Collection Sign

  8. Investigating Extreme Ultraviolet Lithography Mask Defects

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergyBPA-Film-Collection

  9. Method for the protection of extreme ultraviolet lithography optics

    DOE Patents [OSTI]

    Grunow, Philip A.; Clift, Wayne M.; Klebanoff, Leonard E.

    2010-06-22T23:59:59.000Z

    A coating for the protection of optical surfaces exposed to a high energy erosive plasma. A gas that can be decomposed by the high energy plasma, such as the xenon plasma used for extreme ultraviolet lithography (EUVL), is injected into the EUVL machine. The decomposition products coat the optical surfaces with a protective coating maintained at less than about 100 .ANG. thick by periodic injections of the gas. Gases that can be used include hydrocarbon gases, particularly methane, PH.sub.3 and H.sub.2S. The use of PH.sub.3 and H.sub.2S is particularly advantageous since films of the plasma-induced decomposition products S and P cannot grow to greater than 10 .ANG. thick in a vacuum atmosphere such as found in an EUVL machine.

  10. Ultrafast Extreme Ultraviolet Induced Isomerization of Acetylene Cations

    SciTech Connect (OSTI)

    Jiang, Y. H.; Kurka, M.; Kuehnel, K. U.; Schroeter, C. D.; Moshammer, R. [Max-Planck-Institut fuer Kernphysik, 69117 Heidelberg (Germany); Rudenko, A.; Foucar, L. [Max-Planck Advanced Study Group at CFEL, 22607 Hamburg (Germany); Herrwerth, O.; Lezius, M.; Kling, M. F. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany); Tilborg, J. van; Belkacem, A. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Ueda, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 980-8577 Sendai (Japan); Duesterer, S.; Treusch, R. [DESY, 22607 Hamburg (Germany); Ullrich, J. [Max-Planck-Institut fuer Kernphysik, 69117 Heidelberg (Germany); Max-Planck Advanced Study Group at CFEL, 22607 Hamburg (Germany)

    2010-12-31T23:59:59.000Z

    Ultrafast isomerization of acetylene cations ([HC=CH]{sup +}) in the low-lying excited A{sup 2}{Sigma}{sub g}{sup +} state, populated by the absorption of extreme ultraviolet (XUV) photons (38 eV), has been observed at the Free Electron Laser in Hamburg, (FLASH). Recording coincident fragments C{sup +}+CH{sub 2}{sup +} as a function of time between XUV-pump and -probe pulses, generated by a split-mirror device, we find an isomerization time of 52{+-}15 fs in a kinetic energy release (KER) window of 5.8

  11. Ultrafast Extreme Ultraviolet Induced Isomerization of Acetylene Cations

    SciTech Connect (OSTI)

    Jiang, Y.; Rudenko, Artem; Herrwerth, O.; Foucar, L.; Kurka, M.; Kuhnel, K.; Lezius, M.; Kling, Matthias; van Tilborg, Jeroen; Belkacem, Ali; Ueda, K.; Dusterer, S.; Treusch, R.; Schroter, Claus-Dieter; Moshammer, Robbert; Ullrich, Joachim

    2011-06-17T23:59:59.000Z

    Ultrafast isomerization of acetylene cations ([HC = CH]{sup +}) in the low-lying excited A{sup 2}{Sigma}{sub g}{sup +} state, populated by the absorption of extreme ultraviolet (XUV) photons (38 eV), has been observed at the Free Electron Laser in Hamburg, (FLASH). Recording coincident fragments C{sup +} + CH{sub 2}{sup +} as a function of time between XUV-pump and -probe pulses, generated by a split-mirror device, we find an isomerization time of 52 {+-} 15 fs in a kinetic energy release (KER) window of 5.8 < KER < 8 eV, providing clear evidence for the existence of a fast, nonradiative decay channel.

  12. Upgrade of absolute extreme ultraviolet diagnostic on J-TEXT

    SciTech Connect (OSTI)

    Zhang, X. L.; Cheng, Z. F., E-mail: chengfe@hust.edu.cn; Hou, S. Y.; Zhuang, G.; Luo, J. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-11-15T23:59:59.000Z

    The absolute extreme ultraviolet (AXUV) diagnostic system is used for radiation observation on J-TEXT tokamak [J. Zhang, G. Zhuang, Z. J. Wang, Y. H. Ding, X. Q. Zhang, and Y. J. Tang, Rev. Sci. Instrum. 81, 073509 (2010)]. The upgrade of the AXUV system is aimed to improve the spatial resolution and provide a three-dimensional image on J-TEXT. The new system consists of 12 AXUV arrays (4 AXUV16ELG arrays, 8 AXUV20ELG arrays). The spatial resolution in the cross-section is 21 mm for the AXUV16ELG arrays and 17 mm for the AXUV20ELG arrays. The pre-amplifier is also upgraded for a higher signal to noise ratio. By upgrading the AXUV imaging system, a more accurate observation on the radiation information is obtained.

  13. Extreme ultraviolet mask substrate surface roughness effects on lithography patterning

    SciTech Connect (OSTI)

    George, Simi; Naulleau, Patrick; Salmassi, Farhad; Mochi, Iacopo; Gullikson, Eric; Goldberg, Kenneth; Anderson, Erik

    2010-06-21T23:59:59.000Z

    In extreme ultraviolet lithography exposure systems, mask substrate roughness induced scatter contributes to LER at the image plane. In this paper, the impact of mask substrate roughness on image plane speckle is explicitly evaluated. A programmed roughness mask was used to study the correlation between mask roughness metrics and wafer plane aerial image inspection. We find that the roughness measurements by top surface topography profile do not provide complete information on the scatter related speckle that leads to LER at the image plane. We suggest at wavelength characterization by imaging and/or scatter measurements into different frequencies as an alternative for a more comprehensive metrology of the mask substrate/multilayer roughness effects.

  14. Table top nanopatterning with extreme ultraviolet laser illumination M.G. Capeluto c

    E-Print Network [OSTI]

    Rocca, Jorge J.

    Table top nanopatterning with extreme ultraviolet laser illumination M.G. Capeluto c , P. Wachulak practical table-top nanopatterning tools based on extreme ultraviolet lasers for nanotechnology applications. Ó 2007 Elsevier B.V. All rights reserved. Keywords: EUV lasers; Table top photolithography

  15. Sensitivity calibration of an imaging extreme ultraviolet spectrometer-detector system for determining the efficiency of broadband extreme ultraviolet sources

    SciTech Connect (OSTI)

    Fuchs, S.; Roedel, C.; Bierbach, J.; Paz, A. E.; Foerster, E.; Paulus, G. G. [Institute of Optics und Quantum Electronics, Friedrich-Schiller-University Jena (Germany); Helmholtz-Institute Jena (Germany); Krebs, M. [Institute of Applied Physics, Friedrich-Schiller-University Jena (Germany); Haedrich, S.; Limpert, J. [Helmholtz-Institute Jena (Germany); Institute of Applied Physics, Friedrich-Schiller-University Jena (Germany); Kuschel, S.; Wuensche, M.; Hilbert, V.; Zastrau, U. [Institute of Optics und Quantum Electronics, Friedrich-Schiller-University Jena (Germany)

    2013-02-15T23:59:59.000Z

    We report on the absolute sensitivity calibration of an extreme ultraviolet (XUV) spectrometer system that is frequently employed to study emission from short-pulse laser experiments. The XUV spectrometer, consisting of a toroidal mirror and a transmission grating, was characterized at a synchrotron source in respect of the ratio of the detected to the incident photon flux at photon energies ranging from 15.5 eV to 99 eV. The absolute calibration allows the determination of the XUV photon number emitted by laser-based XUV sources, e.g., high-harmonic generation from plasma surfaces or in gaseous media. We have demonstrated high-harmonic generation in gases and plasma surfaces providing 2.3 {mu}W and {mu}J per harmonic using the respective generation mechanisms.

  16. Graphene defect formation by extreme ultraviolet generated photoelectrons

    SciTech Connect (OSTI)

    Gao, A., E-mail: a.gao@utwente.nl; Lee, C. J.; Bijkerk, F. [FOM-Dutch Institute for Fundamental Energy Research, Edisonbaan 14, 3439 MN Nieuwegein, The Netherlands and XUV Optics Group, MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands)

    2014-08-07T23:59:59.000Z

    We have studied the effect of photoelectrons on defect formation in graphene during extreme ultraviolet (EUV) irradiation. Assuming the major role of these low energy electrons, we have mimicked the process by using low energy primary electrons. Graphene is irradiated by an electron beam with energy lower than 80?eV. After e-beam irradiation, it is found that the D peak, I(D), appears in the Raman spectrum, indicating defect formation in graphene. The evolution of I(D)/I(G) follows the amorphization trajectory with increasing irradiation dose, indicating that graphene goes through a transformation from microcrystalline to nanocrystalline and then further to amorphous carbon. Further, irradiation of graphene with increased water partial pressure does not significantly change the Raman spectra, which suggests that, in the extremely low energy range, e-beam induced chemical reactions between residual water and graphene are not the dominant mechanism driving defect formation in graphene. Single layer graphene, partially suspended over holes was irradiated with EUV radiation. By comparing with the Raman results from e-beam irradiation, it is concluded that the photoelectrons, especially those from the valence band, contribute to defect formation in graphene during irradiation.

  17. AN EXTREME-ULTRAVIOLET WAVE ASSOCIATED WITH A SURGE

    SciTech Connect (OSTI)

    Zheng, Ruisheng; Jiang, Yunchun; Yang, Jiayan; Bi, Yi; Hong, Junchao; Yang, Bo; Yang, Dan, E-mail: zhrsh@ynao.ac.cn [National Astronomical Observatories/Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China)] [National Astronomical Observatories/Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China)

    2013-02-10T23:59:59.000Z

    Taking advantage of the high temporal and spatial resolution observations from the Solar Dynamics Observatory, we present an extreme-ultraviolet (EUV) wave associated with a surge on 2010 November 13. Due to the magnetic flux cancelation, some surges formed in the source active region (AR). The strongest surge produced our studied event. The surge was deflected by the nearby loops that connected to another AR, and disrupted the overlying loops that slowly expanded and eventually evolved into a weak coronal mass ejection (CME). The surge was likely associated with the core of the CME. The EUV wave happened after the surge deflected. The wave departed far from the flare center and showed a close location relative to the deflected surge. The wave propagated in a narrow angular extent, mainly in the ejection direction of the surge. The close timing and location relations between the EUV wave and the surge indicate that the wave was closely associated with the CME. The wave had a velocity of 310-350 km s{sup -1}, while the speeds of the surge and the expanding loops were about 130 and 150 km s{sup -1}, respectively. All of the results suggest that the EUV wave was a fast-mode wave and was most likely triggered by the weak CME.

  18. Performance of multilayer coated concave gratings in the extreme ultraviolet

    SciTech Connect (OSTI)

    Bixler, J.V.; Barbee, T.W. Jr.; Dietrich, D.D.

    1989-06-13T23:59:59.000Z

    Recent advances in multilayer structures for the Extreme Ultraviolet now make it possible to construct diffraction gratings in the wavelength range below 250 /angstrom/ which can be used for precision measurements using normal incidence spectrometers. We report results from two such gratings, one conventionally ruled and other holographically ruled. Both are one meter radius, 1200 lines per millimeter gratings coated with a molybdenum-silicon multilayer for use in the 150 /angstrom/ wavelength region. A McPherson 225 one meter normal incidence spectrometer with a Garton flash tube source and a film detector was used to test the resolution. Semiquantitative efficiency measurements were made by comparing the spectra with that produced by an osmium coated gratings. Oxygen lines in the wavelength region of interest (characteristic of the source) are easily detected and well resolved with both multilayer coated gratings. The same lines are faint or undetected with the osmium coated grating. Quantitative efficiency measurement were performed using a Penning source and a photon counting detector. 9 refs., 4 figs., 1 tab.

  19. Evolution of laser-produced Sn extreme ultraviolet source diameter for high-brightness source

    SciTech Connect (OSTI)

    Roy, Amitava, E-mail: roy@fzu.cz, E-mail: aroy@barc.gov.in [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), Utsunomiya University, Utsunomiya, Tochigi 321-8585 (Japan); HiLASE Centre, Institute of Physics ASCR, v.v.i., Za Radnicí 828, 25241 Dolní B?ežany (Czech Republic); Arai, Goki; Hara, Hiroyuki; Higashiguchi, Takeshi, E-mail: higashi@cc.utsunomiya-u.ac.jp [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), Utsunomiya University, Utsunomiya, Tochigi 321-8585 (Japan); Ohashi, Hayato [Graduate School of Science and Engineering for Research, University of Toyama, Toyama, Toyama 930-8555 (Japan); Sunahara, Atsushi [Institute for Laser Technology, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Li, Bowen [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Dunne, Padraig; O'Sullivan, Gerry [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Miura, Taisuke; Mocek, Tomas; Endo, Akira [HiLASE Centre, Institute of Physics ASCR, v.v.i., Za Radnicí 828, 25241 Dolní B?ežany (Czech Republic)

    2014-08-18T23:59:59.000Z

    We have investigated the effect of irradiation of solid Sn targets with laser pulses of sub-ns duration and sub-mJ energy on the diameter of the extreme ultraviolet (EUV) emitting region and source conversion efficiency. It was found that an in-band EUV source diameter as low as 18??m was produced due to the short scale length of a plasma produced by a sub-ns laser. Most of the EUV emission occurs in a narrow region with a plasma density close to the critical density value. Such EUV sources are suitable for high brightness and high repetition rate metrology applications.

  20. Influence of laser pulse duration on extreme ultraviolet and ion emission features from tin plasmas

    E-Print Network [OSTI]

    Harilal, S. S.

    Influence of laser pulse duration on extreme ultraviolet and ion emission features from tin plasmas ultraviolet (EUV) radiation from a laser pro- duced tin plasma has been studied extensively in recent years. The need for 13.5 nm wavelength and a regenerative target lead to the use of tin droplet targets.10 Hot tin

  1. Table-top Extreme Ultraviolet Laser Aerial Imaging of Lithographic Masks

    E-Print Network [OSTI]

    Brizuela, F.

    2012-01-01T23:59:59.000Z

    Table-top Extreme Ultraviolet Laser Aerial Imaging ofmasks realized using a table-top aerial imaging systembased on a table-top X=\\3.2 laser. © 2 0 0 9 Optical Society

  2. Extreme ultraviolet lithography: A few more pieces of the puzzle

    SciTech Connect (OSTI)

    Anderson, Christopher N.

    2009-05-20T23:59:59.000Z

    The work described in this dissertation has improved three essential components of extreme ultraviolet (EUV) lithography: exposure tools, photoresist, and metrology. Exposure tools. A field-averaging illumination stage is presented that enables nonuniform, high-coherence sources to be used in applications where highly uniform illumination is required. In an EUV implementation, it is shown that the illuminator achieves a 6.5% peak-to-valley intensity variation across the entire design field of view. In addition, a design for a stand-alone EUV printing tool capable of delivering 15 nm half-pitch sinusoidal fringes with available sources, gratings and nano-positioning stages is presented. It is shown that the proposed design delivers a near zero line-edge-rougness (LER) aerial image, something extremely attractive for the application of resist testing. Photoresist. Two new methods of quantifying the deprotection blur of EUV photoresists are described and experimentally demonstrated. The deprotection blur, LER, and sensitivity parameters of several EUV photoresists are quantified simultaneously as base weight percent, photoacid generator (PAG) weight percent, and post-exposure bake (PEB) temperature are varied. Two surprising results are found: (1) changing base weight percent does not significantly affect the deprotection blur of EUV photoresist, and (2) increasing PAG weight percent can simultaneously reduce LER and E-size in EUV photoresist. The latter result motivates the development of an EUV exposure statistics model that includes the effects of photon shot noise, the PAG spatial distribution, and the changing of the PAG distribution during the exposure. In addition, a shot noise + deprotection blur model is used to show that as deprotection blur becomes large relative to the size of the printed feature, LER reduction from improved counting statistics becomes dominated by an increase in LER due to reduced deprotection contrast. Metrology. Finally, this dissertation describes MOSAIC, a new wavefront metrology that enables complete wavefront recovery from print or aerial image based measurements. This new technique, based on measuring the local focal length of the optic at sampled positions in the pupil, recovers the curvature of the aberration and uses the curvature to recover the aberration itself. In a modeled EUV implementation, MOSAIC is shown to recover the SEMATECH Berkeley MET wavefront with a 4.2% RMS error: a 4% improvement over the reported errors of the original lateral shearing interferometry wavefront measurement.

  3. Carbon Contamination of Extreme Ultraviolet (EUV) Masks and its Effect on Imaging

    E-Print Network [OSTI]

    Carbon Contamination of Extreme Ultraviolet (EUV) Masks and its Effect on Imaging Yu-Jen Fan1 3. CXRO, Lawrence Berkeley National Laboratory, Berkeley CA ABSTRACT Carbon contamination of extreme and potential effects on imaging performance. In this work, a series of carbon contamination experiments were

  4. Time exposure performance of Mo-Au Gibbsian segregating alloys for extreme ultraviolet collector optics

    SciTech Connect (OSTI)

    Qiu Huatan; Srivastava, Shailendra N.; Thompson, Keith C.; Neumann, Martin J.; Ruzic, David N

    2008-05-01T23:59:59.000Z

    Successful implementation of extreme ultraviolet (EUV) lithography depends on research and progress toward minimizing collector optics degradation from intense plasma erosion and debris deposition. Thus studying the surface degradation process and implementing innovative methods, which could enhance the surface chemistry causing the mirrors to suffer less damage, is crucial for this technology development. A Mo-Au Gibbsian segregation (GS) alloy is deposited on Si using a dc dual-magnetron cosputtering system and the damage is investigated as a result of time dependent exposure in an EUV source. A thin Au segregating layer is maintained through segregation during exposure, even though overall erosion in the Mo-Au sample is taking place in the bulk. The reflective material, Mo, underneath the segregating layer is protected by this sacrificial layer, which is lost due to preferential sputtering. In addition to theoretical work, experimental results are presented on the effectiveness of the GS alloys to be used as potential EUV collector optics material.

  5. Laser triggered Z-pinch broadband extreme ultraviolet source for metrology

    SciTech Connect (OSTI)

    Tobin, I.; Lunney, J. G. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland)] [School of Physics, Trinity College Dublin, Dublin 2 (Ireland); Juschkin, L. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland) [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Department of Physics, RWTH Aachen University, Steinbachstr. 15 D-52074 Aachen (Germany); Sidelnikov, Y. [ISAN Institute of Spectroscopy, Fizicheskaya Str. 5, Troitsk, Moscow Region 142190 (Russian Federation)] [ISAN Institute of Spectroscopy, Fizicheskaya Str. 5, Troitsk, Moscow Region 142190 (Russian Federation); O'Reilly, F.; Sokell, E. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)] [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Sheridan, P. [Newlambda Technologies, UCD Science Centre North, Belfield, Dublin 4 (Ireland)] [Newlambda Technologies, UCD Science Centre North, Belfield, Dublin 4 (Ireland)

    2013-05-20T23:59:59.000Z

    We compare the extreme ultraviolet emission characteristics of tin and galinstan (atomic %: Ga: 78.35, In: 14.93, Sn: 6.72) between 10 nm and 18 nm in a laser-triggered discharge between liquid metal-coated electrodes. Over this wavelength range, the energy conversion efficiency for galinstan is approximately half that of tin, but the spectrum is less strongly peaked in the 13-15 nm region. The extreme ultraviolet source dimensions were 110 {+-} 25 {mu}m diameter and 500 {+-} 125 {mu}m length. The flatter spectrum, and -19 Degree-Sign C melting point, makes this galinstan discharge a relatively simple high radiance extreme ultraviolet light source for metrology and scientific applications.

  6. Carbon contamination and oxidation of Au surfaces under extreme ultraviolet radiation: An x-ray photoelectron spectroscopy study

    E-Print Network [OSTI]

    Harilal, S. S.

    Carbon contamination and oxidation of Au surfaces under extreme ultraviolet radiation: An x 2012) Extreme ultraviolet (EUV) radiation-induced carbon contamination and oxidation of Au surfaces modification during EUV exposure. XPS analysis showed that total carbon contamination (C 1s peak

  7. A simple transfer-optics system for an extreme-ultraviolet synchrotron beamline

    SciTech Connect (OSTI)

    Tarrio, C.; Grantham, S.; Vest, R.E.; Liu, K. [Electron and Optical Physics Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8410 (United States)

    2005-04-01T23:59:59.000Z

    Radiometric experiments often require comparatively high intensities in the extreme ultraviolet, in the microwatt range. The monochromators that provide the high throughput needed for these experiments, though, do not always allow for end stations to be switched out easily. At the National Institute of Standards and Technology Synchrotron Ultraviolet Radiation Facility, the only beamline with sufficient extreme-ultraviolet power has a multi-ton endstation, which cannot be moved. We will describe a set of transfer optics that allow the photon beam to be collimated and deflected through a port on the downstream end of the large chamber. This allowed an absolute cryogenic radiometer to be attached, with the entrance cavity underfilled. We will describe ray-tracing results and offer preliminary results of the radiometer-based throughput of the system.

  8. Effect of carbon contamination on the printing performance of extreme ultraviolet masks

    E-Print Network [OSTI]

    Effect of carbon contamination on the printing performance of extreme ultraviolet masks Yu-Jen Fan November 2009; accepted 2 February 2010; published 22 March 2010 Carbon contamination is a significant on imaging performance. Current carbon contamination research is primarily focused on the lifetime

  9. Flexible CO2 laser system for fundamental research related to an extreme ultraviolet lithography source

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    Flexible CO2 laser system for fundamental research related to an extreme ultraviolet lithography 2009; published online 10 December 2009 A CO2 laser system with flexible parameters was developed 1010 W/cm2 . Utilizing this CO2 MOPA laser system, high conversion efficiency from laser to in-band 2

  10. THE PREFLIGHT PHOTOMETRIC CALIBRATION OF THE EXTREME-ULTRAVIOLET IMAGING TELESCOPE EIT

    E-Print Network [OSTI]

    K. P. Dere; J. D. Moses; J. -p. Delaboudinière; J. Brunaud; C. Carabetian; J. -f. Hochedez; X. Y. Song; R. C. Catura; F. Clette

    1999-01-01T23:59:59.000Z

    Abstract. This paper presents the preflight photometric calibration of the Extreme-ultraviolet Imaging Telescope (EIT) aboard the Solar and Heliospheric Observatory (SOHO). The EIT consists of a Ritchey–Chrétien telescope with multilayer coatings applied to four quadrants of the primary and secondary mirrors, several filters and a backside-thinned CCD detector. The quadrants of the EIT

  11. Liquid-tin-jet laser-plasma extreme ultraviolet generation P. A. C. Jansson,a)

    E-Print Network [OSTI]

    Liquid-tin-jet laser-plasma extreme ultraviolet generation P. A. C. Jansson,a) B. A. M. Hansson, O spectral signatures. The system is demonstrated using tin Sn as the target due to its strong emission materials with new spectral signatures. As an example we use tin, motivated by its current interest for EUV

  12. Low-cost method for producing extreme ultraviolet lithography optics

    DOE Patents [OSTI]

    Folta, James A. (Livermore, CA); Montcalm, Claude (Fort Collins, CO); Taylor, John S. (Livermore, CA); Spiller, Eberhard A. (Mt. Kisco, NY)

    2003-11-21T23:59:59.000Z

    Spherical and non-spherical optical elements produced by standard optical figuring and polishing techniques are extremely expensive. Such surfaces can be cheaply produced by diamond turning; however, the roughness in the diamond turned surface prevent their use for EUV lithography. These ripples are smoothed with a coating of polyimide before applying a 60 period Mo/Si multilayer to reflect a wavelength of 134 .ANG. and have obtained peak reflectivities close to 63%. The savings in cost are about a factor of 100.

  13. Dynamics and manipulation of the dominant 13.5 nm in-band extreme ultraviolet emitting region of laser-produced Sn plasmas

    E-Print Network [OSTI]

    Yuspeh, Samuel Edward

    2011-01-01T23:59:59.000Z

    manufacturing (HVM) of semiconductor microchips with nodes 32 nm and below is extreme ultraviolet (EUV) lithography using laser

  14. Spectral-phase interferometry for direct electric-field reconstruction applied to seeded extreme-ultraviolet free-electron lasers

    E-Print Network [OSTI]

    Mahieu, Benoît; De Ninno, Giovanni; Dacasa, Hugo; Lozano, Magali; Rousseau, Jean-Philippe; Zeitoun, Philippe; Garzella, David; Merdji, Hamed

    2015-01-01T23:59:59.000Z

    We present a setup for complete characterization of femtosecond pulses generated by seeded free-electron lasers (FEL's) in the extreme-ultraviolet spectral region. Two delayed and spectrally shifted replicas are produced and used for spectral phase interferometry for direct electric field reconstruction (SPIDER). We show that it can be achieved by a simple arrangement of the seed laser. Temporal shape and phase obtained in FEL simulations are well retrieved by the SPIDER reconstruction, allowing to foresee the implementation of this diagnostic on existing and future sources. This will be a significant step towards an experimental investigation and control of FEL spectral phase.

  15. Method for plasma formation for extreme ultraviolet lithography-theta pinch

    DOE Patents [OSTI]

    Hassanein, Ahmed (Naperville, IL); Konkashbaev, Isak (Bolingbrook, IL); Rice, Bryan (Hillsboro, OR)

    2007-02-20T23:59:59.000Z

    A device and method for generating extremely short-wave ultraviolet electromagnetic wave, utilizing a theta pinch plasma generator to produce electromagnetic radiation in the range of 10 to 20 nm. The device comprises an axially aligned open-ended pinch chamber defining a plasma zone adapted to contain a plasma generating gas within the plasma zone; a means for generating a magnetic field radially outward of the open-ended pinch chamber to produce a discharge plasma from the plasma generating gas, thereby producing a electromagnetic wave in the extreme ultraviolet range; a collecting means in optical communication with the pinch chamber to collect the electromagnetic radiation; and focusing means in optical communication with the collecting means to concentrate the electromagnetic radiation.

  16. Damage of multilayer optics with varying capping layers induced by focused extreme ultraviolet beam

    SciTech Connect (OSTI)

    Jody Corso, Alain; Nicolosi, Piergiorgio; Nardello, Marco; Guglielmina Pelizzo, Maria [National Research Council of Italy, Institute for Photonics and Nanotechnology, via Trasea 7, 35131 Padova (Italy) [National Research Council of Italy, Institute for Photonics and Nanotechnology, via Trasea 7, 35131 Padova (Italy); Department of Information Engineering, University of Padova, via Gradenigo 6/B, 35131 Padova (Italy); Zuppella, Paola [National Research Council of Italy, Institute for Photonics and Nanotechnology, via Trasea 7, 35131 Padova (Italy)] [National Research Council of Italy, Institute for Photonics and Nanotechnology, via Trasea 7, 35131 Padova (Italy); Barkusky, Frank [Laser-Laboratorium Goettingen e.V, Goettingen (Germany) [Laser-Laboratorium Goettingen e.V, Goettingen (Germany); KLA-Tencor, 5 Technology Dr., Milpitas, California 95035 (United States); Mann, Klaus; Mueller, Matthias [Laser-Laboratorium Goettingen e.V, Goettingen (Germany)] [Laser-Laboratorium Goettingen e.V, Goettingen (Germany)

    2013-05-28T23:59:59.000Z

    Extreme ultraviolet Mo/Si multilayers protected by capping layers of different materials were exposed to 13.5 nm plasma source radiation generated with a table-top laser to study the irradiation damage mechanism. Morphology of single-shot damaged areas has been analyzed by means of atomic force microscopy. Threshold fluences were evaluated for each type of sample in order to determine the capability of the capping layer to protect the structure underneath.

  17. CITIUS: An infrared-extreme ultraviolet light source for fundamental and applied ultrafast science

    SciTech Connect (OSTI)

    Grazioli, C.; Gauthier, D.; Ivanov, R.; De Ninno, G. [Laboratory of Quantum Optics, University of Nova Gorica, Nova Gorica (Slovenia) [Laboratory of Quantum Optics, University of Nova Gorica, Nova Gorica (Slovenia); Elettra Sincrotrone Trieste, Trieste (Italy)] [Italy; Callegari, C.; Spezzani, C. [Elettra Sincrotrone Trieste, Trieste (Italy)] [Elettra Sincrotrone Trieste, Trieste (Italy); Ciavardini, A. [Sapienza University, Rome (Italy)] [Sapienza University, Rome (Italy); Coreno, M. [Elettra Sincrotrone Trieste, Trieste (Italy) [Elettra Sincrotrone Trieste, Trieste (Italy); Institute of Inorganic Methodologies and Plasmas (CNR-IMIP), Montelibretti, Roma (Italy); Frassetto, F.; Miotti, P.; Poletto, L. [Institute of Photonics and Nanotechnologies (CNR-IFN), Padova (Italy)] [Institute of Photonics and Nanotechnologies (CNR-IFN), Padova (Italy); Golob, D. [Kontrolni Sistemi d.o.o., Sežana (Slovenia)] [Kontrolni Sistemi d.o.o., Sežana (Slovenia); Kivimäki, A. [Institute of Materials Manufacturing (CNR-IOM), TASC Laboratory, Trieste (Italy)] [Institute of Materials Manufacturing (CNR-IOM), TASC Laboratory, Trieste (Italy); Mahieu, B. [Elettra Sincrotrone Trieste, Trieste (Italy) [Elettra Sincrotrone Trieste, Trieste (Italy); Service des Photons Atomes et Molécules, Commissariat à l'Energie Atomique, Centre d'Etudes de Saclay, Bâtiment 522, 91191 Gif-sur-Yvette (France); Bu?ar, B.; Merhar, M. [Laboratory of Mechanical Processing Technologies, University of Ljubljana, Ljubljana (Slovenia)] [Laboratory of Mechanical Processing Technologies, University of Ljubljana, Ljubljana (Slovenia); Polo, E. [Institute of Organic Synthesis and Photoreactivity (CNR-ISOF), Ferrara (Italy)] [Institute of Organic Synthesis and Photoreactivity (CNR-ISOF), Ferrara (Italy); Ressel, B. [Laboratory of Quantum Optics, University of Nova Gorica, Nova Gorica (Slovenia)] [Laboratory of Quantum Optics, University of Nova Gorica, Nova Gorica (Slovenia)

    2014-02-15T23:59:59.000Z

    We present the main features of CITIUS, a new light source for ultrafast science, generating tunable, intense, femtosecond pulses in the spectral range from infrared to extreme ultraviolet (XUV). The XUV pulses (about 10{sup 5}-10{sup 8} photons/pulse in the range 14-80 eV) are produced by laser-induced high-order harmonic generation in gas. This radiation is monochromatized by a time-preserving monochromator, also allowing one to work with high-resolution bandwidth selection. The tunable IR-UV pulses (10{sup 12}-10{sup 15} photons/pulse in the range 0.4-5.6 eV) are generated by an optical parametric amplifier, which is driven by a fraction of the same laser pulse that generates high order harmonics. The IR-UV and XUV pulses follow different optical paths and are eventually recombined on the sample for pump-probe experiments. We also present the results of two pump-probe experiments: with the first one, we fully characterized the temporal duration of harmonic pulses in the time-preserving configuration; with the second one, we demonstrated the possibility of using CITIUS for selective investigation of the ultra-fast dynamics of different elements in a magnetic compound.

  18. Update on the SEMATECH 0.5 NA Extreme-Ultraviolet Lithography (EUVL) Microfield Exposure Tool (MET)

    E-Print Network [OSTI]

    Cummings, Kevin

    2014-01-01T23:59:59.000Z

    eld Exposure Tools with 0.5 NA,” Proc. SPIE TBP (2014) [6]microexposure tool at 0.5 NA for sub-16 nm lithography,&Update on the SEMATECH 0.5 NA Extreme Ultraviolet

  19. Quasi-Coherent Oscillations in the Extreme Ultraviolet Flux of the Dwarf Nova SS Cygni

    E-Print Network [OSTI]

    Christopher W. Mauche

    1996-03-18T23:59:59.000Z

    Quasi-coherent oscillations have been detected in the extreme ultraviolet flux of the dwarf nova SS Cygni during observations with the Extreme Ultraviolet Explorer satellite of the rise and plateau phases of an anomalous outburst in 1993 August and a normal outburst in 1994 June/July. On both occasions, the oscillation turned on during the rise to outburst and persisted throughout the observation. During the 1993 outburst, the period of the oscillation fell from 9.3 s to 7.5 s over an interval of 4.4 days; during the 1994 outburst, the period fell from 8.9 s to 7.19 s (the shortest period ever observed in SS Cyg, or any other dwarf nova) within less than a day, and then rose to 8.0 s over an interval of 8.0 days. For both outbursts, the period $P$ of the oscillation was observed to correlate with the 75--120 \\AA \\ count rate $I_{\\rm EUV}$ according to $P\\propto I_{\\rm EUV}^{-0.094}$. A magnetospheric model is considered to reproduce this variation. It is found that an effective high-order multipole field is required, and that the field strength at the surface of the white dwarf is 0.1--1 MG. Such a field strength is at the lower extreme of those measured or inferred for bona fide magnetic cataclysmic variables.

  20. Passivating overcoat bilayer for multilayer reflective coatings for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Montcalm, Claude (Livermore, CA); Stearns, Daniel G. (Los Altos, CA); Vernon, Stephen P. (Pleasanton, CA)

    1999-01-01T23:59:59.000Z

    A passivating overcoat bilayer is used for multilayer reflective coatings for extreme ultraviolet (EUV) or soft x-ray applications to prevent oxidation and corrosion of the multilayer coating, thereby improving the EUV optical performance. The overcoat bilayer comprises a layer of silicon or beryllium underneath at least one top layer of an elemental or a compound material that resists oxidation and corrosion. Materials for the top layer include carbon, palladium, carbides, borides, nitrides, and oxides. The thicknesses of the two layers that make up the overcoat bilayer are optimized to produce the highest reflectance at the wavelength range of operation. Protective overcoat systems comprising three or more layers are also possible.

  1. Rare-earth plasma extreme ultraviolet sources at 6.5-6.7 nm

    SciTech Connect (OSTI)

    Otsuka, Takamitsu; Higashiguchi, Takeshi; Yugami, Noboru; Yatagai, Toyohiko [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); Kilbane, Deirdre; White, John; Dunne, Padraig; O'Sullivan, Gerry [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Jiang, Weihua [Department of Electrical Engineering, Nagaoka University of Technology, Kami-tomiokamachi 1603-1, Nagaoka, Niigata 940-2188 (Japan); Endo, Akira [Forschungszentrum Dresden, Bautzner Landstrs. 400, D-01328 Dresden (Germany)

    2010-09-13T23:59:59.000Z

    We have demonstrated a laser-produced plasma extreme ultraviolet source operating in the 6.5-6.7 nm region based on rare-earth targets of Gd and Tb coupled with a Mo/B{sub 4}C multilayer mirror. Multiply charged ions produce strong resonance emission lines, which combine to yield an intense unresolved transition array. The spectra of these resonant lines around 6.7 nm (in-band: 6.7 nm {+-}1%) suggest that the in-band emission increases with increased plasma volume by suppressing the plasma hydrodynamic expansion loss at an electron temperature of about 50 eV, resulting in maximized emission.

  2. Note: Enhancement of the extreme ultraviolet emission from a potassium plasma by dual laser irradiation

    SciTech Connect (OSTI)

    Higashiguchi, Takeshi, E-mail: higashi@cc.utsunomiya-u.ac.jp; Yamaguchi, Mami; Otsuka, Takamitsu; Nagata, Takeshi [Department of Advanced Interdisciplinary Sciences and Center for Optical Research (CORE), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 Japan (Japan); Ohashi, Hayato [Graduate School of Science and Engineering for Research, University of Toyama, Toyama, Toyama 930-8555 (Japan); Li, Bowen [School of Nuclear Science and Technology, Lanzhou University, Lanzhou, 730000 (China); School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); D’Arcy, Rebekah; Dunne, Padraig; O’Sullivan, Gerry [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)

    2014-09-15T23:59:59.000Z

    Emission spectra from multiply charged potassium ions ranging from K{sup 3+} to K{sup 5+} have been obtained in the extreme ultraviolet (EUV) spectral region. A strong emission feature peaking around 38?nm, corresponding to a photon energy of 32.6 eV, is the dominant spectral feature at time-averaged electron temperatures in the range of 8?12 eV. The variation of this emission with laser intensity and the effects of pre-pulses on the relative conversion efficiency (CE) have been explored experimentally and indicate that an enhancement of about 30% in EUV CE is readily attainable.

  3. Validity of the thin mask approximation in extreme ultraviolet mask roughness simulations

    SciTech Connect (OSTI)

    Naulleau, Patrick; George, Simi

    2011-01-26T23:59:59.000Z

    In the case of extreme ultraviolet (EUV) lithography, modeling has shown that reflector phase roughness on the lithographic mask is a significant concern due to the image plan speckle it causes and the resulting line-edge roughness on imaged features. Modeling results have recently been used to determine the requirements for future production worthy masks yielding the extremely stringent specification of 50 pm rms roughness. Owing to the scale of the problem in terms of memory requirements, past modeling results have all been based on the thin mask approximation. EUV masks, however, are inherently three dimensional in nature and thus the question arises as to the validity of the thin mask approximation. Here we directly compare image plane speckle calculation results using the fast two dimensional thin mask model to rigorous finite-difference time-domain results and find the two methods to be comparable.

  4. TWO TYPES OF EXTREME-ULTRAVIOLET BRIGHTENINGS IN AR 10926 OBSERVED BY HINODE/EIS

    SciTech Connect (OSTI)

    Lee, K.-S. [Department of Astronomy and Space Science, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Moon, Y.-J.; Choe, G. S. [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Kim, Sujin; Cho, Kyung-Suk [Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of); Imada, S., E-mail: lksun@khu.ac.kr [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara-shi, Kanagawa 252-5210 (Japan)

    2011-07-20T23:59:59.000Z

    We have investigated seven extreme-ultraviolet (EUV) brightenings in the active region AR 10926 on 2006 December 2 observed by the EUV Imaging Spectrometer on board the Hinode spacecraft. We have determined their Doppler velocities and non-thermal velocities from 15 EUV spectral lines (log T = 4.7 - 6.4) by fitting each line profile to a Gaussian function. The Doppler velocity maps for different temperatures are presented to show the height dependence of the Doppler shifts. It is found that the active region brightenings show two distinct Doppler shift patterns. The type 1 brightening shows a systematic increase of Doppler velocity from -68 km s{sup -1} (strong blueshift) at log T = 4.7 to -2 km s{sup -1} (weak blueshift) at log T = 6.4, while the type 2 brightenings have Doppler velocities in the range from -20 km s{sup -1} to 20 km s{sup -1}. The type 1 brightening point is considered to sit in an upward reconnection outflow whose speed decreases with height. In both types of brightenings, the non-thermal velocity is found to be significantly enhanced at log T = 5.8 compared to the background region. We have also determined electron densities from line ratios and derived temperatures from emission measure loci using the CHIANTI atomic database. The electron densities of all brightenings are comparable to typical values in active regions (log N{sub e} = 9.9-10.4). The emission measure loci plots indicate that these brightenings should be multi-thermal whereas the background is isothermal. The differential emission measure as a function of temperature shows multiple peaks in the EUV brightening regions, while it has only a single peak (log T = 6.0) in the background region. Using Michelson Doppler Imager magnetograms, we have found that the type 1 brightening is associated with a canceling magnetic feature with a flux canceling rate of 2.4 x 10{sup 18} Mx hr{sup -1}. We also found the canceling magnetic feature and chromospheric brightenings in the type 1 brightening from the Hinode SOT and Transition Region and Coronal Explorer data. This observation corroborates our argument that brightening is caused by magnetic reconnection in a low atmosphere.

  5. Repair of localized defects in multilayer-coated reticle blanks for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Stearns, Daniel G. (Los Altos, CA); Sweeney, Donald W. (San Ramon, CA); Mirkarimi, Paul B. (Sunol, CA)

    2004-11-23T23:59:59.000Z

    A method is provided for repairing defects in a multilayer coating layered onto a reticle blank used in an extreme ultraviolet lithography (EUVL) system. Using high lateral spatial resolution, energy is deposited in the multilayer coating in the vicinity of the defect. This can be accomplished using a focused electron beam, focused ion beam or a focused electromagnetic radiation. The absorbed energy will cause a structural modification of the film, producing a localized change in the film thickness. The change in film thickness can be controlled with sub-nanometer accuracy by adjusting the energy dose. The lateral spatial resolution of the thickness modification is controlled by the localization of the energy deposition. The film thickness is adjusted locally to correct the perturbation of the reflected field. For example, when the structural modification is a localized film contraction, the repair of a defect consists of flattening a mound or spreading out the sides of a depression.

  6. Extreme Ultraviolet Imaging of Three-dimensional Magnetic Reconnection in a Solar Eruption

    E-Print Network [OSTI]

    Sun, J Q; Ding, M D; Guo, Y; Priest, E R; Parnell, C E; Edwards, S J; Zhang, J; Chen, P F; Fang, C

    2015-01-01T23:59:59.000Z

    Magnetic reconnection, a change of magnetic field connectivity, is a fundamental physical process in which magnetic energy is released explosively. It is responsible for various eruptive phenomena in the universe. However, this process is difficult to observe directly. Here, the magnetic topology associated with a solar reconnection event is studied in three dimensions (3D) using the combined perspectives of two spacecraft. The sequence of extreme ultraviolet (EUV) images clearly shows that two groups of oppositely directed and non-coplanar magnetic loops gradually approach each other, forming a separator or quasi-separator and then reconnecting. The plasma near the reconnection site is subsequently heated from $\\sim$1 to $\\ge$5 MK. Shortly afterwards, warm flare loops ($\\sim$3 MK) appear underneath the hot plasma. Other observational signatures of reconnection, including plasma inflows and downflows, are unambiguously revealed and quantitatively measured. These observations provide direct evidence of magneti...

  7. Cluster beam targets for laser plasma extreme ultraviolet and soft x-ray sources

    DOE Patents [OSTI]

    Kublak, G.D.; Richardson, M.C.

    1996-11-19T23:59:59.000Z

    Method and apparatus for producing extreme ultraviolet (EUV) and soft x-ray radiation from an ultra-low debris plasma source are disclosed. Targets are produced by the free jet expansion of various gases through a temperature controlled nozzle to form molecular clusters. These target clusters are subsequently irradiated with commercially available lasers of moderate intensity (10{sup 11}--10{sup 12} watts/cm{sup 2}) to produce a plasma radiating in the region of 0.5 to 100 nanometers. By appropriate adjustment of the experimental conditions the laser focus can be moved 10--30 mm from the nozzle thereby eliminating debris produced by plasma erosion of the nozzle. 5 figs.

  8. Tabletop Nanometer Extreme Ultraviolet Imaging in an Extended Reflection Mode using Coherent Fresnel Ptychography

    E-Print Network [OSTI]

    Seaberg, Matthew D; Gardner, Dennis F; Shanblatt, Elisabeth R; Murnane, Margaret M; Kapteyn, Henry C; Adams, Daniel E

    2013-01-01T23:59:59.000Z

    We demonstrate high resolution extreme ultraviolet (EUV) coherent diffractive imaging in the most general reflection geometry by combining ptychography with tilted plane correction. This method makes it possible to image extended surfaces at any angle of incidence. Refocused light from a tabletop coherent high harmonic light source at 29 nm illuminates a nanopatterned surface at 45 degree angle of incidence. The reconstructed image contains quantitative amplitude and phase (in this case pattern height) information, comparing favorably with both scanning electron microscope and atomic force microscopy images. In the future, this approach will enable imaging of complex surfaces and nanostructures with sub-10 nm-spatial resolution and fs-temporal resolution, which will impact a broad range of nanoscience and nanotechnology including for direct application in actinic inspection in support of EUV lithography.

  9. Optimization of extreme ultraviolet photons emission and collection in mass-limited laser produced plasmas for lithography application

    E-Print Network [OSTI]

    Harilal, S. S.

    Optimization of extreme ultraviolet photons emission and collection in mass-limited laser produced in DPP or with pre-pulsing in LPP provide wide area for optimization in regards to conversion efficiency and collection as well as calculating photons source location and size. We optimized several parameters of dual

  10. TEMPERATURE AND EXTREME-ULTRAVIOLET INTENSITY IN A CORONAL PROMINENCE CAVITY AND STREAMER

    SciTech Connect (OSTI)

    Kucera, T. A. [NASA/GSFC, Code 671, Greenbelt, MD 20771 (United States); Gibson, S. E.; Schmit, D. J. [HAO/NCAR, P.O. Box 3000, Boulder, CO 80307-3000 (United States); Landi, E. [Department of Atmospheric, Oceanic and Space Science, Space Research Building, University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143 (United States); Tripathi, D. [Inter-University Centre for Astronomy and Astrophysics, Post Bag-4, Ganeshkhind, Pune University Campus, Pune 411 007 (India)

    2012-09-20T23:59:59.000Z

    We analyze the temperature and EUV line emission of a coronal cavity and surrounding streamer in terms of a morphological forward model. We use a series of iron line ratios observed with the Hinode Extreme-ultraviolet Imaging Spectrograph (EIS) on 2007 August 9 to constrain temperature as a function of altitude in a morphological forward model of the streamer and cavity. We also compare model predictions to the EIS EUV line intensities and polarized brightness (pB) data from the Mauna Loa Solar Observatory (MLSO) Mark 4 K-coronameter. This work builds on earlier analysis using the same model to determine geometry of and density in the same cavity and streamer. The fit to the data with altitude-dependent temperature profiles indicates that both the streamer and cavity have temperatures in the range 1.4-1.7 MK. However, the cavity exhibits substantial substructure such that the altitude-dependent temperature profile is not sufficient to completely model conditions in the cavity. Coronal prominence cavities are structured by magnetism so clues to this structure are to be found in their plasma properties. These temperature substructures are likely related to structures in the cavity magnetic field. Furthermore, we find that the model overestimates the EUV line intensities by a factor of 4-10, without overestimating pB. We discuss this difference in terms of filling factors and uncertainties in density diagnostics and elemental abundances.

  11. Hot-electron-driven charge transfer processes on O2 Pt,,111... surface probed by ultrafast extreme-ultraviolet pulses

    E-Print Network [OSTI]

    Bauer, Michael

    it with an ultrafast laser pulse, charge transfer induced changes in the platinum-oxygen bond were observedHot-electron-driven charge transfer processes on O2 Ã?Pt,,111... surface probed by ultrafast extreme-ultraviolet pulses C. Lei,1, * M. Bauer,2 K. Read,1 R. Tobey,1 Y. Liu,3 T. Popmintchev,1 M. M. Murnane,1 and H. C

  12. High-peak-power surface high-harmonic generation at extreme ultra-violet wavelengths from a tape

    SciTech Connect (OSTI)

    Shaw, B. H. [Lawrence Berkeley National Lab, Berkeley, California 94720 (United States) [Lawrence Berkeley National Lab, Berkeley, California 94720 (United States); Applied Science and Technology, University of California, Berkeley, California 94720 (United States); Tilborg, J. van; Sokollik, T.; Schroeder, C. B.; McKinney, W. R.; Artemiev, N. A.; Yashchuk, V. V.; Gullikson, E. M. [Lawrence Berkeley National Lab, Berkeley, California 94720 (United States)] [Lawrence Berkeley National Lab, Berkeley, California 94720 (United States); Leemans, W. P. [Lawrence Berkeley National Lab, Berkeley, California 94720 (United States) [Lawrence Berkeley National Lab, Berkeley, California 94720 (United States); Physics Department, University of California, Berkeley, California 94720 (United States)

    2013-07-28T23:59:59.000Z

    Solid-based surface high-harmonic generation from a tape is experimentally studied. By operating at mildly relativistic normalized laser strengths a{sub 0}?0.2, harmonics up to the 17th order are efficiently produced in the coherent wake emission (CWE) regime. CWE pulse properties, such as divergence, energy, conversion efficiency, and spectrum, are investigated for various tape materials and drive laser conditions. A clear correlation between surface roughness and harmonic beam divergence is found. At the measured pulse properties for the 15th harmonic (conversion efficiency ?6.5×10{sup ?7}, divergence ?7?15 mrad), the 100-mJ-level drive laser produces several MWs of extreme ultra-violet pulses. The spooling tape configuration enables multi-Hz operation over thousands of shots, making this source attractive as a seed to the few-Hz laser-plasma-accelerator-driven free-electron laser (FEL). Models indicate that these CWE pulses with MW level powers are sufficient for seed-induced bunching and FEL gain.

  13. ACTIVE REGION MOSS: DOPPLER SHIFTS FROM HINODE/EXTREME-ULTRAVIOLET IMAGING SPECTROMETER OBSERVATIONS

    SciTech Connect (OSTI)

    Tripathi, Durgesh [Inter-University Centre for Astronomy and Astrophysics, Pune University Campus, Pune 411007 (India); Mason, Helen E. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Klimchuk, James A. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2012-07-01T23:59:59.000Z

    Studying the Doppler shifts and the temperature dependence of Doppler shifts in moss regions can help us understand the heating processes in the core of the active regions. In this paper, we have used an active region observation recorded by the Extreme-ultraviolet Imaging Spectrometer (EIS) on board Hinode on 2007 December 12 to measure the Doppler shifts in the moss regions. We have distinguished the moss regions from the rest of the active region by defining a low-density cutoff as derived by Tripathi et al. in 2010. We have carried out a very careful analysis of the EIS wavelength calibration based on the method described by Young et al. in 2012. For spectral lines having maximum sensitivity between log T = 5.85 and log T = 6.25 K, we find that the velocity distribution peaks at around 0 km s{sup -1} with an estimated error of 4-5 km s{sup -1}. The width of the distribution decreases with temperature. The mean of the distribution shows a blueshift which increases with increasing temperature and the distribution also shows asymmetries toward blueshift. Comparing these results with observables predicted from different coronal heating models, we find that these results are consistent with both steady and impulsive heating scenarios. However, the fact that there are a significant number of pixels showing velocity amplitudes that exceed the uncertainty of 5 km s{sup -1} is suggestive of impulsive heating. Clearly, further observational constraints are needed to distinguish between these two heating scenarios.

  14. An extreme ultraviolet Michelson interferometer for experiments at free-electron lasers

    SciTech Connect (OSTI)

    Hilbert, Vinzenz; Fuchs, Silvio; Paulus, Gerhard G.; Zastrau, Ulf [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany)] [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Blinne, Alexander [Institute for Theoretical Physics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany)] [Institute for Theoretical Physics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Feigl, Torsten [Fraunhofer Institute for Applied Optics and Precision Engineering, Albert-Einstein-Straße 7, 07745 Jena (Germany)] [Fraunhofer Institute for Applied Optics and Precision Engineering, Albert-Einstein-Straße 7, 07745 Jena (Germany); Kämpfer, Tino; Rödel, Christian; Uschmann, Ingo; Wünsche, Martin; Förster, Eckhart [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany) [Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz Institute, Fröbelstieg 3, 07743 Jena (Germany)

    2013-09-15T23:59:59.000Z

    We present a Michelson interferometer for 13.5 nm soft x-ray radiation. It is characterized in a proof-of-principle experiment using synchrotron radiation, where the temporal coherence is measured to be 13 fs. The curvature of the thin-film beam splitter membrane is derived from the observed fringe pattern. The applicability of this Michelson interferometer at intense free-electron lasers is investigated, particularly with respect to radiation damage. This study highlights the potential role of such Michelson interferometers in solid density plasma investigations using, for instance, extreme soft x-ray free-electron lasers. A setup using the Michelson interferometer for pseudo-Nomarski-interferometry is proposed.

  15. Ionization and dissociation dynamics of vinyl bromide probed by femtosecond extreme ultraviolet transient absorption spectroscopy

    SciTech Connect (OSTI)

    Lin, Ming-Fu; Neumark, Daniel M. [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States) [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Chemistry, University of California, Berkeley, California 94720 (United States); Gessner, Oliver [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Leone, Stephen R. [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States) [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Chemistry, University of California, Berkeley, California 94720 (United States); Department of Physics, University of California, Berkeley, California 94720 (United States)

    2014-02-14T23:59:59.000Z

    Strong-field induced ionization and dissociation dynamics of vinyl bromide, CH{sub 2}=CHBr, are probed using femtosecond extreme ultraviolet (XUV) transient absorption spectroscopy. Strong-field ionization is initiated with an intense femtosecond, near infrared (NIR, 775 nm) laser field. Femtosecond XUV pulses covering the photon energy range of 50-72 eV probe the subsequent dynamics by measuring the time-dependent spectroscopic features associated with transitions of the Br (3d) inner-shell electrons to vacancies in molecular and atomic valence orbitals. Spectral signatures are observed for the depletion of neutral C{sub 2}H{sub 3}Br, the formation of C{sub 2}H{sub 3}Br{sup +} ions in their ground (X{sup ~}) and first excited (A{sup ~}) states, the production of C{sub 2}H{sub 3}Br{sup ++} ions, and the appearance of neutral Br ({sup 2}P{sub 3/2}) atoms by dissociative ionization. The formation of free Br ({sup 2}P{sub 3/2}) atoms occurs on a timescale of 330 ± 150 fs. The ionic A{sup ~} state exhibits a time-dependent XUV absorption energy shift of ?0.4 eV within the time window of the atomic Br formation. The yield of Br atoms correlates with the yield of parent ions in the A{sup ~} state as a function of NIR peak intensity. The observations suggest that a fraction of vibrationally excited C{sub 2}H{sub 3}Br{sup +} (A{sup ~}) ions undergoes intramolecular vibrational energy redistribution followed by the C–Br bond dissociation. The C{sub 2}H{sub 3}Br{sup +} (X{sup ~}) products and the majority of the C{sub 2}H{sub 3}Br{sup ++} ions are relatively stable due to a deeper potential well and a high dissociation barrier, respectively. The results offer powerful new insights about orbital-specific electronic processes in high field ionization, coupled vibrational relaxation and dissociation dynamics, and the correlation of valence hole-state location and dissociation in polyatomic molecules, all probed simultaneously by ultrafast table-top XUV spectroscopy.

  16. HINODE/EXTREME-ULTRAVIOLET IMAGING SPECTROMETER OBSERVATIONS OF THE TEMPERATURE STRUCTURE OF THE QUIET CORONA

    SciTech Connect (OSTI)

    Brooks, David H.; Warren, Harry P. [Space Science Division, Code 7673, Naval Research Laboratory, Washington, DC 20375 (United States); Williams, David R. [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT (United Kingdom); Watanabe, Tetsuya, E-mail: dhbrooks@ssd5.nrl.navy.mi [National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2009-11-10T23:59:59.000Z

    We present a differential emission measure (DEM) analysis of the quiet solar corona on disk using data obtained by the Extreme-ultraviolet Imaging Spectrometer (EIS) on Hinode. We show that the expected quiet-Sun DEM distribution can be recovered from judiciously selected lines, and that their average intensities can be reproduced to within 30%. We present a subset of these selected lines spanning the temperature range log T = 5.6-6.4 K that can be used to derive the DEM distribution reliably, including a subset of iron lines that can be used to derive the DEM distribution free of the possibility of uncertainties in the elemental abundances. The subset can be used without the need for extensive measurements, and the observed intensities can be reproduced to within the estimated uncertainty in the pre-launch calibration of EIS. Furthermore, using this subset, we also demonstrate that the quiet coronal DEM distribution can be recovered on size scales down to the spatial resolution of the instrument (1'' pixels). The subset will therefore be useful for studies of small-scale spatial inhomogeneities in the coronal temperature structure, for example, in addition to studies requiring multiple DEM derivations in space or time. We apply the subset to 45 quiet-Sun data sets taken in the period 2007 January to April, and show that although the absolute magnitude of the coronal DEM may scale with the amount of released energy, the shape of the distribution is very similar up to at least log T approx 6.2 K in all cases. This result is consistent with the view that the shape of the quiet-Sun DEM is mainly a function of the radiating and conducting properties of the plasma and is fairly insensitive to the location and rate of energy deposition. This universal DEM may be sensitive to other factors such as loop geometry, flows, and the heating mechanism, but if so they cannot vary significantly from quiet-Sun region to region.

  17. Spatio-temporal coherence of free-electron laser radiation in the extreme ultraviolet determined by a Michelson interferometer

    SciTech Connect (OSTI)

    Hilbert, V.; Rödel, C.; Zastrau, U., E-mail: ulf.zastrau@uni-jena.de [Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena (Germany); Brenner, G.; Düsterer, S.; Dziarzhytski, S.; Harmand, M.; Przystawik, A.; Redlin, H.; Toleikis, S. [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg (Germany); Döppner, T.; Ma, T. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States); Fletcher, L. [Department of Physics, University of California, Berkeley, California 94720 (United States); Förster, E. [Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena (Germany); Glenzer, S. H.; Lee, H. J. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Hartley, N. J. [Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Kazak, L.; Komar, D.; Skruszewicz, S. [Institut für Physik, Universität Rostock, 18051 Rostock (Germany); and others

    2014-09-08T23:59:59.000Z

    A key feature of extreme ultraviolet (XUV) radiation from free-electron lasers (FELs) is its spatial and temporal coherence. We measured the spatio-temporal coherence properties of monochromatized FEL pulses at 13.5?nm using a Michelson interferometer. A temporal coherence time of (59±8) fs has been determined, which is in good agreement with the spectral bandwidth given by the monochromator. Moreover, the spatial coherence in vertical direction amounts to about 15% of the beam diameter and about 12% in horizontal direction. The feasibility of measuring spatio-temporal coherence properties of XUV FEL radiation using interferometric techniques advances machine operation and experimental studies significantly.

  18. Extreme ultraviolet ionization of pure He nanodroplets: Mass-correlated photoelectron imaging, Penning ionization, and electron energy-loss spectra

    SciTech Connect (OSTI)

    Buchta, D.; Stienkemeier, F.; Mudrich, M. [Physikalisches Institut, Universität Freiburg, 79104 Freiburg (Germany)] [Physikalisches Institut, Universität Freiburg, 79104 Freiburg (Germany); Krishnan, S. R.; Moshammer, R. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany)] [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); Brauer, N. B.; Drabbels, M. [Laboratoire de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland)] [Laboratoire de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); O’Keeffe, P.; Coreno, M. [CNR Istituto di Metodologie Inorganiche e dei Plasmi, CP10, 00016 Monterotondo Scalo (Italy)] [CNR Istituto di Metodologie Inorganiche e dei Plasmi, CP10, 00016 Monterotondo Scalo (Italy); Devetta, M. [CIMAINA and Dipartimento di Fisica, Università di Milano, 20133 Milano (Italy)] [CIMAINA and Dipartimento di Fisica, Università di Milano, 20133 Milano (Italy); Di Fraia, M. [Department of Physics, University of Trieste, 34128 Trieste (Italy)] [Department of Physics, University of Trieste, 34128 Trieste (Italy); Callegari, C.; Richter, R.; Prince, K. C. [Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste (Italy)] [Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste (Italy); Ullrich, J. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany) [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, D-38116 Braunschweig (Germany)

    2013-08-28T23:59:59.000Z

    The ionization dynamics of pure He nanodroplets irradiated by Extreme ultraviolet radiation is studied using Velocity-Map Imaging PhotoElectron-PhotoIon COincidence spectroscopy. We present photoelectron energy spectra and angular distributions measured in coincidence with the most abundant ions He{sup +}, He{sub 2}{sup +}, and He{sub 3}{sup +}. Surprisingly, below the autoionization threshold of He droplets, we find indications for multiple excitation and subsequent ionization of the droplets by a Penning-like process. At high photon energies we observe inelastic collisions of photoelectrons with the surrounding He atoms in the droplets.

  19. Time dependent changes in extreme ultraviolet reflectivity of Ru mirrors from electron-induced surface chemistry

    E-Print Network [OSTI]

    Harilal, S. S.

    for Materials Under Extreme Environment, School of Nuclear Engineering Purdue University, West Lafayette verified by Auger electron spectroscopy (AES). Moreover, the impact on EUV reflectivity (EUVR) with time

  20. Method for high-precision multi-layered thin film deposition for deep and extreme ultraviolet mirrors

    DOE Patents [OSTI]

    Ruffner, J.A.

    1999-06-15T23:59:59.000Z

    A method for coating (flat or non-flat) optical substrates with high-reflectivity multi-layer coatings for use at Deep Ultra-Violet (DUV) and Extreme Ultra-Violet (EUV) wavelengths. The method results in a product with minimum feature sizes of less than 0.10 [micro]m for the shortest wavelength (13.4 nm). The present invention employs a computer-based modeling and deposition method to enable lateral and vertical thickness control by scanning the position of the substrate with respect to the sputter target during deposition. The thickness profile of the sputter targets is modeled before deposition and then an appropriate scanning algorithm is implemented to produce any desired, radially-symmetric thickness profile. The present invention offers the ability to predict and achieve a wide range of thickness profiles on flat or figured substrates, i.e., account for 1/R[sup 2] factor in a model, and the ability to predict and accommodate changes in deposition rate as a result of plasma geometry, i.e., over figured substrates. 15 figs.

  1. Method for high-precision multi-layered thin film deposition for deep and extreme ultraviolet mirrors

    DOE Patents [OSTI]

    Ruffner, Judith Alison (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    A method for coating (flat or non-flat) optical substrates with high-reflectivity multi-layer coatings for use at Deep Ultra-Violet ("DUV") and Extreme Ultra-Violet ("EUV") wavelengths. The method results in a product with minimum feature sizes of less than 0.10-.mu.m for the shortest wavelength (13.4-nm). The present invention employs a computer-based modeling and deposition method to enable lateral and vertical thickness control by scanning the position of the substrate with respect to the sputter target during deposition. The thickness profile of the sputter targets is modeled before deposition and then an appropriate scanning algorithm is implemented to produce any desired, radially-symmetric thickness profile. The present invention offers the ability to predict and achieve a wide range of thickness profiles on flat or figured substrates, i.e., account for 1/R.sup.2 factor in a model, and the ability to predict and accommodate changes in deposition rate as a result of plasma geometry, i.e., over figured substrates.

  2. Extended-range grazing-incidence spectrometer for high-resolution extreme ultraviolet measurements on an electron beam ion trap

    SciTech Connect (OSTI)

    Beiersdorfer, P.; Magee, E. W.; Brown, G. V.; Träbert, E.; Widmann, K. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hell, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, 96049 Bamberg (Germany)

    2014-11-15T23:59:59.000Z

    A high-resolution grazing-incidence grating spectrometer has been implemented on the Livermore electron beam ion traps for performing very high-resolution measurements in the soft x-ray and extreme ultraviolet region spanning from below 10 Å to above 300 Å. The instrument operates without an entrance slit and focuses the light emitted by highly charged ions located in the roughly 50 ?m wide electron beam onto a cryogenically cooled back-illuminated charge-coupled device detector. The measured line widths are below 0.025 Å above 100 Å, and the resolving power appears to be limited by the source size and Doppler broadening of the trapped ions. Comparisons with spectra obtained with existing grating spectrometers show an order of magnitude improvement in spectral resolution.

  3. Cold-target recoil-ion momentum spectroscopy for diagnostics of high harmonics of the extreme-ultraviolet free-electron laser light source at SPring-8

    SciTech Connect (OSTI)

    Liu, X.-J.; Fukuzawa, H.; Pruemper, G.; Ueda, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Okunishi, M.; Shimada, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Motomura, K.; Saito, N. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); National Metrology Institute of Japan, AIST, Tsukuba 305-8568 (Japan); Iwayama, H.; Nagaya, K.; Yao, M. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Department of Physics, Kyoto University, Kyoto 606-8502 (Japan); Rudenko, A. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Max Planck Advanced Study Group, CFEL, D-22607, Hamburg (Germany); Ullrich, J. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Max Planck Advanced Study Group, CFEL, D-22607, Hamburg (Germany); Max Planck-Insitut fuer Kernphysik, D-69117 Heidelberg (Germany); Foucar, L. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Czasch, A.; Schmidt-Boecking, H.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Nagasono, M.; Higashiya, A.; Yabashi, M. [RIKEN, XFEL Project Head Office, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); and others

    2009-05-15T23:59:59.000Z

    We have developed a cold-target recoil-ion momentum spectroscopy apparatus dedicated to the experiments using the extreme-ultraviolet light pulses at the free-electron laser facility, SPring-8 Compact SASE Source test accelerator, in Japan and used it to measure spatial distributions of fundamental, second, and third harmonics at the end station.

  4. Investigations into ultraviolet matrix-assisted laser desorption

    SciTech Connect (OSTI)

    Heise, T.W.

    1993-07-01T23:59:59.000Z

    Matrix-assisted laser desorption (MALD) is a technique for converting large biomolecules into gas phase ions. Some characteristics of the commonly used uv matrices are determined. Solubilities in methanol range from 0.1 to 0.5 M. Solid phase absorption spectra are found to be similar to solution, but slightly red-shifted. Acoustic and quartz crystal microbalance signals are investigated as possible means of uv-MALD quantitation. Evidence for the existence of desorption thresholds is presented. Threshold values are determined to be in the range of 2 to 3 MW/cm{sup 2}. A transient imaging technique based on laser-excited fluorescence for monitoring MALD plumes is described. Sensitivity is well within the levels required for studying matrix-assisted laser desorption, where analyte concentrations are significantly lower than those in conventional laser desorption. Results showing the effect of film morphology, particularly film thickness, on plume dynamics are presented. In particular, MALD plumes from thicker films tend to exhibit higher axial velocities. Fluorescent labeling of protein and of DNA is used to allow imaging of their uv-MALD generated plumes. Integrated concentrations are available with respect to time, making it possible to assess the rate of fragmentation. The spatial and temporal distributions are important for the design of secondary ionization schemes to enhance ion yields and for the optimization of ion collection in time-of-flight MS instruments to maximize resolution. Such information could also provide insight into whether ionization is closely associated with the desorption step or whether it is a result of subsequent collisions with the matrix gas (e.g., proton transfer). Although the present study involves plumes in a normal atmosphere, adaptation to measurements in vacuum (e.g., inside a mass spectrometer) should be straightforward.

  5. Cluster beam targets for laser plasma extreme ultraviolet and soft x-ray sources

    DOE Patents [OSTI]

    Kublak, Glenn D. (124 Turquoise Way, Livermore, Alameda County, CA 94550); Richardson, Martin C. (CREOL

    1996-01-01T23:59:59.000Z

    Method and apparatus for producing extreme ultra violet (EUV) and soft x-ray radiation from an ultra-low debris plasma source are disclosed. Targets are produced by the free jet expansion of various gases through a temperature controlled nozzle to form molecular clusters. These target clusters are subsequently irradiated with commercially available lasers of moderate intensity (10.sup.11 -10.sup.12 watts/cm.sup.2) to produce a plasma radiating in the region of 0.5 to 100 nanometers. By appropriate adjustment of the experimental conditions the laser focus can be moved 10-30 mm from the nozzle thereby eliminating debris produced by plasma erosion of the nozzle.

  6. An upper limit on the ratio between the Extreme Ultraviolet and the bolometric luminosities of stars hosting habitable planets

    E-Print Network [OSTI]

    Sengupta, Sujan

    2015-01-01T23:59:59.000Z

    A large number of terrestrial planets in the classical habitable zone of stars of different spectral types has already been discovered and many are expected to be discovered in near future. However, owing to the lack of knowledge on the atmospheric properties, the ambient environment of such planets are unknown. It is known that sufficient amount of Extreme Ultraviolet (EUV) radiation from the star can drive hydrodynamic outflow of hydrogen that may drag heavier species from the atmosphere of the planet. If the rate of mass loss is sufficiently high then substantial amount of volatiles would escape causing the planet to become uninhabitable. Considering energy-limited hydrodynamical mass loss with an escape rate that causes oxygen to escape along with hydrogen, I present an upper limit for the ratio between the EUV and the bolometric luminosities of stars which constrains the habitability of planets around them. Application of the limit to planet-hosting stars with known EUV luminosities implies that many M-t...

  7. DIFFRACTION, REFRACTION, AND REFLECTION OF AN EXTREME-ULTRAVIOLET WAVE OBSERVED DURING ITS INTERACTIONS WITH REMOTE ACTIVE REGIONS

    SciTech Connect (OSTI)

    Shen Yuandeng; Liu Yu; Zhao Ruijuan; Tian Zhanjun [Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China); Su Jiangtao [Key Laboratory of Solar Activity, Chinese Academy of Sciences, Beijing 100012 (China); Li Hui [Key Laboratory of Dark Matter and Space Astronomy, Chinese Academy of Sciences, Nanjing 210008 (China); Ichimoto, Kiyoshi; Shibata, Kazunari, E-mail: ydshen@ynao.ac.cn [Kwasan and Hida Observatories, Kyoto University, Kyoto 6078471 (Japan)

    2013-08-20T23:59:59.000Z

    We present observations of the diffraction, refraction, and reflection of a global extreme-ultraviolet (EUV) wave propagating in the solar corona. These intriguing phenomena are observed when the wave interacts with two remote active regions, and together they exhibit properties of an EUV wave. When the wave approached AR11465, it became weaker and finally disappeared in the active region, but a few minutes later a new wavefront appeared behind the active region, and it was not concentric with the incoming wave. In addition, a reflected wave was also simultaneously observed on the wave incoming side. When the wave approached AR11459, it transmitted through the active region directly and without reflection. The formation of the new wavefront and the transmission could be explained with diffraction and refraction effects, respectively. We propose that the different behaviors observed during the interactions may be caused by different speed gradients at the boundaries of the two active regions. We find that the EUV wave formed ahead of a group of expanding loops a few minutes after the start of the loops' expansion, which represents the initiation of the associated coronal mass ejection (CME). Based on these results, we conclude that the EUV wave should be a nonlinear magnetosonic wave or shock driven by the associated CME, which propagated faster than the ambient fast mode speed and gradually slowed down to an ordinary linear wave. Our observations support the hybrid model that includes both fast wave and slow non-wave components.

  8. BRIGHT POINTS AND JETS IN POLAR CORONAL HOLES OBSERVED BY THE EXTREME-ULTRAVIOLET IMAGING SPECTROMETER ON HINODE

    SciTech Connect (OSTI)

    Doschek, G. A.; Landi, E.; Warren, H. P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Harra, L. K., E-mail: george.doschek@nrl.navy.mi [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom)

    2010-02-20T23:59:59.000Z

    We present observations of polar coronal hole bright points (BPs) made with the Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft. The data consist of raster images of BPs in multiple spectral lines from mostly coronal ions, e.g., Fe X-Fe XV. The BPs are observed for short intervals and thus the data are snapshots of the BPs obtained during their evolution. The images reveal a complex unresolved temperature structure (EIS resolution is about 2''), with the highest temperature being about 2 x 10{sup 6} K. Some BPs appear as small loops with temperatures that are highest near the top. But others are more point-like with surrounding structures. However, the thermal time evolution of the BPs is an important factor in their appearance. A BP may appear quite different at different times. We discuss one BP with an associated jet that is bright enough to allow statistically meaningful measurements. The jet Doppler speed along the line of sight is about 15-20 km s{sup -1}. Electron densities of the BPs and the jet are typically near 10{sup 9} cm{sup -3}, which implies path lengths along the line of sight on the order of a few arcsec. We also construct differential emission measure curves for two of the best observed BPs. High spatial resolution (significantly better than 1'') is required to fully resolve the BP structures.

  9. Absolute intensity calibration of flat-field space-resolved extreme ultraviolet spectrometer using radial profiles of visible and extreme ultraviolet bremsstrahlung continuum emitted from high-density plasmas in Large Helical Device

    SciTech Connect (OSTI)

    Dong Chunfeng; Wang Erhui [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); Morita, Shigeru; Goto, Motoshi [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); National Institute for Fusion Science, Toki 509-5292, Gifu (Japan)

    2011-11-15T23:59:59.000Z

    A precise absolute intensity calibration of a flat-field space-resolved extreme ultraviolet (EUV) spectrometer working in wavelength range of 60-400 A is carried out using a new calibration technique based on radial profile measurement of the bremsstrahlung continuum in Large Helical Device. A peaked vertical profile of the EUV bremsstrahlung continuum has been successfully observed in high-density plasmas (n{sub e}{>=} 10{sup 14} cm{sup -3}) with hydrogen ice pellet injection. The absolute calibration can be done by comparing the EUV bremsstrahlung profile with the visible bremsstrahlung profile of which the absolute value has been already calibrated using a standard lamp. The line-integrated profile of measured visible bremsstrahlung continuum is firstly converted into the local emissivity profile by considering a magnetic surface distortion due to the plasma pressure, and the local emissivity profile of EUV bremsstrahlung is secondly calculated by taking into account the electron temperature profile and free-free gaunt factor. The line-integrated profile of the EUV bremsstrahlung continuum is finally calculated from the local emissivity profile in order to compare with measured EUV bremsstrahlung profile. The absolute intensity calibration can be done by comparing measured and calculated EUV bremsstrahlung profiles. The calibration factor is thus obtained as a function of wavelength with excellent accuracy. It is also found in the profile analysis that the grating reflectivity of EUV emissions is constant along the direction perpendicular to the wavelength dispersion. Uncertainties on the calibration factor determined with the present method are discussed including charge-coupled device operation modes.

  10. Effect of motions in prominences on the helium resonance lines in the extreme ultraviolet

    E-Print Network [OSTI]

    Nicolas Labrosse; Pierre Gouttebroze; Jean-Claude Vial

    2006-12-08T23:59:59.000Z

    We aim at studying the effect of radial motions on the spectrum emitted by moving prominences in the helium resonance lines and at facilitating the interpretation of observations, in order to improve our understanding of these dynamic structures. We develop our non-local thermodynamic equilibrium radiative transfer code formerly used for the study of quiescent prominences. The new numerical code is now able to solve the statistical equilibrium and radiative transfer equations in the non-static case by using velocity-dependent boundary conditions for the solution of the radiative transfer problem. This first study investigates the effects of different physical conditions (temperature, pressure, geometrical thickness) on the emergent helium radiation. The motion of the prominence plasma induces a Doppler dimming effect on the resonance lines of He I and He II. The velocity effects are particularly important for the He II 304 A line as it is mostly formed by resonant diffusion of incident radiation under prominence conditions. The He I resonance lines at 584 and 537 A also show some sensitivity to the motion of the plasma, all the more when thermal emission is not too important in these lines. We also show that it is necessary to consider partial redistribution in frequency for the scattering of the incident radiation. This set of helium lines offers strong diagnostic possibilities that can be exploited with the SOHO spectrometers and with the EIS spectrometer on board the Hinode satellite. The addition of other helium lines and of lines from other elements (in particular hydrogen) in the diagnostics will further enhance the strength of the method.

  11. Development of extreme ultraviolet and soft x-ray multilayer optics for scientific studies with femtosecond/attosecond sources

    SciTech Connect (OSTI)

    Aquila, Andrew Lee

    2009-05-21T23:59:59.000Z

    The development of multilayer optics for extreme ultraviolet (EUV) radiation has led to advancements in many areas of science and technology, including materials studies, EUV lithography, water window microscopy, plasma imaging, and orbiting solar physics imaging. Recent developments in femtosecond and attosecond EUV pulse generation from sources such as high harmonic generation lasers, combined with the elemental and chemical specificity provided by EUV radiation, are opening new opportunities to study fundamental dynamic processes in materials. Critical to these efforts is the design and fabrication of multilayer optics to transport, focus, shape and image these ultra-fast pulses This thesis describes the design, fabrication, characterization, and application of multilayer optics for EUV femtosecond and attosecond scientific studies. Multilayer mirrors for bandwidth control, pulse shaping and compression, tri-material multilayers, and multilayers for polarization control are described. Characterization of multilayer optics, including measurement of material optical constants, reflectivity of multilayer mirrors, and metrology of reflected phases of the multilayer, which is critical to maintaining pulse size and shape, were performed. Two applications of these multilayer mirrors are detailed in the thesis. In the first application, broad bandwidth multilayers were used to characterize and measure sub-100 attosecond pulses from a high harmonic generation source and was performed in collaboration with the Max-Planck institute for Quantum Optics and Ludwig- Maximilians University in Garching, Germany, with Professors Krausz and Kleineberg. In the second application, multilayer mirrors with polarization control are useful to study femtosecond spin dynamics in an ongoing collaboration with the T-REX group of Professor Parmigiani at Elettra in Trieste, Italy. As new ultrafast x-ray sources become available, for example free electron lasers, the multilayer designs described in this thesis can be extended to higher photon energies, and such designs can be used with those sources to enable new scientific studies, such as molecular bonding, phonon, and spin dynamics.

  12. Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source

    SciTech Connect (OSTI)

    Barkusky, Frank; Bayer, Armin; Peth, Christian; Mann, Klaus [Laser-Laboratorium-Goettingen e.V., Hans-Adolf-Krebs-Weg 1, D-37077 Goettingen (Germany)

    2009-01-01T23:59:59.000Z

    In order to perform material interaction studies with intense extreme ultraviolet (EUV) radiation, a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10x demagnified imaging of the plasma a maximum pulse energy density of {approx}0.73 J/cm{sup 2} at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate, polycarbonate, and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data, etch rates were determined, revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore, the surface roughness of the structured polymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface, indicating a rather smooth etch process (roughness increase of 20%-30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates, having consequences for the proper use of polymer ablation for beam profiling of focused EUV radiation.

  13. Extreme ultraviolet reflector

    DOE Patents [OSTI]

    Newnam, Brian E. (Los Alamos, NM)

    1990-01-01T23:59:59.000Z

    A multi-faceted mirror forms a retroreflector for a resonator loop in a free electron laser (FEL) operating in the XUV (.lambda.=10-100 nm). The number of facets is determined by the angle-of-incidence needed to obtain total external reflectance (TER) from the facet surface and the angle through which the FEL beam is to be turned. Angles-of-incidence greater than the angle for TER may be used to increase the area of the beam incident on the surface and reduce energy absorption density. Suitable surface films having TER in the 10-100 nm range may be formed from a variety of materials, including Al, single-crystal Si, Ag, and Rh. One of the facets is formed as an off-axis conic section to collimate the output beam with minimum astigmatism.

  14. CHROMOSPHERIC EVAPORATION IN AN M1.8 FLARE OBSERVED BY THE EXTREME-ULTRAVIOLET IMAGING SPECTROMETER ON HINODE

    SciTech Connect (OSTI)

    Doschek, G. A.; Warren, H. P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)] [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Young, P. R. [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)] [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)

    2013-04-10T23:59:59.000Z

    We discuss observations of chromospheric evaporation for a complex flare that occurred on 2012 March 9 near 03:30 UT obtained from the Extreme-ultraviolet Imaging Spectrometer (EIS) on board the Hinode spacecraft. This was a multiple event with a strong energy input that reached the M1.8 class when observed by EIS. EIS was in raster mode and fortunately the slit was almost at the exact location of a significant energy input. Also, EIS obtained a full-CCD spectrum of the flare, i.e., the entire CCD was readout so that data were obtained for about the 500 lines identified in the EIS wavelength ranges. Chromospheric evaporation characterized by 150-200 km s{sup -1} upflows was observed in multiple locations in multi-million degree spectral lines of flare ions such as Fe XXII, Fe XXIII, and Fe XXIV, with simultaneous 20-60 km s{sup -1} upflows in million degree coronal lines from ions such as Fe XII-Fe XVI. The behavior of cooler, transition region ions such as O VI, Fe VIII, He II, and Fe X is more complex, but upflows were also observed in Fe VIII and Fe X lines. At a point close to strong energy input in space and time, the flare ions Fe XXII, Fe XXIII, and Fe XXIV reveal an isothermal source with a temperature close to 14 MK and no strong blueshifted components. At this location there is a strong downflow in cooler active region lines from ions such as Fe XIII and Fe XIV, on the order of 200 km s{sup -1}. We speculate that this downflow may be evidence of the downward shock produced by reconnection in the current sheet seen in MHD simulations. A sunquake also occurred near this location. Electron densities were obtained from density sensitive lines ratios from Fe XIII and Fe XIV. Atmospheric Imaging Assembly (AIA) observations from the Solar Dynamics Observatory are used with JHelioviewer to obtain a qualitative overview of the flare. However, AIA data are not presented in this paper. In summary, spectroscopic data from EIS are presented that can be used for predictive tests of models of chromospheric evaporation as envisaged in the Standard Flare Model.

  15. Study of extreme-ultraviolet emission and properties of a coronal streamer from PROBA2/SWAP, HINODE/EIS and Mauna Loa Mk4 observations

    SciTech Connect (OSTI)

    Goryaev, F.; Slemzin, V.; Vainshtein, L. [P.N. Lebedev Physical Institute of the RAS (LPI), Moscow 119991 (Russian Federation); Williams, David R., E-mail: goryaev_farid@mail.ru [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Surrey, RH5 6NT (United Kingdom)

    2014-02-01T23:59:59.000Z

    Wide-field extreme-ultraviolet (EUV) telescopes imaging in spectral bands sensitive to 1 MK plasma on the Sun often observe extended, ray-like coronal structures stretching radially from active regions to distances of 1.5-2 R {sub ?}, which represent the EUV counterparts of white-light streamers. To explain this phenomenon, we investigated the properties of a streamer observed on 2010 October 20 and 21, by the PROBA2/SWAP EUV telescope together with the Hinode/EIS (HOP 165) and the Mauna Loa Mk4 white-light coronagraph. In the SWAP 174 Å band comprising the Fe IX-Fe XI lines, the streamer was detected to a distance of 2 R {sub ?}. We assume that the EUV emission is dominated by collisional excitation and resonant scattering of monochromatic radiation coming from the underlying corona. Below 1.2 R {sub ?}, the plasma density and temperature were derived from the Hinode/EIS data by a line-ratio method. Plasma conditions in the streamer and in the background corona above 1.2 R {sub ?} from the disk center were determined by forward-modeling the emission that best fit the observational data in both EUV and white light. It was found that the plasma in the streamer above 1.2 R {sub ?} is nearly isothermal, with a temperature of T = 1.43 ± 0.08 MK. The hydrostatic scale-height temperature determined from the evaluated density distribution was significantly higher (1.72 ± 0.08 MK), which suggests the existence of outward plasma flow along the streamer. We conclude that, inside the streamer, collisional excitation provided more than 90% of the observed EUV emission, whereas, in the background corona, the contribution of resonance scattering became comparable with that of collisions at R ? 2 R {sub ?}.

  16. EVIDENCE FOR THE WAVE NATURE OF AN EXTREME ULTRAVIOLET WAVE OBSERVED BY THE ATMOSPHERIC IMAGING ASSEMBLY ON BOARD THE SOLAR DYNAMICS OBSERVATORY

    SciTech Connect (OSTI)

    Shen Yuandeng; Liu Yu, E-mail: ydshen@ynao.ac.cn [Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China)

    2012-07-20T23:59:59.000Z

    Extreme-ultraviolet (EUV) waves have been found for about 15 years. However, significant controversy remains over their physical natures and origins. In this paper, we report an EUV wave that was accompanied by an X1.9 flare and a partial halo coronal mass ejection (CME). Using high temporal and spatial resolution observations taken by the Solar Dynamics Observatory and the Solar-TErrestrial RElations Observatory, we are able to investigate the detailed kinematics of the EUV wave. We find several arguments that support the fast-mode wave scenario. (1) The speed of the EUV wave (570 km s{sup -1}) is higher than the sound speed of the quiet-Sun corona. (2) Significant deceleration of the EUV wave (-130 m s{sup -2}) is found during its propagation. (3) The EUV wave resulted in the oscillations of a loop and a filament along its propagation path, and a reflected wave from the polar coronal hole is also detected. (4) Refraction or reflection effect is observed when the EUV wave was passing through two coronal bright points. (5) The dimming region behind the wavefront stopped to expand when the wavefront started to become diffuse. (6) The profiles of the wavefront exhibited a dispersive nature, and the magnetosonic Mach number of the EUV wave derived from the highest intensity jump is about 1.4. In addition, triangulation indicates that the EUV wave propagated within a height range of about 60-100 Mm above the photosphere. We propose that the EUV wave observed should be a nonlinear fast-mode magnetosonic wave that propagated freely in the corona after it was driven by the CME expanding flanks during the initial period.

  17. Generation of circularly polarized radiation from a compact plasma-based extreme ultraviolet light source for tabletop X-ray magnetic circular dichroism studies

    SciTech Connect (OSTI)

    Wilson, Daniel; Rudolf, Denis, E-mail: d.rudolf@fz-juelich.de; Juschkin, Larissa [RWTH Aachen University, Experimental Physics of EUV, Steinbachstraße 15, 52074 Aachen (Germany); Forschungszentrum Jülich GmbH, Peter Grünberg Institut (PGI-9), JARA-FIT, 52425 Jülich (Germany); Weier, Christian; Adam, Roman; Schneider, Claus M. [Forschungszentrum Jülich GmbH, Peter Grünberg Institut (PGI-6), JARA-FIT, 52425 Jülich (Germany); Winkler, Gerrit; Frömter, Robert [Institut für Angewandte Physik, Universität Hamburg, Jungiusstraße 11, 20355 Hamburg (Germany); Danylyuk, Serhiy [RWTH Aachen University, Chair for Technology of Optical Systems, JARA-FIT, Steinbachstraße 15, 52074 Aachen (Germany); Bergmann, Klaus [Fraunhofer Institute for Laser Technology, Steinbachstrasse 15, 52074 Aachen (Germany); Grützmacher, Detlev [Forschungszentrum Jülich GmbH, Peter Grünberg Institut (PGI-9), JARA-FIT, 52425 Jülich (Germany)

    2014-10-15T23:59:59.000Z

    Generation of circularly polarized light in the extreme ultraviolet (EUV) spectral region (about 25 eV–250 eV) is highly desirable for applications in spectroscopy and microscopy but very challenging to achieve in a small-scale laboratory. We present a compact apparatus for generation of linearly and circularly polarized EUV radiation from a gas-discharge plasma light source between 50 eV and 70 eV photon energy. In this spectral range, the 3p absorption edges of Fe (54 eV), Co (60 eV), and Ni (67 eV) offer a high magnetic contrast often employed for magneto-optical and electron spectroscopy as well as for magnetic imaging. We simulated and designed an instrument for generation of linearly and circularly polarized EUV radiation and performed polarimetric measurements of the degree of linear and circular polarization. Furthermore, we demonstrate first measurements of the X-ray magnetic circular dichroism at the Co 3p absorption edge with a plasma-based EUV light source. Our approach opens the door for laboratory-based, element-selective spectroscopy of magnetic materials and spectro-microscopy of ferromagnetic domains.

  18. A portable high-resolution soft x-ray and extreme ultraviolet spectrometer designed for the Shanghai EBIT and the Shanghai low energy EBITs

    SciTech Connect (OSTI)

    Shi, Zhan; Zhao, Ruifeng; Li, Wenxian; Tu, Bingsheng; Yang, Yang, E-mail: yangyang@fudan.edu.cn; Xiao, Jun; Hutton, Roger; Zou, Yaming [EBIT Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); The Key Laboratory of Applied Ion Beam Physics (Ministry of Education), Fudan University, Shanghai 200433 (China); Huldt, Sven [Lund Observatory, Lund University, Lund SE-22100 (Sweden)

    2014-06-15T23:59:59.000Z

    A portable high resolution soft x-ray and extreme ultraviolet (EUV) spectrometer has been developed for spectroscopic research at the Shanghai Electron Beam Ion Trap (EBIT) laboratory. A unique way of aligning the grazing incidence spectrometer using the zero order of the grating is introduced. This method is realized by extending the range of the movement of the CCD detector to cover the zero order. The alignment can be done in a few minutes, thus leading to a portable spectrometer. The high vacuum needed to be compatible with the EBITs is reached by mounting most of the translation and rotation stages outside the chamber. Only one high vacuum compatible linear guide is mounted inside the chamber. This is to ensure the convenient interchange of the gratings needed to enable wavelength coverage of the whole range of 10 to 500 Å. Spectra recorded with one of our low energy EBITs shows that a resolving power of above 800 can be achieved. In the slitless configuration used in this work, we found the resolving power to be limited by the width of the EBIT plasma. When mounted on the Shanghai EBIT which is a high energy EBIT and has a narrower EBIT plasma width, the estimated resolving power will be around 1400 at 221.15 Å.

  19. FAST EXTREME-ULTRAVIOLET DIMMING ASSOCIATED WITH A CORONAL JET SEEN IN MULTI-WAVELENGTH AND STEREOSCOPIC OBSERVATIONS

    SciTech Connect (OSTI)

    Lee, K.-S.; Moon, Y.-J.; Lee, Jin-Yi [Department of Astronomy and Space Science, Kyung Hee University, Yongin 446-701 (Korea, Republic of)] [Department of Astronomy and Space Science, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Innes, D. E. [Max Plank Institute for Solar System Research, D-37191 Katlenburg-Lindau (Germany)] [Max Plank Institute for Solar System Research, D-37191 Katlenburg-Lindau (Germany); Shibata, K. [Kwasan and Hida Observatories, Kyoto University, Yamashina, Kyoto 607-8471 (Japan)] [Kwasan and Hida Observatories, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Park, Y.-D., E-mail: lksun@khu.ac.kr [Solar and Space Weather Research Group, Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of)

    2013-03-20T23:59:59.000Z

    We have investigated a coronal jet observed near the limb on 2010 June 27 by the Hinode/X-Ray Telescope (XRT), EUV Imaging Spectrograph (EIS), and Solar Optical Telescope (SOT), and by the Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA), and on the disk by STEREO-A/EUVI. From EUV (AIA and EIS) and soft X-ray (XRT) images we have identified both cool and hot jets. There was a small loop eruption seen in Ca II images of the SOT before the jet eruption. We found that the hot jet preceded its associated cool jet by about 2 minutes. The cool jet showed helical-like structures during the rising period which was supported by the spectroscopic analysis of the jet's emission. The STEREO observation, which enabled us to observe the jet projected against the disk, showed dimming at 195 A along a large loop connected to the jet. We measured a propagation speed of {approx}800 km s{sup -1} for the dimming front. This is comparable to the Alfven speed in the loop computed from a magnetic field extrapolation of the photospheric field measured five days earlier by the SDO/Helioseismic and Magnetic Imager, and the loop densities obtained from EIS Fe XIV {lambda}264.79/274.20 line ratios. We interpret the dimming as indicating the presence of Alfvenic waves initiated by reconnection in the upper chromosphere.

  20. Extreme Ultraviolet Light Chris Cosio

    E-Print Network [OSTI]

    Hart, Gus

    polycarbonate disk to separate the plasma chamber from the current source. Polycarbonate is problematic due

  1. Investigating the effective range of vacuum ultraviolet-mediated breakdown in high-power microwave metamaterials

    SciTech Connect (OSTI)

    Liu, Chien-Hao, E-mail: cliu82@wisc.edu; Neher, Joel D., E-mail: jdneher@wisc.edu; Booske, John H., E-mail: booske@engr.wisc.edu; Behdad, Nader, E-mail: behdad@wisc.edu [Department of Electrical and Computer Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, Wisconsin 53706 (United States)

    2014-10-14T23:59:59.000Z

    Metamaterials and periodic structures operating under high-power excitations are susceptible to breakdown. It was recently demonstrated that a localized breakdown created in a given region of a periodic structure can facilitate breakdown in other regions of the structure where the intensity of the incident electromagnetic fields may not be high enough to cause breakdown under normal circumstances. It was also demonstrated that this phenomenon is due to the generation of vacuum ultraviolet radiation at the location of the initial discharge, which propagates to the neighboring regions (e.g., other unit cells in a periodic structure) and facilitates the generation of a discharge at a lower incident power level. In this paper, we present the results of an experimental study conducted to determine the effective range of this physical phenomenon for periodic structures that operate in air and in pure nitrogen gas at atmospheric pressure levels. It is demonstrated that when breakdown is induced in a periodic structure using a high-power pulse with a frequency of 9.382 GHz, duration of 0.8 ?s, and peak power level of 25 kW, this phenomenon is highly likely to happen in radii of approximately 16–17 mm from the location of the initial discharge under these test conditions. The results of this study are significant in designing metamaterials and periodic structures for high-power microwave applications as they suggest that a localized discharge created in such a periodic structure with a periodicity less than 16–17 mm can spread over a large surface and result in a distributed discharge.

  2. Space-resolved extreme ultraviolet spectroscopy free of high-energy neutral particle noise in wavelength range of 10–130 Å on the large helical device

    SciTech Connect (OSTI)

    Huang, Xianli, E-mail: huang.xianli@nifs.ac.jp [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan)] [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan); Morita, Shigeru; Oishi, Tetsutarou; Goto, Motoshi [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan) [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan); National Institute for Fusion Science, Toki 509-5292 Gifu (Japan); Dong, Chunfeng [Southwestern Institute of Physics, P.O. Box 432, Chengdu, Sichuan 610041 (China)] [Southwestern Institute of Physics, P.O. Box 432, Chengdu, Sichuan 610041 (China)

    2014-04-15T23:59:59.000Z

    A flat-field space-resolved extreme ultraviolet (EUV) spectrometer system working in wavelength range of 10–130 Å has been constructed in the Large Helical Device (LHD) for profile measurements of bremsstrahlung continuum and line emissions of heavy impurities in the central column of plasmas, which are aimed at studies on Z{sub eff} and impurity transport, respectively. Until now, a large amount of spike noise caused by neutral particles with high energies (?180 keV) originating in neutral beam injection has been observed in EUV spectroscopy on LHD. The new system has been developed with an aim to delete such a spike noise from the signal by installing a thin filter which can block the high-energy neutral particles entering the EUV spectrometer. Three filters of 11 ?m thick beryllium (Be), 3.3 ?m thick polypropylene (PP), and 0.5 ?m thick polyethylene terephthalate (PET: polyester) have been examined to eliminate the spike noise. Although the 11 ?m Be and 3.3 ?m PP filters can fully delete the spike noise in wavelength range of ? ? 20 Å, the signal intensity is also reduced. The 0.5 ?m PET filter, on the other hand, can maintain sufficient signal intensity for the measurement and the spike noise remained in the signal is acceptable. As a result, the bremsstrahlung profile is successfully measured without noise at 20 Å even in low-density discharges, e.g., 2.9 × 10{sup 13} cm{sup ?3}, when the 0.5 ?m PET filter is used. The iron n = 3–2 L? transition array consisting of FeXVII to FeXXIV is also excellently observed with their radial profiles in wavelength range of 10–18 Å. Each transition in the L? array can be accurately identified with its radial profile. As a typical example of the method a spectral line at 17.62 Å is identified as FeXVIII transition. Results on absolute intensity calibration of the spectrometer system, pulse height and noise count analyses of the spike noise between holographic and ruled gratings and wavelength response of the used filters are also presented with performance of the present spectrometer system.

  3. SECONDARY WAVES AND/OR THE 'REFLECTION' FROM AND 'TRANSMISSION' THROUGH A CORONAL HOLE OF AN EXTREME ULTRAVIOLET WAVE ASSOCIATED WITH THE 2011 FEBRUARY 15 X2.2 FLARE OBSERVED WITH SDO/AIA AND STEREO/EUVI

    SciTech Connect (OSTI)

    Olmedo, Oscar; Vourlidas, Angelos [Space Science Division, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Zhang Jie [School of Physics, Astronomy and Computational Sciences, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Cheng Xin, E-mail: oscar.olmedo.ctr@nrl.navy.mil [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)

    2012-09-10T23:59:59.000Z

    For the first time, the kinematic evolution of a coronal wave over the entire solar surface is studied. Full Sun maps can be made by combining images from the Solar Terrestrial Relations Observatory satellites, Ahead and Behind, and the Solar Dynamics Observatory, thanks to the wide angular separation between them. We study the propagation of a coronal wave, also known as the 'Extreme Ultraviolet Imaging Telescope' wave, and its interaction with a coronal hole (CH) resulting in secondary waves and/or reflection and transmission. We explore the possibility of the wave obeying the law of reflection. In a detailed example, we find that a loop arcade at the CH boundary cascades and oscillates as a result of the extreme ultraviolet (EUV) wave passage and triggers a wave directed eastward that appears to have reflected. We find that the speed of this wave decelerates to an asymptotic value, which is less than half of the primary EUV wave speed. Thanks to the full Sun coverage we are able to determine that part of the primary wave is transmitted through the CH. This is the first observation of its kind. The kinematic measurements of the reflected and transmitted wave tracks are consistent with a fast-mode magnetohydrodynamic wave interpretation. Eventually, all wave tracks decelerate and disappear at a distance. A possible scenario of the whole process is that the wave is initially driven by the expanding coronal mass ejection and subsequently decouples from the driver and then propagates at the local fast-mode speed.

  4. Multiple pulse thermal damage thresholds of materials for x-ray free electron laser optics investigated with an ultraviolet laser

    SciTech Connect (OSTI)

    Hau-Riege, Stefan P.; London, Richard A.; Bionta, Richard M.; Soufli, Regina; Ryutov, Dmitri; Shirk, Michael; Baker, Sherry L. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94539 (United States); Smith, Patrick M.; Nataraj, Pradeep [Kovio, Inc., 1145 Sonora Court, Sunnyvale, California 94086 (United States)

    2008-11-17T23:59:59.000Z

    Optical elements to be used for x-ray free electron lasers (XFELs) must withstand multiple high-fluence pulses. We have used an ultraviolet laser to study the damage of two candidate materials, crystalline Si and B{sub 4}C-coated Si, emulating the temperature profile expected to occur in optics exposed to XFEL pulses. We found that the damage threshold for 10{sup 5} pulses is {approx}20% to 70% lower than the melting threshold.

  5. Investigating Operating System Noise in Extreme-Scale High-Performance Computing Systems using Simulation

    SciTech Connect (OSTI)

    Engelmann, Christian [ORNL

    2013-01-01T23:59:59.000Z

    Hardware/software co-design for future-generation high-performance computing (HPC) systems aims at closing the gap between the peak capabilities of the hardware and the performance realized by applications (application-architecture performance gap). Performance profiling of architectures and applications is a crucial part of this iterative process. The work in this paper focuses on operating system (OS) noise as an additional factor to be considered for co-design. It represents the first step in including OS noise in HPC hardware/software co-design by adding a noise injection feature to an existing simulation-based co-design toolkit. It reuses an existing abstraction for OS noise with frequency (periodic recurrence) and period (duration of each occurrence) to enhance the processor model of the Extreme-scale Simulator (xSim) with synchronized and random OS noise simulation. The results demonstrate this capability by evaluating the impact of OS noise on MPI_Bcast() and MPI_Reduce() in a simulated future-generation HPC system with 2,097,152 compute nodes.

  6. The Extreme Ultraviolet and X-Ray Sun in Time: High-Energy Evolutionary Tracks of a Solar-Like Star

    E-Print Network [OSTI]

    Tu, Lin; Güdel, Manuel; Lammer, Helmut

    2015-01-01T23:59:59.000Z

    Aims. We aim to describe the pre-main sequence and main-sequence evolution of X-ray and extreme-ultaviolet radiation of a solar mass star based on its rotational evolution starting with a realistic range of initial rotation rates. Methods. We derive evolutionary tracks of X-ray radiation based on a rotational evolution model for solar mass stars and the rotation-activity relation. We compare these tracks to X-ray luminosity distributions of stars in clusters with different ages. Results. We find agreement between the evolutionary tracks derived from rotation and the X-ray luminosity distributions from observations. Depending on the initial rotation rate, a star might remain at the X-ray saturation level for very different time periods, approximately from 10 Myr to 300 Myr for slow and fast rotators, respectively. Conclusions. Rotational evolution with a spread of initial conditions leads to a particularly wide distribution of possible X-ray luminosities in the age range of 20 to 500 Myrs, before rotational co...

  7. A plasmon enhanced attosecond extreme ultraviolet source

    E-Print Network [OSTI]

    Mattia Lupetti; Matthias F. Kling; Armin Scrinzi

    2012-11-24T23:59:59.000Z

    A compact high repetition rate attosecond light source based on a standard laser oscillator combined with plasmonic enhancement is presented. At repetition rates of tens of MHz, we predict focusable pulses with durations of ~< 300 attoseconds, and collimation angles ~< 5 degrees. Attosecond pulse parameters are robust with respect variations of driver pulse focus and duration.

  8. Extreme Ultraviolet Spectroscopy of the Solar Corona

    E-Print Network [OSTI]

    Del Zanna, Giulio

    range of spectroscopic diagnostic tech- niques to determine the temperature distribution, densities a factor of 2 lower than in the quiet sun, with much lower emission measures at temperatures above 106 K been used to infer the temperature structure and the element abundances. The importance of including

  9. Ultraviolet imaging of hydrogen flames

    SciTech Connect (OSTI)

    Yates, G.J.; Wilke, M.; King, N.

    1988-01-01T23:59:59.000Z

    We have assembled an ultraviolet-sensitive intensified camera for observing hydrogen combustion by imaging the OH, A/sup 2/..sigma.. - X/sup 2//Pi/ bandhead emissions near 309 nm. The camera consists of a quartz and CaF achromat lense-coupled to an ultraviolet image intensifier which is in turn fiber-coupled to a focus projection scan (FPS) vidicon. The emission band is selected with interference filters which serve to discriminate against background. The camera provides optical gain of 100 to 1000 and is capable of being shuttered at nanosecond speeds and of being framed at over 600 frames per second. We present data from observations of test flames in air at standard RS-170 video rates with varying background conditions. Enhanced images using background subtraction are presented. Finally, we discuss the use of polarizaton effects to further discrimination against sky background. This work began as a feasibility study to investigate ultraviolet technology to detect hydrogen fires for the NASA space program. 6 refs., 7 figs, 2 tabs.

  10. all-solid-state ultraviolet laser: Topics by E-print Network

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

    C. S. Menoni, and J. J. Rocca NSFERC for Extreme Ultraviolet Science. J. E. Trebes, S. B. Brown, E. M. Campbell, D. L. Matthews, D. G. Nilson, G. F. Stone, and D. A amplifier,"...

  11. Ultraviolet stimulation of hydrogen peroxide production using...

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

    Ultraviolet stimulation of hydrogen peroxide production using aminoindazole, diaminopyridine, and phenylenediamine solid polymer Ultraviolet stimulation of hydrogen peroxide...

  12. Volume extreme ultraviolet holographic imaging with numerical optical sectioning

    E-Print Network [OSTI]

    Rocca, Jorge J.

    .2960) Image analysis References and Links 1. J. E. Trebes, S. B. Brown, E. M. Campbell, D. L. Matthews, D. G. Nilson, G. F. Stone, and D. A. Whelan, "Demonstration of X-Ray holography with an X-Ray laser," Science, 1788-1800 (1996). 3. I. McNulty, J. Kirz, C. Jacobsen, E. Anderson, M. R. Howells, and D. P. Kern

  13. Corner Rounding in Photoresists for Extreme Ultraviolet Lithography

    SciTech Connect (OSTI)

    Anderson, Christopher N.; Naulleau, Patrick; Deng, Yunfei; Wallow, Thomas

    2008-06-01T23:59:59.000Z

    Deprotection blur in EUV resists fundamentally limits the smallest sized dense features that can be patterned in a single exposure and development step. Several metrics have recently been developed to explore the ways that different resist and process parameters affect the deprotection blur in EUV resists. One of these metrics is based on the imaging fidelity of a sharp corner on a large feature. As this metric has involved the close inspection of printing fidelity of corner features, it has brought attention to an interesting phenomena: corners print differently whether or not the remaining resist edge contains 270 degrees of resist or 90 degrees of resist. Here we present experimental data across a wide sampling of leading resists to show this effect is real and reproducible. They provide aerial image modeling results assuming thin and realistic mask models that show no corner bias between the aerial images in the 90-degree and 270-degree configurations. They also compare modeled patterning results assuming several resist models including the single blur, dual blur, and Prolith models, none of which reproduce the corner biasing that is observed experimentally.

  14. Erosion resistant nozzles for laser plasma extreme ultraviolet (EUV) sources

    DOE Patents [OSTI]

    Kubiak, Glenn D. (Livermore, CA); Bernardez, II, Luis J. (Tracy, CA)

    2000-01-04T23:59:59.000Z

    A gas nozzle having an increased resistance to erosion from energetic plasma particles generated by laser plasma sources. By reducing the area of the plasma-facing portion of the nozzle below a critical dimension and fabricating the nozzle from a material that has a high EUV transmission as well as a low sputtering coefficient such as Be, C, or Si, it has been shown that a significant reduction in reflectance loss of nearby optical components can be achieved even after exposing the nozzle to at least 10.sup.7 Xe plasma pulses.

  15. PROMINENCE PLASMA DIAGNOSTICS THROUGH EXTREME-ULTRAVIOLET ABSORPTION

    SciTech Connect (OSTI)

    Landi, E. [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Reale, F. [Dipartimento di Fisica e Chimica, Universita di Palermo, Piazza del Parlamento 1, I-90134 Palermo (Italy)

    2013-07-20T23:59:59.000Z

    In this paper, we introduce a new diagnostic technique that uses EUV and UV absorption to determine the electron temperature and column emission measure, as well as the He/H relative abundance of the absorbing plasma. If a realistic assumption on the geometry of the latter can be made and a spectral code such as CHIANTI is used, then this technique can also yield the absorbing plasma hydrogen and electron density. This technique capitalizes on the absorption properties of hydrogen and helium at different wavelength ranges and temperature regimes. Several cases where this technique can be successfully applied are described. This technique works best when the absorbing plasma is hotter than 15,000 K. We demonstrate this technique on AIA observations of plasma absorption during a coronal mass ejection eruption. This technique can be easily applied to existing observations of prominences and cold plasmas in the Sun from almost all space missions devoted to the study of the solar atmosphere, which we list.

  16. Ultrafast Extreme Ultraviolet Induced Isomerization of Acetylene Cations

    E-Print Network [OSTI]

    Jiang, Y.

    2012-01-01T23:59:59.000Z

    PHYSICAL REVIEW LETTERS PRL 105, 263002 (2010) week endingAmerican Physical Society PRL 105, 263002 (2010) PHYSICALcould not be distinguished. PRL 105, 263002 (2010) PHYSICAL

  17. Ultraviolet | Jefferson Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |FrankUltrafastHydrogen andPortalUltraviolet

  18. Mineralogy under extreme conditions

    SciTech Connect (OSTI)

    Shu, Jinfu (CIW)

    2012-02-07T23:59:59.000Z

    We have performed measurements of minerals based on the synchrotron source for single crystal and powder X-ray diffraction, inelastic scattering, spectroscopy and radiography by using diamond anvil cells. We investigated the properties of iron (Fe), iron-magnesium oxides (Fe, Mg)O, silica(SiO{sub 2}), iron-magnesium silicates (Fe, Mg)SiO{sub 3} under simulated high pressure-high temperature extreme conditions of the Earth's crust, upper mantle, low mantle, core-mantle boundary, outer core, and inner core. The results provide a new window on the investigation of the mineral properties at Earth's conditions.

  19. Type B Accident Investigation Board Report on the June 2002 High Radiation Dose to Extremities in Building 151, Lawrence Livermore National Laboratory

    Broader source: Energy.gov [DOE]

    This report is an independent product of the Type B Accident Investigation Board appointed by Camille Yuan-Soo Hoo, Manager of the U.S. Department of Energy, Oakland Operations Office.

  20. Diffractive element in extreme-UV lithography condenser

    DOE Patents [OSTI]

    Sweatt, William C. (Albuquerque, NM); Ray-Chaudhurl, Avijit K. (Livermore, CA)

    2000-01-01T23:59:59.000Z

    Condensers having a mirror with a diffraction grating in projection lithography using extreme ultra-violet significantly enhances critical dimension control. The diffraction grating has the effect of smoothing the illumination at the camera's entrance pupil with minimum light loss. Modeling suggests that critical dimension control for 100 nm features can be improved from 3 nm to less than about 0.5 nm.

  1. Diffractive element in extreme-UV lithography condenser

    DOE Patents [OSTI]

    Sweatt, William C. (Albuquerque, NM); Ray-Chaudhuri, Avijit (Livermore, CA)

    2001-01-01T23:59:59.000Z

    Condensers having a mirror with a diffraction grating in projection lithography using extreme ultra-violet significantly enhances critical dimension control. The diffraction grating has the effect of smoothing the illumination at the camera's entrance pupil with minimum light loss. Modeling suggests that critical dimension control for 100 nm features can be improved from 3 nm to less than about 0.5 nm.

  2. The irradiation hardness of CdTe solar cells was inves-tigated for extremely high fluence of protons (up to

    E-Print Network [OSTI]

    Romeo, Alessandro

    by introduction of defects. Investigations of polycrystalline thin film cells like CuInSe2 (CIS), Cu(In,Ga)Se2 radiation stability, superior to monocrys- talline cells and also slightly superior to other thin film cells of high effi- ciency monocrystalline Si and III-V cells. The stability against particle irradiation

  3. The effects of cerium doping on the size, morphology, and optical properties of ?-hematite nanoparticles for ultraviolet filtration

    SciTech Connect (OSTI)

    Cardillo, Dean [Institute for Superconducting and Electronic Materials, AIIM Facility, University of Wollongong Innovation Campus, Squires Way, North Wollongong, NSW 2500 (Australia); Konstantinov, Konstantin, E-mail: konstan@uow.edu.au [Institute for Superconducting and Electronic Materials, AIIM Facility, University of Wollongong Innovation Campus, Squires Way, North Wollongong, NSW 2500 (Australia); Devers, Thierry [Centre de Recherche sur la Matière Divisée, Institut de Physique, site de Chartres, Université d’Orléans (France)

    2013-11-15T23:59:59.000Z

    Highlights: • Possible application of cerium-doped ?-hematite as ultraviolet filter. • Nanoparticles obtained through co-precipitation technique using various cerium doping levels followed by annealing. • Comprehensive materials characterisation utilizing XRD, DSC/TGA, STEM, UV–vis spectroscopy. • Increasing cerium content reduces particle sizing and alters morphology. • Solubility of cerium in hematite seen between 5 and 10% doping, 10% cerium doping greatly enhances attenuation in ultraviolet region and increases optical bandgap. - Abstract: Metal oxide nanoparticles have potential use in energy storage, electrode materials, as catalysts and in the emerging field of nanomedicine. Being able to accurately tailor the desirable properties of these nanoceramic materials, such as particle size, morphology and optical bandgap (E{sub g}) is integral in the feasibility of their use. In this study we investigate the altering of both the structure and physical properties through the doping of hematite (?-Fe{sub 2}O{sub 3}) nanocrystals with cerium at a range of concentrations, synthesised using a one-pot co-precipitation method. This extremely simple synthesis followed by thermal treatment results in stable Fe{sub 2?x}Ce{sub x}O{sub y} nanoceramics resulting from the burning of any unreacted precursors and transformation of goethite-cerium doped nanoparticle intermediate. The inclusion of Ce into the crystal lattice of these ?-Fe{sub 2}O{sub 3} nanoparticles causes a significantly large reduction in mean crystalline size and alteration in particle morphology with increasing cerium content. Finally we report an increase optical semiconductor bandgap, along with a substantial increase in the ultraviolet attenuation found for a 10% Ce-doping concentration which shows the potential application of cerium-doped hematite nanocrystals to be used as a pigmented ultraviolet filter for cosmetic products.

  4. Nanowire Ultraviolet Photodetectors and Optical By Hannes Kind, Haoquan Yan, Benjamin Messer,

    E-Print Network [OSTI]

    Yang, Peidong

    of a Nd:YAG laser was used as the UV light source. Neutral density filters were used to change the incident UV light power. It was found that the photoresponse (Ipc) can be expressed by a simple power law is extremely sensitive to ultraviolet light exposure. The light-induced conductivity increase allows us

  5. Single-crystalline aluminum film for ultraviolet plasmonic nanolasers

    E-Print Network [OSTI]

    Chou, Bo-Tsun; Wu, Yen-Mo; Chung, Yi-Chen; Hsueh, Wei-Jen; Lin, Shih-Wei; Lu, Tien-Chang; Lin, Tzy-Rong; Lin, Sheng-Di

    2015-01-01T23:59:59.000Z

    Plasmonic devices have advanced significantly in the past decade. Being one of the most intriguing devices, plamonic nanolasers plays an important role in biomedicine, chemical sensor, information technology, and optical integrated circuits. However, nanoscale plasmonic devices, particularly in ultraviolet regime, are extremely sensitive to metal and interface quality, which renders the development of ultraviolet plasmonics. Here, by addressing the material issues, we demonstrate a low threshold, high characteristic temperature metal-oxide-semiconductor ZnO nanolaser working at room temperature. The template for ZnO nanowires consists of a flat single-crystalline aluminum film grown by molecular beam epitaxy and an ultra-smooth Al2O3 spacer layer prepared by atomic layer deposition. By effectively reducing surface plasmon scattering loss and metal intrinsic absorption loss, the high-quality metal film and sharp interfaces between layers boost the device performance. Our work paves the way for future applicati...

  6. Ultraviolet-radiation-curable paints

    SciTech Connect (OSTI)

    Grosset, A M; Su, W F.A.; Vanderglas, E

    1981-09-30T23:59:59.000Z

    In product finishing lines, ultraviolet radiation curing of paints on prefabricated structures could be more energy efficient than curing by natural gas fired ovens, and could eliminate solvent emission. Diffuse ultraviolet light can cure paints on three dimensional metal parts. In the uv curing process, the spectral output of radiation sources must complement the absorption spectra of pigments and photoactive agents. Photosensitive compounds, such as thioxanthones, can photoinitiate unsaturated resins, such as acrylated polyurethanes, by a free radical mechanism. Newly developed cationic photoinitiators, such as sulfonium or iodonium salts (the so-called onium salts) of complex metal halide anions, can be used in polymerization of epoxy paints by ultraviolet light radiation. One-coat enamels, topcoats, and primers have been developed which can be photoinitiated to produce hard, adherent films. This process has been tested in a laboratory scale unit by spray coating these materials on three-dimensional objects and passing them through a tunnel containing uv lamps.

  7. Extremal index estimation 

    E-Print Network [OSTI]

    Kampa, Aleksander Edward

    1988-01-01T23:59:59.000Z

    ) December 1988 Extremal Index Estimation (December 1988) Aleksander Edward Kampa, Ecole Centrale de Paris, France Chairman of Advisory Comittee: Dr. Tailen Hsing If (X ) is a strictly stationary sequence satisfying certain n dependence restrictions (e.... g. D or A), then the relationship between the extremal properties of (X ) and its associated independent sequence (X ) n n can. under certain conditions, be summed up by a single constant Be[0. 1]. called the extremal index. Results of extreme...

  8. Measurement and analysis of near ultraviolet solar radiation

    SciTech Connect (OSTI)

    Mehos, M.S.; Pacheco, K.A.; Link, H.F.

    1991-12-01T23:59:59.000Z

    The photocatalytic detoxification of organic contaminants is currently being investigated by a number of laboratories, universities, and institutions throughout the world. The photocatalytic oxidation process requires that contaminants come in contact with a photocatalyst such as titanium dioxide, under illumination of ultraviolet (UV) radiation in order for the decomposition reaction to take place. Researches from the National Renewable Energy Laboratory (NREL) and Sandia National Laboratories are currently investigating the use of solar energy as a means of driving this photocatalytic process. Measurements of direct-normal and global-horizontal ultraviolet (280--385 nm) and full-spectrum (280--4000 nm) solar radiation taken in Golden, Colorado over a one-year period are analyzed, and comparisons are made with data generated from a clear-sky solar radiation model (BRITE) currently in use for predicting the performance of solar detoxification processes. Analysis of the data indicates a ratio of global-horizontal ultraviolet to full-spectrum radiation of 4%--6% that is weakly dependent on air mass. Conversely, data for direct-normal ultraviolet radiation indicate a much large dependence on air mass, with a ratio of approximately 5% at low air mass to 1% at higher at masses. Results show excellent agreement between the measured data and clear-sky predictions for both the ultraviolet and the full-spectrum global-horizontal radiation. For the direct-normal components, however, the tendency is for the clear-sky model to underpredict the measured that. Averaged monthly ultraviolet radiation available for the detoxification process indicates that the global-horizontal component of the radiation exceeds the direct-normal component throughout the year. 9 refs., 7 figs.

  9. Wafer chamber having a gas curtain for extreme-UV lithography

    DOE Patents [OSTI]

    Kanouff, Michael P. (Livermore, CA); Ray-Chaudhuri, Avijit K. (Livermore, CA)

    2001-01-01T23:59:59.000Z

    An EUVL device includes a wafer chamber that is separated from the upstream optics by a barrier having an aperture that is permeable to the inert gas. Maintaining an inert gas curtain in the proximity of a wafer positioned in a chamber of an extreme ultraviolet lithography device can effectively prevent contaminants from reaching the optics in an extreme ultraviolet photolithography device even though solid window filters are not employed between the source of reflected radiation, e.g., the camera, and the wafer. The inert gas removes the contaminants by entrainment.

  10. The dangers of extremes

    E-Print Network [OSTI]

    Donald Marolf

    2010-05-17T23:59:59.000Z

    While extreme black hole spacetimes with smooth horizons are known at the level of mathematics, we argue that the horizons of physical extreme black holes are effectively singular. Test particles encounter a singularity the moment they cross the horizon, and only objects with significant back-reaction can fall across a smooth (now non-extreme) horizon. As a result, classical interior solutions for extreme black holes are theoretical fictions that need not be reproduced by any quantum mechanical model. This observation suggests that significant quantum effects might be visible outside extreme or nearly extreme black holes. It also suggests that the microphysics of such black holes may be very different from that of their Schwarzschild cousins.

  11. Extremely Large EUV Late Phase of Solar Flares

    E-Print Network [OSTI]

    Liu, Kai; Zhang, Jie; Cheng, Xin; Liu, Rui; Shen, Chenglong

    2015-01-01T23:59:59.000Z

    The second peak in the Fe XVI 33.5 nm line irradiance observed during solar flares by Extreme ultraviolet Variability Experiment (EVE) is known as Extreme UltraViolet (EUV) late phase. Our previous paper (Liu et al. 2013) found that the main emissions in the late phase are originated from large-scale loop arcades that are closely connected to but different from the post flare loops (PFLs), and we also proposed that a long cooling process without additional heating could explain the late phase. In this paper, we define the extremely large late phase because it not only has a bigger peak in the warm 33.5 irradiance profile, but also releases more EUV radiative energy than the main phase. Through detailedly inspecting the EUV images from three point-of-view, it is found that, besides the later phase loop arcades, the more contribution of the extremely large late phase is from a hot structure that fails to erupt. This hot structure is identified as a flux rope, which is quickly energized by the flare reconnection...

  12. Extreme-UV electrical discharge source

    DOE Patents [OSTI]

    Fornaciari, Neal R. (Tracey, CA); Nygren, Richard E. (Los Ranchos de Albuquerque, NM); Ulrickson, Michael A. (Albuquerque, NM)

    2002-01-01T23:59:59.000Z

    An extreme ultraviolet and soft x-ray radiation electric capillary discharge source that includes a boron nitride housing defining a capillary bore that is positioned between two electrodes one of which is connected to a source of electric potential can generate a high EUV and soft x-ray radiation flux from the capillary bore outlet with minimal debris. The electrode that is positioned adjacent the capillary bore outlet is typically grounded. Pyrolytic boron nitride, highly oriented pyrolytic boron nitride, and cubic boron nitride are particularly suited. The boron nitride capillary bore can be configured as an insert that is encased in an exterior housing that is constructed of a thermally conductive material. Positioning the ground electrode sufficiently close to the capillary bore outlet also reduces bore erosion.

  13. DETERMINING OPTICAL CONSTANTS OF URANIUM NITRIDE THIN FILMS IN THE EXTREME

    E-Print Network [OSTI]

    Hart, Gus

    DETERMINING OPTICAL CONSTANTS OF URANIUM NITRIDE THIN FILMS IN THE EXTREME ULTRAVIOLET (1.6-35 NM deposition and characterization of reactively-sputtered uranium nitride thin films. I also report optical.1 Application 1 1.2 Optical Constants 2 1.3 Project Focus 7 2 Uranium Nitride Thin Films 8 2.1 Sputtering 8 2

  14. Ultraviolet divergences and supersymmetric theories

    SciTech Connect (OSTI)

    Sagnotti, A.

    1984-09-01T23:59:59.000Z

    This article is closely related to the one by Ferrara in these same Proceedings. It deals with what is perhaps the most fascinating property of supersymmetric theories, their improved ultraviolet behavior. My aim here is to present a survey of the state of the art as of August, 1984, and a somewhat more detailed discussion of the breakdown of the superspace power-counting beyond N = 2 superfields. A method is also described for simplifying divergence calculations that uses the locality of subtracted Feynman integrals. 74 references.

  15. Microgap ultra-violet detector

    DOE Patents [OSTI]

    Wuest, C.R.; Bionta, R.M.

    1994-09-20T23:59:59.000Z

    A microgap ultra-violet detector of photons with wavelengths less than 400 run (4,000 Angstroms) which comprises an anode and a cathode separated by a gas-filled gap and having an electric field placed across the gap is disclosed. Either the anode or the cathode is semi-transparent to UV light. Upon a UV photon striking the cathode an electron is expelled and accelerated across the gap by the electric field causing interactions with other electrons to create an electron avalanche which contacts the anode. The electron avalanche is detected and converted to an output pulse. 2 figs.

  16. A Combined Vacuum Ultraviolet Laser and Synchrotron Pulsed Field...

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

    Vacuum Ultraviolet Laser and Synchrotron Pulsed Field Ionization Study of BCl. A Combined Vacuum Ultraviolet Laser and Synchrotron Pulsed Field Ionization Study of BCl. Abstract:...

  17. Extremal covariant measurements

    E-Print Network [OSTI]

    G. Chiribella; G. M. D'Ariano

    2006-03-20T23:59:59.000Z

    We characterize the extremal points of the convex set of quantum measurements that are covariant under a finite-dimensional projective representation of a compact group, with action of the group on the measurement probability space which is generally non-transitive. In this case the POVM density is made of multiple orbits of positive operators, and, in the case of extremal measurements, we provide a bound for the number of orbits and for the rank of POVM elements. Two relevant applications are considered, concerning state discrimination with mutually unbiased bases and the maximization of the mutual information.

  18. Onsite Wastewater Treatment Systems: Ultraviolet Light Disinfection

    E-Print Network [OSTI]

    Lesikar, Bruce J.

    2008-10-02T23:59:59.000Z

    Some onsite wastewater treatment systems include a disinfection component. This publication explains how homeowners can disinfect wastewater with ultraviolet light, what the components of such a system are, what factors affect the performance of a...

  19. The Local Interstellar Ultraviolet Radiation Field

    E-Print Network [OSTI]

    Richard Conn Henry

    2002-01-03T23:59:59.000Z

    I have used the Hipparcos Input Catalog, together with Kurucz model stellar atmospheres, and information on the strength of the interstellar extinction, to create a model of the expected intensity and spectral distribution of the local interstellar ultraviolet radiation field, under various assumptions concerning the albedo a of the interstellar grains. (This ultraviolet radiation field is of particular interest because of the fact that ultraviolet radiation is capable of profoundly affecting the chemistry of the interstellar medium.) By comparing my models with the observations, I am able to conclude that the albedo a of the interstellar grains in the far ultraviolet is very low, perhaps a = 0.1. I also advance arguments that my present determination of this albedo is much more reliable than any of the many previous (and conflicting) ultraviolet interstellar grain albedo determinations. Beyond this, I show that the ultraviolet background radiation that is observed at high galactic latitudes must be extragalactic in origin, as it cannot be backscatter of the interstellar radiation field.

  20. Extreme Cosmic String

    E-Print Network [OSTI]

    P. F. Gonzalez-Diaz

    1995-08-28T23:59:59.000Z

    This paper deals with the geometry of supermassive cosmic strings. We have used an approach that enforces the spacetime of cosmic strings to also satisfy the conservation laws of a cylindric gravitational topological defect, that is a spacetime kink. In the simplest case of kink number unity, the entire energy range of supermassive strings becomes then quantized so that only cylindrical defects with linear energy density $G\\mu=1/4$ (critical string) and $G\\mu=1/2$ (extreme string) are allowed to occur in this range. It has been seen that the internal spherical coordinate $\\theta$ of the string metric embedded in an Euclidean three-space also evolves on imaginary values, leading to the creation of a covering shell of broken phase that protects the core with trapped energy, even for $G\\mu=1/2$. Then the conical singularity becomes a removable horizaon singularity. We re-express the extreme string metric in the Finkelstein- McCollum standard form and remove the geodesic incompleteness by using the Kruskal technique. The z=const. sections of the resulting metric are the same as the hemispherical section of the metric of a De Sitter kink. Some physical consequences from these results, including the possibility that the extreme string drives inflation and thermal effects in its core, are also discussed.

  1. Vacuum-Ultraviolet (VUV) Photoionization of Small Methanol and Methanol-Water Clusters

    E-Print Network [OSTI]

    Kostko, Oleg

    2008-01-01T23:59:59.000Z

    Vacuum-ultraviolet (VUV) photoionization of small methanolwe report on the vacuum-ultraviolet (VUV) photoionization ofionization with tunable vacuum- ultraviolet synchrotron

  2. Vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters

    E-Print Network [OSTI]

    Ahmed, Musahid

    2008-01-01T23:59:59.000Z

    Physical Chemistry Vacuum-ultraviolet (VUV) photoionizationPhysical Chemistry Vacuum-ultraviolet (VUV) photoionizationwe report on the vacuum-ultraviolet (VUV) photoionization of

  3. QCD in Extreme Environments

    E-Print Network [OSTI]

    John B. Kogut

    2002-08-30T23:59:59.000Z

    I review present challenges that QCD in extreme environments presents to lattice gauge theory. Recent data and impressions from RHIC are emphasized. Physical pictures of heavy ion wavefunctions, collisions and the generation of the Quark Gluon Plasma are discussed, with an eye toward engaging the lattice and its numerical methods in more interaction with the experimental and phenomenological developments. Controversial, but stimulating scenarios which can be confirmed or dismissed by lattice methods are covered. In the second half of the talk, several promising developments presented at the conference Lattice 2002 are reviewed.

  4. Extreme Environments (EFree) Center

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental Assessments (EA) /EmailMolecularGE, Ford,Extracting theExtreme

  5. Precipitation extremes under climate change

    E-Print Network [OSTI]

    O'Gorman, Paul A

    2015-01-01T23:59:59.000Z

    The response of precipitation extremes to climate change is considered using results from theory, modeling, and observations, with a focus on the physical factors that control the response. Observations and simulations with climate models show that precipitation extremes intensify in response to a warming climate. However, the sensitivity of precipitation extremes to warming remains uncertain when convection is important, and it may be higher in the tropics than the extratropics. Several physical contributions govern the response of precipitation extremes. The thermodynamic contribution is robust and well understood, but theoretical understanding of the microphysical and dynamical contributions is still being developed. Orographic precipitation extremes and snowfall extremes respond differently from other precipitation extremes and require particular attention. Outstanding research challenges include the influence of mesoscale convective organization, the dependence on the duration considered, and the need to...

  6. Detection of magnetic dipole lines of Fe XII in the ultraviolet spectrum of the dwarf star Epsilon Eri

    E-Print Network [OSTI]

    C. Jordan; A. D. McMurry; S. A. Sim; M. Arulvel

    2001-01-17T23:59:59.000Z

    We report observations of the dwarf star Epsilon Eri (K2 V) made with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST). The high sensitivity of the STIS instrument has allowed us to detect the magnetic dipole transitions of Fe XII at 1242.00A and 1349.38A for the first time in a star other than the Sun. The width of the stronger line at 1242.00A has also been measured; such measurements are not possible for the permitted lines of Fe XII in the extreme ultraviolet. To within the accurcy of the measurements, the N V and the Fe XII lines occur at their rest wavelengths. Electron densities and line widths have been measured from other transition region lines. Together, these can be used to investigate the non-thermal energy flux in the lower and upper transition region, which is useful in constraining possible heating processes. The Fe XII lines are also present in archival STIS spectra of other G/K-type dwarfs.

  7. The Extreme Physics Explorer

    E-Print Network [OSTI]

    Martin Elvis

    2006-08-25T23:59:59.000Z

    Some tests of fundamental physics - the equation of state at supra-nuclear densities, the metric in strong gravity, the effect of magnetic fields above the quantum critical value - can only be measured using compact astrophysical objects: neutron stars and black holes. The Extreme Physics Explorer is a modest sized (~500 kg) mission that would carry a high resolution (R ~300) X-ray spectrometer and a sensitive X-ray polarimeter, both with high time resolution (~5 ?s) capability, at the focus of a large area (~5 sq.m), low resolution (HPD~1 arcmin) X-ray mirror. This instrumentation would enable new classes of tests of fundamental physics using neutron stars and black holes as cosmic laboratories.

  8. Ultraviolet Limit of Open String Theory

    E-Print Network [OSTI]

    Shyamoli Chaudhuri

    2005-01-21T23:59:59.000Z

    We confirm the intuition that a string theory which is perturbatively infrared finite is automatically perturbatively ultraviolet finite. Our derivation based on the asymptotics of the Selberg trace formula for the Greens function on a Riemann surface holds for both open and closed string amplitudes and is independent of modular invariance and supersymmetry. The mass scale for the open strings stretched between Dbranes suggests a natural world-sheet ultraviolet regulator in the string path integral, preserving both T-duality and open-closed string world-sheet duality. Note added (Jan 2005): Comments and related references added.

  9. The Application of Ultraviolet Germicidal Technology in HVAC Systems

    E-Print Network [OSTI]

    Taylor, M. J.

    2000-01-01T23:59:59.000Z

    capability, which increases the operating costs of the equipment. Fortunately, IAQ degradation, foul odor, and increased expenses can be eliminated with the installation of the ultraviolet 'C' band (W-C) lamps. The ultraviolet germicidal lamps are designed...

  10. Tabletop coherent diffractive microscopy with extreme ultraviolet light from high harmonic generation

    E-Print Network [OSTI]

    Miao, Jianwei "John"

    magnetic and electric properties of variable sized magnetite nano-hollow spheres J. Appl. Phys. 112, 064318

  11. Sub 400 nm spatial resolution extreme ultraviolet holography with a table top laser

    E-Print Network [OSTI]

    Rocca, Jorge J.

    . J. E. Trebes, S. B. Brown, E. M. Campbell, D. L. Matthews, D. G. Nilson, G. F. Stone, and D. A Society of America OCIS codes: (090.0090) Holography; (100.2960) Image analysis References and Links 1. D, C. Jacobsen, E. Anderson, M. R. Howells, and D. P. Kern, "High resolution imaging by Fourier

  12. Extreme-ultraviolet radiation transport in small scale length laser-produced tin plasmas

    E-Print Network [OSTI]

    Sequoia, Kevin Lamar Williams

    2009-01-01T23:59:59.000Z

    Physics) by Kevin Lamar Williams Sequoia Committee inR. Tynan Copyright Kevin Lamar Williams Sequoia, 2009 AllDissertation of Kevin Lamar Williams Sequoia is approved,

  13. Hollow laser self-confined plasma for extreme ultraviolet lithography and other applications

    E-Print Network [OSTI]

    Harilal, S. S.

    that the EUV efficiency of the proposed hollow-beam LPP device to be higher than the current standard devices the microlithography progress. The litho- graphic process generates a semiconductor wafer partially covered

  14. Ultrafast Strong-Field Vibrational Dynamics Studied by Femtosecond Extreme-Ultraviolet Transient Absorption Spectroscopy

    E-Print Network [OSTI]

    Hosler, Erik Robert

    2013-01-01T23:59:59.000Z

    to yield a compressed, ultrafast pulse close to the originalspectral width of the ultrafast optical pulses, delivering

  15. Extreme-ultraviolet radiation transport in small scale length laser-produced tin plasmas

    E-Print Network [OSTI]

    Sequoia, Kevin Lamar Williams

    2009-01-01T23:59:59.000Z

    radiation heated sio2 aerogel plasma in "dog-bone" targetsspectra from Ti-doped aerogels. Journal of Quantitative

  16. High-Order Harmonic Generation Yielding Tunable Extreme-Ultraviolet Radiation of High Spectral Purity

    E-Print Network [OSTI]

    harmonic photon. The universal cutoff in high-order har- monic generation (HHG) processes exists at Ip 3 (ponderomotive) energy of a quasifree electron quivering in the laser field in the neighborhood of the ionic core [9] and for resonance-enhanced wave mixing [10]. In contrast to these studies, in the nonperturbative

  17. High-frequency surface acoustic wave propagation in nanaostructures characterized by coherent extreme ultraviolet beams

    E-Print Network [OSTI]

    Siemens, M.

    2009-01-01T23:59:59.000Z

    8] R. I. Tobey, M. E. Siemens, O. Cohen, M. M. Murnane, H.32(3):286–288, 2007. [9] M. Siemens, Q. Li, M. Murnane, H.2] R. I. Tobey, M. E. Siemens, M. M. Murnane, H. C. Kapteyn,

  18. Enhancing extreme ultraviolet photons emission in laser produced plasmas for advanced lithography

    E-Print Network [OSTI]

    Harilal, S. S.

    subjected to laser beam energy with different intensities and laser wavelength to dual-beam lasers, i of vapor expansion rate, which can be produced as a result of droplet heating by pre-pulse laser energy, and the remaining part of the laser heats the plasma instead of inter- acting with the target. For obtaining

  19. POINT-SPREAD FUNCTIONS FOR THE EXTREME-ULTRAVIOLET CHANNELS OF SDO/AIA TELESCOPES

    SciTech Connect (OSTI)

    Poduval, B.; DeForest, C. E. [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States); Schmelz, J. T.; Pathak, S., E-mail: bala@boulder.swri.edu [Physics Department, University of Memphis, Memphis, TN 38152 (United States)

    2013-03-10T23:59:59.000Z

    We present the stray-light point-spread functions (PSFs) and their inverses we characterized for the Atmospheric Imaging Assembly (AIA) EUV telescopes on board the Solar Dynamics Observatory (SDO) spacecraft. The inverse kernels are approximate inverses under convolution. Convolving the original Level 1 images with them produces images with improved stray-light characteristics. We demonstrate the usefulness of these PSFs by applying them to two specific cases: photometry and differential emission measure (DEM) analysis. The PSFs consist of a narrow Gaussian core, a diffraction component, and a diffuse component represented by the sum of a Gaussian-truncated Lorentzian and a shoulder Gaussian. We determined the diffraction term using the measured geometry of the diffraction pattern identified in flare images and the theoretically computed intensities of the principal maxima of the first few diffraction orders. To determine the diffuse component, we fitted its parameterized model using iterative forward-modeling of the lunar interior in the SDO/AIA images from the 2011 March 4 lunar transit. We find that deconvolution significantly improves the contrast in dark features such as miniature coronal holes, though the effect was marginal in bright features. On a percentage-scattering basis, the PSFs for SDO/AIA are better by a factor of two than that of the EUV telescope on board the Transition Region And Coronal Explorer mission. A preliminary analysis suggests that deconvolution alone does not affect DEM analysis of small coronal loop segments with suitable background subtraction. We include the derived PSFs and their inverses as supplementary digital materials.

  20. Ultrafast Strong-Field Vibrational Dynamics Studied by Femtosecond Extreme-Ultraviolet Transient Absorption Spectroscopy

    E-Print Network [OSTI]

    Hosler, Erik Robert

    2013-01-01T23:59:59.000Z

    Letters 329, 469 A. Rudenko, T. Ergler, B. Feuerstein, K.Ergler, B. Feuerstein, A. Rudenko, K. Zrost, C. D. Schroter,

  1. Ultrafast Strong-Field Vibrational Dynamics Studied by Femtosecond Extreme-Ultraviolet Transient Absorption Spectroscopy

    E-Print Network [OSTI]

    Hosler, Erik Robert

    2013-01-01T23:59:59.000Z

    dynamics. Tunnel ionization rate determinations are employed to model the pump, while electronic structure calculations

  2. Ultrafast Strong-Field Vibrational Dynamics Studied by Femtosecond Extreme-Ultraviolet Transient Absorption Spectroscopy

    E-Print Network [OSTI]

    Hosler, Erik Robert

    2013-01-01T23:59:59.000Z

    in construction, a CO 2 laser drilling platform designed by111 In addition to the laser drilling of the gas inlets, theas well as in the laser drilling of the fiber gas inlets

  3. Time-resolved visible and extreme ultraviolet spectroscopy of laser-produced tin plasma

    E-Print Network [OSTI]

    O'Shay, Joseph Fred

    2007-01-01T23:59:59.000Z

    Characterization of laser-produced tin plasma. Part I: XUVof laser-produced tin plasma. Part II: Radiation-expanding laser-produced tin plasma,” Eighth International

  4. Extreme-ultraviolet radiation transport in small scale length laser-produced tin plasmas

    E-Print Network [OSTI]

    Sequoia, Kevin Lamar Williams

    2009-01-01T23:59:59.000Z

    emissions from laser-produced tin plasmas. Proceedings ofRadiation from Laser- Produced Tin Plasmas. Physical Reviewspectra of xenon and tin discharges. Physical Review E,

  5. CLOSE ASSOCIATION OF AN EXTREME-ULTRAVIOLET SUNSPOT PLUME WITH DEPRESSIONS IN THE SUNSPOT RADIO EMISSION

    E-Print Network [OSTI]

    White, Stephen

    a plume in the sunspot umbra on both observing dates. The plume appears brightest in emission lines formed at temperatures between 1:6 Ã? 105 and 5:0 Ã? 105 K. Radio emission from the sunspot umbra is dominated by thermal gyroemission from the plume, which accounts for radio brightness temperatures umbra on both

  6. Nanometer-scale ablation using focused, coherent extreme ultraviolet/soft x-ray light

    DOE Patents [OSTI]

    Menoni, Carmen S. (Fort Collins, CO); Rocca, Jorge J. (Fort Collins, CO); Vaschenko, Georgiy (San Diego, CA); Bloom, Scott (Encinitas, CA); Anderson, Erik H. (El Cerrito, CA); Chao, Weilun (El Cerrito, CA); Hemberg, Oscar (Stockholm, SE)

    2011-04-26T23:59:59.000Z

    Ablation of holes having diameters as small as 82 nm and having clean walls was obtained in a poly(methyl methacrylate) on a silicon substrate by focusing pulses from a Ne-like Ar, 46.9 nm wavelength, capillary-discharge laser using a freestanding Fresnel zone plate diffracting into third order is described. Spectroscopic analysis of light from the ablation has also been performed. These results demonstrate the use of focused coherent EUV/SXR light for the direct nanoscale patterning of materials.

  7. Characterization of multilayer coated concave diffraction gratings in the extreme ultraviolet

    SciTech Connect (OSTI)

    Bixler, J.; Barbee, T. Jr.; Dietrich, D.

    1989-02-01T23:59:59.000Z

    We describe here our work to date on characterizing two multilayer coated concave diffraction gratings, one conventionally ruled, the other holographically ruled. We have obtained photographic spectra with both gratings which indicate good resolution properties and promising efficiencies. 5 refs., 3 figs.

  8. Extreme-ultraviolet radiation transport in small scale length laser-produced tin plasmas

    E-Print Network [OSTI]

    Sequoia, Kevin Lamar Williams

    2009-01-01T23:59:59.000Z

    a planar target causes a “bowtie” in the mesh near the edgethe same space. When a bowtie occurs in h2d, the problemis in a planar geometry a bowtie will occur before the laser

  9. High resolution coherent diffractive imaging with a table-top extreme ultraviolet source

    SciTech Connect (OSTI)

    Vu Le, Hoang, E-mail: vuhoangle@swin.edu.au; Ba Dinh, Khuong; Hannaford, Peter; Van Dao, Lap [Centre for Quantum and Optical Science, Swinburne University of Technology, Melbourne 3122 (Australia)

    2014-11-07T23:59:59.000Z

    We demonstrate a resolution of 45?nm with a sample size down to 3??m × 3??m is achieved in a short exposure time of 2?s, from the diffraction pattern generated by a table-top high harmonic source at around 30?nm. By using a narrow-bandwidth focusing mirror, the diffraction pattern's quality is improved and the required exposure time is significantly reduced. In order to obtain a high quality of the reconstructed image, the ratio of the beam size to the sample size and the curvature of the focused beam need to be considered in the reconstruction process. This new experimental scheme is very promising for imaging sub-10?nm scale objects with a table-top source based on a small inexpensive femtosecond laser system.

  10. Combined effects of prepulsing and target geometry on efficient extreme ultraviolet

    E-Print Network [OSTI]

    Harilal, S. S.

    and the deposition of EUV and out of band radiation can fur- ther cause surface erosion and damage at the required targets geometries with special grooves as developed previously by the authors. C 2011 Society of Photo-Optical. Damage of multilayer Mo/Si mirrors by the de- bris products of laser beam interaction with target

  11. Sparkling extreme-ultraviolet bright dots observed with Hi-C

    SciTech Connect (OSTI)

    Régnier, S.; Alexander, C. E.; Walsh, R. W. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston, Lancashire, PR1 2HE (United Kingdom); Winebarger, A. R.; Cirtain, J. [NASA Marshall Space Flight Center, VP 62, Huntsville, AL 35812 (United States); Golub, L.; Korreck, K. E.; Weber, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Mitchell, N.; Platt, S. [School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Preston, Lancashire, PR1 2HE (United Kingdom); De Pontieu, B.; Title, A. [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street, Palo Alto, CA 94304 (United States); Kobayashi, K. [Center for Space Plasma and Aeronomic Research, 320 Sparkman Dr, Huntsville, AL 35805 (United States); Kuzin, S. [Lebedev Physical Institute, Russian Academy of Sciences, Leninskii pr. 53, Moscow, 119991 (Russian Federation); DeForest, C. E. [Southwest Research Institute, 1050 Walnut Street Suite 300, Boulder, CO 80302 (United States)

    2014-04-01T23:59:59.000Z

    Observing the Sun at high time and spatial scales is a step toward understanding the finest and fundamental scales of heating events in the solar corona. The high-resolution coronal (Hi-C) instrument has provided the highest spatial and temporal resolution images of the solar corona in the EUV wavelength range to date. Hi-C observed an active region on 2012 July 11 that exhibits several interesting features in the EUV line at 193 Å. One of them is the existence of short, small brightenings 'sparkling' at the edge of the active region; we call these EUV bright dots (EBDs). Individual EBDs have a characteristic duration of 25 s with a characteristic length of 680 km. These brightenings are not fully resolved by the SDO/AIA instrument at the same wavelength; however, they can be identified with respect to the Hi-C location of the EBDs. In addition, EBDs are seen in other chromospheric/coronal channels of SDO/AIA, which suggests a temperature between 0.5 and 1.5 MK. Based on their frequency in the Hi-C time series, we define four different categories of EBDs: single peak, double peak, long duration, and bursty. Based on a potential field extrapolation from an SDO/HMI magnetogram, the EBDs appear at the footpoints of large-scale, trans-equatorial coronal loops. The Hi-C observations provide the first evidence of small-scale EUV heating events at the base of these coronal loops, which have a free magnetic energy of the order of 10{sup 26} erg.

  12. Sparkling extreme-ultraviolet bright dots observed with Hi-C | OSTI, US

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol HomeFacebookScholarship Fund3Biology|Solar windMarchSpace-AgeSpacerSpark

  13. Ultraviolet emissions from Gd3 + ions excited by energy transfer

    E-Print Network [OSTI]

    Cao, Wenwu

    Ultraviolet emissions from Gd3 + ions excited by energy transfer from Ho3 + ions Ying Yu October 2010 Accepted 28 October 2010 Available online 4 November 2010 Keywords: Ultraviolet emission Upconversion Energy transfer a b s t r a c t Ultraviolet (UV) upconversion (UC) emissions of Gd3+ ion were

  14. Microwave-driven ultraviolet light sources

    SciTech Connect (OSTI)

    Manos, Dennis M. (Williamsburg, VA); Diggs, Jessie (Norfolk, VA); Ametepe, Joseph D. (Roanoke, VA)

    2002-01-29T23:59:59.000Z

    A microwave-driven ultraviolet (UV) light source is provided. The light source comprises an over-moded microwave cavity having at least one discharge bulb disposed within the microwave cavity. At least one magnetron probe is coupled directly to the microwave cavity.

  15. Solar extreme events

    E-Print Network [OSTI]

    Hudson, Hugh S

    2015-01-01T23:59:59.000Z

    Solar flares and CMEs have a broad range of magnitudes. This review discusses the possibility of "extreme events," defined as those with magnitudes greater than have been seen in the existing historical record. For most quantitative measures, this direct information does not extend more than a century and a half into the recent past. The magnitude distributions (occurrence frequencies) of solar events (flares/CMEs) typically decrease with the parameter measured or inferred (peak flux, mass, energy etc. Flare radiation fluxes tend to follow a power law slightly flatter than $S^{-2}$, where S represents a peak flux; solar particle events (SPEs) follow a still flatter power law up to a limiting magnitude, and then appear to roll over to a steeper distribution, which may take an exponential form or follow a broken power law. This inference comes from the terrestrial $^{14}$C record and from the depth dependence of various radioisotope proxies in the lunar regolith and in meteorites. Recently major new observation...

  16. Ultraviolet radiation in the southern seas in early spring 1993

    SciTech Connect (OSTI)

    Wendler, G.; Quakenbush, T. [Univ. of Alaska, Fairbanks, AK (United States)

    1994-12-31T23:59:59.000Z

    The National Science Foundation research vessel Nathaniel B. Palmer carried out a cruise to Antarctica in early spring of 1993. It left Punta Arenas, Chile, close to the tip of South America on 11 August 1993. sailed south for 3 days to the tip of The Antarctic Peninsula, stopping at O`Higgens and Palmer Stations, and from there went southwest and into the Bellingshausen sea. On 10 September, it reached the most southerly position, 71{degrees}S, some distance north of the Thurston Island. From there, it went as far as 110{degrees}W before returning to Punta Arenas. The main purpose of the cruise was to investigate the snow- and sea-ice thickness, properties, and structures in this part of the southern oceans. It also allowed us to carry out continuous radiation measurements. We measured the following fluxes: global radiation (Eppley PSP), infrared incoming radiation (Eppley Pyrgeometer PIR), ultraviolet-A radiation (Eppley UV meter), ultraviolet-B radiation (Yankee Environmental Systems), and pitch and roll of the ship (Lucas Sensing Systems, Inc.). All instruments were sampled twice per second (Campbell Scientific, Model 21 X), and a notebook computer (ASI Patriot) stored 1-minute averages of the radiation data and 1-minute standard deviation of the ship`s pitch and roll. Visual observations of cloud cover were also recorded. 2 refs., 3 figs.

  17. Viability of Cladosporium herbarum spores under 157 nm laser and vacuum ultraviolet irradiation, low temperature (10 K) and vacuum

    SciTech Connect (OSTI)

    Sarantopoulou, E., E-mail: esarant@eie.gr; Stefi, A.; Kollia, Z.; Palles, D.; Cefalas, A. C. [National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635 (Greece); Petrou, P. S.; Bourkoula, A.; Koukouvinos, G.; Kakabakos, S. [N.C.S.R. “Demokritos”, Institute for Nuclear and Radiological Sciences, Energy, Technology and Safety, Patriarchou Gregoriou Str. Aghia Paraskevi, Athens 15310 (Greece); Velentzas, A. D. [University of Athens, Faculty of Biology, Department of Cell Biology and Biophysics, Athens 15784 (Greece)

    2014-09-14T23:59:59.000Z

    Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm?²) or vacuum-ultraviolet irradiation (110–180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, ?-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance in spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.

  18. Extreme events in excitable systems and mechanisms of their generation

    E-Print Network [OSTI]

    Gerrit Ansmann; Rajat Karnatak; Klaus Lehnertz; Ulrike Feudel

    2014-08-27T23:59:59.000Z

    We study deterministic systems, composed of excitable units of FitzHugh-Nagumo type, that are capable of self-generating and self-terminating strong deviations from their regular dynamics without the influence of noise or parameter change. These deviations are rare, short-lasting, and recurrent and can therefore be regarded as extreme events. Employing a range of methods we analyze dynamical properties of the systems, identifying features in the systems' dynamics that may qualify as precursors to extreme events. We investigate these features and elucidate mechanisms that may be responsible for the generation of the extreme events.

  19. Study of extreme nuclear shapes in extreme conditions

    SciTech Connect (OSTI)

    Banerjee, Sudhee Ranjan, E-mail: srb@vecc.gov.in [Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata 700 064 (India)

    2014-08-14T23:59:59.000Z

    Studies of extreme nuclear shapes have always fascinated scientists and are being pursued quite strongly over the years. Nuclei present themselves with interesting shapes and structures at different conditions of spin, excitation and also with the number of neutrons and/or protons in them. Gamma decays from the Giant dipole Resonances in nuclei can probe directly their shapes at different extreme conditions by looking at their resonant line-shapes, e.g., Jacobi shapes and shape-transitions, super/hyper-deformation etc. Similar such studies, done for the first time, using the LAMBDA high energy gamma spectrometer developed at VECC, is discussed here.

  20. Ultraviolet Resonant Raman Enhancements in the Detection of Explosives

    SciTech Connect (OSTI)

    Short, B J; Carter, J C; Gunter, D; Hovland, P; Jagode, H; Karavanic, K; Marin, G; Mellor-Crummey, J; Moore, S; Norris, B; Oliker, L; Olschanowsky, C; Roth, P C; Schulz, M; Shende, S; Snavely, A; Spear, W

    2009-06-03T23:59:59.000Z

    Raman-based spectroscopy is potentially militarily useful for standoff detection of high explosives. Normal (non-resonance) and resonance Raman spectroscopies are both light scattering techniques that use a laser to measure the vibrational spectrum of a sample. In resonance Raman, the laser is tuned to match the wavelength of a strong electronic absorbance in the molecule of interest, whereas, in normal Raman the laser is not tuned to any strong electronic absorbance bands. The selection of appropriate excitation wavelengths in resonance Raman can result in a dramatic increase in the Raman scattering efficiency of select band(s) associated with the electronic transition. Other than the excitation wavelength, however, resonance Raman is performed experimentally the same as normal Raman. In these studies, normal and resonance Raman spectral signatures of select solid high explosive (HE) samples and explosive precursors were collected at 785 nm, 244 nm and 229 nm. Solutions of PETN, TNT, and explosive precursors (DNT & PNT) in acetonitrile solvent as an internal Raman standard were quantitatively evaluated using ultraviolet resonance Raman (UVRR) microscopy and normal Raman spectroscopy as a function of power and select excitation wavelengths. Use of an internal standard allowed resonance enhancements to be estimated at 229 nm and 244 nm. Investigations demonstrated that UVRR provided {approx}2000-fold enhancement at 244 nm and {approx}800-fold improvement at 229 nm while PETN showed a maximum of {approx}25-fold at 244 nm and {approx}190-fold enhancement at 229 nm solely from resonance effects when compared to normal Raman measurements. In addition to the observed resonance enhancements, additional Raman signal enhancements are obtained with ultraviolet excitation (i.e., Raman scattering scales as !4 for measurements based on scattered photons). A model, based partly on the resonance Raman enhancement results for HE solutions, is presented for estimating Raman enhancements for solid HE samples.

  1. The Extremes Toolkit (extRemes) Weather and Climate Applications

    E-Print Network [OSTI]

    Gilleland, Eric

    · R is a language and environment for statistical computing and graphics. · It's Free! · Curiously with a high-level language capable of advanced statistical applications. · Available to a wide audience (not for Statistical Computing extRemes is written in and requires R, but does not require familiarity with R. About R

  2. Extreme Conditions Modeling Workshop Report

    SciTech Connect (OSTI)

    Coe, R. G.; Neary, V. S.; Lawson, M. J.; Yu, Y.; Weber, J.

    2014-07-01T23:59:59.000Z

    Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, NM on May 13th-14th, 2014. The objective of the workshop was to review the current state of knowledge on how to model WECs in extreme conditions (e.g. hurricanes and other large storms) and to suggest how U.S. Department of Energy (DOE) and national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry.

  3. ULTRAVIOLET EXTINCTION AT HIGH GALACTIC LATITUDES

    SciTech Connect (OSTI)

    Peek, J. E. G.; Schiminovich, David, E-mail: jegpeek@gmail.com [Department of Astronomy, Columbia University, New York, NY (United States)

    2013-07-01T23:59:59.000Z

    In order to study the properties and effects of high Galactic latitude dust, we present an analysis of 373,303 galaxies selected from the Galaxy Evolution Explorer All-Sky Survey and Wide-field Infrared Explorer All-Sky Data Release. By examining the variation in aggregate ultraviolet colors and number density of these galaxies, we measure the extinction curve at high latitude. We additionally consider a population of spectroscopically selected galaxies from the Sloan Digital Sky Survey to measure extinction in the optical. We find that dust at high latitude is neither quantitatively nor qualitatively consistent with standard reddening laws. Extinction in the FUV and NUV is {approx}10% and {approx}35% higher than expected, with significant variation across the sky. We find that no single R{sub V} parameter fits both the optical and ultraviolet extinction at high latitude, and that while both show detectable variation across the sky, these variations are not related. We propose that the overall trends we detect likely stem from an increase in very small silicate grains in the interstellar medium.

  4. Extremely high frequency RF effects on electronics.

    SciTech Connect (OSTI)

    Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

    2012-01-01T23:59:59.000Z

    The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

  5. 1, 255285, 2005 Extreme climates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , orography, and oceanic heat transport on extreme climates V. Romanova 1 , G. Lohmann 2,1 , and K. Grosfeld 2 to assess the possibility that land albedo, atmospheric CO2, orography and oceanic heat transport may cause5-covered Earth is the high land albedo in combination with initial temperatures set equal to the freezing point

  6. Ultraviolet laser beam monitor using radiation responsive crystals

    DOE Patents [OSTI]

    McCann, Michael P. (Oliver Springs, TN); Chen, Chung H. (Knoxville, TN)

    1988-01-01T23:59:59.000Z

    An apparatus and method for monitoring an ultraviolet laser beam includes disposing in the path of an ultraviolet laser beam a substantially transparent crystal that will produce a color pattern in response to ultraviolet radiation. The crystal is exposed to the ultraviolet laser beam and a color pattern is produced within the crystal corresponding to the laser beam intensity distribution therein. The crystal is then exposed to visible light, and the color pattern is observed by means of the visible light to determine the characteristics of the laser beam that passed through crystal. In this manner, a perpendicular cross sectional intensity profile and a longitudinal intensity profile of the ultraviolet laser beam may be determined. The observation of the color pattern may be made with forward or back scattered light and may be made with the naked eye or with optical systems such as microscopes and television cameras.

  7. Extremism

    Office of Scientific and Technical Information (OSTI)

    Within the past several years, a cell of three Americans who started spying for East Germany during the 1970s and a group of 12 people spying for the Cuban government have been...

  8. Extremism

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn AprilAElectronic InputRudolphMATERIALS TECHNOLOGYAccelerating CarbonHierarchyi LEFT-WING

  9. Controlled doping of graphene using ultraviolet irradiation

    SciTech Connect (OSTI)

    Luo Zhengtang [Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong); Pinto, Nicholas J.; Davila, Yarely [Department of Physics and Electronics, University of Puerto Rico at Humacao, Humacao, 00792 (Puerto Rico); Charlie Johnson, A. T. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396 (United States)

    2012-06-18T23:59:59.000Z

    The electronic properties of graphene are tunable via doping, making it attractive in low dimensional organic electronics. Common methods of doping graphene, however, adversely affect charge mobility and degrade device performance. We demonstrate a facile shadow mask technique of defining electrodes on graphene grown by chemical vapor deposition (CVD) thereby eliminating the use of detrimental chemicals needed in the corresponding lithographic process. Further, we report on the controlled, effective, and reversible doping of graphene via ultraviolet (UV) irradiation with minimal impact on charge mobility. The change in charge concentration saturates at {approx}2 Multiplication-Sign 10{sup 12} cm{sup -2} and the quantum yield is {approx}10{sup -5} e/photon upon initial UV exposure. This simple and controlled strategy opens the possibility of doping wafer-size CVD graphene for diverse applications.

  10. Ultraviolet laser ablation of polycarbonate and glass in air

    SciTech Connect (OSTI)

    Bormotova, T. A.; Blumenthal, R. [Auburn University, Alabama 36849 (United States)

    2009-02-01T23:59:59.000Z

    The fundamental physical processes that follow ultraviolet laser ablation of polycarbonate and borosilicate glass in air have been investigated using photodeflection as a function of the distance from the surface to probe laser. Four features were observed in the data sets for each material. Two of these features correlate well with gas dynamical predictions for the expansion of the shock wave and gas plume. The third feature is consistent with the propagation of the popping sound of the laser ablation event. The final feature, which occurs at very early times and does not shift significantly in time as the surface to probe distance is increased from 0 to greater than 6 mm, has been tentatively ascribed to the ejection of fast electrons. The final significant observation is complete blocking of the probe laser, only observed during borosilicate ablation, which is attributed to scattering of the probe laser light by macroscopic SiO{sub x} particles that grow in the final stages of plume expansion and cooling.

  11. Quantitative imaging of living cells by deep ultraviolet microscopy

    E-Print Network [OSTI]

    Zeskind, Benjamin J

    2006-01-01T23:59:59.000Z

    Developments in light microscopy over the past three centuries have opened new windows into cell structure and function, yet many questions remain unanswered by current imaging approaches. Deep ultraviolet microscopy ...

  12. ARM - Measurement - Extreme event time

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particle ARMgovMeasurementsExtreme event

  13. Lamp for generating high power ultraviolet radiation

    DOE Patents [OSTI]

    Morgan, Gary L. (Elkridge, MD); Potter, James M. (Los Alamos, NM)

    2001-01-01T23:59:59.000Z

    The apparatus is a gas filled ultraviolet generating lamp for use as a liquid purifier. The lamp is powred by high voltage AC, but has no metallic electrodes within or in contact with the gas enclosure which is constructed as two concentric quartz cylinders sealed together at their ends with the gas fill between the cylinders. Cooling liquid is pumped through the volume inside the inner quartz cylinder where an electrically conductive pipe spaced from the inner cylinder is used to supply the cooling liquid and act as the high voltage electrode. The gas enclosure is enclosed within but spaced from a metal housing which is connected to operate as the ground electrode of the circuit and through which the treated fluid flows. Thus, the electrical circuit is from the central pipe, and through the cooling liquid, the gas enclosure, the treated liquid on the outside of the outer quartz cylinder, and to the housing. The high voltage electrode is electrically isolated from the source of cooling liquid by a length of insulated hose which also supplies the cooling liquid.

  14. Intense ultraviolet perturbations on aquatic primary producers

    E-Print Network [OSTI]

    Guimarais, Mayrene; Horvath, Jorge

    2010-01-01T23:59:59.000Z

    During the last decade, the hypothesis that one or more biodiversity drops in the Phanerozoic eon, evident in the geological record, might have been caused by the most powerful kind of stellar explosion so far known (Gamma Ray Bursts) has been discussed in several works. These stellar explosions could have left an imprint in the biological evolution on Earth and in other habitable planets. In this work we calculate the short-term lethality that a GRB would produce in the aquatic primary producers on Earth. This effect on life appears as a result of ultraviolet (UV) re-transmission in the atmosphere of a fraction of the gamma energy, resulting in an intense UV flash capable of penetrating ~ tens of meters in the water column in the ocean. We focus on the action of the UV flash on phytoplankton, as they are the main contributors to global aquatic primary productivity. Our results suggest that the UV flash could cause an hemispheric reduction of phytoplankton biomass in the upper mixed layer of the World Ocean o...

  15. Vacuum ultraviolet photoionization of carbohydrates and nucleotides

    SciTech Connect (OSTI)

    Shin, Joong-Won, E-mail: jshin@govst.edu [Division of Science, Governors State University, University Park, Illinois 60484-0975 (United States) [Division of Science, Governors State University, University Park, Illinois 60484-0975 (United States); Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872 (United States); Bernstein, Elliot R., E-mail: erb@lamar.colostate.edu [Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872 (United States)

    2014-01-28T23:59:59.000Z

    Carbohydrates (2-deoxyribose, ribose, and xylose) and nucleotides (adenosine-, cytidine-, guanosine-, and uridine-5{sup ?}-monophosphate) are generated in the gas phase, and ionized with vacuum ultraviolet photons (VUV, 118.2 nm). The observed time of flight mass spectra of the carbohydrate fragmentation are similar to those observed [J.-W. Shin, F. Dong, M. Grisham, J. J. Rocca, and E. R. Bernstein, Chem. Phys. Lett. 506, 161 (2011)] for 46.9 nm photon ionization, but with more intensity in higher mass fragment ions. The tendency of carbohydrate ions to fragment extensively following ionization seemingly suggests that nucleic acids might undergo radiation damage as a result of carbohydrate, rather than nucleobase fragmentation. VUV photoionization of nucleotides (monophosphate-carbohydrate-nucleobase), however, shows that the carbohydrate-nucleobase bond is the primary fragmentation site for these species. Density functional theory (DFT) calculations indicate that the removed carbohydrate electrons by the 118.2 nm photons are associated with endocyclic C–C and C–O ring centered orbitals: loss of electron density in the ring bonds of the nascent ion can thus account for the observed fragmentation patterns following carbohydrate ionization. DFT calculations also indicate that electrons removed from nucleotides under these same conditions are associated with orbitals involved with the nucleobase-saccharide linkage electron density. The calculations give a general mechanism and explanation of the experimental results.

  16. Extreme hydro-meteorological events and their probabilities

    E-Print Network [OSTI]

    Beersma, Jules

    Extreme hydro-meteorological events and their probabilities Jules Beersma #12;Promotor: Prof. dr. A Onderzoekschool (BBOS) #12;Extreme hydro-meteorological events and their probabilities Extreme hydro

  17. Granular gases under extreme driving

    E-Print Network [OSTI]

    W. Kang; J. Machta; E. Ben-Naim

    2010-08-06T23:59:59.000Z

    We study inelastic gases in two dimensions using event-driven molecular dynamics simulations. Our focus is the nature of the stationary state attained by rare injection of large amounts of energy to balance the dissipation due to collisions. We find that under such extreme driving, with the injection rate much smaller than the collision rate, the velocity distribution has a power-law high energy tail. The numerically measured exponent characterizing this tail is in excellent agreement with predictions of kinetic theory over a wide range of system parameters. We conclude that driving by rare but powerful energy injection leads to a well-mixed gas and constitutes an alternative mechanism for agitating granular matter. In this distinct nonequilibrium steady-state, energy cascades from large to small scales. Our simulations also show that when the injection rate is comparable with the collision rate, the velocity distribution has a stretched exponential tail.

  18. Spectroscopic investigations of the vibrational potential energy surfaces in electronic ground and excited states

    E-Print Network [OSTI]

    Yang, Juan

    2007-09-17T23:59:59.000Z

    The vibrational potential energy surfaces in electronic ground and excited states of several ring molecules were investigated using several different spectroscopic methods, including far-infrared (IR), Raman, ultraviolet (UV) absorption...

  19. Phase transition between non-extremal and extremal Reissner-Nordström black holes

    E-Print Network [OSTI]

    Yun Soo Myung

    2008-03-11T23:59:59.000Z

    We discuss the phase transition between non-extremal and extremal Reissner-Nordstr\\"om black holes. This transition is considered as the $T \\to 0$ limit of the transition between the non-extremal and near-extremal black holes. We show that an evaporating process from non-extremal black hole to extremal one is possible to occur, but its reverse process is not possible to occur because of the presence of the maximum temperature. Furthermore, it is shown that the Hawking-Page phase transition between small and large black holes unlikely occurs in the AdS Reissner-Nordstr\\"om black holes.

  20. Extreme Scale Computing, Co-design

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

    at Extreme Scale (ACES) partnership to design and develop the supercomputer Cielo (Spanish for "sky"), which was built by Cray Inc. Cielo can perform more than one quadrillion...

  1. Extremely Hazardous Substances Risk Management Act (Delaware)

    Broader source: Energy.gov [DOE]

    This act lays out provisions for local governments to implement regulations and standards for the management of extremely hazardous substances, which are defined and categorized as follows:

  2. The Near-Ultraviolet Continuum of Late-Type Stars

    E-Print Network [OSTI]

    Carlos Allende Prieto; David L. Lambert

    2000-01-28T23:59:59.000Z

    Analyses of the near-ultraviolet continuum of late-type stars have led to controversial results regarding the performance of state-of-the-art model atmospheres. The release of the homogeneous IUE final archive and the availability of the high-accuracy Hipparcos parallaxes provide an opportunity to revisit this issue, as accurate stellar distances make it possible to compare observed absolute fluxes with the predictions of model atmospheres. The near-UV continuum is highly sensitive to Teff and [Fe/H], and once the gravity is constrained from the parallax, these parameters may be derived from the analysis of low-dispersion "long-wavelength" (2000-3000 A) IUE spectra for stars previously studied by Alonso et al. (1996; A&AS 117, 227) using the Infrared Flux Method (IRFM). A second comparison is carried out against the stars spectroscopically investigated by Gratton et al. (1996; A&A 314, 191). It is shown that there is a good agreement between Teffs obtained from the IRFM and from the near-UV continuum, and a remarkable correspondence between observed and synthetic fluxes for stars with 4000 <= Teff <= 6000 K of any metallicity and gravity. These facts suggest that model atmospheres provide an adequate description of the near-UV continuum forming region and that the opacities involved are essentially understood. For cooler stars, the results of the IRFM are no longer reliable, as shown by Alonso et al., but the discrepancy noticed for stars hotter than 6000 K may reflect problems in the model atmospheres and/or the opacities at these higher temperatures.

  3. SWAP OBSERVATIONS OF THE LONG-TERM, LARGE-SCALE EVOLUTION OF THE EXTREME-ULTRAVIOLET SOLAR CORONA

    SciTech Connect (OSTI)

    Seaton, Daniel B.; De Groof, Anik; Berghmans, David; Nicula, Bogdan [Royal Observatory of Belgium-SIDC, Avenue Circulaire 3, B-1180 Brussels (Belgium); Shearer, Paul [Department of Mathematics, 2074 East Hall, University of Michigan, 530 Church Street, Ann Arbor, MI 48109-1043 (United States)

    2013-11-01T23:59:59.000Z

    The Sun Watcher with Active Pixels and Image Processing (SWAP) EUV solar telescope on board the Project for On-Board Autonomy 2 spacecraft has been regularly observing the solar corona in a bandpass near 17.4 nm since 2010 February. With a field of view of 54 × 54 arcmin, SWAP provides the widest-field images of the EUV corona available from the perspective of the Earth. By carefully processing and combining multiple SWAP images, it is possible to produce low-noise composites that reveal the structure of the EUV corona to relatively large heights. A particularly important step in this processing was to remove instrumental stray light from the images by determining and deconvolving SWAP's point-spread function from the observations. In this paper, we use the resulting images to conduct the first-ever study of the evolution of the large-scale structure of the corona observed in the EUV over a three year period that includes the complete rise phase of solar cycle 24. Of particular note is the persistence over many solar rotations of bright, diffuse features composed of open magnetic fields that overlie polar crown filaments and extend to large heights above the solar surface. These features appear to be related to coronal fans, which have previously been observed in white-light coronagraph images and, at low heights, in the EUV. We also discuss the evolution of the corona at different heights above the solar surface and the evolution of the corona over the course of the solar cycle by hemisphere.

  4. Development of extreme ultraviolet and soft x-ray multilayer optics for scientific studies with femtosecond/attosecond sources

    E-Print Network [OSTI]

    Aquila, Andrew Lee

    2009-01-01T23:59:59.000Z

    Dispersion . . . . . . . . . . . . . 2.2.3 Optics for Pulse4.3.2 Optic Development . . . . . . . . .of EUV Multilayer Optics . . . . . 3.1.1 The Necessity of

  5. Probing temporal evolution of extreme ultraviolet assisted contamination on Ru mirror by x-ray photoelectron spectroscopy

    E-Print Network [OSTI]

    Harilal, S. S.

    of hydrocarbons8 and the oxidation of the near sur- face atomic layers of Ru eventually lead to the degradation and oxidation of the Ru mirror surface, and the corresponding impact on reflectivity were studied. In particular analyses show a slight increase in Ru oxide, whereas the concentration of water molecules decreases

  6. High-resolution tangential absolute extreme ultraviolet arrays for radiated power density measurements on NSTX-U

    SciTech Connect (OSTI)

    Delgado-Aparicio, L.; Bell, R. E.; Diallo, A.; Gerhardt, S. P.; Kozub, T. A.; LeBlanc, B. P.; Stratton, B. C. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Faust, I. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Tritz, K. [The Johns Hopkins University, Baltimore, Maryland 21209 (United States)

    2014-11-15T23:59:59.000Z

    The radiated-power-density diagnostic on the equatorial midplane for the NSTX-U tokamak will be upgraded to measure the radial structure of the photon emissivity profile with an improved radial resolution. This diagnostic will enhance the characterization and studies of power balance, impurity transport, and MHD. The layout and response expected of the new system is shown for different plasma conditions and impurity concentrations. The effect of toroidal rotation driving poloidal asymmetries in the core radiation from high-Z impurities is also addressed.

  7. January 1983 / Vol. 8, No. 1 / OPTICS LETTERS 21 Dichroic beam splitter for extreme-ultraviolet and visible

    E-Print Network [OSTI]

    Bokor, Jeffrey

    and UV laser beamsis demonstrated. The devicehas high XUV reflection efficiency(R - 44%)and highdam- age the generatedharmonic inthe XUV. This intense fundamental beam can destroy a sample or saturate detectors of absorbing largeenergy fluxes from pulsed lasers used to generate the XLUV radiation. A typical damage limit

  8. ARE CORONAE OF MAGNETICALLY ACTIVE STARS HEATED BY FLARES? II. EXTREME ULTRAVIOLET AND X-RAY FLARE STATISTICS AND THE

    E-Print Network [OSTI]

    Audard, Marc

    @astro.columbia.edu Vinay L. Kashyap and Jeremy J. Drake Harvard-Smithsonian Center for Astrophysics, 60 Garden Street distribution in radiated energy of the late-type active star AD Leo. Occurrence rates of solar flares have almost 2 orders of magnitude in their radiated energy. We compare the observed light curves with light

  9. Extreme-ultraviolet spectra of highly charged Pt ions with several valence-shell electrons: Observation and accurate calculations

    SciTech Connect (OSTI)

    Traebert, Elmar [Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550-9234 (United States); Astronomisches Institut, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Clementson, Joel; Beiersdorfer, Peter [Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550-9234 (United States); Santana, Juan A.; Ishikawa, Yasuyuki [Department of Chemistry and Chemical Physics Program, University of Puerto Rico, P.O. Box 23346, San Juan, Puerto Rico 00931-3346 (Puerto Rico)

    2010-12-15T23:59:59.000Z

    Previous observations of Cu- through Ge-like high-Z ions have demonstrated that accurate measurements and theory agree well for ions with a single valence electron but that additional electrons in the valence shell cause progressively worsening computational problems. We have obtained highly resolved euv spectra of Pt (Z=78) ions in an electron-beam ion trap. The measured wavelengths are compared to the results of a number of recent large-scale calculations, including our own multireference Moeller-Plesset computations. The latter calculations match the best for Cu- and Zn-like ions and represent an order-of-magnitude improvement in predictive accuracy for Ga- and Ge-like ions.

  10. Extreme-ultraviolet spectral purity and magnetic ion debris mitigation by use of low-density tin targets

    E-Print Network [OSTI]

    Harilal, S S; Tillack, Mark S; O'Shay, Beau; Tao, Y; Paguio, R; Nikroo, A

    2006-01-01T23:59:59.000Z

    The UTA obtained from full density tin and 0.5% Sn density.The UTA spectrum from tin doped foam targets showed distincta) and 0.5 % density (b) tin in the presence and absence of

  11. Atmosphere of a sunspot based on observations in the x-ray, extreme ultraviolet, optical, and radio ranges

    SciTech Connect (OSTI)

    Staude, J.; Fuerstenberg, F.; Hildebrandt, J.; Krueger, A.; Jakimiec, J.; Obridko, V.N.; Siarkowski, M.; Sylwester, B.; Sylwester, J.

    1984-09-01T23:59:59.000Z

    It is shown that the lower chromosphere of an umbra is best described within the framework of a model close to that of Teplitskaya et al. This model can be extended to higher levels using a large temperature gradient, so that Troughly-equal40 000 K and an electron density n/sub e/roughly-equal4x10/sup 10/ cm/sup -3/ are reached at a height zroughly-equal2000 km above the umbral photosphere. These values are defined by the EUV data of the HRTS instrument. At higher levels one must presume the existence of at least two components: The hot component, which occupies ..cap alpha..roughly-equal0.8--0.9 of the total volume, has a narrow transition layer, and the coronal values of Troughly-equal1.8x10/sup 6/ K and n/sub e/roughly-equal5x10/sup 8/ even at a height z = 3000--5000 km. These values are consistent both with the absence of an x-ray emission flux above large sunspots and with the high brightness temperature T/sub b/ = 1.8x10/sup 6/ K of emission in the centimeter range from the same region. This hot coronal matter surrounds the bases of cool loops emerging from the umbra in the form of bundles, and they emit the EUV lines observed at 10/sup 4/< or =T< or =10/sup 6/ K. In the corona the z dependence of all the physical quantities, including ..cap alpha.., over a distance of several thousand kilometers can be taken as weak. Along the axis of a loop T grows slowly, the loops become more horizontal, and at distances and heights of several tens of thousands of kilometers above a flocculus they appear as hot x-ray loops.

  12. Development of extreme ultraviolet and soft x-ray multilayer optics for scientific studies with femtosecond/attosecond sources

    E-Print Network [OSTI]

    Aquila, Andrew Lee

    2009-01-01T23:59:59.000Z

    on how short an electromagnetic pulse can be. Derivation ofis essential for electromagnetic pulse measurements. In theof the electromagnetic spectrum. Visible light pulses can

  13. STUDYING LARGE- AND SMALL-SCALE ENVIRONMENTS OF ULTRAVIOLET LUMINOUS GALAXIES

    SciTech Connect (OSTI)

    Basu-Zych, Antara R.; Schiminovich, David [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States); Heinis, Sebastien; Heckman, Tim; Bianchi, Luciana [Center for Astrophysical Sciences, The Johns Hopkins' University, 3400 N. Charles St., Baltimore, MD 21218 (United States); Overzier, Roderik [Max-Planck-Institut fuer Astrophysik, D-85748 Garching (Germany); Zamojski, Michel; Barlow, Tom A.; Conrow, Tim; Forster, Karl G.; Friedman, Peter G.; Martin, D. Christopher; Morrissey, Patrick [California Institute of Technology, MC 405-47, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Ilbert, Olivier [Institute for Astronomy, 2680 Woodlawn Dr., University of Hawaii, Honolulu, HI 96822 (United States); Koekemoer, Anton M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Donas, Jose; Milliard, Bruno [Laboratoire d'Astrophysique de Marseille, BP8, Traverse du Siphon, F-13376 Marseille (France); Lee, Young-Wook [Center for Space Astrophysics, Yonsei University, Seoul 120-749 (Korea, Republic of); Madore, Barry F. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Neff, Susan G. [Laboratory for Astronomy and Solar Physics, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)], E-mail: antara@astro.columbia.edu (and others)

    2009-07-10T23:59:59.000Z

    Studying the environments of 0.4 < z < 1.2 ultraviolet (UV)-selected galaxies, as examples of extreme star-forming galaxies (with star formation rates (SFRs) in the range of 3-30 M{sub sun} yr{sup -1}), we explore the relationship between high rates of star formation, host halo mass, and pair fractions. We study the large- and small-scale environments of local ultraviolet luminous galaxies (UVLGs) by measuring angular correlation functions. We cross-correlate these systems with other galaxy samples: a volume-limited sample (ALL), a blue luminous galaxy sample, and a luminous red galaxy (LRG) sample. We determine the UVLG comoving correlation length to be r{sub 0} = 4.8{sup +11.6}{sub -2.4} h {sup -1} Mpc at (z) = 1.0, which is unable to constrain the halo mass for this sample. However, we find that UVLGs form close (separation <30 kpc) pairs with the ALL sample, but do not frequently form pairs with LRGs. A rare subset of UVLGs, those with the highest FUV surface brightnesses, are believed to be local analogs of high-redshift Lyman break galaxies (LBGs) and are called Lyman break analogs (LBAs). LBGs and LBAs share similar characteristics (i.e., color, size, surface brightness, specific SFRs, metallicities, and dust content). Recent Hubble Space Telescope images of z {approx} 0.2 LBAs show disturbed morphologies, signs of mergers and interactions. UVLGs may be influenced by interactions with other galaxies and we discuss this result in terms of other high star-forming, merging systems.

  14. Inhibition of Photosynthesis in Some Algae by Extreme-Red Light Author(s): Eugene Rabinowitch, Govindjee, Jan B. Thomas

    E-Print Network [OSTI]

    Govindjee

    Inhibition of Photosynthesis in Some Algae by Extreme-Red Light Author(s): Eugene Rabinowitch://www.jstor.org #12;Inhibition of Photosynthesis in Some Algae by Extreme"Red Light Abstract. Photosynthesis produced by far-red light (about 700 m,b) is reversibly inhibited in some algae by extreme-red light ( 750 m

  15. On-board Measurement of NO and NO2 using Non-dispersive Ultraviolet...

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

    board Measurement of NO and NO2 using Non-dispersive Ultraviolet (NDUV) Spectroscopy On-board Measurement of NO and NO2 using Non-dispersive Ultraviolet (NDUV) Spectroscopy...

  16. Could the Earth's surface Ultraviolet irradiance be blamed for the global warming? A new effect may exist

    E-Print Network [OSTI]

    Chen, Jilong; Zhao, Juan; Zheng, Yujun

    2014-01-01T23:59:59.000Z

    Whether natural factors could interpret the rise of the Earth's surface temperature is still controversial. Though numerous recent researches have reported apparent correlations between solar activity and the Earth's climate, solar activity has encountered a big problem when describing the rapid global warming after 1970s. Our investigation shows the good positive correlations between the Earth's surface Ultraviolet irradiance (280-400 nm) and the Earth's surface temperature both in temporal and spatial variations by analyzing the global surface Ultraviolet irradiance (280-400 nm) and global surface temperature data from 1980-1999. The rise of CO$_2$ cannot interpret the good positive correlations, and we could even get an opposite result to the good correlations when employing the rise of CO$_2$ to describe the relation between them. Based on the good positive correlations, we suggest a new effect, named "Highly Excited Water Vapor" (HEWV) effect, which can interpret how the Sun influences the Earth's surfac...

  17. Electron and proton aurora observed spectroscopically in the far ultraviolet

    E-Print Network [OSTI]

    Lummerzheim, Dirk

    Electron and proton aurora observed spectroscopically in the far ultraviolet M. Galand,1 D the location of the electron and proton aurorae is discussed. The estimation of the particle characteristics aurora. Because protons and electrons do not interact in the same way with the atmosphere, our study

  18. Time resolved ultraviolet absorption spectroscopy of pulsed fluorocarbon plasmas

    E-Print Network [OSTI]

    Gleason, Karen K.

    Time resolved ultraviolet absorption spectroscopy of pulsed fluorocarbon plasmas Brett A. Cruden.1063/1.1334936 I. INTRODUCTION The study of fluorocarbon plasmas is of great interest for their applications in silicon dioxide etching.1,2 Recently, at- tention has been paid to using fluorocarbon plasmas to pro- duce

  19. A Network Contention Model for the Extreme-scale Simulator

    SciTech Connect (OSTI)

    Engelmann, Christian [ORNL; Naughton, III, Thomas J [ORNL

    2015-01-01T23:59:59.000Z

    The Extreme-scale Simulator (xSim) is a performance investigation toolkit for high-performance computing (HPC) hardware/software co-design. It permits running a HPC application with millions of concurrent execution threads, while observing its performance in a simulated extreme-scale system. This paper details a newly developed network modeling feature for xSim, eliminating the shortcomings of the existing network modeling capabilities. The approach takes a different path for implementing network contention and bandwidth capacity modeling using a less synchronous and accurate enough model design. With the new network modeling feature, xSim is able to simulate on-chip and on-node networks with reasonable accuracy and overheads.

  20. Geophysical investigations of certain Montana geothermal areas

    SciTech Connect (OSTI)

    Wideman, C.J. (Montana Bureau of Mines and Geology, Butte); Dye, L.; Halvorson, J.; McRae, M.; Ruscetta, C.A.; Foley, D. (eds.)

    1981-05-01T23:59:59.000Z

    Selected hot springs areas of Montana have been investigated by a variety of geophysical techniques. Resistivity, gravity, seismic, and magnetic methods have been applied during investigations near the hot springs. Because the geology is extremely varied at the locations of the investigations, several geophysical techniques have usually been applied at each site.

  1. Vacuum-Ultraviolet (VUV) Photoionization of Small Methanol and Methanol-Water Clusters

    SciTech Connect (OSTI)

    Kostko, Oleg; Belau, Leonid; Wilson, Kevin R.; Ahmed, Musahid

    2008-04-24T23:59:59.000Z

    In this work, we report on the vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters. Clusters of methanol with water are generated via co-expansion of the gas phase constituents in a continuous supersonic jet expansion of methanol and water seeded in Ar. The resulting clusters are investigated by single photon ionization with tunable vacuum-ultraviolet synchrotron radiation and mass analyzed using reflectron mass spectrometry. Protonated methanol clusters of the form (CH3OH)nH+(n = 1-12) dominate the mass spectrum below the ionization energy of the methanol monomer. With an increase in water concentration, small amounts of mixed clusters of the form (CH3OH n(H2O)H+ (n = 2-11) are detected. The only unprotonated species observed in this work are the methanol monomer and dimer. Appearance energies are obtained from the photoionization efficiency (PIE) curves for CH3OH+, (CH3OH)2+, (CH3OH)nH+ (n = 1-9), and (CH3OH)n(H2O)H+ (n = 2-9) as a function of photon energy. With an increasein the water content in the molecular beam, there is an enhancement of photoionization intensity for the methanol dimer and protonated methanol monomer at threshold. These results are compared and contrasted to previous experimental observations.

  2. Ultraviolet-B Radiation Harms Aquatic Life -Current Results http://www.currentresults.com/Water/Water-Pollution/ultraviolet.php 1 of 2 8/7/2007 1:45 PM

    E-Print Network [OSTI]

    Blaustein, Andrew R.

    Ultraviolet-B Radiation Harms Aquatic Life - Current Results http://www.currentresults.com/Water/Water-Pollution/ultraviolet.php 1 of 2 8/7/2007 1:45 PM Ultraviolet-B Radiation Harms Aquatic Life The first quantitative analysis of published studies on ultraviolet-B (UVB) radiation and water-borne life reveals that UVB causes widespread

  3. Extreme Scaling and Performance across Diverse Architectures...

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

    Extreme Scaling and Performance across Diverse Architectures Start Date: Mar 31 2015 - 11:00am BuildingRoom: Online Webinar Speaker(s): Salman Habib (Argonne National Laboratory;...

  4. Extreme events due to localisation of energy

    E-Print Network [OSTI]

    Colm Mulhern; Stephan Bialonski; Holger Kantz

    2015-01-09T23:59:59.000Z

    We study a one-dimensional chain of harmonically coupled units in an asymmetric anharmonic soft potential. Due to nonlinear localisation of energy, this system exhibits extreme events in the sense that individual elements of the chain show very large excitations. A detailed statistical analysis of extremes in this system reveals some unexpected properties, e.g., a pronounced pattern in the inter event interval statistics. We relate these statistical properties to underlying system dynamics, and notice that often when extreme events occur the system dynamics adopts (at least locally) an oscillatory behaviour, resulting in, for example, a quick succession of such events. The model therefore might serve as a paradigmatic model for the study of the interplay of nonlinearity, energy transport, and extreme events.

  5. Extreme Web Data Integration Keynote @ ICWE 2012

    E-Print Network [OSTI]

    Weske, Mathias

    WILD experience #12;A brief history of data Felix Naumann | Extreme Web Data Integration | ICWE 2012 3 DBMS DBMS DBMS DBMS DBMS DBMS DBMS DBMS DBMS DBMS DBMS DBMS #12;Linked Data & Data Spaces: A database guy`s point

  6. Changes in precipitation characteristics and extremes

    E-Print Network [OSTI]

    Allan, Richard P.

    changes in two different climate scenarios. In the Mediterranean region, precipitation amount, frequencyChanges in precipitation characteristics and extremes Comparing Mediterranean to change Swiss with climate change, with potentially severe impacts on human society and ecosystems. This study analyses

  7. METALLICITY DIFFERENCES IN TYPE Ia SUPERNOVA PROGENITORS INFERRED FROM ULTRAVIOLET SPECTRA

    SciTech Connect (OSTI)

    Foley, Ryan J.; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2013-05-20T23:59:59.000Z

    Two ''twin'' Type Ia supernovae (SNe Ia), SNe 2011by and 2011fe, have extremely similar optical light-curve shapes, colors, and spectra, yet have different ultraviolet (UV) continua as measured in Hubble Space Telescope spectra and measurably different peak luminosities. We attribute the difference in the UV continua to significantly different progenitor metallicities. This is the first robust detection of different metallicities for SN Ia progenitors. Theoretical reasoning suggests that differences in metallicity also lead to differences in luminosity. SNe Ia with higher progenitor metallicities have lower {sup 56}Ni yields and lower luminosities for the same light-curve shape. SNe 2011by and 2011fe have different peak luminosities ({Delta}M{sub V} Almost-Equal-To 0.6 mag), which correspond to different {sup 56}Ni yields: M{sub 11fe}({sup 56}Ni) / M{sub 11by}({sup 56}Ni) = 1.7{sup +0.7}{sub -0.5}. From theoretical models that account for different neutron-to-proton ratios in progenitors, the differences in {sup 56}Ni yields for SNe 2011by and 2011fe imply that their progenitor stars were above and below solar metallicity, respectively. Although we can distinguish progenitor metallicities in a qualitative way from UV data, the quantitative interpretation in terms of abundances is limited by the present state of theoretical models.

  8. Supervisory Investigator

    Broader source: Energy.gov [DOE]

    A successful candidate in this position will... Assist the Investigations Division Director with oversight of CI and counterterrorism (CT) investigative activity at DOE CI Field Offices across DOE...

  9. Extreme Temperature Energy Storage and Generation, for Cost and...

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

    Extreme Temperature Energy Storage and Generation, for Cost and Risk Reduction in Geothermal Exploration Extreme Temperature Energy Storage and Generation, for Cost and Risk...

  10. SUMMARY OF REVISED TORNADO, HURRICANE AND EXTREME STRAIGHT WIND...

    Office of Environmental Management (EM)

    SUMMARY OF REVISED TORNADO, HURRICANE AND EXTREME STRAIGHT WIND CHARACTERISTICS AT NUCLEAR FACILITY SITES SUMMARY OF REVISED TORNADO, HURRICANE AND EXTREME STRAIGHT WIND...

  11. Generating All Efficient Extreme Points in Multiple Objective Linear ...

    E-Print Network [OSTI]

    2007-06-21T23:59:59.000Z

    for generating all efficient extreme points and all efficient extreme rays of a multiple objective linear programming problem (V P). As an application we solve the ...

  12. Nanoscale Phase Transitions under Extreme Conditions within an...

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

    under extreme conditions. Citation: Zhang J, M Lang, RC Ewing, R Devanathan, WJ Weber, and M Toulemonde.2010."Nanoscale Phase Transitions under Extreme Conditions within an...

  13. Inorganic volumetric light source excited by ultraviolet light

    DOE Patents [OSTI]

    Reed, S.; Walko, R.J.; Ashley, C.S.; Brinker, C.J.

    1994-04-26T23:59:59.000Z

    The invention relates to a composition for the volumetric generation of radiation. The composition comprises a porous substrate loaded with a component capable of emitting radiation upon interaction with an exciting radiation. Preferably, the composition is an aerogel substrate loaded with a component, e.g., a phosphor, capable of interacting with exciting radiation of a first energy, e.g., ultraviolet light, to produce radiation of a second energy, e.g., visible light. 4 figures.

  14. Durable Corrosion and Ultraviolet-Resistant Silver Mirror

    DOE Patents [OSTI]

    Jorgensen, G. J.; Gee, R.

    2006-01-24T23:59:59.000Z

    A corrosion and ultra violet-resistant silver mirror for use in solar reflectors; the silver layer having a film-forming protective polymer bonded thereto, and a protective shield overlay comprising a transparent multipolymer film that incorporates a UV absorber. The corrosion and ultraviolet resistant silver mirror retains spectral hemispherical reflectance and high optical clarity throughout the UV and visible spectrum when used in solar reflectors.

  15. Magnetic fluorescent lamp having reduced ultraviolet self-absorption

    DOE Patents [OSTI]

    Berman, Samuel M. (San Francisco, CA); Richardson, Robert W. (Pelham, NY)

    1985-01-01T23:59:59.000Z

    The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly (10) is enhanced by providing means (30) for establishing a magnetic field with lines of force along the path of electron flow through the bulb (12) of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

  16. A high galactic latitude survey of far ultraviolet excess objects

    SciTech Connect (OSTI)

    Bixler, J.V.

    1988-01-01T23:59:59.000Z

    Two closely related efforts in astrophysical instrumentation and observation are described with the objective of performing a high galactic latitude survey of faint objects in the far ultraviolet. The avenues of research possible with data obtained from space based ultraviolet surveys are discussed and a summary of past, present and planned instruments capable of such survey work presented. The Faust telescope, an eight degree field of view imaging instrument with peak sensitivity at 1700A, designed for survey work is described. An imaging, active readout detector and associated ground support equipment were designed, constructed, and calibrated to replace the original photographic detector. The present state of observational data relevant to determining the atmospheric parameters of subdwarf B and O stars, and their mid-Galactic plane density and scale height was reviewed. Theoretical explanations of their evolutionary status were proposed. The optical observations and spectral reductions performed on objects included in a catalog of far ultraviolet bright, high galactic latitude objects are described. These observations provide a sample of subdwarf O and B stars free of brightness and temperature selection effects. A model atmospheres analysis was performed on the subdwarf sample to determine the temperature, gravity and helium to hydrogen ratio of the individual objects. The results show a smooth distribution of objects on the gravity versus temperature diagram near the theoretical location of the extended horizontal branch.

  17. Influences of atmospheric conditions and air mass on the ratio of ultraviolet to total solar radiation

    SciTech Connect (OSTI)

    Riordan, C.J.; Hulstrom, R.L.; Myers, D.R.

    1990-08-01T23:59:59.000Z

    The technology to detoxify hazardous wastes using ultraviolet (UV) solar radiation is being investigated by the DOE/SERI Solar Thermal Technology Program. One of the elements of the technology evaluation is the assessment and characterization of UV solar radiation resources available for detoxification processes. This report describes the major atmospheric variables that determine the amount of UV solar radiation at the earth's surface, and how the ratio of UV-to-total solar radiation varies with atmospheric conditions. These ratios are calculated from broadband and spectral solar radiation measurements acquired at SERI, and obtained from the literature on modeled and measured UV solar radiation. The following sections discuss the atmospheric effects on UV solar radiation and provide UV-to-total solar radiation ratios from published studies, as well as measured values from SERI's data. A summary and conclusions are also given.

  18. Injection locking of a high power ultraviolet laser diode for laser cooling of ytterbium atoms

    E-Print Network [OSTI]

    Toshiyuki Hosoya; Martin Miranda; Ryotaro Inoue; Mikio Kozuma

    2014-12-02T23:59:59.000Z

    We developed a high-power laser system at a wavelength of 399 nm for laser cooling of ytterbium atoms with ultraviolet laser diodes. The system is composed of an external cavity laser diode providing frequency stabilized output at a power of 40 mW and another laser diode for amplifying the laser power up to 220 mW by injection locking. The systematic method for optimization of our injection locking can also be applied to high power light sources at any other wavelengths. Our system, which does not depend on complex nonlinear frequency-doubling, has great importance for implementing transportable optical lattice clocks, and is also useful for investigations on condensed matter physics or quantum information processing using cold atoms.

  19. ECONOMIC IMPACT OF EXTREME CLIMATE EVENTS: AN APPROACH BASED ON PENULTIMATE EXTREME VALUE THEORY

    E-Print Network [OSTI]

    Katz, Richard

    .isse.ucar.edu/staff/katz/docs/pdf/jsmrwk12.pdf #12;Hurricane Andrew (1992) #12;#12;Outline (1) Motivation (2) Ultimate Extreme Value Theory (3) Penultimate Extreme Value Theory (4) Damage Functions (5) Economic Damage Caused by Hurricanes (6 assumed L V b , b > 0 (e. g., b = 3 argued on physical basis for hurricane damage as function

  20. ECONOMIC IMPACT OF EXTREME EVENTS: AN APPROACH BASED ON EXTREME VALUE THEORY

    E-Print Network [OSTI]

    Katz, Richard

    ;Hurricane Andrew (1992) #12;Outline (1) Motivation (2) Ultimate Extreme Value Theory (3) Penultimate Extreme Value Theory (4) Damage Functions (5) Economic Damage Caused by Hurricanes (6) Discussion #12 on physical basis for hurricane damage as function of intensity) #12;-- Assume stretched exponential

  1. Extreme Science (LBNL Science at the Theater)

    SciTech Connect (OSTI)

    Ajo-Franklin, Caroline; Klein, Spencer; Minor, Andrew; Torok, Tamas

    2012-02-27T23:59:59.000Z

    On Feb. 27, 2012 at the Berkeley Repertory Theatre, four Berkeley Lab scientists presented talks related to extreme science - and what it means to you. Topics include: Neutrino hunting in Antarctica. Learn why Spencer Klein goes to the ends of the Earth to search for these ghostly particles. From Chernobyl to Central Asia, Tamas Torok travels the globe to study microbial diversity in extreme environments. Andrew Minor uses the world's most advanced electron microscopes to explore materials at ultrahigh stresses and in harsh environments. And microbes that talk to computers? Caroline Ajo-Franklin is pioneering cellular-electrical connections that could help transform sunlight into fuel.

  2. Extremal structures of multiphase heat conducting composites

    E-Print Network [OSTI]

    Cherkaev, Andrej

    Extremal structures of multiphase heat conducting composites A.V. Cherkaev \\Lambda L.V. Gibiansky y April 19, 1995 Abstract In this paper we construct microstructures of multiphase composites with un be easily gen­ eralized for the three­dimensional composites with arbitrary number of phases. 1 Introduction

  3. "Extreme Project Management" One World Trade

    E-Print Network [OSTI]

    Guiltinan, Mark

    "Extreme Project Management" One World Trade Center A special presentation with a discussion of managing multiple large projects at the World Trade Center site with multiple adjacencies, complicated 1984), PE, PMP, is the Program Director for One World Trade Center. Lynda Tollner, is a Program

  4. 4, 43614387, 2007 Extreme tidal levels

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    affected by human interferences, e.g. in-channel dredging, sand mining and the construction of levees-intensive dredging. The stations along the coastal regions show significant increasing extreme high/low water level. The coastal regions are not influenced by in-channel dredging, and furthermore,20 sediment loads from upper

  5. Extremes in climate science Andreas Sterl (KNMI)

    E-Print Network [OSTI]

    Stoffelen, Ad

    (non-deterministic) influences: sun, volcanoes, anthropogenic effects (GHG emissions) => deterministic Sterl, PhysMathClim Climate change GHG concentrations increase => Temperature increases => other weather;31.01.2012, Utrecht Andreas Sterl, PhysMathClim EVT - 1 Extremes: tail of a distribution => few observations => tail

  6. ECSS in the eXtreme

    E-Print Network [OSTI]

    William O'Mullane; John Hoar; Uwe Lammers

    2007-12-03T23:59:59.000Z

    The ESAC Gaia team engages in a form of eXtreme programming while the DPAC will follow a series of six month development cycles modeled on this approach. As a project within the European Space Agency the European Committee for Space Standardization (ECSS) standards are required. We present the bringing together of these realms.

  7. Viscosity to entropy ratio at extremality

    E-Print Network [OSTI]

    Sayan K. Chakrabarti; Sachin Jain; Sudipta Mukherji

    2010-01-19T23:59:59.000Z

    Assuming gauge theory realization at the boundary, we show that the viscosity to entropy ratio is 1/(4 pi) where the bulk is represented by a large class of extremal black holes in anti-de Sitter space. In particular, this class includes multiple R-charged black holes in various dimensions.

  8. AIR CONDITIONER REQUEST EXTREME MEDICAL CIRCUMSTANCES

    E-Print Network [OSTI]

    AIR CONDITIONER REQUEST DUE TO EXTREME MEDICAL CIRCUMSTANCES TO BE COMPLETED BY ATTENDING Moderate Significant Is the use of an air conditioner desirable Yes No OR essential Yes No to the management of allergy? Is the use of an air conditioner

  9. 44 | Triennial Scientific Report Extreme rainfall climatology

    E-Print Network [OSTI]

    Stoffelen, Ad

    ,whichcan,forexample,be usedfordesignpurposesinwatermanagementorthe evaluationoftherarityofsevereweather. Radar and rain gauge data KNMIoperatestwo(MFBS). Raingaugesproducepointmeasurements,whereasradar KNMI has an archive of 11 years of radar rainfall depths for the entire land surface44 | Triennial Scientific Report Extreme rainfall climatology from weather radar Aart Overeem, Iwan

  10. Gamma Ray Burst Constraints on Ultraviolet Lorentz Invariance Violation

    E-Print Network [OSTI]

    Tina Kahniashvili; Grigol Gogoberidze; Bharat Ratra

    2006-10-20T23:59:59.000Z

    We present a unified general formalism for ultraviolet Lorentz invariance violation (LV) testing through electromagnetic wave propagation, based on both dispersion and rotation measure data. This allows for a direct comparison of the efficacy of different data to constrain LV. As an example we study the signature of LV on the rotation of the polarization plane of $\\gamma$-rays from gamma ray bursts in a LV model. Here $\\gamma$-ray polarization data can provide a strong constraint on LV, 13 orders of magnitude more restrictive than a potential constraint from the rotation of the cosmic microwave background polarization proposed by Gamboa, L\\'{o}pez-Sarri\\'{o}n, and Polychronakos (2006).

  11. The ultraviolet spectra of SO?¹? and SO?¹? near 2300 A 

    E-Print Network [OSTI]

    Kim, Sang Uk

    1966-01-01T23:59:59.000Z

    22 10 Isotope Shift of Bands in the 2300 S02 ~ 13 Vapor Pressure Curve of SO Correction Curve. A System of 24 33 INTRODUCTION SO has three absorption regions in the ultraviolet portion of its spectrum. They are located at 5900 ? 5400 A.... The emission spectrum lines of the iron arc were used as a 14 TABLE I CORRESPONDING PRESSURES AT DIFFERENT TEMPERATURES PLATL' NUMBER 3 Spectrograms Temperatures -100 C - 85'c - 70'0 - 65'c 50 C Pressures 22 mm 33 mm 43 mm 73 15 standard...

  12. Graphene/GaN diodes for ultraviolet and visible photodetectors

    SciTech Connect (OSTI)

    Lin, Fang; Chen, Shao-Wen; Meng, Jie; Tse, Geoffrey; Fu, Xue-Wen; Xu, Fu-Jun [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Shen, Bo; Liao, Zhi-Min, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn; Yu, Da-Peng, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2014-08-18T23:59:59.000Z

    The Schottky diodes based on graphene/GaN interface are fabricated and demonstrated for the dual-wavelength photodetection of ultraviolet (UV) and green lights. The physical mechanisms of the photoelectric response of the diodes with different light wavelengths are different. For UV illumination, the photo-generated carriers lower the Schottky barrier and increase the photocurrent. For green light illumination, as the photon energy is smaller than the bandgap of GaN, the hot electrons excited in graphene via internal photoemission are responsible for the photoelectric response. Using graphene as a transparent electrode, the diodes show a ?mS photoresponse, providing an alternative route toward multi-wavelength photodetectors.

  13. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOE Patents [OSTI]

    Sze, Robert C. (Santa Fe, NM); Quigley, Gerard P. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source. A contamination-free VUV light source having a 225 cm.sup.2 emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm.sup.2 at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing.

  14. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOE Patents [OSTI]

    Sze, R.C.; Quigley, G.P.

    1996-12-17T23:59:59.000Z

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source is disclosed. A contamination-free VUV light source having a 225 cm{sup 2} emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm{sup 2} at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing. 3 figs.

  15. The ultraviolet spectra of SO?¹? and SO?¹? near 2300 A

    E-Print Network [OSTI]

    Kim, Sang Uk

    1966-01-01T23:59:59.000Z

    22 10 Isotope Shift of Bands in the 2300 S02 ~ 13 Vapor Pressure Curve of SO Correction Curve. A System of 24 33 INTRODUCTION SO has three absorption regions in the ultraviolet portion of its spectrum. They are located at 5900 ? 5400 A.... The emission spectrum lines of the iron arc were used as a 14 TABLE I CORRESPONDING PRESSURES AT DIFFERENT TEMPERATURES PLATL' NUMBER 3 Spectrograms Temperatures -100 C - 85'c - 70'0 - 65'c 50 C Pressures 22 mm 33 mm 43 mm 73 15 standard...

  16. Ultraviolet Absorber UV-770 Market | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin Baxin HydropowerTrinityTurnbullGlobalUbbinkUkrainianUltraviolet

  17. Accident Investigations

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2011-03-04T23:59:59.000Z

    This Order prescribes organizational responsibilities, authorities, and requirements for conducting investigations of certain accidents occurring at DOE sites, facilities, areas, operations, and activities.

  18. Hidden conformal symmetry of extreme and non-extreme Einstein-Maxwell-Dilaton-Axion black holes

    E-Print Network [OSTI]

    Deyou Chen; Hui Wang; Houwen Wu; Haitang Yang

    2010-10-19T23:59:59.000Z

    The hidden conformal symmetry of extreme and non-extreme Einstein-Maxwell-Dilaton-Axion (EMDA) black holes is addressed in this paper. For the non-extreme one, employing the wave equation of massless scalars, the conformal symmetry with left temperature $T_{L}=\\frac{M}{2\\pi a}$ and right temperature $T_{R}=\\frac{\\sqrt{M^{2}-a^{2}}}{2\\pi a}$ in the near region is found. The conformal symmetry is spontaneously broken due to the periodicity of the azimuthal angle. The microscopic entropy is derived by the Cardy formula and is fully in consistence with the Bekenstein-Hawking area-entropy law. The absorption cross section in the near region is calculated and exactly equals that in a 2D CFT. For the extreme case, by redefining the conformal coordinates, the duality between the solution space and CFT is studied. The microscopic entropy is found to exactly agree with the area-entropy law.

  19. Ultraviolet Germicidal Irradiation and Its Effects on Elemental Distributions in Mouse Embryonic Fibroblast Cells in X-Ray Fluorescence Microanalysis

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

    Jin, Qiaoling; Vogt, Stefan; Lai, Barry; Chen, Si; Finney, Lydia; Gleber, Sophie-Charlotte; Ward, Jesse; Deng, Junjing; Mak, Rachel; Moonier, Nena; et al

    2015-02-23T23:59:59.000Z

    Rapidly-frozen hydrated (cryopreserved) specimens combined with cryo-scanning x-ray fluorescence microscopy provide an ideal approach for investigating elemental distributions in biological cells and tissues. However, because cryopreservation does not deactivate potentially infectious agents associated with Risk Group 2 biological materials, one must be concerned with contamination of expensive and complicated cryogenic x-ray microscopes when working with such materials. We employed ultraviolet germicidal irradiation to decontaminate previously cryopreserved cells under liquid nitrogen, and then investigated its effects on elemental distributions under both frozen hydrated and freeze dried states with xray fluorescence microscopy. We show that the contents and distributions of most biologicallymore »important elements remain nearly unchanged when compared with non-ultravioletirradiated counterparts, even after multiple cycles of ultraviolet germicidal irradiation and cryogenic x-ray imaging. This provides a potential pathway for rendering Risk Group 2 biological materials safe for handling in multiuser cryogenic x-ray microscopes without affecting the fidelity of the results.« less

  20. PITTING CORROSION ON MAGNESIUM ALLOYS : A COMPARATIVE STUDY OF FIELD DATA USING EXTREME VALUE

    E-Print Network [OSTI]

    Maume-Deschamps, Véronique

    PITTING CORROSION ON MAGNESIUM ALLOYS : A COMPARATIVE STUDY OF FIELD DATA USING EXTREME VALUE corrosion of the magnesium alloys AZ91D and AM60B combined with different coatings on steel bolts was investigated in field corrosion tests carried out by Volvo Car Corporation. Light metals like magnesium

  1. Ultraviolet Free Electron Laser Facility preliminary design report

    SciTech Connect (OSTI)

    Ben-Zvi, I. [ed.

    1993-02-01T23:59:59.000Z

    This document, the Preliminary Design Report (PDR) for the Brookhaven Ultraviolet Free Electron Laser (UV FEL) facility, describes all the elements of a facility proposed to meet the needs of a research community which requires ultraviolet sources not currently available as laboratory based lasers. Further, for these experiments, the requisite properties are not extant in either the existing second or upcoming third generation synchrotron light sources. This document is the result of our effort at BNL to identify potential users, determine the requirements of their experiments, and to design a facility which can not only satisfy the existing need, but have adequate flexibility for possible future extensions as need dictates and as evolving technology allows. The PDR is comprised of three volumes. In this, the first volume, background for the development of the proposal is given, including descriptions of the UV FEL facility, and representative examples of the science it was designed to perform. Discussion of the limitations and potential directions for growth are also included. A detailed description of the facility design is then provided, which addresses the accelerator, optical, and experimental systems. Information regarding the conventional construction for the facility is contained in an addendum to volume one (IA).

  2. Transporting container for an amputated extremity

    SciTech Connect (OSTI)

    Ammerman, S.W.

    1988-02-09T23:59:59.000Z

    A container assembly for transporting of an amputated extremity to a location for replantation is described comprising: an inner compartment adapted to receive an amputated extremity, the inner compartment being defined by a wall, an access opening providing access into the inner compartment, the access opening being closable; a completely closed outer compartment surrounding the inner compartment, the outer compartment abutting the wall; and cooling bags located within the outer compartment, Each cooling bag contains a pair of substances when mixed results in the production of a cooling affect. Each cooling bag contains chambers. The chambers are connected but separate. One of the substances is a granulized solid. The granulized solid is located within the separate chambers, whereby upon mixing occurring of the substances substantially even distribution of the cooling affect is obtained across the entire width of the inner compartment due to mixing between the substances occurring within each chamber.

  3. Ambient Levels of Ultraviolet-B Radiation Cause Mortality in Juvenile Western Toads, Bufo boreas

    E-Print Network [OSTI]

    Blaustein, Andrew R.

    Ambient Levels of Ultraviolet-B Radiation Cause Mortality in Juvenile Western Toads, Bufo boreas industrial gases contribute to the depletion of the earth's protective ozone layer, resulting in increased amounts of cell damaging ultraviolet-B (UV-B) radiation reaching the surface of the earth. Recent

  4. Author's personal copy Effects of ultraviolet radiation on an intertidal trematode parasite: An assessment

    E-Print Network [OSTI]

    Poulin, Robert

    Author's personal copy Effects of ultraviolet radiation on an intertidal trematode parasite: An assessment of damage and protection A. Studer a, , V.M. Cubillos b,c , M.D. Lamare c , R. Poulin a , D ecosystems which experience high levels of ultraviolet radiation. Although these parasites mostly live within

  5. Hubble Space Telescope FOS Optical and Ultraviolet Spectroscopy of the Bow Shock HH 47A 1

    E-Print Network [OSTI]

    Hartigan, Patrick

    Hubble Space Telescope FOS Optical and Ultraviolet Spectroscopy of the Bow Shock HH 47A 1 Patrick Telescope of the HH 47A bow shock and Mach disk that cover the entire spectral range between 2220 Å¡ that the Fe II line broadening must exceed that expected from thermal motions. Excitation of ultraviolet Fe II

  6. Chiral gravity, log gravity, and extremal CFT

    SciTech Connect (OSTI)

    Maloney, Alexander [Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada); Song Wei [Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190 (China); Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States); Strominger, Andrew [Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States)

    2010-03-15T23:59:59.000Z

    We show that the linearization of all exact solutions of classical chiral gravity around the AdS{sub 3} vacuum have positive energy. Nonchiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity--the theory with logarithmically relaxed boundary conditions--has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic conformal field theories (CFT). Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We formally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

  7. Development of an Extreme Environment Materials Research Facility at Princeton

    SciTech Connect (OSTI)

    Cohen, A B; Tully, C G; Austin, R; Calaprice, F; McDonald, K; Ascione, G; Baker, G; Davidson, R; Dudek, L; Grisham, L; Kugel, H; Pagdon, K; Stevenson, T; Woolley, R

    2010-11-17T23:59:59.000Z

    The need for a fundamental understanding of material response to a neutron and/or high heat flux environment can yield development of improved materials and operations with existing materials. Such understanding has numerous applications in fields such as nuclear power (for the current fleet and future fission and fusion reactors), aerospace, and other research fields (e.g., high-intensity proton accelerator facilities for high energy physics research). A proposal has been advanced to develop a facility for testing various materials under extreme heat and neutron exposure conditions at Princeton. The Extreme Environment Materials Research Facility comprises an environmentally controlled chamber (48 m^3) capable of high vacuum conditions, with extreme flux beams and probe beams accessing a central, large volume target. The facility will have the capability to expose large surface areas (1 m^2) to 14 MeV neutrons at a fluence in excess of 10^13 n/s. Depending on the operating mode. Additionally beam line power on the order of 15-75 MW/m2 for durations of 1-15 seconds are planned... The multi-second duration of exposure can be repeated every 2-10 minutes for periods of 10-12 hours. The facility will be housed in the test cell that held the Tokamak Fusion Test Reactor (TFTR), which has the desired radiation and safety controls as well as the necessary loading and assembly infrastructure. The facility will allow testing of various materials to their physical limit of thermal endurance and allow for exploring the interplay between radiation-induced embrittlement, swelling and deformation of materials, and the fatigue and fracturing that occur in response to thermal shocks. The combination of high neutron energies and intense fluences will enable accelerated time scale studies. The results will make contributions for refining predictive failure modes (modeling) in extreme environments, as well as providing a technical platform for the development of new alloys, new materials, and the investigation of repair mechanisms. Effects on materials will be analyzed with in situ beam probes and instrumentation as the target is exposed to radiation, thermal fluxes and other stresses. Photon and monochromatic neutron fluxes, produced using a variable-energy (4-45 MeV) electron linac and the highly asymmetric electron-positron collisions technique used in high-energy physics research, can provide non-destructive, deep-penetrating structural analysis of materials while they are undergoing testing. The same beam lines will also be able to generate neutrons from photonuclear interactions using existing Bremsstrahlung and positrons on target quasi-monochromatic gamma rays. Other diagnostics will include infrared cameras, residual gas analyzer (RGA), and thermocouples; additional diagnostic capability will be added.

  8. Fitting In: Extreme Corporate Wellness and Organizational Communication

    E-Print Network [OSTI]

    James, Eric Preston

    2014-07-31T23:59:59.000Z

    In this dissertation I examine the intersection of organizational communication and what I name extreme corporate wellness. I define extreme corporate wellness as the push towards more radical fitness and workplace health promotion via the exercise...

  9. The effects of orthotics on lower extremity variability during running

    E-Print Network [OSTI]

    Brethauer, Samuel

    2011-12-31T23:59:59.000Z

    Introduction: Abnormal foot mechanics may affect kinematics of the lower extremity, predisposing individuals to injury. Foot orthotics are often used to alter lower extremity mechanics. Little research is available examining ...

  10. Great Lakes Water Level Statistics Primary Investigator: Cynthia Sellinger

    E-Print Network [OSTI]

    Great Lakes Water Level Statistics Primary Investigator: Cynthia Sellinger Overview Extreme Great disruption throughout the Great Lakes system. Reliable lake level frequency distributions are a critical of monthly lake levels reflect secular changes in connecting channel hydraulics, watershed hydrologic

  11. Method for detection of extremely low concentration

    DOE Patents [OSTI]

    Andresen, Brian D. (Livermore, CA); Miller, Fred S. (Bethal Island, CA)

    2002-01-01T23:59:59.000Z

    An ultratrace detector system for hand-held gas chromatography having high sensitivity, for example, to emissions generated during production of weapons, biological compounds, drugs, etc. The detector system is insensitive to water, air, helium, argon, oxygen, and CO.sub.2. The detector system is basically composed of a hand-held capillary gas chromatography (GC), an insulated heated redox-chamber, a detection chamber, and a vapor trap. For example, the detector system may use gas phase redox reactions and spectral absorption of mercury vapor. The gas chromatograph initially separates compounds that percolate through a bed of heated mercuric oxide (HgO) in a silica--or other metal--aerogel material which acts as an insulator. Compounds easily oxidized by HgO liberate atomic mercury that subsequently pass through a detection chamber which includes a detector cell, such as quartz, that is illuminated with a 254 nm ultra-violet (UV) mercury discharge lamp which generates the exact mercury absorption bands that are used to detect the liberated mercury atoms. Atomic mercury strongly absorbs 254 nm energy is therefore a specific signal for reducing compounds eluting from the capillary GC, whereafter the atomic mercury is trapped for example, in a silicon-aerogel trap.

  12. The New Palgrave Dictionary of Economics Online extreme poverty

    E-Print Network [OSTI]

    The New Palgrave Dictionary of Economics Online extreme poverty Jeffrey D. Sachs and Gordon C. Mc://www.dictionaryofeconomics.com/article?id=pde2008_E000293 Abstract Households living in extreme poverty face deprivations that cost millions of lives annually. Ending extreme poverty requires an understanding of poverty traps, including the effects

  13. STATISTICS OF PRECIPITATION EXTREMES: QUANTIFYING CONFIDENCE IN TRENDS

    E-Print Network [OSTI]

    Katz, Richard

    this situation (e. g., "extRemes" package in open source statistical programming language R) Maximum likelihood1 STATISTICS OF PRECIPITATION EXTREMES: QUANTIFYING CONFIDENCE IN TRENDS Rick Katz Institute in Causes of Trends #12;4 (1) Introduction · Extreme value analysis under stationarity -- Statistical theory

  14. Tunnel-injection quantum dot deep-ultraviolet light-emitting diodes with polarization-induced doping in III-nitride heterostructures

    SciTech Connect (OSTI)

    Verma, Jai, E-mail: jverma@nd.edu; Islam, S. M.; Protasenko, Vladimir; Kumar Kandaswamy, Prem; Xing, Huili; Jena, Debdeep [Department of Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

    2014-01-13T23:59:59.000Z

    Efficient semiconductor optical emitters in the deep-ultraviolet spectral window are encountering some of the most deep rooted problems of semiconductor physics. In III-Nitride heterostructures, obtaining short-wavelength photon emission requires the use of wide bandgap high Al composition AlGaN active regions. High conductivity electron (n-) and hole (p-) injection layers of even higher bandgaps are necessary for electrical carrier injection. This approach requires the activation of very deep dopants in very wide bandgap semiconductors, which is a difficult task. In this work, an approach is proposed and experimentally demonstrated to counter the challenges. The active region of the heterostructure light emitting diode uses ultrasmall epitaxially grown GaN quantum dots. Remarkably, the optical emission energy from GaN is pushed from 365?nm (3.4?eV, the bulk bandgap) to below 240?nm (>5.2?eV) because of extreme quantum confinement in the dots. This is possible because of the peculiar bandstructure and band alignments in the GaN/AlN system. This active region design crucially enables two further innovations for efficient carrier injection: Tunnel injection of carriers and polarization-induced p-type doping. The combination of these three advances results in major boosts in electroluminescence in deep-ultraviolet light emitting diodes and lays the groundwork for electrically pumped short-wavelength lasers.

  15. Standoff ultraviolet raman scattering detection of trace levels of explosives.

    SciTech Connect (OSTI)

    Kulp, Thomas J.; Bisson, Scott E.; Reichardt, Thomas A.

    2011-10-01T23:59:59.000Z

    Ultraviolet (UV) Raman scattering with a 244-nm laser is evaluated for standoff detection of explosive compounds. The measured Raman scattering albedo is incorporated into a performance model that focused on standoff detection of trace levels of explosives. This model shows that detection at {approx}100 m would likely require tens of seconds, discouraging application at such ranges, and prohibiting search-mode detection, while leaving open the possibility of short-range point-and-stare detection. UV Raman spectra are also acquired for a number of anticipated background surfaces: tile, concrete, aluminum, cloth, and two different car paints (black and silver). While these spectra contained features in the same spectral range as those for TNT, we do not observe any spectra similar to that of TNT.

  16. Strong Ultraviolet Pulse From a Newborn Type Ia Supernova

    E-Print Network [OSTI]

    Cao, Yi; Howell, D Andrew; Gal-Yam, Avishay; Kasliwal, Mansi M; Valenti, Stefano; Johansson, J; Amanullah, R; Goobar, A; Sollerman, J; Taddia, F; Horesh, Assaf; Sagiv, Ilan; Cenko, S Bradley; Nugent, Peter E; Arcavi, Iair; Surace, Jason; Wo?niak, P R; Moody, Daniela I; Rebbapragada, Umaa D; Bue, Brian D; Gehrels, Neil

    2015-01-01T23:59:59.000Z

    Type Ia supernovae are destructive explosions of carbon oxygen white dwarfs. Although they are used empirically to measure cosmological distances, the nature of their progenitors remains mysterious, One of the leading progenitor models, called the single degenerate channel, hypothesizes that a white dwarf accretes matter from a companion star and the resulting increase in its central pressure and temperature ignites thermonuclear explosion. Here we report observations of strong but declining ultraviolet emission from a Type Ia supernova within four days of its explosion. This emission is consistent with theoretical expectations of collision between material ejected by the supernova and a companion star, and therefore provides evidence that some Type Ia supernovae arise from the single degenerate channel.

  17. Laser plasma formation assisted by ultraviolet pre-ionization

    SciTech Connect (OSTI)

    Yalin, Azer P., E-mail: ayalin@engr.colostate.edu; Dumitrache, Ciprian [Department of Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80523 (United States); Wilvert, Nick [Sandia Laboratory, Albuquerque, New Mexico 87123 (United States); Joshi, Sachin [Cummins Inc., Columbus, Indiana 47201 (United States); Shneider, Mikhail N. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

    2014-10-15T23:59:59.000Z

    We present experimental and modeling studies of air pre-ionization using ultraviolet (UV) laser pulses and its effect on laser breakdown of an overlapped near-infrared (NIR) pulse. Experimental studies are conducted with a 266?nm beam (fourth harmonic of Nd:YAG) for UV pre-ionization and an overlapped 1064?nm NIR beam (fundamental of Nd:YAG), both having pulse duration of ?10?ns. Results show that the UV beam produces a pre-ionized volume which assists in breakdown of the NIR beam, leading to reduction in NIR breakdown threshold by factor of >2. Numerical modeling is performed to examine the ionization and breakdown of both beams. The modeled breakdown threshold of the NIR, including assist by pre-ionization, is in reasonable agreement with the experimental results.

  18. Ultraviolet photoluminescence from Gd-implanted AlN epilayers

    SciTech Connect (OSTI)

    Zavada, J. M.; Nepal, N.; Lin, J. Y.; Jiang, H. X.; Brown, E.; Hoemmerich, U.; Hite, J.; Thaler, G. T.; Abernathy, C. R.; Pearton, S. J.; Gwilliam, R. [U.S. Army Research Office, Durham, North Carolina 27709 (United States); Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601 (United States); Department of Physics, Hampton University, Hampton, Virginia 23668 (United States); Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Surrey Ion Beam Center, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

    2006-10-09T23:59:59.000Z

    Deep ultraviolet emission from gadolinium (Gd)-implanted AlN thin films has been observed using photoluminescence (PL) spectroscopy. The AlN epilayers were ion implanted with Gd to a total dose of {approx}6x10{sup 14} cm{sup -2}. Using the output at 197 nm from a quadrupled Ti:sapphire laser, narrow PL emission was observed at 318 nm, characteristic of the trivalent Gd ion. A broader emission band, also centered at 318 nm, was measured with excitation at 263 nm. The PL emission intensity decreased by less than a factor of 3 over the sample temperature range of 10-300 K and decay transients were of the order of nanoseconds.

  19. Mesoscale Predictability of an Extreme Warm-Season Precipitation Event FUQING ZHANG, ANDREW M. ODINS, AND JOHN W. NIELSEN-GAMMON

    E-Print Network [OSTI]

    Mesoscale Predictability of an Extreme Warm-Season Precipitation Event FUQING ZHANG, ANDREW M Station, Texas (Manuscript received 22 November 2004, in final form 28 August 2005) ABSTRACT A mesoscale model is used to investigate the mesoscale predictability of an extreme precipitation event over central

  20. Radiation stability of graphene under extreme conditions

    SciTech Connect (OSTI)

    Kumar, Sunil, E-mail: kumar.sunil092@gmail.com; Tripathi, Ambuj; Khan, Saif A.; Pannu, Compesh; Avasthi, Devesh K. [Materials Science Group, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

    2014-09-29T23:59:59.000Z

    In this letter, we report radiation stability of graphene under extreme condition of high energy density generated by 150?MeV Au ion irradiation. The experiment reveals that graphene is radiation resistant for irradiation at 10{sup 14?}ions/cm{sup 2} of 150?MeV Au ions. It is significant to note that annealing effects are observed at lower fluences whereas defect production occurs at higher fluences but significant crystallinity is retained. Our results demonstrate applicability of graphene based devices in radiation environment and space applications.

  1. Ultrahigh Energy Neutrals from Extreme Magnetic Flares

    E-Print Network [OSTI]

    David Eichler

    2003-03-20T23:59:59.000Z

    It is shown that bulk acceleration during reconnection of extremely strong magnetic fields near compact objects can accelerate ions to Lorentz factors of $\\sim 10^2 \\sigma^{3/5}$ under general conditions, where $\\sigma$, the magnetic energy per current-carrying proton rest energy, can approach $10^{15}$. For magnetar-type fields, neutrons and neutrinos can be generated at potentially detectable levels via hadron polarization. Ultrahigh energy photons can also be emitted and escorted from the high field region by Poynting flux.

  2. Extremely compliant and highly stretchable patterned graphene

    SciTech Connect (OSTI)

    Zhu, Shuze; Huang, Yinjun; Li, Teng, E-mail: LiT@umd.edu [Department of Mechanical Engineering and Maryland NanoCenter, University of Maryland, College Park, Maryland 20742 (United States)

    2014-04-28T23:59:59.000Z

    Graphene is intrinsically ultra-stiff in its plane. Its huge mechanical mismatch when interfacing with ultra-compliant biological tissues and elastomers (7–9 orders of magnitude difference in stiffness) poses significant challenge in its application to functional devices such as epidermal electronics and sensing prosthesis. We offer a feasible and promising solution to this significant challenge by suitably patterning graphene into a nanomesh. Through systematic coarse-grained simulations, we show that graphene nanomesh can be made extremely compliant with nearly zero stiffness up to about 20% elongation and then remain highly compliant up to about 50% elongation.

  3. Chaotic Information Processing by Extremal Black Holes

    E-Print Network [OSTI]

    Axenides, Minos; Nicolis, Stam

    2015-01-01T23:59:59.000Z

    We review an explicit regularization of the AdS$_2$/CFT$_1$ correspondence, that preserves all isometries of bulk and boundary degrees of freedom. This scheme is useful to characterize the space of the unitary evolution operators that describe the dynamics of the microstates of extremal black holes in four spacetime dimensions. Using techniques from algebraic number theory to evaluate the transition amplitudes, we remark that the regularization scheme expresses the fast quantum computation capability of black holes as well as its chaotic nature.

  4. Extremely Low Temperature | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model,DOEHazelPennsylvania: EnergyExolis Energy Jump to:AnalogsOpenExtremely Low

  5. Extreme Scale Computing, Co-design

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. Category UC-l 1,EnergyExploringGamma-ray AttenuationExtreme Scale

  6. Accident Investigations

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1996-04-26T23:59:59.000Z

    To prescribe requirements for conducting investigations of certain accidents occurring at Department of Energy (DOE) operations and sites; to improve the environment, safety and health for DOE, contractors, and the public; and to prevent the recurrence of such accidents. Chg 2, 4-26-96

  7. Accident Investigations

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1995-10-26T23:59:59.000Z

    To prescribe requirements for conducting investigations of certain accidents occurring at Department of Energy (DOE) operations and sites; to improve the environment , safety and health for DOE, contractors, and the public; and to prevent the recurrence of such accidents. Chg 1, 10-26-95. Cancels parts of DOE 5484.1

  8. Matter-radiation interactions in extremes

    SciTech Connect (OSTI)

    Garnett, Robert W [Los Alamos National Laboratory; Gulley, Mark S [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    LANSCE has been the centerpiece of large-scale science at Los Alamos National Laboratory for many decades. Recently, funding has been obtained to ensure continued reliable operation of the LANSCE linac and to allow planning to enable the first in a new generation of scientific facilities for the materials community. The emphasis of this new facility is 'Matter-Radiation Interactions in Extremes' (MaRIE) which will be used to discover and design the advanced materials needed to meet 21st century national security and energy security challenges. MaRIE will provide the tools scientists need to develop next-generation materials that will perform predictably and on-demand for currently unattainable lifetimes in extreme environments. The MaRIE facility is based on a high-power upgrade to the existing LANSCE proton linac, a new electron linac and associated X-ray FEL to provide additional probe beams, and new experimental areas. A conceptual description of this new facility and its requirements will be presented.

  9. Method and apparatus for producing durationally short ultraviolet or X-ray laser pulses

    DOE Patents [OSTI]

    MacGowan, Brian J. (Livermore, CA); Matthews, Dennis L. (El Granada, CA); Trebes, James E. (Livermore, CA)

    1988-01-01T23:59:59.000Z

    A method and apparatus is disclosed for producing ultraviolet or X-ray laser pulses of short duration (32). An ultraviolet or X-ray laser pulse of long duration (12) is progressively refracted, across the surface of an opaque barrier (28), by a streaming plasma (22) that is produced by illuminating a solid target (16, 18) with a pulse of conventional line focused high power laser radiation (20). The short pulse of ultraviolet or X-ray laser radiation (32), which may be amplified to high power (40, 42), is separated out by passage through a slit aperture (30) in the opaque barrier (28).

  10. Method and apparatus for producing durationally short ultraviolet or x-ray laser pulses

    DOE Patents [OSTI]

    MacGowan, B.J.; Matthews, D.L.; Trebes, J.E.

    1987-05-05T23:59:59.000Z

    A method and apparatus is disclosed for producing ultraviolet or x- ray laser pulses of short duration. An ultraviolet or x-ray laser pulse of long duration is progressively refracted, across the surface of an opaque barrier, by a streaming plasma that is produced by illuminating a solid target with a pulse of conventional line focused high power laser radiation. The short pulse of ultraviolet or x-ray laser radiation, which may be amplified to high power, is separated out by passage through a slit aperture in the opaque barrier.

  11. Vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters

    SciTech Connect (OSTI)

    Ahmed, Musahid; Ahmed, Musahid; Wilson, Kevin R.; Belau, Leonid; Kostko, Oleg

    2008-05-12T23:59:59.000Z

    In this work we report on thevacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters. Clusters of methanol with water are generated via co-expansion of the gas phase constituents in a continuous supersonic jet expansion of methanol and water seeded in Ar. The resulting clusters are investigated by single photon ionization with tunable vacuumultraviolet synchrotron radiation and mass analyzed using reflectron mass spectrometry. Protonated methanol clusters of the form (CH3OH)nH + (n=1-12) dominate the mass spectrum below the ionization energy of the methanol monomer. With an increase in water concentration, small amounts of mixed clusters of the form (CH3OH)n(H2O)H + (n=2-11) are detected. The only unprotonated species observed in this work are the methanol monomer and dimer. Appearance energies are obtained from the photoionization efficiency (PIE) curves for CH3OH +, (CH 3OH)2 +, (CH3OH)nH + (n=1-9), and (CH 3OH)n(H2O)H + (n=2-9 ) as a function of photon energy. With an increase in the water content in the molecular beam, there is an enhancement of photoionization intensity for methanol dimer and protonated methanol monomer at threshold. These results are compared and contrasted to previous experimental observations.

  12. Norathyriol Suppresses Skin Cancers Induced by Solar Ultraviolet Radiation by Targeting ERK Kinases

    SciTech Connect (OSTI)

    Li, Jixia; Malakhova, Margarita; Mottamal, Madhusoodanan; Reddy, Kanamata; Kurinov, Igor; Carper, Andria; Langfald, Alyssa; Oi, Naomi; Kim, Myoung Ok; Zhu, Feng; Sosa, Carlos P.; Zhou, Keyuan; Bode, Ann M.; Dong, Zigang (Cornell); (Guangdong); (UMM)

    2012-06-27T23:59:59.000Z

    Ultraviolet (UV) irradiation is the leading factor in the development of skin cancer, prompting great interest in chemopreventive agents for this disease. In this study, we report the discovery of norathyriol, a plant-derived chemopreventive compound identified through an in silico virtual screening of the Chinese Medicine Library. Norathyriol is a metabolite of mangiferin found in mango, Hypericum elegans, and Tripterospermum lanceolatum and is known to have anticancer activity. Mechanistic investigations determined that norathyriol acted as an inhibitor of extracellular signal-regulated kinase (ERK)1/2 activity to attenuate UVB-induced phosphorylation in mitogen-activated protein kinases signaling cascades. We confirmed the direct and specific binding of norathyriol with ERK2 through a cocrystal structural analysis. The xanthone moiety in norathyriol acted as an adenine mimetic to anchor the compound by hydrogen bonds to the hinge region of the protein ATP-binding site on ERK2. Norathyriol inhibited in vitro cell growth in mouse skin epidermal JB6 P+ cells at the level of G{sub 2}-M phase arrest. In mouse skin tumorigenesis assays, norathyriol significantly suppressed solar UV-induced skin carcinogenesis. Further analysis indicated that norathyriol mediates its chemopreventive activity by inhibiting the ERK-dependent activity of transcriptional factors AP-1 and NF-{kappa}B during UV-induced skin carcinogenesis. Taken together, our results identify norathyriol as a safe new chemopreventive agent that is highly effective against development of UV-induced skin cancer.

  13. Non-extremal fuzzballs and ergoregion emission

    E-Print Network [OSTI]

    Borun D. Chowdhury; Samir D. Mathur

    2008-10-23T23:59:59.000Z

    In the traditional picture of black holes Hawking radiation is created by pair creation from the vacuum at the horizon. In the fuzzball proposal, individual microstates do not have a horizon with the `vacuum' state in its vicinity. For a special family of non-extremal microstates it was recently found that emission occurs due to pair creation in an ergoregion, rather than at a horizon. In this paper we extend this result to a slightly larger class of microstates, again finding exact agreement between the emission in the gravity picture and the CFT dual. We write down an expression for emission from geometries with ergoregions, in terms of the leading falloff behavior of the wavefunctions in the fuzzball region. Finally, we describe another family of nonextremal microstates and find their ergoregion.

  14. Matter Under Extreme Conditions: The Early Years

    E-Print Network [OSTI]

    Keeler, R Norris

    2010-01-01T23:59:59.000Z

    Extreme conditions in natural flows are examined, starting with a turbulent big bang. A hydro-gravitational-dynamics cosmology model is adopted. Planck-Kerr turbulence instability causes Planck-particle turbulent combustion. Inertial-vortex forces induce a non-turbulent kinetic energy cascade to Planck-Kolmogorov scales where vorticity is produced, overcoming 10^113 Pa Planck-Fortov pressures. The spinning, expanding fireball has a slight deficit of Planck antiparticles. Space and mass-energy powered by gluon viscous stresses expand exponentially at speeds >10^25 c. Turbulent temperature and spin fluctuations fossilize at scales larger than ct, where c is light speed and t is time. Because â??dark-energyâ? antigravity forces vanish when inflation ceases, and because turbulence produces entropy, the universe is closed and will collapse and rebound. Density and spin fossils of big bang turbulent mixing trigger structure formation in the plasma epoch. Fragmenting protosuperclustervoids and protoclustervoi...

  15. A Road Map to Extreme High Vacuum

    SciTech Connect (OSTI)

    Ganapati Rao Myneni

    2007-06-20T23:59:59.000Z

    Ultimate pressure of a well-designed vacuum system very much depends on pretreatments, processing and the procedures [1,2]. Until now much attention has been paid in minimizing hydrogen outgassing from the chamber material. However, procedures and processing deserves further scrutiny than hitherto given so far. For reducing the gas load, high sensitivity helium leak detection techniques with sensitivities better than 1× 10-12 Torr l/sec need to be used. Effects that are induced by vacuum instrumentation need to be reduced in order to obtain accurate pressure measurements. This presentation will discuss: clean assembly procedures, metal sponges for cryosorption pumping of hydrogen to extreme high vacuum, low cost surface diffusion barriers for reducing the hydrogen gas load, cascade pumping, sensitive helium leak detection techniques and the use of modified extractor and residual gas analyzers. Further, alternative back up pumping systems based on active NEG’s [3] for turbo molecular pumps will be presented.

  16. The development and application of a diode-laser-based ultraviolet absorption sensor for nitric oxide 

    E-Print Network [OSTI]

    Anderson, Thomas Nathan

    2004-09-30T23:59:59.000Z

    This thesis describes the development of a new type of sensor for nitric oxide (NO) that can be used in a variety of combustion diagnostics and control applications. The sensor utilizes the absorption of ultraviolet (UV) ...

  17. Tryptophan Cluster Protects Human ?D-Crystallin from Ultraviolet Radiation-Induced Photoaggregation

    E-Print Network [OSTI]

    Schafheimer, Steven Nathaniel

    Exposure to ultraviolet radiation (UVR) is a significant risk factor for age-related cataract, a disease of the human lens and the most prevalent cause of blindness in the world. Cataract pathology involves protein misfolding ...

  18. Quantum Field Theory on Noncommutative Space-Times and the Persistence of Ultraviolet Divergences

    E-Print Network [OSTI]

    M. Chaichian; A. Demichev; P. Presnajder

    1999-04-13T23:59:59.000Z

    We study properties of a scalar quantum field theory on two-dimensional noncommutative space-times. Contrary to the common belief that noncommutativity of space-time would be a key to remove the ultraviolet divergences, we show that field theories on a noncommutative plane with the most natural Heisenberg-like commutation relations among coordinates or even on a noncommutative quantum plane with $E_q(2)$-symmetry have ultraviolet divergences, while the theory on a noncommutative cylinder is ultraviolet finite. Thus, ultraviolet behaviour of a field theory on noncommutative spaces is sensitive to the topology of the space-time, namely to its compactness. We present general arguments for the case of higher space-time dimensions and as well discuss the symmetry transformations of physical states on noncommutative space-times.

  19. EVIDENCE FOR TYPE Ia SUPERNOVA DIVERSITY FROM ULTRAVIOLET OBSERVATIONS WITH THE HUBBLE SPACE TELESCOPE

    E-Print Network [OSTI]

    Lewin, Walter H. G.

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This ...

  20. The O iv and S iv intercombination lines in the ultraviolet spectra of astrophysical sources

    E-Print Network [OSTI]

    , obtained with the Solar Ultraviolet Measurements of the Emitted Radiation (sumer) instrument on the Solar/09/2002; 9:46; p.1 #12; 2 Keenan et al. line ratios and observational data. For example, Cook et al. (1995

  1. Solar ultraviolet-B radiation and vitamin D: a cross-sectional population-based

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Solar ultraviolet-B radiation and vitamin D: a cross-sectional population-based study using data,3* Abstract Background: Exposure to solar ultraviolet-B (UV-B) radiation is a major source of vitamin D3AUR 17326E125C4(7E3E3C7E>4(72B43.EE7D4" 7D4":BE27B725CE9393BE647 #12;RESEARCH ARTICLE Open Access Solar

  2. Microbial Reduction on Eggshell Surfaces by the use of Hydrogen Peroxide and Ultraviolet Light

    E-Print Network [OSTI]

    Gottselig, Steven Michael

    2011-10-21T23:59:59.000Z

    MICROBIAL REDUCTION ON EGGSHELL SURFACES BY THE USE OF HYDROGEN PEROXIDE AND ULTRAVIOLET LIGHT A Thesis by STEVEN MICHAEL GOTTSELIG Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 2011 Major Subject: Poultry Science Microbial Reduction on Eggshell Surfaces by the Use of Hydrogen Peroxide and Ultraviolet Light Copyright 2011...

  3. Ultraviolet light absorbers having two different chromophors in the same molecule

    DOE Patents [OSTI]

    Vogl, O.; Li, S.

    1983-10-06T23:59:59.000Z

    This invention relates to novel ultraviolet light absorbers having two chromophors in the same molecule, and more particularly to benzotriazole substituted dihydroxybenzophenones and acetophenones. More particularly, this invention relates to 3,5-(di(2H-benzotriazole-2-yl))-2,4-dihydroxybenzophenone and 3,5-(di(2H-benzotriazole-2-yl))-2,4-dihydroxyacetophenone which are particularly useful as an ultraviolet light absorbers.

  4. Gas-phase ultraviolet photoelectron spectroscopy and molecular orbital calculations on transition metal carbonyls and nitrosyls

    E-Print Network [OSTI]

    Morris-Sherwood, Betty Jeanne

    1981-01-01T23:59:59.000Z

    GAS-PHASE ULTRAVIOLET PHOTOELECTRON SPECTROSCOPY AND MOLECULAR ORBITAL CALCULATIONS ON TRANSITION METAL CARBONYLS AND NITROSYLS A Thesis by BETTY JEANNE MORRIS-SHERWOOD Submitted to the Graduate College of Texas ARM Uni ver s i ty in partial... JEANNE MORRIS-SHERWOOD Approved as to sty1e and content by: (Chairman of Committee) (Member): (Niember) r / )g (Head of Department) December 1981 ABSTRACT Gas-Phas Ultraviolet Photoelectron Spectroscopy and Molecular Orbital Calculations...

  5. The Far-Ultraviolet Ups and Downs of Alpha Centauri

    E-Print Network [OSTI]

    Ayres, Thomas R

    2014-01-01T23:59:59.000Z

    Four years (2010-2014) of semiannual pointings by Hubble Space Telescope Imaging Spectrograph (STIS) on nearby Alpha Centauri have yielded a detailed time history of far-ultraviolet emissions of the solar-like primary (A: G2V) and the cooler, but more active, secondary (B: K1V). This period saw A climbing out of a prolonged coronal X-ray minimum, as documented by Chandra, while B was rising to, then falling from, a peak of its long-term (8 yr) starspot cycle. The FUV fluxes of the primary were steady over most of the STIS period, although the [Fe XII] 124 nm coronal forbidden line (T= 1.5 MK) partly mirrored the slowly rising X-ray fluxes. The FUV emissions of the secondary more closely tracked the rise and fall of its coronal luminosities, especially the "hot lines" like Si IV, C IV, and N V (T= 80,000-200,000 K), and coronal [Fe XII] itself. The hot lines of both stars were systematically redshifted, relative to narrow chromospheric emissions, by several km/s, showing little change in amplitude over the 4-y...

  6. A novel particle swarm optimizer hybridized with extremal optimization

    E-Print Network [OSTI]

    2008-05-26T23:59:59.000Z

    systems. EO successively updates extremely undesirable variables of a single sub- ..... optimal control of a class of hybrid systems, Applied Soft Computing 8.

  7. DOE Zero Energy Ready Home Case Study: Green Extreme Homes &...

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

    and lighting. A minisplit heat pump with 5 indoor heads heats and cools the home. Green Extreme Homes & Carl Franklin Homes - Garland, TX More Documents & Publications DOE...

  8. LDRD symposium focuses on materials in extremes, big data, and...

    National Nuclear Security Administration (NNSA)

    symposium focuses on materials in extremes, big data, and energy use impacts | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing...

  9. Extreme Methane Emissions from a Swiss Hydropower Reservoir

    E-Print Network [OSTI]

    Wehrli, Bernhard

    Extreme Methane Emissions from a Swiss Hydropower Reservoir: Contribution from Bubbling Sediments and their importance were quantified during a yearlong survey of a temperate hydropower reservoir. Measurements using

  10. An electronic compendium of extreme functions for the Gomory

    E-Print Network [OSTI]

    Matthias Köppe

    2014-11-18T23:59:59.000Z

    Nov 18, 2014 ... Abstract: In this note we announce the availability of an electronic compendium of extreme functions for Gomory--Johnson's infinite group ...

  11. Impact of horizontal resolution on simulation of precipitation extremes in an aqua-planet version of the Community Atmosphere Model (CAM)

    SciTech Connect (OSTI)

    Li, F.; Collins, W.D.; Wehner, M.F.; Williamson, D.L.; Olson, J.G.; Algieri, C.

    2011-03-01T23:59:59.000Z

    One key question regarding current climate models is whether the projection of climate extremes converges to a realistic representation as the spatial and temporal resolutions of the model are increased. Ideally the model extreme statistics should approach a fixed distribution once the resolutions are commensurate with the characteristic length and time scales of the processes governing the formation of the extreme phenomena of interest. In this study, a series of AGCM runs with idealized 'aquaplanet-steady-state' boundary conditions have been performed with the Community Atmosphere Model CAM3 to investigate the effect of horizontal resolution on climate extreme simulations. The use of the aquaplanet framework highlights the roles of model physics and dynamics and removes any apparent convergence in extreme statistics due to better resolution of surface boundary conditions and other external inputs. Assessed at a same large spatial scale, the results show that the horizontal resolution and time step have strong effects on the simulations of precipitation extremes. The horizontal resolution has a much stronger impact on precipitation extremes than on mean precipitation. Updrafts are strongly correlated with extreme precipitation at tropics at all the resolutions, while positive low-tropospheric temperature anomalies are associated with extreme precipitation at mid-latitudes.

  12. An investigation of symmetry in upper extremity strength during sagittal plane lifting tasks

    E-Print Network [OSTI]

    Key, Wendy Ross

    1994-01-01T23:59:59.000Z

    438. 76 461. 61 S. D. 26. 73 29. 60 18. 40 25. 03 103. 42 86. 07 Note: Data collected at a rate of 50 Hz. 52 APPENDIX I LIFTING TESTS DATA 53 LIFTING TESTS DATA (N) STOOP LIFT Left Ri ht SQUAT LIFT Left Ri ht Sub'ect Trial Av . S. D. Av . S.... D. Av . S. D. Av . S. D 2 137. 89 1. 97 118. 05 5. 30 162. 09 7. 77 148. 83 10. 75 3 113. 11 5. 56 97. 01 5. 14 120. 05 3. 83 130. 33 3. 72 4 143. 98 11. 16 134. 55 5. 78 119. 56 5. 77 129. 57 4. 50 2 134. 06 13. 08 88. 69 10. 18 135. 31 9. 04...

  13. Atmospheric Moisture Budget and Spatial Resolution Dependence of Precipitation Extremes in Aquaplanet Simulations

    SciTech Connect (OSTI)

    Yang, Qing; Leung, Lai-Yung R.; Rauscher, Sara; Ringler, Todd; Taylor, Mark

    2014-05-01T23:59:59.000Z

    This study investigates the resolution dependency of precipitation extremes in an aqua-planet framework. Strong resolution dependency of precipitation extremes is seen over both tropics and extra-tropics, and the magnitude of this dependency also varies with dynamical cores. Moisture budget analyses based on aqua-planet simulations with the Community Atmosphere Model (CAM) using the Model for Prediction Across Scales (MPAS) and High Order Method Modeling Environment (HOMME) dynamical cores but the same physics parameterizations suggest that during precipitation extremes moisture supply for surface precipitation is mainly derived from advective moisture convergence. The resolution dependency of precipitation extremes mainly originates from advective moisture transport in the vertical direction. At most vertical levels over the tropics and in the lower atmosphere over the subtropics, the vertical eddy transport of mean moisture field dominates the contribution to precipitation extremes and its resolution dependency. Over the subtropics, the source of moisture, its associated energy, and the resolution dependency during extremes are dominated by eddy transport of eddies moisture at the mid- and upper-troposphere. With both MPAS and HOMME dynamical cores, the resolution dependency of the vertical advective moisture convergence is mainly explained by dynamical changes (related to vertical velocity or omega), although the vertical gradients of moisture act like averaging kernels to determine the sensitivity of the overall resolution dependency to the changes in omega at different vertical levels. The natural reduction of variability with coarser resolution, represented by areal data averaging (aggregation) effect, largely explains the resolution dependency in omega. The thermodynamic changes, which likely result from non-linear feedback in response to the large dynamical changes, are small compared to the overall changes in dynamics (omega). However, after excluding the data aggregation effect in omega, thermodynamic changes become relatively significant in offsetting the effect of dynamics leading to reduce differences between the simulated and aggregated results. Compared to MPAS, the simulated stronger vertical motion with HOMME also results in larger resolution dependency. Compared to the simulation at fine resolution, the vertical motion during extremes is insufficiently resolved/parameterized at the coarser resolution even after accounting for the natural reduction in variability with coarser resolution, and this is more distinct in the simulation with HOMME. To reduce uncertainties in simulated precipitation extremes, future development in cloud parameterizations must address their sensitivity to spatial resolution as well as dynamical cores.

  14. Construction of new extremal unimodular lattices Philippe Gaborit \\Lambda

    E-Print Network [OSTI]

    Gaborit, Philippe

    Construction of new extremal unimodular lattices Philippe Gaborit \\Lambda July 22, 2003 Abstract In this paper we construct new extremal and optimal unimodular lattices in di­ mensions 36; 38; 42; 45; 52; 54; 60 and 68. We construct them in two ways: first in the case of dimensions congruent to 4 modulo 8

  15. UN Millennium Development Goal 1 Eradicate Extreme Poverty and Hunger

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    UN Millennium Development Goal 1 Eradicate Extreme Poverty and Hunger QUICK FACTS The World Bank estimates that 1.4 bill people in developing countries were living in extreme poverty in 2005. Recent into absolute poverty. About 25% of children under

  16. Controlling extreme events on complex Yu-Zhong Chen1

    E-Print Network [OSTI]

    Zhang, Junshan

    such as cybersecurity are discussed. E xtreme events occur on a large variety of complex networked systems, examples of intrinsically emergent behavior. Extreme events can have catastrophic consequences, demanding the articulation a physically practical control scheme against extreme events emerged from the intrinsic dynamic factors

  17. STATISTICS OF EXTREMES IN CLIMATE CHANGE Richard W. Katz

    E-Print Network [OSTI]

    Katz, Richard

    analysis available within the open source statistical programming language R. #12;2 OUTLINE Lecture 1 (9STATISTICS OF EXTREMES IN CLIMATE CHANGE Richard W. Katz Institute for Study of Society the application of the statistical theory of extreme values to climate, in general, and to climate change

  18. PROBLEM APPLICATIONS: EXERCISE SESSION ON ANALYSES OF EXTREMES

    E-Print Network [OSTI]

    Katz, Richard

    statistical programming language R. #12;2 TUTORIAL: Part 1 INTRODUCTION TO EXTREMES TOOLKIT AND CLIMATE as covariate) #12;4 PREPARATION (if use own laptop) Statistical programming language R (open source): DownloadRemes package within R (No familiarity with extRemes assumed) RESOURCES R: The R Project for Statistical

  19. OVERVIEW OF EXTREME VALUE ANALYSIS UNDER CLIMATE CHANGE

    E-Print Network [OSTI]

    Katz, Richard

    to handle this situation (e. g., "extRemes" package in open source statistical programming language R -- Statistical theory of extreme values Well established long ago -- Applications to climatology and hydrology (Fréchet type) "Heavy" upper tail with infinite rth-order moment if r 1/ (e. g., infinite variance if 1

  20. Extremely local MR representations: Youngmi Hur1 & Amos Ron2

    E-Print Network [OSTI]

    Maryland at College Park, University of

    Extremely local MR representations: L-CAMP Youngmi Hur1 & Amos Ron2 Workshop on sparse representations: UMD, May 2005 1 Math, UW-Madison 2 CS, UW-Madison #12;Wavelet and framelet constructions History of all local MR representations #12;L-CAMP: Extremely local MR constructions Bird's view of the CAP

  1. Extreme Loads for an Offshore Wind Turbine using Statistical

    E-Print Network [OSTI]

    Manuel, Lance

    Extreme Loads for an Offshore Wind Turbine using Statistical Extrapolation from Limited Field Data,itiscommontoeithercarry out extensive simulation studies or undertake a field measurement campaign. At the Blyth offshore wind here is to estimate extreme loads for an offshore wind turbine for which the environmental and load

  2. RisR1238(EN) Extreme Winds over Denmark

    E-Print Network [OSTI]

    Risø­R­1238(EN) Extreme Winds over Denmark from the NCEP/NCAR Reanalysis Helmut P. Frank Wind Energy Department Risø National Laboratory Roskilde, Denmark E-mail: helmut.frank@risoe.dk Risø National Laboratory, Roskilde, Denmark May 2001 #12;Abstract An extreme wind analysis of wind speed calculated

  3. Climatology of extreme rainfall from rain gauges and weather radar

    E-Print Network [OSTI]

    Stoffelen, Ad

    by conventional rain gauge networks. A 10-year radar-based climatology of rainfall depths for durations of 15 minClimatology of extreme rainfall from rain gauges and weather radar Aart Overeem #12;Thesis:30 PM in the Aula #12;Aart Overeem Climatology of extreme rainfall from rain gauges and weather radar

  4. A particle-in-cell plus Monte Carlo study of plasma-induced damage of normal incidence collector optics used in extreme ultraviolet lithography

    E-Print Network [OSTI]

    Zegeling, Paul

    ,6 In this paper, we present a study of plasma-induced sput- tering damage to the collector, using a spherical 3d3v at which the ions are created and their final energy is studied, revealing how the evolution In semiconductor industries there is a continuous de- mand for printing smaller structures on silicon wafers

  5. Extreme-ultraviolet polarimeter utilizing laser-generated high-order Nicole Brimhall, Matthew Turner, Nicholas Herrick, David D. Allred, R. Steven Turley,

    E-Print Network [OSTI]

    Hart, Gus

    with a repetition rate of 10 Hz. Per-shot energy monitoring of the laser discriminates against fluctuations, the instrument could conceivably operate through other ranges of harmonic wavelengths. An advantage of high har of high harmonic EUV light to be easily rotated using a half-wave plate in the generating laser beam

  6. OBSERVATIONS AND MODELING OF THE EMERGING EXTREME-ULTRAVIOLET LOOPS IN THE QUIET SUN AS SEEN WITH THE SOLAR DYNAMICS OBSERVATORY

    SciTech Connect (OSTI)

    Chitta, L. P.; Van Ballegooijen, A. A.; DeLuca, E. E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-15, Cambridge, MA 02138 (United States); Kariyappa, R.; Hasan, S. S. [Indian Institute of Astrophysics, Bangalore 560 034 (India); Hanslmeier, A. [Institut fuer Physik, IGAM, Universitaet Graz, Universitaetsplatz 5, A-8010 Graz (Austria)

    2013-05-01T23:59:59.000Z

    We used data from the Helioseismic and Magnetic Imager (HMI) and the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO) to study coronal loops at small scales, emerging in the quiet Sun. With HMI line-of-sight magnetograms, we derive the integrated and unsigned photospheric magnetic flux at the loop footpoints in the photosphere. These loops are bright in the EUV channels of AIA. Using the six AIA EUV filters, we construct the differential emission measure (DEM) in the temperature range 5.7-6.5 in log T (K) for several hours of observations. The observed DEMs have a peak distribution around log T Almost-Equal-To 6.3, falling rapidly at higher temperatures. For log T < 6.3, DEMs are comparable to their peak values within an order of magnitude. The emission-weighted temperature is calculated, and its time variations are compared with those of magnetic flux. We present two possibilities for explaining the observed DEMs and temperatures variations. (1) Assuming that the observed loops are composed of a hundred thin strands with certain radius and length, we tested three time-dependent heating models and compared the resulting DEMs and temperatures with the observed quantities. This modeling used enthalpy-based thermal evolution of loops (EBTEL), a zero-dimensional (0D) hydrodynamic code. The comparisons suggest that a medium-frequency heating model with a population of different heating amplitudes can roughly reproduce the observations. (2) We also consider a loop model with steady heating and non-uniform cross-section of the loop along its length, and find that this model can also reproduce the observed DEMs, provided the loop expansion factor {gamma} {approx} 5-10. More observational constraints are required to better understand the nature of coronal heating in the short emerging loops on the quiet Sun.

  7. Tracing direct and sequential two-photon double ionization of D{sub 2} in femtosecond extreme-ultraviolet laser pulses

    SciTech Connect (OSTI)

    Jiang, Y. H.; Kurka, M.; Kuehnel, K. U.; Ergler, Th.; Schroeter, C. D.; Moshammer, R. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Rudenko, A.; Foucar, L. [Max-Planck Advanced Study Group at CFEL, D-22607 Hamburg (Germany); Plesiat, E.; Perez-Torres, J. F.; Martin, F. [Departamento de Quimica C-9, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Herrwerth, O.; Lezius, M.; Kling, M. F. [Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Titze, J.; Jahnke, T.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Sanz-Vicario, J. L. [Instituto de Fisica, Universidad de Antioquia, Medellin (Colombia); Schoeffler, M.; Tilborg, J. van [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2010-02-15T23:59:59.000Z

    Two-photon double ionization (TPDI) of D{sub 2} is studied for 38-eV photons at the Free Electron Laser in Hamburg (FLASH). Based on model calculations, instantaneous and sequential absorption pathways are identified as separated peaks in the measured D{sup +}+D{sup +} fragment kinetic energy release (KER) spectra. The instantaneous process appears at high KER, corresponding to ionization at the molecule's equilibrium distance, in contrast to sequential ionization mainly leading to low-KER contributions. Measured fragment angular distributions are in good agreement with theory.

  8. Radial profile measurement of electron temperature in edge stochastic magnetic field layer of LHD using intensity ratio of extreme ultraviolet line emissions

    SciTech Connect (OSTI)

    Wang Erhui [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); Morita, Shigeru; Kobayashi, Masahiko; Murakami, Izumi; Goto, Motoshi [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); National Institute for Fusion Science, Toki 509-5292, Gifu (Japan); Dong Chunfeng [National Institute for Fusion Science, Toki 509-5292, Gifu (Japan)

    2012-10-15T23:59:59.000Z

    Vertical profile of neon line emissions in 30-650 A wavelength range has been observed in horizontally elongated plasma cross section of Large Helical Device (LHD). Intensity ratio between the neon line emissions is studied to measure the radial profile of electron temperature in the edge stochastic magnetic field layer of LHD. The edge temperature profile successfully obtained from the line ratio of NeVIII 2s-3p to 2p-3s transitions is compared with the simulation based on three-dimensional edge transport code. The result shows a reasonably good agreement with the edge temperature profile analyzed from atomic data and analysis structure code. The electron temperature at last closed flux surface measured from the intensity ratio is also in good agreement with that measured from Thomson scattering.

  9. Excitation of helium Rydberg states and doubly excited resonances in strong extreme ultraviolet fields: Full-dimensional quantum dynamics using exponentially tempered Gaussian basis sets

    SciTech Connect (OSTI)

    Kaprálová-Ž?ánská, Petra Ruth; Šmydke, Jan [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23 Prague 8 (Czech Republic) [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23 Prague 8 (Czech Republic); Department of Radiation and Chemical Physics, Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8 (Czech Republic); Civiš, Svatopluk [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23 Prague 8 (Czech Republic)] [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23 Prague 8 (Czech Republic)

    2013-09-14T23:59:59.000Z

    Recently optimized exponentially tempered Gaussian basis sets [P. R. Kapralova-Zdanska and J. Smydke, J. Chem. Phys. 138, 024105 (2013)] are employed in quantitative simulations of helium absorption cross-sections and two-photon excitation yields of doubly excited resonances. Linearly polarized half-infinite and Gaussian laser pulses at wavelengths 38–58 nm and large intensities up to 100 TW/cm{sup 2} are considered. The emphasis is laid on convergence of the results with respect to the quality of the Gaussian basis sets (typically limited by a number of partial waves, density, and spatial extent of the basis functions) as well as to the quality of the basis set of field-free states (typically limited by the maximum rotational quantum number and maximum excitation of the lower electron). Particular attention is paid to stability of the results with respect to varying complex scaling parameter. Moreover, the study of the dynamics is preceded by a thorough check of helium energies and oscillator strengths as they are obtained with the exponentially tempered Gaussian basis sets, being also compared with yet unpublished emission wavelengths measured in electric discharge experiments.

  10. Dynamics and manipulation of the dominant 13.5 nm in-band extreme ultraviolet emitting region of laser-produced Sn plasmas

    E-Print Network [OSTI]

    Yuspeh, Samuel Edward

    2011-01-01T23:59:59.000Z

    mesh overlaps, known as a bowtie, thus creating errors inadditional limitations. If a bowtie occurs (when the mesh ofthe mesh to remove the bowtie. This removal of the bowtie

  11. Thermodynamics of the Near-Extremal NS5-brane

    E-Print Network [OSTI]

    T. Harmark; N. A. Obers

    2005-10-25T23:59:59.000Z

    We consider the thermodynamics of the near-extremal NS5-brane in type IIA string theory. The central tool we use is to map phases of six-dimensional Kaluza-Klein black holes to phases of near-extremal M5-branes with a transverse circle in eleven-dimensional supergravity. By S-duality these phases correspond to phases of the near-extremal type IIA NS5-brane. One of our main results is that in the canonical ensemble the usual near-extremal NS5-brane background, dual to a uniformly smeared near-extremal M5-brane, is subdominant to a new background of near-extremal M5-branes localized on the transverse circle. This new stable phase has a limiting temperature, which lies above the Hagedorn temperature of the usual NS5-brane phase. We discuss the limiting temperature and compare the different behavior of the NS5-brane in the canonical and microcanonical ensembles. We also briefly comment on the thermodynamics of near-extremal Dp-branes on a transverse circle.

  12. Note: Hollow cathode lamp with integral, high optical efficiency isolation valve: A modular vacuum ultraviolet source

    SciTech Connect (OSTI)

    Sloan Roberts, F.; Anderson, Scott L. [Department of Chemistry, University of Utah, 315 S. 1400 E., Salt Lake City, Utah 84112 (United States)] [Department of Chemistry, University of Utah, 315 S. 1400 E., Salt Lake City, Utah 84112 (United States)

    2013-12-15T23:59:59.000Z

    The design and operating conditions of a hollow cathode discharge lamp for the generation of vacuum ultraviolet radiation, suitable for ultrahigh vacuum (UHV) application, are described in detail. The design is easily constructed, and modular, allowing it to be adapted to different experimental requirements. A thin isolation valve is built into one of the differential pumping stages, isolating the discharge section from the UHV section, both for vacuum safety and to allow lamp maintenance without venting the UHV chamber. The lamp has been used both for ultraviolet photoelectron spectroscopy of surfaces and as a “soft” photoionization source for gas-phase mass spectrometry.

  13. Nonadiabatic calculations of ultraviolet absorption cross section of sulfur monoxide: Isotopic effects on the photodissociation reaction

    SciTech Connect (OSTI)

    Danielache, Sebastian O.; Tomoya, Suzuki; Nanbu, Shinkoh [Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University, Chiyoda Ku, Tokyo 102-8554 (Japan)] [Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University, Chiyoda Ku, Tokyo 102-8554 (Japan); Kondorsky, Alexey [P. N. Lebedev Physical Institute of Russian Academy of Science, Leninsky pr., 53, Moscow, 119991 (Russian Federation) [P. N. Lebedev Physical Institute of Russian Academy of Science, Leninsky pr., 53, Moscow, 119991 (Russian Federation); Moscow Institute of Physics and Technology (State University), Institutsky per., 9, Dolgoprudny Moscow region, 141700 (Russian Federation); Tokue, Ikuo [Department of Chemistry, Faculty of Science, Niigata University, Ikarashi, Niigata 950-2181 (Japan)] [Department of Chemistry, Faculty of Science, Niigata University, Ikarashi, Niigata 950-2181 (Japan)

    2014-01-28T23:59:59.000Z

    Ultraviolet absorption cross sections of the main and substituted sulfur monoxide (SO) isotopologues were calculated using R-Matrix expansion technique. Energies, transition dipole moments, and nonadiabatic coupling matrix elements were calculated at MRCI/AV6Z level. The calculated absorption cross section of {sup 32}S{sup 16}O was compared with experimental spectrum; the spectral feature and the absolute value of photoabsorption cross sections are in good agreement. Our calculation predicts a long lived photoexcited SO* species which causes large non-mass dependent isotopic effects depending on the excitation energy in the ultraviolet region.

  14. Re-evaluation of SO2 release of the 15 June 1991 Pinatubo eruption using ultraviolet and infrared satellite sensors

    E-Print Network [OSTI]

    Rose, William I.

    Re-evaluation of SO2 release of the 15 June 1991 Pinatubo eruption using ultraviolet and infrared Infrared Radiation Sounder/2) sensor, whose data sets have a higher temporal resolution, are also analyzed ultraviolet and infrared satellite sensors, Geochem. Geophys. Geosyst., 5, Q04001, doi:10.1029/ 2003GC000654

  15. Observations of Gamma-Ray Bursts at Extreme Energies

    E-Print Network [OSTI]

    Aune, Taylor

    2012-01-01T23:59:59.000Z

    of Gamma-Ray Bursts . . . . . . . . . . . . . Redshift-CRUZ OBSERVATIONS OF GAMMA-RAY BURSTS AT EXTREME ENERGIES ADedication xix Acknowledgments xx 1 Gamma-Ray Bursts 1.1

  16. SUMMARY OF REVISED TORNADO, HURRICANE AND EXTREME STRAIGHT WIND...

    Office of Environmental Management (EM)

    @ E A R T H L I N K . N E T SUMMARY OF REVISED TORNADO, HURRICANE AND EXTREME STRAIGHT WIND CHARACTERISTICS AT NUCLEAR FACILITY SITES Categorization of Natural Hazard Phenomenon...

  17. Environmetally Assisted Cracking in Metals under Extreme Conditions

    E-Print Network [OSTI]

    Pham, Hieu

    2012-10-19T23:59:59.000Z

    of temperature, strain and extreme conditions (high pressure shock compression) on structural properties. The MD simulations show that hydrogen maintains the highest localization at grain boundaries in the vicinity of ambient temperatures, and grain boundaries...

  18. A Remarkable Property of the Dynamic Optimization Extremals?

    E-Print Network [OSTI]

    Delfim Fernando Marado Torres

    1910-10-81T23:59:59.000Z

    Page 1 ... A dynamic optimization continuous problem poses the question of what is .... We shall now formulate the celebrated Pontryagin maximum principle [22], .... is the case when the extremals don't change the value of a given function.

  19. Alternative mating tactics and extreme male dimorphism in fig wasps. 

    E-Print Network [OSTI]

    Cook, James M; Compton, Steven G; Herre, E Allen; West, Stuart A

    1997-01-01T23:59:59.000Z

    The dimorphisms in morphology and behaviour of male fig wasps are among the most extreme in the animal kingdom, and offer excellent oppotunities to test the predictions of certain sexual selection models.

  20. Sandia National Laboratories: extreme heat of deep geothermal...

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

    extreme heat of deep geothermal wells Sandia and Atlas-Copco Secoroc Advance to Phase 2 in Their Geothermal Energy Project On July 31, 2013, in Energy, Geothermal, News, News &...

  1. Transition-metal-hydrogen systems at extreme conditions 

    E-Print Network [OSTI]

    Scheler, Thomas Herbert

    2013-07-01T23:59:59.000Z

    The application of extreme conditions offers a general route for the synthesis of materials under equilibrium conditions. By finely tuning the thermodynamic variables of pressure and temperature one can manipulate matter ...

  2. Argonne Training Program on Extreme-Scale Computing Scheduled...

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

    Argonne Training Program on Extreme-Scale Computing Scheduled for August 2-14, 2015 Author: Brian Grabowski . January 29, 2015 Printer-friendly version ARGONNE, Ill., January 28,...

  3. Geocomputation's future at the extremes: high performance computing and nanoclients

    E-Print Network [OSTI]

    Clarke, Keith

    Geocomputation's future at the extremes: high performance computing and nanoclients K.C. Clarke; High performance computing; Tractability; Geocom- putation E-mail address: kclarke@geog.ucsb.edu (K

  4. Power System Extreme Event Detection: The Vulnerability Frontier

    E-Print Network [OSTI]

    Lesieutre, Bernard C.; Pinar, Ali; Roy, Sandip

    2007-01-01T23:59:59.000Z

    Screening in Electric Power Systems,” submitted to theIEEE Transactions on Power Systems. [3] Lesieutre, B.C. , S.Donde, and A. Pinar, “Power System Extreme Event Screening

  5. A Flexible Extreme Value Mixture Model A. MacDonalda

    E-Print Network [OSTI]

    Scarrott, Carl

    A Flexible Extreme Value Mixture Model A. MacDonalda , C.J. Scarrotta, , D. Leea , B. Darlowb , M motivated models for unusual or rare events, e.g. the upper or lower tails of a distribution. A new flexible

  6. Persisting cold extremes under 21st-century warming scenarios

    SciTech Connect (OSTI)

    Kodra, Evan A [ORNL; Steinhaeuser, Karsten J K [ORNL; Ganguly, Auroop R [ORNL

    2011-01-01T23:59:59.000Z

    Analyses of climate model simulations and observations reveal that extreme cold events are likely to persist across each land-continent even under 21st-century warming scenarios. The grid-based intensity, duration and frequency of cold extreme events are calculated annually through three indices: the coldest annual consecutive three-day average of daily maximum temperature, the annual maximum of consecutive frost days, and the total number of frost days. Nine global climate models forced with a moderate greenhouse-gas emissions scenario compares the indices over 2091 2100 versus 1991 2000. The credibility of model-simulated cold extremes is evaluated through both bias scores relative to reanalysis data in the past and multi-model agreement in the future. The number of times the value of each annual index in 2091 2100 exceeds the decadal average of the corresponding index in 1991 2000 is counted. The results indicate that intensity and duration of grid-based cold extremes, when viewed as a global total, will often be as severe as current typical conditions in many regions, but the corresponding frequency does not show this persistence. While the models agree on the projected persistence of cold extremes in terms of global counts, regionally, inter-model variability and disparity in model performance tends to dominate. Our findings suggest that, despite a general warming trend, regional preparedness for extreme cold events cannot be compromised even towards the end of the century.

  7. JOURNAL DE PHYSIQUE Colloque C4, supplkment au no 7 , Tome 39, Juillet 1978,page C4-221 STRATOSPHERIC POLLUTION RELATED ULTRAVIOLET RADIATION

    E-Print Network [OSTI]

    Boyer, Edmond

    -221 STRATOSPHERIC POLLUTION RELATED ULTRAVIOLET RADIATION PHENOMENA M. ACKERMAN Institut d'Abronomie Spatiale de aspects with recent examples. The new data obtained on the solar ultraviolet radiation since seven years are emphasized. 1. Introduction. - Solar ultraviolet radiation plays a fundamental role in the formation

  8. Infrared and ultraviolet problem for the Nelson model with variable coefficients

    E-Print Network [OSTI]

    Infrared and ultraviolet problem for the Nelson model with variable coefficients C. G´erard,1 , F of the Hamiltonian in the presence of the infrared problem, i.e. assuming that the boson mass tends to 0 at infinity state one usually speaks of the infrared problem or infrared divergence. The infrared problem arises

  9. Design and Evaluation of a Low-Cost Point-of-Use Ultraviolet Water Disinfection Device

    E-Print Network [OSTI]

    Kammen, Daniel M.

    receive chlorinated water while another receives contaminated water with no residual level of chlorineDesign and Evaluation of a Low-Cost Point-of-Use Ultraviolet Water Disinfection Device Alicia Cohn around the world to supply safe drinking water. We have developed a device for disinfecting drinking

  10. Assessment of a low-cost, point-of-use, ultraviolet water disinfection technology

    E-Print Network [OSTI]

    Kammen, Daniel M.

    lack access to safe drinking water and an accelerated effort is required if the MDG is to be met (WHOAssessment of a low-cost, point-of-use, ultraviolet water disinfection technology Sarah A. Brownell, Portland, OR, USA Rachel L. Peletz Centre for Affordable Water and Sanitation Technology, Calgary, Canada

  11. Non-thermal calcination by ultraviolet irradiation in the synthesis of microporous materials

    E-Print Network [OSTI]

    Parikh, Atul N.

    Non-thermal calcination by ultraviolet irradiation in the synthesis of microporous materials Atul N-directing agents in the synthesis of microporous materials. The method relies on the exposure of the sample. This method is applicable in making new materials from organic­inorganic pre- cursors and holds promise

  12. Recent Experimental and Theoretical Advances in Microdrilling of Polymers with Ultraviolet Laser Beams

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Libération, F-33405 Talence, FRANCE E-mail: s.lazare@lpcm.u-bordeaux1.fr ABSTRACT Laser drilling becomes is now in progress. Keywords: Materials, laser, processing, drilling, model, profile, mechanisms, polymer1 Recent Experimental and Theoretical Advances in Microdrilling of Polymers with Ultraviolet Laser

  13. Simulation of Two-Dimensional Ultraviolet Spectroscopy of Amyloid Fibrils Darius Abramavicius,

    E-Print Network [OSTI]

    Mukamel, Shaul

    diseases. Amyloid fibrils are formed by a wide variety of peptides and proteins and can be distinguishedSimulation of Two-Dimensional Ultraviolet Spectroscopy of Amyloid Fibrils Jun Jiang, Darius, 2010 Revealing the structure and aggregation mechanism of amyloid fibrils is essential

  14. Signatures of the Protein Folding Pathway in Two-Dimensional Ultraviolet Spectroscopy

    E-Print Network [OSTI]

    Mukamel, Shaul

    Signatures of the Protein Folding Pathway in Two-Dimensional Ultraviolet Spectroscopy Jun Jiang of the signals provides a quantitative marker of protein folding status, accessible by both theoretical calculations and experiments. SECTION: Biophysical Chemistry and Biomolecules Protein folding is an important

  15. Extremely stable Nafion based carbon monoxide sensor

    SciTech Connect (OSTI)

    van der Wal; P.D. de Rooij, N.F.; Koudelka-Hep, M. [Univ. of Neuchatel (Switzerland)

    1996-12-31T23:59:59.000Z

    At present carbon monoxide sensing devices are readily available for many industrial applications. The sensors used in these devices include electrochemical sensors, semiconductor sensors, calorimetric detectors and infra red detectors. From these devices the electrochemical sensors are of specific interest because of their high selectivity and low power consumption. This makes them suitable for use in battery operated devices, e.g. for domestic safety. However, their relatively high price and frequent need for recalibration seriously hamper their utilisation on a large scale. The relatively high price of electrochemical CO sensors is caused by the complexity of fabrication. They are composed of a cylindrical housing, with one end the counter and reference electrodes, and on the other the working electrode. The electrodes are made out of Teflon bonded platinum black on a Teflon substrate and the electrolyte is a sulfuric acid solution. The aim of this work was to develop electrochemical CO sensors, that are small and cheaper than the existing products. The approach concentrated on three main aspects: (a) simplification of the device assembly by investigating the of using a planar sensor design, (b) use of mass production compatible fabrication, and (c) replacement of the sulfuric acid.

  16. Nearly extremal apparent horizons in simulations of merging black holes

    E-Print Network [OSTI]

    Geoffrey Lovelace; Mark A. Scheel; Robert Owen; Matthew Giesler; Reza Katebi; Bela Szilagyi; Tony Chu; Nicholas Demos; Daniel A. Hemberger; Lawrence E. Kidder; Harald P. Pfeiffer; Nousha Afshari

    2015-02-27T23:59:59.000Z

    The spin angular momentum $S$ of an isolated Kerr black hole is bounded by the surface area $A$ of its apparent horizon: $8\\pi S \\le A$, with equality for extremal black holes. In this paper, we explore the extremality of individual and common apparent horizons for merging, rapidly spinning binary black holes. We consider simulations of merging black holes with equal masses $M$ and initial spin angular momenta aligned with the orbital angular momentum, including new simulations with spin magnitudes up to $S/M^2 = 0.994$. We measure the area and (using approximate Killing vectors) the spin on the individual and common apparent horizons, finding that the inequality $8\\pi S A$ and for which our lower bound on their Booth-Fairhurst extremality exceeds unity. These superextremal surfaces are always surrounded by marginally outer trapped surfaces (i.e., by apparent horizons) with $8\\pi Sextremality lower bound on the enclosing apparent horizon is always less than unity but can exceed the value for an extremal Kerr black hole. (Abstract abbreviated.)

  17. Could the Earth's surface Ultraviolet irradiance be blamed for the global warming? (II) ----Ozone layer depth reconstruction via HEWV effect

    E-Print Network [OSTI]

    Chen, Jilong; Zheng, Yujun

    2014-01-01T23:59:59.000Z

    It is suggested by Chen {\\it et al.} that the Earth's surface Ultraviolet irradiance ($280-400$ nm) could influence the Earth's surface temperature variation by "Highly Excited Water Vapor" (HEWV) effect. In this manuscript, we reconstruct the developing history of the ozone layer depth variation from 1860 to 2011 based on the HEWV effect. It is shown that the reconstructed ozone layer depth variation correlates with the observational variation from 1958 to 2005 very well ($R=0.8422$, $P>99.9\\%$). From this reconstruction, we may limit the spectra band of the surface Ultraviolet irradiance referred in HEWV effect to Ultraviolet B ($280-320$ nm).

  18. Repair of 254 nm ultraviolet-induced (6-4) photoproducts: monoclonal antibody recognition and differential defects in xeroderma pigmentosum complementation groups A, D, and variant

    SciTech Connect (OSTI)

    Hiramoto, T.; Matsunaga, T.; Ichihashi, M.; Nikaido, O.; Fujiwara, Y.; Mishima, Y. (Kobe Univ. (Japan))

    1989-11-01T23:59:59.000Z

    Repair kinetics of ultraviolet (UV) light-induced (6-4) photoproducts in xeroderma pigmentosum complementation group A, D, and variant cells were studied by the enzyme-linked immunosorbent assay (ELISA) using a specific monoclonal antibody raised against (6-4) photoproducts, together with unscheduled DNA synthesis (UDS) and loss of T4 endonuclease V-susceptible sites (ESS). Group AXP35KO cells completely failed to repair both ESS (cyclobutane pyrimidine dimers) and antibody-recognizing (6-4) photoproducts until tested 24 h after irradiation, and had 2% early-time UDS. Group DXP43KO cells showed about 10% removal of both (6-4) photoproducts and ESS in 24 h, despite showing a residually higher level of 40% early-time and cumulative UDS. Thus, the results substantiated the extreme UV hypersensitivity of XP group A and D cells. However, XP52KO variant cells exhibited the normal level of UDS and ESS loss, but a slightly reduced repair of antibody-recognizing (6-4) photoproducts at 6 and 12 h after irradiation, which may account for a small UV hypersensitivity of the XP variant cells.

  19. The genealogy of extremal particles of Branching Brownian Motion

    E-Print Network [OSTI]

    Arguin, Louis-Pierre; Kistler, Nicola

    2010-01-01T23:59:59.000Z

    Branching Brownian Motion describes a system of particles which diffuse in space and split into offsprings according to a certain random mechanism. In virtue of the groundbreaking work by M. Bramson on the convergence of solutions of the Fisher-KPP equation to traveling waves, the law of the rightmost particle in the limit of large times is rather well understood. In this work, we address the full statistics of the extremal particles (first-, second-, third- etc. largest). In particular, we prove that in the large $t-$limit, such particles descend with overwhelming probability from ancestors having split either within a distance of order one from time $0$, or within a distance of order one from time $t$. The approach relies on characterizing, up to a certain level of precision, the paths of the extremal particles. As a byproduct, a heuristic picture of Branching Brownian Motion ``at the edge'' emerges, which sheds light on the still unknown limiting extremal process.

  20. Intensification of hot extremes in the United States

    SciTech Connect (OSTI)

    Diffenbaugh, Noah [Stanford University; Ashfaq, Moetasim [ORNL

    2010-01-01T23:59:59.000Z

    Governments are currently considering policies that will limit greenhouse gas concentrations, including negotiation of an international treaty to replace the expiring Kyoto Protocol. Existing mitigation targets have arisen primarily from political negotiations, and the ability of such policies to avoid dangerous impacts is still uncertain. Using a large suite of climate model experiments, we find that substantial intensification of hot extremes could occur within the next 3 decades, below the 2 C global warming target currently being considered by policy makers. We also find that the intensification of hot extremes is associated with a shift towards more anticyclonic atmospheric circulation during the warm season, along with warm-season drying over much of the U.S. The possibility that intensification of hot extremes could result from relatively small increases in greenhouse gas concentrations suggests that constraining global warming to 2 C may not be sufficient to avoid dangerous climate change.

  1. Extreme high-head portables provide more pumping options

    SciTech Connect (OSTI)

    Fiscor, S.

    2006-10-15T23:59:59.000Z

    Three years ago, Godwin Pumps, one of the largest manufacturers of portable pumps, introduced its Extreme Duty High Lift (HL) series of pumps and more mines are finding unique applications for these pumps. The Extreme HL series is a range single-stage Dri-Prime pumps with heads up to 600 feet and flows up to 5,000 gallons per minute. The American Coal Co.'s Galatia mine, an underground longwall mine in southern Illinois, used an HL 160 to replace a multiple-staged centrifugal pump. It provided Galatia with 1,500 gpm at 465 ft. 3 photos.

  2. Climate, extreme heat, and electricity demand in California

    SciTech Connect (OSTI)

    Miller, N.L.; Hayhoe, K.; Jin, J.; Auffhammer, M.

    2008-04-01T23:59:59.000Z

    Climate projections from three atmosphere-ocean climate models with a range of low to mid-high temperature sensitivity forced by the Intergovernmental Panel for Climate Change SRES higher, middle, and lower emission scenarios indicate that, over the 21st century, extreme heat events for major cities in heavily air-conditioned California will increase rapidly. These increases in temperature extremes are projected to exceed the rate of increase in mean temperature, along with increased variance. Extreme heat is defined here as the 90 percent exceedance probability (T90) of the local warmest summer days under the current climate. The number of extreme heat days in Los Angeles, where T90 is currently 95 F (32 C), may increase from 12 days to as many as 96 days per year by 2100, implying current-day heat wave conditions may last for the entire summer, with earlier onset. Overall, projected increases in extreme heat under the higher A1fi emission scenario by 2070-2099 tend to be 20-30 percent higher than those projected under the lower B1 emission scenario, ranging from approximately double the historical number of days for inland California cities (e.g. Sacramento and Fresno), up to four times for previously temperate coastal cities (e.g. Los Angeles, San Diego). These findings, combined with observed relationships between high temperature and electricity demand for air-conditioned regions, suggest potential shortfalls in transmission and supply during T90 peak electricity demand periods. When the projected extreme heat and peak demand for electricity are mapped onto current availability, maintaining technology and population constant only for demand side calculations, we find the potential for electricity deficits as high as 17 percent. Similar increases in extreme heat days are suggested for other locations across the U.S. southwest, as well as for developing nations with rapidly increasing electricity demands. Electricity response to recent extreme heat events, such as the July 2006 heat wave in California, suggests that peak electricity demand will challenge current supply, as well as future planned supply capacities when population and income growth are taken into account.

  3. Non-extremal Kerr black holes as particle accelerators

    E-Print Network [OSTI]

    Sijie Gao; Changchun Zhong

    2011-08-03T23:59:59.000Z

    It has been shown that extremal Kerr black holes can be used as particle accelerators and arbitrarily high energy may be obtained near the event horizon. We study particle collisions near the event horizon (outer horizon) and Cauchy horizon (inner horizon) of a non-extremal Kerr black hole. Firstly, we provide a general proof showing that particles cannot collide with arbitrarily high energies at the outter horizon. Secondly, we show that ultraenergetic collisions can occur near the inner horizon of a Kerr black hole with any spin parameter $a$.

  4. Extreme Value Analysis of Tidal Stream Velocity Perturbations

    SciTech Connect (OSTI)

    Harding, Samuel; Thomson, Jim; Polagye, Brian; Richmond, Marshall C.; Durgesh, Vibhav; Bryden, Ian

    2011-04-26T23:59:59.000Z

    This paper presents a statistical extreme value analysis of maximum velocity perturbations from the mean flow speed in a tidal stream. This study was performed using tidal velocity data measured using both an Acoustic Doppler Velocimeter (ADV) and an Acoustic Doppler Current Profiler (ADCP) at the same location which allows for direct comparison of predictions. The extreme value analysis implements of a Peak-Over-Threshold method to explore the effect of perturbation length and time scale on the magnitude of a 50-year perturbation.

  5. TECA: A Parallel Toolkit for Extreme Climate Analysis

    SciTech Connect (OSTI)

    Prabhat, Mr; Ruebel, Oliver; Byna, Surendra; Wu, Kesheng; Li, Fuyu; Wehner, Michael; Bethel, E. Wes

    2012-03-12T23:59:59.000Z

    We present TECA, a parallel toolkit for detecting extreme events in large climate datasets. Modern climate datasets expose parallelism across a number of dimensions: spatial locations, timesteps and ensemble members. We design TECA to exploit these modes of parallelism and demonstrate a prototype implementation for detecting and tracking three classes of extreme events: tropical cyclones, extra-tropical cyclones and atmospheric rivers. We process a modern TB-sized CAM5 simulation dataset with TECA, and demonstrate good runtime performance for the three case studies.

  6. Synchrotron Vacuum-Ultraviolet Postionization Mass Spectrometry with Laser and Ion Probes for Intact Molecular Spatial Mapping of Lignin

    E-Print Network [OSTI]

    Takahashi, Lynelle Kazue

    2011-01-01T23:59:59.000Z

    27, 289. Thompson, M. W. Vacuum 2002, 66, 99. McPhail, D. J.Gibson, J. K. Journal of Vacuum Science and Technology 1995,Chemical Society. Vacuum ultraviolet photoionization coupled

  7. Tyrosine/Cysteine Cluster Sensitizing Human ?D-Crystallin to Ultraviolet Radiation-Induced Photoaggregation in Vitro

    E-Print Network [OSTI]

    Schafheimer, Steven Nathaniel

    Ultraviolet radiation (UVR) exposure is a major risk factor for age-related cataract, a protein-aggregation disease of the human lens often involving the major proteins of the lens, the crystallins. ?D-Crystallin (H?D-Crys) ...

  8. Final LDRD report :ultraviolet water purification systems for rural environments and mobile applications.

    SciTech Connect (OSTI)

    Banas, Michael Anthony; Crawford, Mary Hagerott; Ruby, Douglas Scott; Ross, Michael P.; Nelson, Jeffrey Scott; Allerman, Andrew Alan; Boucher, Ray

    2005-11-01T23:59:59.000Z

    We present the results of a one year LDRD program that has focused on evaluating the use of newly developed deep ultraviolet LEDs in water purification. We describe our development efforts that have produced an LED-based water exposure set-up and enumerate the advances that have been made in deep UV LED performance throughout the project. The results of E. coli inactivation with 270-295 nm LEDs are presented along with an assessment of the potential for applying deep ultraviolet LED-based water purification to mobile point-of-use applications as well as to rural and international environments where the benefits of photovoltaic-powered systems can be realized.

  9. DNA synthesis in pigmented and non-pigmented mutants of Serratia marcescens after ultra-violet irradiation

    E-Print Network [OSTI]

    Russo, Salvadore William

    1973-01-01T23:59:59.000Z

    DNA SYNTHESIS IN PIGNENTED AND NON-PIGKENTED MUTANTS OF SERRATIA MARCESCENS AFTER ULTRAVIOLET IRRADIATION A Thesis by SALVADORE NILLIAM RUSSO, JR. Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE August 1973 Major Subject: Biochemistry DNA SYNTHESIS IN PIGMENTED AND NON-PIGMENTED MUTANTS OF SERRATIA MARCESCENS AFTER ULTRAVIOLET IRRADIATION A' Thesis by SALVADORE WILLIAM RUSSO, JR. Approved...

  10. The effects of selected wavelengths and energy levels of ultraviolet irradiation on the endopeptidase and hemolytic activity of Aeromonas proteolytica

    E-Print Network [OSTI]

    Lovett, David Franklin

    1972-01-01T23:59:59.000Z

    irradiation of the radiosensitive B strain of Escherichia cali induced, at a high frequency, a radiation resistance strain, which she designated as B/r. Six years later Clark (2) found that this B/r strain was not only more resistant to ultraviolet...THE EFFECTS OF SELECTED WAVELENGTHS AND ENERGY LEVELS OF ULTRAVIOLET IRRADIATION ON THE ENDOPEPTIDASE AND HEMOLYTIC ACTIVITY OF AEROMONAS PROTEOLYTICA A Thesis by DAVID FRANKLIN LOVETT Submitted to the Graduate College of Texas ASM...

  11. FRONTIER SYNCHROTRON INFRARED SPECTROSCOPY BEAMLINE UNDER EXTREME CONDITIONS (FIS)

    E-Print Network [OSTI]

    Ohta, Shigemi

    FRONTIER SYNCHROTRON INFRARED SPECTROSCOPY BEAMLINE UNDER EXTREME CONDITIONS (FIS) Proposal Team: L INFORMATION · TECHNIQUE(S): Fourier transform infrared spectroscopy; Raman and visible spectroscopy; Diamond techniques combined with DACs; Laser heating techniques combined with DACs. · SOURCE: Large-gap (90 mm

  12. ITEP Webinar: Extreme Weather Events and Climate Change

    Broader source: Energy.gov [DOE]

    Attend this Institute for Tribal Environmental Professionals (ITEP) webinar and hear about the known variability in extreme weather such as excessive heat, cold waves, floods, droughts, hurricanes, severe thunderstorms and tornadoes. Projections and uncertainties of how these hazards might change due to global warming will be reviewed.

  13. Extremal Fields and Neighboring Optimal Control of Constrained Systems 

    E-Print Network [OSTI]

    Harris, Matthew Wade

    2012-02-14T23:59:59.000Z

    this form, and so this work fills a void in the study of extremal fields and neighboring optimal control of constrained systems. Only first and second-order terms are written down, but the approach is systematic and higher order expressions can be found...

  14. Laura Roach Islamic Extremism: Undermining a Fundamentalist Movement in Indonesia

    E-Print Network [OSTI]

    New Hampshire, University of

    Laura Roach Islamic Extremism: Undermining a Fundamentalist Movement in Indonesia College: COLSA, Major: EREC Freshman Editor: Stephanie Weiner #12;I. Problem Indonesia has the largest Muslim population, Indonesia is not an Islamic state; it is the third largest democracy in the world.1 Unsurprisingly

  15. Evidence to the contrary: extreme weekly returns are underreactions

    E-Print Network [OSTI]

    Kelley, Eric Kyle

    2004-11-15T23:59:59.000Z

    contrarian profits are followed by a long run of momentum profits. In fact, these profits are strong enough to produce a significant momentum effect over the full year following portfolio formation. Thus, the market does not appear to view extreme weekly...

  16. RisR1437(EN) Wind Simulation for Extreme

    E-Print Network [OSTI]

    -Gaussiske processer simuleres med en en transformation fra de Gaussiake tilfælde under hensyntagen til forvræng.1 The Gaussian generator 50 6.2 The selection problem 51 6.3 Gaussian gust in a single process 51 6.4 Gaussian integrity of a wind turbine structure involves analyses of fatigue loading as well as extreme loading

  17. Quantitative Models for Operational Risk: Extremes, Dependence and Aggregation

    E-Print Network [OSTI]

    Embrechts, Paul

    risk data lend themselves easily to a full quantitative analysis. For example, legal risk defiesQuantitative Models for Operational Risk: Extremes, Dependence and Aggregation V. Chavez, the financial industry is looking for qualitative approaches to and quantitative models for operational risk

  18. REVIEW Open Access Climate change, air pollution and extreme events

    E-Print Network [OSTI]

    REVIEW Open Access Climate change, air pollution and extreme events leading to increasing dramatically during the past few decades not only in industrialized countries. Urban air pollution from motor be explained only in changes occurred in the environment. Despite some differences in the air pollution profile

  19. INHIBITION OF PHOTOSYNTHESIS IN CERTAIN ALGAE BY EXTREME RED LIGHT

    E-Print Network [OSTI]

    Govindjee

    INHIBITION OF PHOTOSYNTHESIS IN CERTAIN ALGAE BY EXTREME RED LIGHT GOVINDJEE, EUGENE RABINOWITCH. INTRODUCTION It was shown in preceding papers (9, 10) that when the unicellular red alga Por- phyridium), these algae, when exposed to monochromatic light (bands isolated by a grating monochromator, band half

  20. Measuring Thermal Transport in Extreme Environments: Thermal Conductivity

    E-Print Network [OSTI]

    Braun, Paul

    Chen California Institute of Technology Jackie Li University of Michigan supported by CarnegieMeasuring Thermal Transport in Extreme Environments: Thermal Conductivity of Water Ice VII to 20 GPa David G. Cahill, Wen-Pin Hsieh, Dallas Trinkle, University of Illinois at Urbana-Champaign Bin

  1. Causal Analysis of the Unanticipated Extremity Exposure at HFEF

    SciTech Connect (OSTI)

    David E. James; Charles R. Posegate; Thomas P. Zahn; Alan G. Wagner

    2011-11-01T23:59:59.000Z

    This report covers the unintended extremity exposure to an operator while handling a metallurgical mount sample of irradiated fuel following an off-scale high beta radiation reading of the sample. The decision was made to continue working after the meter indicated high off-scale by the HPT Supervisor, which resulted in the operator at the next operation being exposed.

  2. ORIGINAL ARTICLE Acupuncture for Upper-Extremity Rehabilitation in Chronic

    E-Print Network [OSTI]

    Schaechter, Judith D.

    , and improvement trends in UE motor function (P .09) and digit ROM (P .06). Conclusions: Based on ITT analyses, we Sham-Controlled Study Peter M. Wayne, PhD, David E. Krebs, PhD, Eric A. Macklin, PhD, Rosa Schnyer, Lic. Acupuncture for upper- extremity rehabilitation in chronic stroke: a randomized sham- controlled study. Arch

  3. How Climate Change is Playing Out in Minnesota: Extreme Weather

    E-Print Network [OSTI]

    Minnesota, University of

    How Climate Change is Playing Out in Minnesota: Extreme Weather Dr. Mark Seeley Dept of Soil, Water Climate Headlines Data Sources Changing Minnesota Climate Features Climate Consequences Implications for Severe Weather #12;Three Reasons to Accept That Climate Change is Real #12;#12;Stationary (1) Cyclical (2

  4. Extreme conditions during multibubble cavitation: Sonoluminescence as a spectroscopic probe

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Extreme conditions during multibubble cavitation: Sonoluminescence as a spectroscopic probe Kenneth Cavitation MBSL Plasma a b s t r a c t We review recent work on the use of sonoluminescence (SL) to probe spectroscopically the conditions created during cavitation, both in clouds of collapsing bubbles (multibubble

  5. Improving Societal Outcomes of Extreme Weather in a

    E-Print Network [OSTI]

    Neff, Jason

    of carbon dioxide and other greenhouse gases Adaptation: long-term or fundamental changes people make Despite hazard mitigation efforts and scientific and technological ad- vances, extreme weather events and ad- dressing local causes of harm through participatory, community-based efforts formulated within

  6. An extreme cytoplasmic bottleneck in the modern European cultivated potato

    E-Print Network [OSTI]

    Provan, Jim

    An extreme cytoplasmic bottleneck in the modern European cultivated potato (Solanum tuberosum and nuclear diversity in the gene pool of the European cultivated potato (Solanum tuberosum ssp. tuberosum to amplify polymorphic products in a range of potato cultivars. Combining the data from seven polymorphic cp

  7. Ultraviolet spectrophotometry of close binary systems: CV Velorum, RS Vulpeculae and DH Cephei

    SciTech Connect (OSTI)

    Wu, C.C.; Eaton, J.A.

    1981-01-01T23:59:59.000Z

    The ultraviolet magnitudes of CV Velorum, RS Vulpeculae and DH Cephei are reported. Aside from twenty observations of CV Velorum which fell inside the primary eclipse, all data were obtained for phases outside eclipse. Observations were made with the University of Greningen experiment on board the Astronomical Netherlands Satellite. The instrument consists of a 22 cm aperture Cassegrain telescope followed by a five channel grating spectrophotometer. Instrument operation modes and data correction procedures are briefly described.

  8. Heats of vaporization of room temperature ionic liquids by tunable vacuum ultraviolet photoionization

    SciTech Connect (OSTI)

    Chambreau, Steven D.; Vaghjiani, Ghanshyam L.; To, Albert; Koh, Christine; Strasser, Daniel; Kostko, Oleg; Leone, Stephen R.

    2009-11-25T23:59:59.000Z

    The heats of vaporization of the room temperature ionic liquids (RTILs) N-butyl-N-methylpyrrolidinium bistrifluorosulfonylimide, N-butyl-N-methylpyrrolidinium dicyanamide, and 1-butyl-3-methylimidazolium dicyanamide are determined using a heated effusive vapor source in conjunction with single photon ionization by a tunable vacuum ultraviolet synchrotron source. The relative gas phase ionic liquid vapor densities in the effusive beam are monitored by clearly distinguished dissociative photoionization processes via a time-of-flight mass spectrometer at a tunable vacuum ultraviolet beamline 9.0.2.3 (Chemical Dynamics Beamline) at the Advanced Light Source synchrotron facility. Resulting in relatively few assumptions, through the analysis of both parent cations and fragment cations, the heat of vaporization of N-butyl-N-methylpyrrolidinium bistrifluorosulfonylimide is determined to be Delta Hvap(298.15 K) = 195+-19 kJ mol-1. The observed heats of vaporization of 1-butyl-3-methylimidazolium dicyanamide (Delta Hvap(298.15 K) = 174+-12 kJ mol-1) and N-butyl-N-methylpyrrolidinium dicyanamide (Delta Hvap(298.15 K) = 171+-12 kJ mol-1) are consistent with reported experimental values using electron impact ionization. The tunable vacuum ultraviolet source has enabled accurate measurement of photoion appearance energies. These appearance energies are in good agreement with MP2 calculations for dissociative photoionization of the ion pair. These experimental heats of vaporization, photoion appearance energies, and ab initio calculations corroborate vaporization of these RTILs as intact cation-anion ion pairs.

  9. Proliferative and toxic effects of ultraviolet light and inflammation on epidermal pigment cells

    SciTech Connect (OSTI)

    Nordlund, J.J.; Ackles, A.E.; Traynor, F.F.

    1981-10-01T23:59:59.000Z

    The ear of the mouse is useful for studying the effects of ultraviolet light on epidermal pigment cells. The quantity of light penetrating into the skin causing an inflammatory response can be assessed easily by measuring with an engineering calipers the swelling of the ear. The inflammatory response of the ear exhibits a linear relationship to the dose of light delivered. We observed that doses of shortwave ultraviolet light which are noninflammatory when repeated at daily intervals induce moderate to severe inflammation. Small doses of psoralen and prolonged exposure to UVA (PUVA) were more inflammatory than larger amounts of psoralen and short exposure to light. Doses of shortwave ultraviolet light and PUVA which produce only a minimal inflammation of the skin stimulate the proliferation of epidermal melanocytes. In contrast, PUVA in doses sufficiently large to cause a marked inflammatory reaction in the skin seems injurious to pigment cells and kills them or causes only a minimal proliferative response. The inflammatory reaction itself does not seem to stimulate or inhibit the proliferation of melanocytes. Prostaglandins A, E, and F2 alpha have no effect on the proliferation of epidermal pigment cells. In contrast, dimethyl sulfoxide (DMSO) and allergic contact dermatitis increase the numerical density of pigment cells. Steroids may block the function of the enzyme tyrosinase. Our experiments indicate that pigment cells, like many other varieties of cells, are susceptible to injury and can be killed at least by large doses of PUVA.

  10. SN 2008ha: AN EXTREMELY LOW LUMINOSITY AND EXCEPTIONALLY LOW ENERGY SUPERNOVA

    SciTech Connect (OSTI)

    Foley, Ryan J.; Kirshner, Robert P.; Challis, Peter J.; Friedman, Andrew S. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chornock, Ryan; Filippenko, Alexei V.; Ganeshalingam, Mohan; Li, Weidong; Cenko, S. Bradley; Modjaz, Maryam; Silverman, Jeffrey M. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Wood-Vasey, W. Michael [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States)], E-mail: rfoley@cfa.harvard.edu

    2009-08-15T23:59:59.000Z

    We present ultraviolet, optical, and near-infrared photometry as well as optical spectra of the peculiar supernova (SN) 2008ha. SN 2008ha had a very low peak luminosity, reaching only M{sub V} = -14.2 mag, and low line velocities of only {approx}2000 km s{sup -1} near maximum brightness, indicating a very small kinetic energy per unit mass of ejecta. Spectroscopically, SN 2008ha is a member of the SN 2002cx-like class of SNe, a peculiar subclass of SNe Ia; however, SN 2008ha is the most extreme member, being significantly fainter and having lower line velocities than the typical member, which is already {approx}2 mag fainter and has line velocities {approx}5000 km s{sup -1} smaller (near maximum brightness) than a normal SN Ia. SN 2008ha had a remarkably short rise time of only {approx}10 days, significantly shorter than either SN 2002cx-like objects ({approx}15 days) or normal SNe Ia ({approx}19.5 days). The bolometric light curve of SN 2008ha indicates that SN 2008ha peaked at L {sub peak} = (9.5 {+-} 1.4) x 10{sup 40} erg s{sup -1}, making SN 2008ha perhaps the least luminous SN ever observed. From its peak luminosity and rise time, we infer that SN 2008ha generated (3.0 {+-} 0.9) x 10{sup -3} M {sub sun} of {sup 56}Ni, had a kinetic energy of {approx}2 x 10{sup 48} erg, and ejected 0.15 M {sub sun} of material. The host galaxy of SN 2008ha has a luminosity, star formation rate, and metallicity similar to those of the Large magellanic Cloud. We classify three new (and one potential) members of the SN 2002cx-like class, expanding the sample to 14 (and one potential) members. The host-galaxy morphology distribution of the class is consistent with that of SNe Ia, Ib, Ic, and II. Several models for generating low-luminosity SNe can explain the observations of SN 2008ha; however, if a single model is to describe all SN 2002cx-like objects, deflagration of carbon-oxygen white dwarfs, with SN 2008ha being a partial deflagration and not unbinding the progenitor star, is preferred. The rate of SN 2008ha-like events is {approx}10% of the SN Ia rate, and in the upcoming era of transient surveys, several thousand similar objects may be discovered, suggesting that SN 2008ha may be the tip of a low-luminosity transient iceberg.

  11. Investigating Iron Ions | EMSL

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

    Investigating Iron Ions Investigating Iron Ions Computer code provides detailed predictions of highly charged ions in water Using resources at EMSL, scientists obtained...

  12. Segmented Ultralight Pre-Aligned Rotor for Extreme-Scale Wind Turbines

    SciTech Connect (OSTI)

    Loth, E.; Steele, A.; Ichter, B.; Selig, M.; Moriarty, P.

    2012-01-01T23:59:59.000Z

    To alleviate the mass-scaling issues associated with conventional upwind rotors of extreme-scale turbines, a downwind rotor concept is proposed which employs fixed blade curvature based on force alignment at rated conditions. For a given peak stress constraint, the reduction in downwind cantilever loads allows reduced shell and spar thickness, and thus a reduced blade mass as compared with a conventional upwind rotor, especially as rotor sizes approach extreme-scales. To quantify this mass reduction, a Finite Element Analysis was conducted for a 10 MW rated rotor based on the NREL offshore 5 MW baseline wind turbine. The results show that this 'pre-alignment' yields a net downstream deflection of 32 deg, a downward hub-pitch angle of 6 deg, a 20% increase in blade length (to maintain the same radius as the conventional blade), and a net mass savings of about 50% through decreased shell and spar thicknesses. The pre-alignment may also allow a more straightforward and efficient segmentation of the blade since shear stresses near joints are substantially reduced. Segmenting, in turn, can dramatically reduce costs associated with fabrication, transport and assembly for extreme-scale off-shore systems. The pre-aligned geometric curvature can also help alleviate tower wake effects on the blades since blade tips (where shadow effects can be most problematic) are shifted downstream where the tower wake is weaker. In addition, the portion of the tower that is upstream of the blade tips can be faired with an externally-rotating aerodynamic shroud. Furthermore, the downwind rotor can allow a floating off-shore tri-pod platform to reduce tower weight and yaw-control requirements. A simple economic analysis of the segmented ultralight pre-aligned rotor (SUPAR) concept suggests that the overall system cost savings can be as much as 25%, indicating that more detailed (numerical and experimental) investigations are warranted.

  13. Top Ten Interaction Challenges in Extreme-Scale Visual Analytics

    SciTech Connect (OSTI)

    Wong, Pak C.; Shen, Han-Wei; Chen, Chaomei

    2012-05-31T23:59:59.000Z

    The chapter presents ten selected user interfaces and interaction challenges in extreme-scale visual analytics. The study of visual analytics is often referred to as 'the science of analytical reasoning facilitated by interactive visual interfaces' in the literature. The discussion focuses on the issues of applying visual analytics technologies to extreme-scale scientific and non-scientific data ranging from petabyte to exabyte in sizes. The ten challenges are: in situ interactive analysis, user-driven data reduction, scalability and multi-level hierarchy, representation of evidence and uncertainty, heterogeneous data fusion, data summarization and triage for interactive query, analytics of temporally evolving features, the human bottleneck, design and engineering development, and the Renaissance of conventional wisdom. The discussion addresses concerns that arise from different areas of hardware, software, computation, algorithms, and human factors. The chapter also evaluates the likelihood of success in meeting these challenges in the near future.

  14. Conceptual Design Report for the Extreme Ecosystems Test Chambers

    SciTech Connect (OSTI)

    C. Barnes; J. Beller; K. Caldwell; K. Croft; R. Cherry; W. Landman

    1998-12-01T23:59:59.000Z

    This conceptual design supports the creation of Extreme Ecosystems Test Chambers, which will replicate deep subsurface and subocean environments characterized by high pressure (2,000 psi) and subfreezing to high temperature (-4 to 300 degrees F) with differing chemical and saturation conditions. The design provides a system to support research and development that includes heat transfer, phase change issues in porous media, microbiology in extreme environments, and carbon sequestration and extraction. The initial system design is based on the research needs to support the commercial production of methane hydrates from subsurface sediments. The design provides for three pressure vessels: a Down Hole Test Vessel, a Vertical Multi-phase Test Vessel, and a Horizontal Multi-phase Test Vessel.

  15. Structure of nuclei at extreme values of the isospin

    E-Print Network [OSTI]

    J. Dobaczewski

    1999-01-14T23:59:59.000Z

    Physics of nuclei at extreme values of the isospin is at the focus of present-day nuclear science. Experimentally, thanks to existing and emerging radioactive-ion-beam facilities, we are on the verge of invading the territory of extreme N/Z ratios in an unprecedented way. Theoretically, nuclear exotica represent a formidable challenge for the nuclear many-body theories and their power to predict nuclear properties far from stability. Going to the limits of the nuclear binding is also important for an improvement of our description of normal nuclei from the neighborhood of the beta stability valley. In the present talk, we review several aspects of the present-day mean-field theoretical studies of weakly bound nuclei.

  16. Science at the Theatre - Extreme Science - Promo Video

    SciTech Connect (OSTI)

    Klein, Spencer

    2012-01-01T23:59:59.000Z

    On Feb. 27 at 7 pm at the Berkeley Repertory Theatre, join four Berkeley Lab scientists as they discuss extreme science -- and what it means to you. Topics include: Neutrino hunting in Antarctica. Learn why Spencer Klein goes to the ends of the Earth to search for these ghostly particles. From Chernobyl to Central Asia, Tamas Torok travels the globe to study microbial diversity in extreme environments. Andrew Minor uses the world's most advanced electron microscopes to explore materials at ultrahigh stresses and in harsh environments. And microbes that talk to computers? Caroline Ajo-Franklin is pioneering cellular-electrical connections that could help transform sunlight into fuel. Go here for more information and to view videos of previous Science at the Theater events: http://www.lbl.gov/LBL-PID/fobl/

  17. Science at the Theatre - Extreme Science - Promo Video

    ScienceCinema (OSTI)

    Klein, Spencer

    2013-05-29T23:59:59.000Z

    On Feb. 27 at 7 pm at the Berkeley Repertory Theatre, join four Berkeley Lab scientists as they discuss extreme science -- and what it means to you. Topics include: Neutrino hunting in Antarctica. Learn why Spencer Klein goes to the ends of the Earth to search for these ghostly particles. From Chernobyl to Central Asia, Tamas Torok travels the globe to study microbial diversity in extreme environments. Andrew Minor uses the world's most advanced electron microscopes to explore materials at ultrahigh stresses and in harsh environments. And microbes that talk to computers? Caroline Ajo-Franklin is pioneering cellular-electrical connections that could help transform sunlight into fuel. Go here for more information and to view videos of previous Science at the Theater events: http://www.lbl.gov/LBL-PID/fobl/

  18. New chaos indicators for systems with extremely small Lyapunov exponents

    E-Print Network [OSTI]

    Ken-ichi Okubo; Ken Umeno

    2015-03-18T23:59:59.000Z

    We propose new chaos indicators for systems with extremely small positive Lyapunov exponents. These chaos indicators can firstly detect a sharp transition between the Arnold diffusion regime and the Chirikov diffusion regime of the Froeschl\\'e map and secondly detect chaoticity in systems with zero Lyapunov exponent such as the Boole transformation and the $S$-unimodal function to characterize sub-exponential diffusions.

  19. Exascale Co-design for Modeling Materials in Extreme Environments

    SciTech Connect (OSTI)

    Germann, Timothy C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-07-08T23:59:59.000Z

    Computational materials science has provided great insight into the response of materials under extreme conditions that are difficult to probe experimentally. For example, shock-induced plasticity and phase transformation processes in single-crystal and nanocrystalline metals have been widely studied via large-scale molecular dynamics simulations, and many of these predictions are beginning to be tested at advanced 4th generation light sources such as the Advanced Photon Source (APS) and Linac Coherent Light Source (LCLS). I will describe our simulation predictions and their recent verification at LCLS, outstanding challenges in modeling the response of materials to extreme mechanical and radiation environments, and our efforts to tackle these as part of the multi-institutional, multi-disciplinary Exascale Co-design Center for Materials in Extreme Environments (ExMatEx). ExMatEx has initiated an early and deep collaboration between domain (computational materials) scientists, applied mathematicians, computer scientists, and hardware architects, in order to establish the relationships between algorithms, software stacks, and architectures needed to enable exascale-ready materials science application codes within the next decade. We anticipate that we will be able to exploit hierarchical, heterogeneous architectures to achieve more realistic large-scale simulations with adaptive physics refinement, and are using tractable application scale-bridging proxy application testbeds to assess new approaches and requirements. Such current scale-bridging strategies accumulate (or recompute) a distributed response database from fine-scale calculations, in a top-down rather than bottom-up multiscale approach.

  20. Improved methods for simulating nearly extremal binary black holes

    E-Print Network [OSTI]

    Mark A. Scheel; Matthew Giesler; Daniel A. Hemberger; Geoffrey Lovelace; Kevin Kuper; Michael Boyle; Bela Szilagyi; Lawrence E. Kidder

    2014-12-04T23:59:59.000Z

    Astrophysical black holes could be nearly extremal (that is, rotating nearly as fast as possible); therefore, nearly extremal black holes could be among the binaries that current and future gravitational-wave observatories will detect. Predicting the gravitational waves emitted by merging black holes requires numerical-relativity simulations, but these simulations are especially challenging when one or both holes have mass $m$ and spin $S$ exceeding the Bowen-York limit of $S/m^2=0.93$. We present improved methods that enable us to simulate merging, nearly extremal black holes more robustly and more efficiently. We use these methods to simulate an unequal-mass, precessing binary black hole coalescence, where the larger black hole has $S/m^2=0.99$. We also use these methods to simulate a non-precessing binary black hole coalescence, where both black holes have $S/m^2=0.994$, nearly reaching the Novikov-Thorne upper bound for holes spun up by thin accretion disks. We demonstrate numerical convergence and estimate the numerical errors of the waveforms; we compare numerical waveforms from our simulations with post-Newtonian and effective-one-body waveforms; we compare the evolution of the black-hole masses and spins with analytic predictions; and we explore the effect of increasing spin magnitude on the orbital dynamics (the so-called "orbital hangup" effect).

  1. Simulating merging binary black holes with nearly extremal spins

    SciTech Connect (OSTI)

    Lovelace, Geoffrey [Center for Radiophysics and Space Research, Cornell University, Ithaca, New York, 14853 (United States); Scheel, Mark A.; Szilagyi, Bela [Theoretical Astrophysics 350-17, California Institute of Technology, Pasadena, California 91125 (United States)

    2011-01-15T23:59:59.000Z

    Astrophysically realistic black holes may have spins that are nearly extremal (i.e., close to 1 in dimensionless units). Numerical simulations of binary black holes are important tools both for calibrating analytical templates for gravitational-wave detection and for exploring the nonlinear dynamics of curved spacetime. However, all previous simulations of binary-black-hole inspiral, merger, and ringdown have been limited by an apparently insurmountable barrier: the merging holes' spins could not exceed 0.93, which is still a long way from the maximum possible value in terms of the physical effects of the spin. In this paper, we surpass this limit for the first time, opening the way to explore numerically the behavior of merging, nearly extremal black holes. Specifically, using an improved initial-data method suitable for binary black holes with nearly extremal spins, we simulate the inspiral (through 12.5 orbits), merger and ringdown of two equal-mass black holes with equal spins of magnitude 0.95 antialigned with the orbital angular momentum.

  2. Differential effects of extreme drought on production and respiration: synthesis and modeling analysis

    E-Print Network [OSTI]

    Shi, Z.; Thomey, M. L.; Mowll, W.; Litvak, M.; Brunsell, Nathaniel A.; Collins, S. L.; Pockman, W. T.; Smith, M. D.; Knapp, A. K.; Luo, Y.

    2014-02-04T23:59:59.000Z

    Extremes in climate may severely impact ecosystem structure and function, with both the magnitude and rate of response differing among ecosystem types and processes. We conducted a modeling analysis of the effects of extreme ...

  3. Infrared and Ultraviolet QCD dynamics with quark mass for J=0,1 mesons

    E-Print Network [OSTI]

    Nicholas Souchlas

    2010-06-04T23:59:59.000Z

    By using a previously developed phenomenological kernel for the study of the light quark QCD sector and dynamical chiral symmetry breaking effects we will examine the relative infrared and ultraviolet QCD dynamics for J=0,1 meson properties. For the same reasons we extend and explore a quark mass depended generalization of the kernel in the heavy quark region and we also compare with the original model. The relation between the dynamics of the quark propagator and the effective kernel with the J=0,1 QQ and qQ mesons and quarks Compton size is also discussed.

  4. Highly reproducible and reliable metal/graphene contact by ultraviolet-ozone treatment

    SciTech Connect (OSTI)

    Li, Wei [Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871 (China); Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Hacker, Christina A.; Cheng, Guangjun; Hight Walker, A. R.; Richter, Curt A.; Gundlach, David J., E-mail: david.gundlach@nist.gov, E-mail: liangxl@pku.edu.cn [Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Liang, Yiran; Tian, Boyuan; Liang, Xuelei, E-mail: david.gundlach@nist.gov, E-mail: liangxl@pku.edu.cn; Peng, Lianmao [Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871 (China)

    2014-03-21T23:59:59.000Z

    Resist residue from the device fabrication process is a significant source of contamination at the metal/graphene contact interface. Ultraviolet Ozone (UVO) treatment is proven here, by X-ray photoelectron spectroscopy and Raman measurement, to be an effective way of cleaning the metal/graphene interface. Electrical measurements of devices that were fabricated by using UVO treatment of the metal/graphene contact region show that stable and reproducible low resistance metal/graphene contacts are obtained and the electrical properties of the graphene channel remain unaffected.

  5. Chemo-physical properties of renal capsules under ultraviolet-c exposure

    SciTech Connect (OSTI)

    Baghapour, Sh.; Parvin, P., E-mail: parvin@aut.ac.ir; Mokhtari, S. [Department of Physics, Amirkabir University of Technology, P.O.Box 15875-4413 Tehran (Iran, Islamic Republic of); Reyhani, A.; Mortazavi, S. Z. [Department of Physics, Imam Khomeini International University, P.O.Box 34149-16818 Qazvin (Iran, Islamic Republic of); Amjadi, A. [Department of Physics, Sharif University of Technology, P.O.Box 11365-9567, Tehran (Iran, Islamic Republic of)

    2014-08-07T23:59:59.000Z

    The renal capsule tissue of lamb was irradiated with ultraviolet-C light and the treated samples were analyzed by uniaxial tensile test, dynamic mechanical analysis, attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and contact angle measurements. It was shown that the skin cross-linking is dominant in low doses in accordance with the contact angle assessment. Conversely, the strong bulk degradation takes place at high doses. Similarly, the bulk cross-linking affects the mechanical tests as to enhance the stiffness at low doses, whereas strong degradation occurs at high doses that mainly arises from the strong bulk chain scission.

  6. Total to Selective Extinction Ratios and Visual Extinctions from Ultraviolet Data

    E-Print Network [OSTI]

    Anna Geminale; Piotr Popowski

    2004-09-21T23:59:59.000Z

    We present determinations of the total to selective extinction ratio R_V and visual extinction A_V values for Milky Way stars using ultraviolet color excesses. We extend the analysis of Gnacinski and Sikorski (1999) by using non-equal weights derived from observational errors. We present a detailed discussion of various statistical errors. In addition, we estimate the level of systematic errors by considering different normalization of the extinction curve adopted by Wegner (2002). Our catalog of 782 R_V and A_V values and their errors is available in the electronic form on the World Wide Web.

  7. Towards a better understanding of the structure of nano-minerals at ambient and extreme conditions

    SciTech Connect (OSTI)

    Parise, John B.; Ehm, Lars; Michel, F. Marc [Stony Brook University, Department of Geosciences and Mineral Physics Institute (United States); Antao, Sytle; Chupas, Peter J.; Lee, Peter L.; Martin, C. David; Shastri, Sarvjit [X-ray Science Division, Argonne National Laboratory, Argonne IL 60439 (United States)

    2009-01-29T23:59:59.000Z

    The high-pressure (HP) behavior of nano-crystalline mackinawite (n-FeS) with particle sizes of 6, 7, and 8 nm has been investigated by high-energy X-ray total scattering and pair distribution function analysis. An irreversible first-order structural phase transition from tetragonal mackinawite to orthorhombic FeS-II was observed at about 3 GPa. The transition is induced by the closure of the van-der-Waals gap in the layered mackinawite structure. A grain size effect on the transition pressure and the compressibility was observed. The n-FcS study is an example of a broad class of nano-crystalline minerals where the total scattering (TS) approach provides significant new information on local-, intermediate- and long-range structure. Under extreme conditions, of pressure in this case, straightforward modifications allow quantitative descriptions of the transformations mechanisms.

  8. Ternary particles with extreme N/Z ratios from neutron-induced fission

    SciTech Connect (OSTI)

    Koster, U.; Faust, H.; Friedrichs, T.; Oberstedt, S.; Fioni, G.; Grob, M.; Ahmad, I. J.; Devlin, M.; Heinz, A.; Kondev, F. G.; Lauritsen, T.; Sarantites, D. G.; Siem, S.; Sobotka, L. G.; Sonzogni, A.

    2000-05-16T23:59:59.000Z

    The existing ternary fission models can well reproduce the yields of the most abundant light charged particles. However, these models tend to significantly overestimate the yields of ternary particles with an extreme N/Z ratio: {sup 3}He, {sup 11}Li, {sup 14}Be, etc. The experimental yields of these isotopes were investigated with the recoil separator LOHENGRIN down to a level of 10{sup {minus}10} per fission. Results from the fissioning systems {sup 233}U (n{sub th}, f), {sup 235}U(n{sub th},f), {sup 239}Pu(n{sub th},f) {sup 241}Pu(n{sub th},f) and {sup 245}Cm(n{sub th},f) are presented and the implications for the ternary fission models are discussed.

  9. Absorption cross section of RN and SdS extremal black hole

    E-Print Network [OSTI]

    Sini R; Nijo Varghese; V C Kuriakose

    2008-02-29T23:59:59.000Z

    The nature of scalar wave functions near the horizon of Reissner Nordstrom (RN) extremal and Schwarzschild-de Sitter (SdS) extremal black holes are found using WKB approximation and the effect of reflection of waves from the horizon. The absorption cross section $\\sigma_{abs}$ when RN extremal and SdS extremal black holes placed in a Klein-Gordon field is calculated.

  10. CEES Directorate & Principal Investigators

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

    Argonne National Laboratory Department Chemical Sciences and Engineering Division Area of Focus Electrochemical energy storage Professional Summary Senior Investigators...

  11. Basic Research Needs for Materials Under Extreme Environments. Report of the Basic Energy Sciences Workshop on Materials Under Extreme Environments, June 11-13, 2007

    SciTech Connect (OSTI)

    Wadsworth, J.; Crabtree, G. W.; Hemley, R. J.; Falcone, R.; Robertson, I.; Stringer, J.; Tortorelli, P.; Gray, G. T.; Nicol, M.; Lehr, J.; Tozer, S. W.; Diaz de la Rubia, T.; Fitzsimmons, T.; Vetrano, J. S.; Ashton, C. L.; Kitts, S.; Landson, C.; Campbell, B.; Gruzalski, G.; Stevens, D.

    2008-02-01T23:59:59.000Z

    To evaluate the potential for developing revolutionary new materials that will meet demanding future energy requirements that expose materials to environmental extremes.

  12. Statistics of extremes in hydrology Richard W. Katz a,*, Marc B. Parlange b

    E-Print Network [OSTI]

    Katz, Richard

    Statistics of extremes in hydrology Richard W. Katz a,*, Marc B. Parlange b , Philippe Naveau c Abstract The statistics of extremes have played an important role in engineering practice for water resources design and management. How recent developments in the statistical theory of extreme values can

  13. Extreme Value GARCH modelling with Bayesian Xin Zhao, Les Oxley, Carl Scarrott and Marco Reale

    E-Print Network [OSTI]

    Hickman, Mark

    Extreme Value GARCH modelling with Bayesian Inference Xin Zhao, Les Oxley, Carl Scarrott and Marco Reale No: 05/2009 #12;2 WORKING PAPER No: 05/2009 Extreme Value GARCH modelling with Bayesian inference, GEV-GARCH, is developed by implementing the GARCH volatility mechanism in these extreme value model

  14. Method for synthesizing extremely high-temperature melting materials

    DOE Patents [OSTI]

    Saboungi, Marie-Louise (Chicago, IL); Glorieux, Benoit (Perpignan, FR)

    2007-11-06T23:59:59.000Z

    The invention relates to a method of synthesizing high-temperature melting materials. More specifically the invention relates to a containerless method of synthesizing very high temperature melting materials such as carbides and transition-metal, lanthanide and actinide oxides, using an aerodynamic levitator and a laser. The object of the invention is to provide a method for synthesizing extremely high-temperature melting materials that are otherwise difficult to produce, without the use of containers, allowing the manipulation of the phase (amorphous/crystalline/metastable) and permitting changes of the environment such as different gaseous compositions.

  15. Method For Synthesizing Extremely High-Temperature Melting Materials

    DOE Patents [OSTI]

    Saboungi, Marie-Louise (Chicago, IL); Glorieux, Benoit (Perpignan, FR)

    2005-11-22T23:59:59.000Z

    The invention relates to a method of synthesizing high-temperature melting materials. More specifically the invention relates to a containerless method of synthesizing very high temperature melting materials such as borides, carbides and transition-metal, lanthanide and actinide oxides, using an Aerodynamic Levitator and a laser. The object of the invention is to provide a method for synthesizing extremely high-temperature melting materials that are otherwise difficult to produce, without the use of containers, allowing the manipulation of the phase (amorphous/crystalline/metastable) and permitting changes of the environment such as different gaseous compositions.

  16. Solidification at the High and Low Rate Extreme

    SciTech Connect (OSTI)

    Halim Meco

    2004-12-19T23:59:59.000Z

    The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt-pool oscillation may be the dominant factor governing the onset of unsteady thermal conditions accompanied by varying amounts of crystalline nucleation observed near the lower limit. At high quench-wheel velocities, the influence of these oscillations is minimal due to very short melt-pool residence times. However, microstructural evidence suggests that the entrapment of gas pockets at the wheel-metal interface plays a critical role in establishing the upper rate limit. An observed transition in wheel-side surface character with increasing melt-spinning rate supports this conclusion.

  17. Supercomputers: Extreme Computing at the National Labs | Department of

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed off Energy.gov. Are you sure you wantJoin us for|Idaho |Energy Supercomputers: Extreme Computing

  18. Scientists use world's fastest computer to model materials under extreme

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol HomeFacebook Twitter PrincipalfuelTorusconditions Materials under extreme

  19. Extreme Balance of System Hardware Cost Reduction | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport in Representative Geologic Media |Efficient Solutions for NewServices »Extreme

  20. ultraviolet | EMSL

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

    and early disease diagnostic applications. Citation: Lee AC, D Du, B Chen, CK Heng, TM Lim, and Y Lin.2014."Electrochemical detection of leukemia oncogenes using...

  1. EMSL - ultraviolet

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

    class"field-item even" property"schema:citation">Lee AC, D Du, B Chen, CK Heng, TM Lim, and Y Lin.2014."Electrochemical detection of leukemia oncogenes using...

  2. Laser Desorption Postionization Mass Spectrometry of Antibiotic-Treated Bacterial Biofilms using Tunable Vacuum Ultraviolet Radiation

    SciTech Connect (OSTI)

    Gasper, Gerald L.; Takahashi, Lynelle K.; Zhou, Jia; Ahmed, Musahid; Moore, Jerry F.; Hanley, Luke

    2010-08-04T23:59:59.000Z

    Laser desorption postionization mass spectrometry (LDPI-MS) with 8.0 ? 12.5 eV vacuum ultraviolet synchrotron radiation is used to single photon ionize antibiotics andextracellular neutrals that are laser desorbed both neat and from intact bacterial biofilms. Neat antibiotics are optimally detected using 10.5 eV LDPI-MS, but can be ionized using 8.0 eV radiation, in agreement with prior work using 7.87 eV LDPI-MS. Tunable vacuum ultraviolet radiation also postionizes laser desorbed neutrals of antibiotics and extracellular material from within intact bacterial biofilms. Different extracellular material is observed by LDPI-MS in response to rifampicin or trimethoprim antibiotic treatment. Once again, 10.5 eV LDPI-MS displays the optimum trade-off between improved sensitivity and minimum fragmentation. Higher energy photons at 12.5 eV produce significant parent ion signal, but fragment intensity and other low mass ions are also enhanced. No matrix is added to enhance desorption, which is performed at peak power densities insufficient to directly produce ions, thus allowing observation of true VUV postionization mass spectra of antibiotic treated biofilms.

  3. Support of the balloon-borne ultraviolet stellar spectrograph. Final report

    SciTech Connect (OSTI)

    Timothy, J.G.

    1986-05-01T23:59:59.000Z

    A (256 x 1024)-pixel imaging ultraviolet Multi-mode Microchannel Array (MAMA) detector system for flight was fabricated, evaluated, and environmentally tested for flight on the Balloon Borne Ultraviolet Stellar Spectrograph (BUSS). The goal of the program was to replace the existing SEC Vidicon with the pulse-counting MAMA detector in order to, first, improve the overall sensitivity of the BUSS telescope and spectrograph for observations of stars down to m sub v = 7 and fainter, and, second, to improve the spectral resolution and wavelength accuracy by eliminating the image drifts in the Vidicon caused by magnetic field effects. A sealed MAMA detector tube structure employing a remotely processed photocathode mounted on a window in proximity focus with the front face of the MCP was developed to avoid contamination produced by a noisy and unstable device. The configuration of the BUSS detector system in its flight ready configuration is shown. The quantum efficiency curve for the semi-transparent Cs/sub 2/Te photocathode is also shown.

  4. Constraints to the magnetospheric properties of T Tauri stars - II. The Mg II ultraviolet feature

    E-Print Network [OSTI]

    Lopez-Martinez, Fatima

    2015-01-01T23:59:59.000Z

    The atmospheric structure of T Tauri Stars (TTSs) and its connection with the large scale outflow is poorly known. Neither the effect of the magnetically mediated inter- action between the star and the disc in the stellar atmosphere is well understood. The Mg II multiplet is a fundamental tracer of TTSs atmospheres and outflows, and is the strongest feature in the near-ultraviolet spectrum of TTSs. The International Ultraviolet Explorer and Hubble Space Telescope data archives provide a unique set to study the main physical compounds contributing to the line profile and to derive the properties of the line formation region. The Mg II profiles of 44 TTSs with resolution 13,000 to 30,000 are available in these archives. In this work, we use this data set to measure the main observables: flux, broadening, asymmetry, terminal velocity of the outflow, and the velocity of the Discrete Absorption Components. For some few sources repeated observations are available and variability has been studied. There is a warm wi...

  5. Melanocytes can absorb ultraviolet radiation (UVR) and survive con-siderable genotoxic stress. The skin is the main barrier to the exter-

    E-Print Network [OSTI]

    Cai, Long

    to the appearance of skin and provide protection from damage by ultraviolet radiation. Pigmentation mutantsMelanocytes can absorb ultraviolet radiation (UVR) and survive con- siderable genotoxic stress. Thisreviewsummarizeshowpigmentationisregulatedatthemolecu- lar level and how the tanning response provides protection against dam- age and skin cancer. We

  6. Near Horizon Structure of Extremal Vanishing Horizon Black Holes

    E-Print Network [OSTI]

    Sadeghian, S; Vahidinia, M H; Yavartanoo, H

    2015-01-01T23:59:59.000Z

    We study the near horizon structure of Extremal Vanishing Horizon (EVH) black holes, extremal black holes with vanishing horizon area with a vanishing one-cycle on the horizon. We construct the most general near horizon EVH and near-EVH ansatz for the metric and other fields, like dilaton and gauge fields which may be present in the theory. We prove that (1) the near horizon EVH geometry for generic gravity theory in generic dimension has a three dimensional maximally symmetric subspace; (2) if the matter fields of the theory satisfy strong energy condition either this 3d part is AdS$_3$, or the solution is a direct product of a locally 3d flat space and a $d-3$ dimensional part; (3) these results extend to the near horizon geometry of near-EVH black holes, for which the AdS$_3$ part is replaced with BTZ geometry. We present some specific near horizon EVH geometries in 3, 4 and 5 dimensions for which there is a classification. We also briefly discuss implications of these generic results for generic (gauged) ...

  7. Damage detection in mechanical structures using extreme value statistic.

    SciTech Connect (OSTI)

    Worden, K.; Allen, D. W. (David W.); Sohn, H. (Hoon); Farrar, C. R. (Charles R.)

    2002-01-01T23:59:59.000Z

    The first and most important objective of any damage identification algorithms is to ascertain with confidence if damage is present or not. Many methods have been proposed for damage detection based on ideas of novelty detection founded in pattern recognition and multivariate statistics. The philosophy of novelty detection is simple. Features are first extracted from a baseline system to be monitored, and subsequent data are then compared to see if the new features are outliers, which significantly depart from the rest of population. In damage diagnosis problems, the assumption is that outliers are generated from a damaged condition of the monitored system. This damage classification necessitates the establishment of a decision boundary. Choosing this threshold value is often based on the assumption that the parent distribution of data is Gaussian in nature. While the problem of novelty detection focuses attention on the outlier or extreme values of the data i.e. those points in the tails of the distribution, the threshold selection using the normality assumption weighs the central population of data. Therefore, this normality assumption might impose potentially misleading behavior on damage classification, and is likely to lead the damage diagnosis astray. In this paper, extreme value statistics is integrated with the novelty detection to specifically model the tails of the distribution of interest. Finally, the proposed technique is demonstrated on simulated numerical data and time series data measured from an eight degree-of-freedom spring-mass system.

  8. Radiation from Bodies with Extreme Acceleration II: Kinematics

    E-Print Network [OSTI]

    Ulrich H. Gerlach

    2003-07-10T23:59:59.000Z

    When applied to a dipole source subjected to acceleration which is violent and long lasting (``extreme acceleration''), Maxwell's equations predict radiative power which augments Larmor's classical radiation formula by a nontrivial amount. The physical assumptions behind this result are made possible by the kinematics of a system of geometrical clocks whose tickings are controlled by cavities which are expanding inertially. For the purpose of measuring the radiation from such a source we take advantage of the physical validity of a spacetime coordinate framework (``inertially expanding frame'') based on such clocks. They are compatible and commensurable with the accelerated clocks of the accelerated source. By contrast, a common Lorentz frame with its mutually static clocks won't do: it lacks that commensurability. Inertially expanding clocks give a physicist a window into the frame of a source with extreme acceleration. He thus can locate that source and measure radiation from it without being subjected to such acceleration himself. The conclusion is that inertially expanding reference frames reveal qualitatively distinct aspects of nature which would not be accessible if static inertial frames were the only admissible frames.

  9. Explicit Integration of Extremely Stiff Reaction Networks: Partial Equilibrium Methods

    SciTech Connect (OSTI)

    Guidry, Mike W [ORNL; Billings, J. J. [Oak Ridge National Laboratory (ORNL); Hix, William Raphael [ORNL

    2013-01-01T23:59:59.000Z

    In two preceding papers [1,2] we have shown that, when reaction networks are well removed from equilibrium, explicit asymptotic and quasi-steady-state approximations can give algebraically stabilized integration schemes that rival standard implicit methods in accuracy and speed for extremely stiff systems. However, we also showed that these explicit methods remain accurate but are no longer competitive in speed as the network approaches equilibrium. In this paper we analyze this failure and show that it is associated with the presence of fast equilibration timescales that neither asymptotic nor quasi-steady-state approximations are able to remove efficiently from the numerical integration. Based on this understanding, we develop a partial equilibrium method to deal effectively with the new partial equilibrium methods, give an integration scheme that plausibly can deal with the stiffest networks, even in the approach to equilibrium, with accuracy and speed competitive with that of implicit methods. Thus we demonstrate that algebraically stabilized explicit methods may offer alternatives to implicit integration of even extremely stiff systems, and that these methods may permit integration of much larger networks than have been feasible previously in a variety of fields.

  10. Geometric Constrained Variational Calculus. I. - Piecewise smooth extremals

    E-Print Network [OSTI]

    Enrico Massa; Danilo Bruno; Gianvittorio Luria; Enrico Pagani

    2015-03-30T23:59:59.000Z

    A geometric setup for constrained variational calculus is presented. The analysis deals with the study of the extremals of an action functional defined on piecewise differentiable curves, subject to differentiable, non-holonomic constraints. Special attention is paid to the tensorial aspects of the theory. As far as the kinematical foundations are concerned, a fully covariant scheme is developed through the introduction of the concept of infinitesimal control. The standard classification of the extremals into normal and abnormal ones is discussed, pointing out the existence of an algebraic algorithm assigning to each admissible curve a corresponding abnormality index, related to the co-rank of a suitable linear map. Attention is then shifted to the study of the first variation of the action functional. The analysis includes a revisitation of Pontryagin's equations and of the Lagrange multipliers method, as well as a reformulation of Pontryagin's algorithm in hamiltonian terms. The analysis is completed by a general result, concerning the existence of finite deformations with fixed endpoints.

  11. Adapting to Climate ChangeAdapting to Climate Change ExtremeExtreme Water Levels, Invasive Species andWater Levels, Invasive Species and

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Adapting to Climate ChangeAdapting to Climate Change ­­ ExtremeExtreme Water Levels, Invasive." IPCC Risk management is the framework to discuss adaptation to climate change impacts. Risk The Water Resources Working Group will assess and synthesize climate change impacts to Wisconsin's water

  12. Published in Proceedings of the XL2003 (Response of Structures to Extreme Loading) Conference, Toronto, August 2003. EFFICIENT MODELS FOR WIND TURBINE EXTREME LOADS

    E-Print Network [OSTI]

    Manuel, Lance

    , Toronto, August 2003. EFFICIENT MODELS FOR WIND TURBINE EXTREME LOADS USING INVERSE RELIABILITY K, USA ABSTRACT The reliability of wind turbines against extreme loads is the focus of this study loads for a 600kW three-bladed horizontal-axis wind turbine. Only operating loads ­ here, flapwise (out

  13. Theory of extreme correlations using canonical Fermions and path integrals

    SciTech Connect (OSTI)

    Shastry, B. Sriram, E-mail: sriram@physics.ucsc.edu

    2014-04-15T23:59:59.000Z

    The  t–J  model is studied using a novel and rigorous mapping of the Gutzwiller projected electrons, in terms of canonical electrons. The mapping has considerable similarity to the Dyson–Maleev transformation relating spin operators to canonical Bosons. This representation gives rise to a non Hermitian quantum theory, characterized by minimal redundancies. A path integral representation of the canonical theory is given. Using it, the salient results of the extremely correlated Fermi liquid (ECFL) theory, including the previously found Schwinger equations of motion, are easily rederived. Further, a transparent physical interpretation of the previously introduced auxiliary Greens function and the ‘caparison factor’, is obtained. The low energy electron spectral function in this theory, with a strong intrinsic asymmetry, is summarized in terms of a few expansion coefficients. These include an important emergent energy scale ?{sub 0} that shrinks to zero on approaching the insulating state, thereby making it difficult to access the underlying very low energy Fermi liquid behavior. The scaled low frequency ECFL spectral function, related simply to the Fano line shape, has a peculiar energy dependence unlike that of a Lorentzian. The resulting energy dispersion obtained by maximization is a hybrid of a massive and a massless Dirac spectrum E{sub Q}{sup ?}??Q??(?{sub 0}{sup 2}+Q{sup 2}), where the vanishing of Q, a momentum type variable, locates the kink minimum. Therefore the quasiparticle velocity interpolates between (??1) over a width ?{sub 0} on the two sides of Q=0, implying a kink there that strongly resembles a prominent low energy feature seen in angle resolved photoemission spectra (ARPES) of cuprate materials. We also propose novel ways of analyzing the ARPES data to isolate the predicted asymmetry between particle and hole excitations. -- Highlights: •Spectral function of the Extremely Correlated Fermi Liquid theory at low energy. •Electronic origin of low energy kinks in energy dispersion. •Non Hermitian representation of Gutzwiller projected electrons. •Analogy with Dyson–Maleev representation of spins. •Path integral formulation of extremely correlated electrons.

  14. High efficiency single Ag nanowire/p-GaN substrate Schottky junction-based ultraviolet light emitting diodes

    E-Print Network [OSTI]

    Wu, Y.; Hasan, T.; Li, X.; Xu, P.; Wang, Y.; Shen, X.; Liu, X.; Yang, Q.

    2015-02-05T23:59:59.000Z

    We report a high efficiency single Ag nanowire (NW)/p-GaN substrate Schottky junction-based ultraviolet light emitting diode (UV-LED). The device demonstrates deep UV free exciton electroluminescence at 362.5?nm. The dominant emission, detectable...

  15. Self-heating in a GaN based heterostructure field effect transistor: Ultraviolet and visible Raman measurements and simulations

    E-Print Network [OSTI]

    Holtz, Mark

    Self-heating in a GaN based heterostructure field effect transistor: Ultraviolet and visible Raman online 8 December 2006 We report direct self-heating measurements for AlGaN/GaN heterostructure field density can be commensurately high, collisional energy loss from electrons to the crystal leads to self-heating

  16. Interaction of methanol and water on MgO,,100... studied by ultraviolet photoelectron and metastable impact electron spectroscopies

    E-Print Network [OSTI]

    Goodman, Wayne

    Interaction of methanol and water on MgO,,100... studied by ultraviolet photoelectron; accepted 27 October 1998 The coadsorption of methanol (CH3OH) and water (D2O) on the MgO 100 /Mo 100 photoelectron spectroscopy UPS HeI , and by thermal programmed desorption TPD . Methanol wets the MgO surface

  17. Devices useful for vacuum ultraviolet beam characterization including a movable stage with a transmission grating and image detector

    DOE Patents [OSTI]

    Gessner, Oliver; Kornilov, Oleg A; Wilcox, Russell B

    2013-10-29T23:59:59.000Z

    The invention provides for a device comprising an apparatus comprising (a) a transmission grating capable of diffracting a photon beam into a diffracted photon output, and (b) an image detector capable of detecting the diffracted photon output. The device is useful for measuring the spatial profile and diffraction pattern of a photon beam, such as a vacuum ultraviolet (VUV) beam.

  18. DO THE INFRARED EMISSION FEATURES NEED ULTRAVIOLET EXCITATION? THE POLYCYCLIC AROMATIC HYDROCARBON MODEL IN UV-POOR REFLECTION NEBULAE

    E-Print Network [OSTI]

    Draine, Bruce T.

    '' PAHs in reflection nebulae near stars as cool as Teff ¼ 3000 K can result in observable emis- sion at 6DO THE INFRARED EMISSION FEATURES NEED ULTRAVIOLET EXCITATION? THE POLYCYCLIC AROMATIC HYDROCARBON MODEL IN UV-POOR REFLECTION NEBULAE Aigen Li and B. T. Draine Department of Astrophysical Sciences

  19. Vacuum ultraviolet mass-analyzed threshold ionization spectroscopy of benzene: Vibrational analysis of C6H6

    E-Print Network [OSTI]

    Kim, Myung Soo

    Vacuum ultraviolet mass-analyzed threshold ionization spectroscopy of benzene: Vibrational analysis-photon spectra agrees with the previous suggestion that the geometry of benzene cation in the ground electronic. INTRODUCTION Benzene cation has been the focus of an intensive re- search effort, both experimental1

  20. Effects of PGF{sub 2{alpha}} on human melanocytes and regulation of the FP receptor by ultraviolet radiation

    SciTech Connect (OSTI)

    Scott, Glynis [Department of Dermatology, University of Rochester School of Medicine, Box 697, 601 Elmwood Avenue, Rochester, NY 14642 (United States)]. E-mail: Glynis_Scott@urmc.rochester.edu; Jacobs, Stacey [Department of Dermatology, University of Rochester School of Medicine, Box 697, 601 Elmwood Avenue, Rochester, NY 14642 (United States); Leopardi, Sonya [Department of Dermatology, University of Rochester School of Medicine, Box 697, 601 Elmwood Avenue, Rochester, NY 14642 (United States); Anthony, Frank A. [Schering-Plough HealthCare Products Inc., Memphis TN (United States); Learn, Doug [Charles River DDS, Argus Division, Horsham, PA (United States); Malaviya, Rama [University of Medicine and Dentistry, RWJMS, New Brunswick, NJ (United States); Pentland, Alice [Department of Dermatology, University of Rochester School of Medicine, Box 697, 601 Elmwood Avenue, Rochester, NY 14642 (United States)

    2005-04-01T23:59:59.000Z

    Prostaglandins are potent lipid hormones that activate multiple signaling pathways resulting in regulation of cellular growth, differentiation, and apoptosis. In the skin, prostaglandins are rapidly released by keratinocytes following ultraviolet radiation and are chronically present in inflammatory skin lesions. We have shown previously that melanocytes, which provide photoprotection to keratinocytes through the production of melanin, express several receptors for prostaglandins, including the PGE{sub 2} receptors EP{sub 1} and EP{sub 3} and the PGF{sub 2{alpha}} receptor FP, and that PGF{sub 2{alpha}} stimulates melanocyte dendricity. We now show that PGF{sub 2{alpha}} stimulates the activity and expression of tyrosinase, the rate-limiting enzyme in melanin synthesis. Analysis of FP receptor regulation showed that the FP receptor is regulated by ultraviolet radiation in melanocytes in vitro and in human skin in vivo. We also show that ultraviolet irradiation stimulates production of PGF{sub 2{alpha}} by melanocytes. These results show that PGF{sub 2{alpha}} binding to the FP receptor activates signals that stimulate a differentiated phenotype (dendricity and pigmentation) in melanocytes. The regulation of the FP receptor and the stimulation of production of PGF{sub 2{alpha}} in melanocytes in response to ultraviolet radiation suggest that PGF{sub 2{alpha}} could act as an autocrine factor for melanocyte differentiation.

  1. Distinct Ultraviolet-Signaling Pathways in Bean Leaves. DNA Damage Is Associated with -1,3-Glucanase Gene

    E-Print Network [OSTI]

    Leubner, Gerhard

    Distinct Ultraviolet-Signaling Pathways in Bean Leaves. DNA Damage Is Associated with -1 (UV-B; 280­320 nm) radiation in primary leaves of French bean (Phaseolus vulgaris to the expression of bean class I Glu ( Glu I). In contrast to other proteins of the family of pathogenesis

  2. Three-dimensional hydrodynamical CO5BOLD model atmospheres of red giant stars. IV. Oxygen diagnostics in extremely metal-poor red giants with infrared OH lines

    E-Print Network [OSTI]

    Dobrovolskas, V; Bonifacio, P; Caffau, E; Ludwig, H -G; Steffen, M; Spite, M

    2015-01-01T23:59:59.000Z

    Context. Although oxygen is an important tracer of Galactic chemical evolution, measurements of its abundance in the atmospheres of the oldest Galactic stars are still scarce and rather imprecise. At the lowest end of the metallicity scale, oxygen can only be measured in giant stars and in most of cases such measurements rely on a single forbidden [O I] 630 nm line that is very weak and frequently blended with telluric lines. Although molecular OH lines located in the ultraviolet and infrared could also be used for the diagnostics, oxygen abundances obtained from the OH lines and the [O I] 630 nm line are usually discrepant to a level of ~0.3-0.4 dex. Aims. We study the influence of convection on the formation of the infrared (IR) OH lines and the forbidden [O I] 630 nm line in the atmospheres of extremely metal-poor (EMP) red giant stars. Methods. We used high-resolution and high signal-to-noise ratio spectra of four EMP red giant stars obtained with the VLT CRIRES spectrograph. For each EMP star, 4-14 IR OH...

  3. TESTING THE APODIZED PUPIL LYOT CORONAGRAPH ON THE LABORATORY FOR ADAPTIVE OPTICS EXTREME ADAPTIVE OPTICS TESTBED

    SciTech Connect (OSTI)

    Thomas, Sandrine J.; Dillon, Daren; Gavel, Donald [Laboratory for Adaptive Optics, University of California/Lick Observatories, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Soummer, Remi [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Macintosh, Bruce [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550 (United States); Sivaramakrishnan, Anand, E-mail: sthomas@ucolick.org, E-mail: dillon@ucolick.org, E-mail: gavel@ucolick.org, E-mail: soummer@stsci.edu, E-mail: macintosh1@mail.llnl.gov, E-mail: anand@amnh.org [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024 (United States)

    2011-10-15T23:59:59.000Z

    We present testbed results of the Apodized Pupil Lyot Coronagraph (APLC) at the Laboratory for Adaptive Optics (LAO). These results are part of the validation and tests of the coronagraph and of the Extreme Adaptive Optics (ExAO) for the Gemini Planet Imager (GPI). The apodizer component is manufactured with a halftone technique using black chrome microdots on glass. Testing this APLC (like any other coronagraph) requires extremely good wavefront correction, which is obtained to the 1 nm rms level using the microelectricalmechanical systems (MEMS) technology, on the ExAO visible testbed of the LAO at the University of Santa Cruz. We used an APLC coronagraph without central obstruction, both with a reference super-polished flat mirror and with the MEMS to obtain one of the first images of a dark zone in a coronagraphic image with classical adaptive optics using a MEMS deformable mirror (without involving dark hole algorithms). This was done as a complementary test to the GPI coronagraph testbed at American Museum of Natural History, which studied the coronagraph itself without wavefront correction. Because we needed a full aperture, the coronagraph design is very different from the GPI design. We also tested a coronagraph with central obstruction similar to that of GPI. We investigated the performance of the APLC coronagraph and more particularly the effect of the apodizer profile accuracy on the contrast. Finally, we compared the resulting contrast to predictions made with a wavefront propagation model of the testbed to understand the effects of phase and amplitude errors on the final contrast.

  4. BAL QSOs AND EXTREME UFOs: THE EDDINGTON CONNECTION

    SciTech Connect (OSTI)

    Zubovas, Kastytis; King, Andrew, E-mail: kastytis.zubovas@ftmc.lt [Theoretical Astrophysics Group, University of Leicester, Leicester LE1 7RH (United Kingdom)

    2013-05-20T23:59:59.000Z

    We suggest a common physical origin connecting the fast, highly ionized winds (UFOs) seen in nearby active galactic nuclei (AGNs), and the slower and less ionized winds of broad absorption line (BAL) QSOs. The primary difference is the mass-loss rate in the wind, which is ultimately determined by the rate at which mass is fed toward the central supermassive black hole (SMBH) on large scales. This is below the Eddington accretion rate in most UFOs, and slightly super-Eddington in extreme UFOs such as PG1211+143, but ranges up to {approx}10-50 times this in BAL QSOs. For UFOs this implies black hole accretion rates and wind mass-loss rates which are at most comparable to Eddington, giving fast, highly ionized winds. In contrast, BAL QSO black holes have mildly super-Eddington accretion rates, and drive winds whose mass-loss rates are significantly super-Eddington, and so are slower and less ionized. This picture correctly predicts the velocities and ionization states of the observed winds, including the recently discovered one in SDSS J1106+1939. We suggest that luminous AGNs may evolve through a sequence from BAL QSO through LoBAL to UFO-producing Seyfert or quasar as their Eddington factors drop during the decay of a bright accretion event. LoBALs correspond to a short-lived stage in which the AGN radiation pressure largely evacuates the ionization cone, but before the large-scale accretion rate has dropped to the Eddington value. We show that sub-Eddington wind rates would produce an M-{sigma} relation lying above that observed. We conclude that significant SMBH mass growth must occur in super-Eddington phases, either as BAL QSOs, extreme UFOs, or obscured from direct observation.

  5. Material dynamics under extreme conditions of pressure and strain rate

    SciTech Connect (OSTI)

    Remington, B A; Allen, P; Bringa, E; Hawreliak, J; Ho, D; Lorenz, K T; Lorenzana, H; Meyers, M A; Pollaine, S W; Rosolankova, K; Sadik, B; Schneider, M S; Swift, D; Wark, J; Yaakobi, B

    2005-09-06T23:59:59.000Z

    Solid state experiments at extreme pressures (10-100 GPa) and strain rates ({approx}10{sup 6}-10{sup 8}s{sup -1}) are being developed on high-energy laser facilities, and offer the possibility for exploring new regimes of materials science. These extreme solid-state conditions can be accessed with either shock loading or with a quasi-isentropic ramped pressure drive. Velocity interferometer measurements establish the high pressure conditions. Constitutive models for solid-state strength under these conditions are tested by comparing 2D continuum simulations with experiments measuring perturbation growth due to the Rayleigh-Taylor instability in solid-state samples. Lattice compression, phase, and temperature are deduced from extended x-ray absorption fine structure (EXAFS) measurements, from which the shock-induced {alpha}-{omega} phase transition in Ti and the {alpha}-{var_epsilon} phase transition in Fe are inferred to occur on sub-nanosec time scales. Time resolved lattice response and phase can also be measured with dynamic x-ray diffraction measurements, where the elastic-plastic (1D-3D) lattice relaxation in shocked Cu is shown to occur promptly (< 1 ns). Subsequent large-scale molecular dynamics (MD) simulations elucidate the microscopic dynamics that underlie the 3D lattice relaxation. Deformation mechanisms are identified by examining the residual microstructure in recovered samples. The slip-twinning threshold in single-crystal Cu shocked along the [001] direction is shown to occur at shock strengths of {approx}20 GPa, whereas the corresponding transition for Cu shocked along the [134] direction occurs at higher shock strengths. This slip-twinning threshold also depends on the stacking fault energy (SFE), being lower for low SFE materials. Designs have been developed for achieving much higher pressures, P > 1000 GPa, in the solid state on the National Ignition Facility (NIF) laser.

  6. Extreme multiplex spectroscopy at wide-field 4-m telescopes

    E-Print Network [OSTI]

    Robert Content; Tom Shanks

    2008-08-18T23:59:59.000Z

    We describe the design and science case for a spectrograph for the prime focus of classical 4-m wide-field telescopes that can deliver at least 4000 MOS slits over a 1 degree field. This extreme multiplex capability means that 25000 galaxy redshifts can be measured in a single night, opening up the possibilities for large galaxy redshift surveys out to z~0.7 and beyond for the purpose of measuring the Baryon Acoustic Oscillation (BAO) scale and for many other science goals. The design features four cloned spectrographs and exploits the exclusive possibility of tiling the focal plane of wide-field 4-m telescopes with CCDs for multi-object spectroscopic purposes. In ~200 night projects, such spectrographs have the potential to make galaxy redshift surveys of ~6 million galaxies over a wide redshift range and thus may provide a low-cost alternative to other survey routes such as WFMOS and SKA. Two of these extreme multiplex spectrographs are currently being designed for the AAT (NG1dF) and Calar Alto (XMS) 4-m class telescopes. NG2dF, a larger version for the AAT 2 degree field, would have 12 clones and at least 12000 slits. The clones use a transparent design including a grism in which all optics are smaller than the clone square subfield so that the clones can be tightly packed with little gaps between the contiguous fields. Only low cost glasses are used; the variations in chromatic aberrations between bands are compensated by changing one or two of the lenses adjacent to the grism. The total weight and length is smaller with a few clones than a unique spectrograph which makes it feasible to place the spectrograph at the prime focus.

  7. Mössbauer Spectroscopy Investigation and Hydrodesulfurization...

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

    Spectroscopy Investigation and Hydrodesulfurization Properties of Iron–nickel Phosphide Catalysts. Mössbauer Spectroscopy Investigation and...

  8. Delayed Ultrafast X-ray Auger Probing (DUXAP) of Nucleobase Ultraviolet Photoprotection

    E-Print Network [OSTI]

    McFarland, B K; Miyabe, S; Tarantelli, F; Aguilar, A; Berrah, N; Bostedt, C; Bozek, J; Bucksbaum, P H; Castagna, J C; Coffee, R; Cryan, J; Fang, L; Feifel, R; Gaffney, K; Glownia, J; Martinez, T; Mucke, M; Murphy, B; Natan, A; Osipov, T; Petrovic, V; Schorb, S; Schultz, Th; Spector, L; Swiggers, M; Tenney, I; Wang, S; White, W; White, J; Gühr, M

    2013-01-01T23:59:59.000Z

    We present a new method for ultrafast spectroscopy of molecular photoexcited dynamics. The technique uses a pair of femtosecond pulses: a photoexcitation pulse initiating excited state dynamics followed by a soft x-ray (SXR) probe pulse that core ionizes certain atoms inside the molecule. We observe the Auger decay of the core hole as a function of delay between the photoexcitation and SXR pulses. The core hole decay is particularly sensitive to the local valence electrons near the core and shows new types of propensity rules, compared to dipole selection rules in SXR absorption or emission spectroscopy. We apply the delayed ultrafast x-ray Auger probing (DUXAP) method to the specific problem of nucleobase photoprotection to demonstrate its potential. The ultraviolet photoexcited \\pi\\pi* states of nucleobases are prone to chemical reactions with neighboring bases. To avoid this, the single molecules funnel the \\pi\\pi* population to lower lying electronic states on an ultrafast timescale under violation of the...

  9. Ultraviolet stimulated electron source for use with low energy plasma instrument calibration

    SciTech Connect (OSTI)

    Henderson, Kevin; Harper, Ron; Funsten, Herb; MacDonald, Elizabeth [Space Science and Applications, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2012-07-15T23:59:59.000Z

    We have developed and demonstrated a versatile, compact electron source that can produce a mono-energetic electron beam up to 50 mm in diameter from 0.1 to 30 keV with an energy spread of <10 eV. By illuminating a metal cathode plate with a single near ultraviolet light emitting diode, a spatially uniform electron beam with 15% variation over 1 cm{sup 2} can be generated. A uniform electric field in front of the cathode surface accelerates the electrons into a beam with an angular divergence of <1 Degree-Sign at 1 keV. The beam intensity can be controlled from 10 to 10{sup 9} electrons cm{sup -2} s{sup -1}.

  10. Dynamics of the solar chromosphere. V. High-frequency modulation in ultraviolet image sequences from TRACE

    E-Print Network [OSTI]

    A. G. de Wijn; R. J. Rutten; T. D. Tarbell

    2007-06-13T23:59:59.000Z

    We search for signatures of high-frequency oscillations in the upper solar photosphere and low chromosphere in the context of acoustic heating of outer stellar atmospheres. We use ultraviolet image sequences of a quiet center-disk area from the Transition Region and Coronal Explorer (TRACE) mission which were taken with strict cadence regularity. The latter permits more reliable high-frequency diagnosis than in earlier work. Spatial Fourier power maps, spatially averaged coherence and phase-difference spectra, and spatio-temporal k-f decompositions all contain high-frequency features that at first sight seem of considerable intrinsic interest but actually are more likely to represent artifacts of different nature. Spatially averaged phase difference measurement provides the most sensitive diagnostic and indicates the presence of acoustic modulation up to f=20 mHz (periods down to 50 seconds) in internetwork areas.

  11. Functionalization of carbon nanotubes by argon plasma-assisted ultraviolet grafting

    SciTech Connect (OSTI)

    Yan, Y.H.; Chan-Park, M.B.; Zhou, Q.; Li, C.M.; Yue, C.Y. [School of Mechanical and Aerospace Engineering and School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 639798 (Singapore); School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 639798 (Singapore); School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

    2005-11-21T23:59:59.000Z

    We have demonstrated the functionalization of single-wall carbon nanotubes (SWNTs) by argon (Ar) plasma-assisted ultraviolet (UV) grafting of 1-vinylimidazole (VZ). The Ar plasma treatment generates defect sites at the tube ends and sidewalls, which act as the active sites for the subsequent UV grafting of VZ monomer. Atomic force microscopy analyses indicate that the original nanotube bundles exfoliate to individual tubes after the VZ grafting. By control of the deposited energy of Ar plasma treatment (200 W) and treatment time (5 min), no visible chopping of the functionalized SWNT was observed. This method may be extended to other vinyl monomers and offers another diverse way of sidewall functionalization of SWNT.

  12. The effects of concentrated ultraviolet light on high-efficiency silicon solar cells

    SciTech Connect (OSTI)

    Ruby, D.S.; Schubert, W.K.

    1991-01-01T23:59:59.000Z

    The importance of stability in the performance of solar cells is clearly recognized as fundamental. Some of the highest efficiency silicon solar cells demonstrated to date, such as the Point Contact solar cell and the Passivated Emitter solar cell, rely upon the passivation of cell surfaces in order to minimize recombination, which reduces cell power output. Recently, it has been shown that exposure to ultraviolet (UV) light of wavelengths present in the terrestrial solar spectrum can damage a passivating silicon-oxide interface and increase recombination. In this study, we compared the performance of Point Contact and Passivated Emitter solar cells after exposure to UV light. We also examined the effect of UV exposure on oxide-passivated silicon wafers. We found that current Passivated Emitter designs are stable at both one-sun and under concentrated sunlight. The evolution of Point Contact concentrator cell performance shows a clear trend towards more stable cells. 15 refs., 18 figs.

  13. Evaluation of Ultra-Violet Photocatalytic Oxidation for Indoor AirApplications

    SciTech Connect (OSTI)

    Hodgson, A.T.; Sullivan, D.P.; Fisk, W.J.

    2006-02-01T23:59:59.000Z

    Acceptable indoor air quality in office buildings may be achieved with less energy by combining effective air cleaning systems for volatile organic compounds (VOCs) with particle filtration then by relying solely on ventilation. For such applications, ultraviolet photocatalytic oxidation (UVPCO) systems are being developed for VOC destruction. An experimental evaluation of a UVPCO system is reported. The evaluation was unique in that it employed complex mixtures of VOCs commonly found in office buildings at realistically low concentrations. VOC conversion efficiencies varied over a broad range, usually exceeded 20%, and were as high as {approx}80%. Conversion efficiency generally diminished with increased air flow rate. Significant amounts of formaldehyde and acetaldehyde were produced due to incomplete mineralization. The results indicate that formaldehyde and acetaldehyde production rates may need to be reduced before such UVPCO systems can be deployed safely in occupied buildings.

  14. Electronic Excitations in B12As2 and their Temperature Dependence by Vacuum Ultraviolet Ellipsometry

    SciTech Connect (OSTI)

    S Bakalova; Y Gong; C Cobet; N Esser; Y Zhang; J Edgar; Y Zhang; M Dudley; M Kuball

    2011-12-31T23:59:59.000Z

    The dielectric response function of epitaxial B{sub 12}As{sub 2} films on 4H-SiC was determined at room temperature and at 10 K in the spectral region of 3.6-9.8 eV, i.e., in the vacuum ultraviolet (VUV) spectral region, by synchrotron ellipsometry. The experimental dielectric function was simulated with the critical point parabolic band model. The parameters of the dispersive structures were derived by numerical fitting of the experimental data to the proposed model. New high energy optical transitions are resolved at 5.95, 7.8 and 8.82 eV and their lineshape and origin are discussed. The temperature dependence of the critical point energies and transition strengths was determined, and the excitonic effect is considered.

  15. QUIET-SUN INTENSITY CONTRASTS IN THE NEAR-ULTRAVIOLET AS MEASURED FROM SUNRISE

    SciTech Connect (OSTI)

    Hirzberger, J.; Feller, A.; Riethmueller, T. L.; Schuessler, M.; Borrero, J. M.; Gandorfer, A.; Solanki, S. K.; Barthol, P. [Max-Planck-Institut fuer Sonnensystemforschung, D-37434 Katlenburg-Lindau (Germany); Afram, N.; Unruh, Y. C. [Astrophysics Group, Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom); Berdyugina, S. V.; Berkefeld, T.; Schmidt, W. [Kiepenheuer-Institut fuer Sonnenphysik, D-79104 Freiburg (Germany); Bonet, J. A.; MartInez Pillet, V. [Instituto de Astrofisica de Canarias, E-38200 La Laguna (Spain); Knoelker, M. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO 80307 (United States); Title, A. M., E-mail: hirzberger@mps.mpg.d [Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94305 (United States)

    2010-11-10T23:59:59.000Z

    We present high-resolution images of the Sun in the near-ultraviolet spectral range between 214 nm and 397 nm as obtained from the first science flight of the 1 m SUNRISE balloon-borne solar telescope. The quiet-Sun rms intensity contrasts found in this wavelength range are among the highest values ever obtained for quiet-Sun solar surface structures-up to 32.8% at a wavelength of 214 nm. We compare the rms contrasts obtained from the observational data with theoretical intensity contrasts obtained from numerical magnetohydrodynamic simulations. For 388 nm and 312 nm the observations agree well with the numerical simulations whereas at shorter wavelengths discrepancies between observed and simulated contrasts remain.

  16. Ultraviolet-B radiation enhancement in dielectric barrier discharge based xenon chloride exciplex source by air

    SciTech Connect (OSTI)

    Gulati, P., E-mail: pgulati1512@gmail.com [CSIR-Central Electronics Engineering Research Institute (CSIR-CEERI), Pilani, Rajasthan-333031 (India); Department of Physics, Banasthali University, P.O. Banasthali Vidyapith, Rajasthan 304022 (India); Prakash, R.; Pal, U. N.; Kumar, M. [CSIR-Central Electronics Engineering Research Institute (CSIR-CEERI), Pilani, Rajasthan-333031 (India); Vyas, V. [Department of Physics, Banasthali University, P.O. Banasthali Vidyapith, Rajasthan 304022 (India)

    2014-07-07T23:59:59.000Z

    A single barrier dielectric barrier discharge tube of quartz with multi-strip Titanium-Gold (Ti-Au) coatings have been developed and utilized for ultraviolet-B (UV-B) radiation production peaking at wavelength 308?nm. The observed radiation at this wavelength has been examined for the mixtures of the Xenon together with chlorine and air admixtures. The gas mixture composition, chlorine gas content, total gas pressure, and air pressure dependency of the UV intensity, has been analyzed. It is found that the larger concentration of Cl{sub 2} deteriorates the performance of the developed source and around 2% Cl{sub 2} in this source produced optimum results. Furthermore, an addition of air in the xenon and chlorine working gas environment leads to achieve same intensity of UV-B light but at lower working gas pressure where significant amount of gas is air.

  17. Reliable self-powered highly spectrum-selective ZnO ultraviolet photodetectors

    SciTech Connect (OSTI)

    Shen, H. [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China) [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Shan, C. X., E-mail: shancx@ciomp.ac.cn, E-mail: binghuili@163.com; Li, B. H., E-mail: shancx@ciomp.ac.cn, E-mail: binghuili@163.com; Shen, D. Z. [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)] [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China); Xuan, B. [Key Laboratory of Optical System Advanced Manufacturing Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)] [Key Laboratory of Optical System Advanced Manufacturing Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033 (China)

    2013-12-02T23:59:59.000Z

    Ultraviolet photodetectors (PDs) have been fabricated from p-ZnO:(Li,N)/n-ZnO structures in this Letter. The PDs can operate without any external power supply and show response only to a very narrow spectrum range. The self-power character of the devices is due to the built-in electric field in the p-n junctions that can separate the photogenerated electrons and holes while the high spectrum-selectivity has been attributed to the filter effect of the neutral region in the ZnO:(Li,N) layer. The performance of the self-powered highly spectrum-selective PDs degrades little after five months, indicating their good reliability.

  18. Ultraviolet stimulated electron source for use with low energy plasma instrument calibration

    E-Print Network [OSTI]

    Henderson, Kevin; Funsten, Herb; MacDonald, Elizabeth

    2011-01-01T23:59:59.000Z

    We report the development of a versatile, compact, low to medium energy electron source. A collimated, monoenergetic beam of electrons, up to 50 mm in diameter, is produced with energies ranging from 0.03 to 30 keV. A uniform electron beam profile is generated by illuminating a metal cathode plate with a near ultraviolet (UV) light emitting diode (LED). A parallel electric field accelerates the electrons away from the cathode plate towards a grounded grid. The beam intensity can be controlled from 10 - 10^9 electrons cm-2 s-1 and the angular divergence of the beam is less than 1 degree FWHM for energies greater than 1 keV.

  19. Tailoring plasmon resonances in the deep-ultraviolet by size-tunable fabrication of aluminum nanostructures

    SciTech Connect (OSTI)

    Taguchi, Atsushi [Nanophotonics Laboratory, RIKEN, Wako, Saitama 351-0198 (Japan); Saito, Yuika; Watanabe, Koichi; Yijian, Song [Department of Applied Physics, Osaka University, Suita, Osaka 565-0871 (Japan); Kawata, Satoshi [Nanophotonics Laboratory, RIKEN, Wako, Saitama 351-0198 (Japan); Department of Applied Physics, Osaka University, Suita, Osaka 565-0871 (Japan)

    2012-08-20T23:59:59.000Z

    Localized surface plasmon resonances were controlled at deep-ultraviolet (DUV) wavelengths by fabricating aluminum (Al) nanostructures in a size-controllable manner. Plasmon resonances were obtained at wavelengths from near-UV down to 270 nm (4.6 eV) depending on the fabricated structure size. Such precise size control was realized by the nanosphere lithography technique combined with additional microwave heating to shrink the spaces in a close-packed monolayer of colloidal nanosphere masks. By adjusting the microwave heating time, the sizes of the Al nanostructures could be controlled from 80 nm to 50 nm without the need to use nanosphere beads of different sizes. With the outstanding controllability and versatility of the presented fabrication technique, the fabricated Al nanostructure is promising for use as a DUV plasmonic substrate, a light-harvesting platform for mediating strong light-matter interactions between UV photons and molecules placed near the metal nanostructure.

  20. Tunable vacuum ultraviolet laser based spectrometer for angle resolved photoemission spectroscopy

    SciTech Connect (OSTI)

    Jiang, Rui; Mou, Daixiang; Wu, Yun; Huang, Lunan; Kaminski, Adam [Division of Materials Science and Engineering, Ames Laboratory, Ames, Iowa 50011 (United States) [Division of Materials Science and Engineering, Ames Laboratory, Ames, Iowa 50011 (United States); Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States); McMillen, Colin D.; Kolis, Joseph [Department of Chemistry, Clemson University, Clemson, South Carolina 29634 (United States)] [Department of Chemistry, Clemson University, Clemson, South Carolina 29634 (United States); Giesber, Henry G.; Egan, John J. [Advanced Photonic Crystals LLC, Fort Mill, South Carolina 29708 (United States)] [Advanced Photonic Crystals LLC, Fort Mill, South Carolina 29708 (United States)

    2014-03-15T23:59:59.000Z

    We have developed an angle-resolved photoemission spectrometer with tunable vacuum ultraviolet laser as a photon source. The photon source is based on the fourth harmonic generation of a near IR beam from a Ti:sapphire laser pumped by a CW green laser and tunable between 5.3 eV and 7 eV. The most important part of the set-up is a compact, vacuum enclosed fourth harmonic generator based on potassium beryllium fluoroborate crystals, grown hydrothermally in the US. This source can deliver a photon flux of over 10{sup 14} photon/s. We demonstrate that this energy range is sufficient to measure the k{sub z} dispersion in an iron arsenic high temperature superconductor, which was previously only possible at synchrotron facilities.

  1. Deep ultraviolet photoluminescence of Tm-doped AlGaN alloys

    SciTech Connect (OSTI)

    Nepal, N.; Zavada, J. M. [Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Lee, D. S.; Steckl, A. J. [Nanoelectronics Laboratory, University of Cincinnati, Cincinnati, Ohio 45221 (United States); Sedhain, A.; Lin, J. Y.; Jiang, H. X. [Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock, Texas 79409 (United States)

    2009-03-16T23:59:59.000Z

    The ultraviolet (UV) photoluminescence (PL) properties of Tm-doped Al{sub x}Ga{sub 1-x}N (0.39{<=}x{<=}1) alloys grown by solid-source molecular beam epitaxy were probed using above-bandgap excitation from a laser source at 197 nm. The PL spectra show dominant UV emissions at 298 and 358 nm only for samples with x=1 and 0.81. Temperature dependence of the PL intensities of these emission lines reveals exciton binding energies of 150 and 57 meV, respectively. The quenching of these UV emissions appears related to the thermal activation of the excitons bound to rare-earth structured isovalent (RESI) charge traps, which transfer excitonic energy to Tm{sup 3+} ions resulting in the UV emissions. A model of the RESI trap levels in AlGaN alloys is presented.

  2. Spectral dependencies of killing, mutation, and transformation in mammalian cells and their relevance to hazards caused by solar ultraviolet radiation

    SciTech Connect (OSTI)

    Suzuki, F.; Han, A.; Lankas, G.R.; Utsumi, H.; Elkind, M.M.

    1981-12-01T23:59:59.000Z

    Using germicidal lamps and Westinghouse sunlamps with and without filtration, the effectiveness of ultraviolet and near-ultraviolet light in inducing molecular and cellular changes was measured. Cell survival and the induction of resistance to 6-thioguanine or to ouabain were measured with V79 Chinese hamster cells, cell survival and neoplastic transformation were measured with C3H mouse 10 T 1/2 cells, and the induction of pyrimidine dimers containing thymine was measured in both cell lines. The short-wavelength cutoff of the sunlamp emission was shifted from approximately 290 nm (unfiltered) to approximately 300 and approximately 310 nm by appropriate filters. Although it was found that the efficiency with which all end points were induced progressively decreased as the short-wavelength cutoff was shifted to longer wavelengths, the rates of decrease differed appreciably. For example, doses of near-ultraviolet light longer than approximately 300 nm that were effective in mutating or in transforming cells were ineffective in killing them. In respect to pyrimidine dimer induction, several but not all cellular end points were induced by dose ratios of sunlamp light (short-wavelength cutoff, approximately 290 nm) to germicidal lamp light (254 nm) in fairly close accord with the doses required to produce equivalent proportions of dimers. However, for near-ultraviolet light having cutoffs at longer wavelengths, the biological action observed was appreciably greater than what would be predicted from the proportion of dimers induced. From the latter observation, it is inferred that increasing intensities of short-wavelength ultraviolet light, as would be expected from reductions in stratospheric ozone around the earth, would result in smaller increases in biological action, e.g., skin cancer, compared to current levels of action than would be predicted from an action spectrum completely corresponding to that of a pyrimidine dimer induction spectrum in DNA.

  3. Far-ultraviolet observations of comet C/2001 Q4 (NEAT) with FIMS/SPEAR

    SciTech Connect (OSTI)

    Lim, Y.-M.; Min, K.-W. [Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Feldman, P. D. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Han, W. [Korea Astronomy and Space Science Institute (KASI), 776 Daedeokdae-ro, Yuseong-gu, Daejeon 305-348 (Korea, Republic of); Edelstein, J., E-mail: ymlim@kaist.ac.kr [Space Sciences Laboratory, University of California, Berkeley, 7 Gauss Way, Berkeley, CA 94720 (United States)

    2014-02-01T23:59:59.000Z

    We present the results of far-ultraviolet observations of comet C/2001 Q4 (NEAT) that were made with the Far-Ultraviolet Imaging Spectrograph on board the Korean satellite STSAT-1. The observations were conducted in two campaigns during its perihelion approach between 2004 May 8 and 15. Based on the scanning mode observations in the wavelength band of 1400-1700 Å, we have constructed an image of the comet with an angular size of 5°×5°, which corresponds to the central coma region. Several important fluorescence emission lines were detected including S I multiplets at 1429 and 1479 Å, C I multiplets at 1561 and 1657 Å, and the CO A{sup 1}?-X{sup 1}?{sup +} Fourth Positive system; we have estimated the production rates of the corresponding species from the fluxes of these emission lines. The estimated production rate of CO was Q {sub CO} = (2.65 ± 0.63) × 10{sup 28} s{sup –1}, which is 6.2%-7.4% of the water production rate and is consistent with earlier predictions. The average carbon production rate was estimated to be Q{sub C} = ?1.59 × 10{sup 28} s{sup –1}, which is ?60% of the CO production rate. However, the observed carbon profile was steeper than that predicted using the two-component Haser model in the inner coma region, while it was consistent with the model in the outer region. The average sulfur production rate was Q{sub S} = (4.03±1.03) × 10{sup 27} s{sup –1}, which corresponds to ?1% of the water production rate.

  4. Director, Division of Investigations

    Broader source: Energy.gov [DOE]

    The Federal Energy Regulatory Commission is looking for an experienced, highly skilled executive to serve as Director of the Division of Investigations (DOI) in the Office of Enforcement (OE). The...

  5. Best Practices in Literature Review for the 10 Year Extreme Wind...

    Office of Environmental Management (EM)

    at the DOE Pantex Site More Documents & Publications SUMMARY OF REVISED TORNADO, HURRICANE AND EXTREME STRAIGHT WIND CHARACTERISTICS AT NUCLEAR FACILITY SITES Natural...

  6. Extreme Compass and Dynamic Multi-Armed Bandits for Adaptive Operator Selection

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Extreme Compass and Dynamic Multi-Armed Bandits for Adaptive Operator Selection Jorge Maturana developed Adaptive Operator Selection methods are combined here: Compass evaluates the performance

  7. Northeast Climate Science Center: Transposing Extreme Rainfall to Assess Climate Vulnerability

    Office of Energy Efficiency and Renewable Energy (EERE)

    Climate models predict significant increases in the magnitude and frequency of extreme rainfalls.  However, climate model projections of precipitation vary greatly across models.  For communities...

  8. Investigations | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed off Energy.gov. Are you sure you want toworldPowerHome|InformationInvestigations Investigations

  9. Extreme point inequalities and geometry of the rank sparsity ball

    E-Print Network [OSTI]

    D. Drusvyatskiy

    2014-01-19T23:59:59.000Z

    Jan 19, 2014 ... Abstract: We investigate geometric features of the unit ball corresponding to the sum of the nuclear norm of a matrix and the l_1 norm of its ...

  10. Quantum-Based Atomistic Simulation of Metals at Extreme Conditions

    SciTech Connect (OSTI)

    Moriarty, J A; Glosli, J N; Hood, R Q; Klepeis, J E; Orlikowski, D A; Soderlind, P; Yang, L H

    2008-01-15T23:59:59.000Z

    First-principles generalized pseudopotential theory (GPT) provides a fundamental basis for bridging the quantum-atomistic gap from density-functional quantum mechanics to large scale atomistic simulation in metals and alloys. In directionally-bonded bcc transition metals, advanced generation model GPT or MGPT potentials based on canonical d bands have been developed for Ta, Mo and V and successfully applied to a wide range of thermodynamic and mechanical properties at both ambient and extreme conditions of pressure and temperature, including high-pressure phase transitions, multiphase equation of state; melting and solidification; thermoelasticity; and the atomistic simulation of point defects, dislocations and grain boundaries needed for the multiscale modeling of plasticity and strength. Recent algorithm improvements have also allowed an MGPT implementation beyond canonical bands to achieve increased accuracy, extension to f-electron actinide metals, and high computational speed. A further advance in progress is the development temperature-dependent MGPT potentials that subsume electron-thermal contributions to high-temperature properties.

  11. Extreme bendability of DNA double helix due to bending asymmetry

    E-Print Network [OSTI]

    Salari, Hossein; Naderi, M S; Ejtehadi, M R

    2015-01-01T23:59:59.000Z

    Experimental data of the DNA cyclization (J-factor) at short length scales, as a way to study the elastic behavior of tightly bent DNA, exceed the theoretical expectation based on the wormlike chain (WLC) model by several orders of magnitude. Here, we propose that asymmetric bending rigidity of the double helix in the groove direction can be responsible for extreme bendability of DNA at short length scales and it also facilitates DNA loop formation at these lengths. To account for the bending asymmetry, we consider the asymmetric elastic rod (AER) model which has been introduced and parametrized in an earlier study (B. Eslami-Mossallam and M. Ejtehadi, Phys. Rev. E 80, 011919 (2009)). Exploiting a coarse grained representation of DNA molecule at base pair (bp) level, and using the Monte Carlo simulation method in combination with the umbrella sampling technique, we calculate the loop formation probability of DNA in the AER model. We show that, for DNA molecule has a larger J-factor compared to the WLC model w...

  12. 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. [Particle Physics Division, Fermilab, P.O. Box 500, Batavia, IL 60510 (United States)

    2014-01-29T23:59:59.000Z

    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.

  13. BAL QSOs and Extreme UFOs: the Eddington connection

    E-Print Network [OSTI]

    Zubovas, Kastytis

    2013-01-01T23:59:59.000Z

    We suggest a common physical origin connecting the fast, highly ionized winds (UFOs) seen in nearby AGN, and the slower and less ionized winds of BAL QSOs. The primary difference is the mass loss rate in the wind, which is ultimately determined by the rate at which mass is fed towards the central supermassive black hole (SMBH) on large scales. This is below the Eddington accretion rate in most UFOs, and slightly super-Eddington in extreme UFOs such as PG1211+143, but ranges up to $\\sim 10-50$ times this in BAL QSOs. For UFOs this implies black hole accretion rates and wind mass loss rates which are at most comparable to Eddington, giving fast, highly-ionized winds. In contrast BAL QSO black holes have mildly super-Eddington accretion rates, and drive winds whose mass loss rates are significantly super-Eddington, and so are slower and less ionized. This picture correctly predicts the velocities and ionization states of the observed winds, including the recently-discovered one in SDSS J1106+1939. We suggest tha...

  14. Effect of ultraviolet radiation exposure on room-temperature hydrogen sensitivity of nanocrystalline doped tin oxide sensor incorporated into microelectromechanical systems device

    SciTech Connect (OSTI)

    Shukla, Satyajit; Agrawal, Rajnikant; Cho, Hyoung J.; Seal, Sudipta; Ludwig, Lawrence; Parish, Clyde [Advanced Materials Processing and Analysis Center (AMPAC) and Mechanical Materials Aerospace Engineering (MMAE) Department, Engineering 381, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816 (United States); National Aeronautics and Space Administration (NASA), John F. Kennedy Space Center, Kennedy Space Center (KSC), Florida 32899 (United States)

    2005-03-01T23:59:59.000Z

    The effect of ultraviolet (UV) radiation exposure on the room-temperature hydrogen (H{sub 2}) sensitivity of nanocrystalline indium oxide (In{sub 2}O{sub 3})-doped tin oxide (SnO{sub 2}) thin-film gas sensor is investigated in this article. The present sensor is incorporated into microelectromechanical systems device using sol-gel dip-coating technique. The present sensor exhibits a very high sensitivity, as high as 65 000-110 000, at room temperature, for 900 ppm of H{sub 2} under the dynamic test condition without UV exposure. The H{sub 2} sensitivity is, however, observed to reduce to 200 under UV radiation, which is contrary to the literature data, where an enhanced room-temperature gas sensitivity has been reported under UV radiation. The observed phenomenon is attributed to the reduced surface coverage by the chemisorbed oxygen ions under UV radiation, which is in consonance with the prediction of the constitutive equation, proposed recently by the authors, for the gas sensitivity of nanocrystalline semiconductor oxide thin-film sensors.

  15. Temperature-dependent Raman and ultraviolet photoelectron spectroscopy studies on phase transition behavior of VO{sub 2} films with M1 and M2 phases

    SciTech Connect (OSTI)

    Okimura, Kunio, E-mail: okifn@keyaki.cc.u-tokai.ac.jp; Hanis Azhan, Nurul [Graduate School of Engineering, Tokai University, Hiratsuka 259-1292 (Japan); Hajiri, Tetsuya [UVSOR Facility, Institute for Molecular Science, Okazaki 444-8585 (Japan); Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Kimura, Shin-ichi [UVSOR Facility, Institute for Molecular Science, Okazaki 444-8585 (Japan); Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871 (Japan); Zaghrioui, Mustapha; Sakai, Joe [GREMAN, UMR 7347 CNRS, Université François Rabelais de Tours, Parc de Grandmont, 37200 Tours (France)

    2014-04-21T23:59:59.000Z

    Structural and electronic phase transitions behavior of two polycrystalline VO{sub 2} films, one with pure M1 phase and the other with pure M2 phase at room temperature, were investigated by temperature-controlled Raman spectroscopy and ultraviolet photoelectron spectroscopy (UPS). We observed characteristic transient dynamics in which the Raman modes at 195?cm{sup ?1} (V-V vibration) and 616?cm{sup ?1} (V-O vibration) showed remarkable hardening along the temperature in M1 phase film, indicating the rearrangements of V-V pairs and VO{sub 6} octahedra. It was also shown that the M1 Raman mode frequency approached those of invariant M2 peaks before entering rutile phase. In UPS spectra with high energy resolution of 0.03?eV for the M2 phase film, narrower V{sub 3d} band was observed together with smaller gap compared to those of M1 phase film, supporting the nature of Mott insulator of M2 phase even in the polycrystalline film. Cooperative behavior of lattice rearrangements and electronic phase transition was suggested for M1 phase film.

  16. September 2009 INVESTIGATORS

    E-Print Network [OSTI]

    Varela, Carlos

    September 2009 SPONSORED PROJECTS GUIDE FOR PRINICIPAL INVESTIGATORS Cost Transfers Cost transfers to a project cannot be transferred to that project, even temporarily. Instead, use an Institute discretionary" or "to transfer to correct project" is not sufficient. Transfers of costs from one project to another

  17. Ultraviolet emission from a multi-layer graphene/MgZnO/ZnO light-emitting diode

    SciTech Connect (OSTI)

    Kang, Jang-Won; Choi, Yong-Seok; Goo Kang, Chang; Hun Lee, Byoung [School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Kim, Byeong-Hyeok [Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Tu, C. W. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093-0407 (United States); Park, Seong-Ju, E-mail: sjpark@gist.ac.kr [School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

    2014-02-03T23:59:59.000Z

    We report on ultraviolet emission from a multi-layer graphene (MLG)/MgZnO/ZnO light-emitting diodes (LED). The p-type MLG and MgZnO in the MLG/MgZnO/ZnO LED are used as transparent hole injection and electron blocking layers, respectively. The current-voltage characteristics of the MLG/MgZnO/ZnO LED show that current transport is dominated by tunneling processes in the MgZnO barrier layer under forward bias conditions. The holes injected from p-type MLG recombine efficiently with the electrons accumulated in ZnO, and the MLG/MgZnO/ZnO LED shows strong ultraviolet emission from the band edge of ZnO and weak red-orange emission from the deep levels of ZnO.

  18. A passive measurement of dissociated atom densities in atmospheric pressure air discharge plasmas using vacuum ultraviolet self-absorption spectroscopy

    SciTech Connect (OSTI)

    Laity, George [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Applied Science and Technology Maturation Department, Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States); Fierro, Andrew; Dickens, James; Neuber, Andreas [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Frank, Klaus [Erlangen Centre for Astroparticle Physics, Department of Physics, Friedrich–Alexander University at Erlangen-Nürnberg, 91058 Erlangen (Germany)

    2014-03-28T23:59:59.000Z

    We demonstrate a method for determining the dissociation degree of atmospheric pressure air discharges by measuring the self-absorption characteristics of vacuum ultraviolet radiation from O and N atoms in the plasma. The atom densities are determined by modeling the amount of radiation trapping present in the discharge, without the use of typical optical absorption diagnostic techniques which require external sources of probing radiation into the experiment. For an 8.0?mm spark discharge between needle electrodes at atmospheric pressure, typical peak O atom densities of 8.5?×?10{sup 17}?cm{sup ?3} and peak N atom densities of 9.9?×?10{sup 17}?cm{sup ?3} are observed within the first ?1.0?mm of plasma near the anode tip by analyzing the OI and NI transitions in the 130.0–132.0?nm band of the vacuum ultraviolet spectrum.

  19. Mining Extremes: Severe Rainfall and Climate Change Debasish Das1,2,*

    E-Print Network [OSTI]

    Obradovic, Zoran

    Mining Extremes: Severe Rainfall and Climate Change Debasish Das1,2,* and Evan Kodra2 and Zoran ranging from climate change and critical infrastructures to insurance and financial markets. Here we mining and AI. The growing importance of extremes, for example in the context of climate change

  20. Mining Extreme Values: Climate and Natural Hazards Debasish Das1,2

    E-Print Network [OSTI]

    Obradovic, Zoran

    extremes time-series. Besides providing insights on climate change or natural hazards and the consequences for climate change science or the re- insurance industry, the methods can be generalized to multiple domains, cyber- security and mapping technologies. Keywords Precipitation, Climate Change, Extremes Regression

  1. Interannual Rainfall Extremes over Southwest Western Australia Linked to Indian Ocean Climate Variability

    E-Print Network [OSTI]

    Ummenhofer, Caroline C.

    Interannual Rainfall Extremes over Southwest Western Australia Linked to Indian Ocean Climate and Prediction, School of Mathematics, University of New South Wales, Sydney, Australia (Manuscript received 15 December 2004, in final form 24 August 2005) ABSTRACT Interannual rainfall extremes over southwest Western

  2. Extreme type-II superconductors in a magnetic field: A theory of critical fluctuations Zlatko Tesanovic*

    E-Print Network [OSTI]

    Tesanovic, Zlatko

    Extreme type-II superconductors in a magnetic field: A theory of critical fluctuations Zlatko Received 4 February 1998 A theory of critical fluctuations in extreme type-II superconductors subjected-Landau representation of this problem can be recast, with help of a mapping, as a theory of a new ``superconductor

  3. LFTI: A New Performance Metric for Assessing Interconnect Designs for Extreme-Scale HPC Systems

    E-Print Network [OSTI]

    Pakin, Scott

    , New Mexico Email: {mlang,pakin}@lanl.gov Abstract--Traditionally, interconnect performance is eitherLFTI: A New Performance Metric for Assessing Interconnect Designs for Extreme-Scale HPC Systems Xin a good performance overview for extreme-scale interconnects. The topological pa- rameters

  4. Extreme Genomics By Scouring the Genomes of 50 HIV-Resistant People, Study

    E-Print Network [OSTI]

    Dolbow, John

    Extreme Genomics By Scouring the Genomes of 50 HIV-Resistant People, Study Takes Aim at Rare Gene Genome Variation, and his colleagues think that the complete genome sequences of those fortunate few against the viral strain that usually infects humans. That's because the CCR5 protein is Extreme Genomics

  5. Limit theory for the sample autocorrelations and extremes of a GARCH(1,1) Thomas Mikosch

    E-Print Network [OSTI]

    Mikosch, Thomas

    Limit theory for the sample autocorrelations and extremes of a GARCH(1,1) process Thomas Mikosch theory for the sample autocorrelations and extremes of a GARCH(1; 1) process is provided. Special attention is given to the case when the sum of the ARCH and GARCH parameters is close to one, i.e. when one

  6. Limit theory for the sample autocorrelations and extremes of a GARCH(1,1) Thomas Mikosch

    E-Print Network [OSTI]

    Mikosch, Thomas

    Limit theory for the sample autocorrelations and extremes of a GARCH(1,1) process Thomas Mikosch for the sample autocorrelations and extremes of a GARCH(1;1) process is provided. Special attention is given to the case when the sum of the ARCH and GARCH parameters is close to one, i.e. when one is close

  7. Extreme winds and the connection to reanalysis data Xiaoli Guo Larsn

    E-Print Network [OSTI]

    Extreme winds and the connection to reanalysis data Xiaoli Guo Larsén Jakob Mann and Hans Jørgensen Wind Energy Department, Risø National Laboratory 4000 Roskilde, Denmark Abstract We take first steps in constructing a worldwide extreme wind atlas with the NCEP/NCAR reanalysis data. In wind engineering, the key

  8. Increasing Climate Extremes and the New Climate Dice 10 August 2012

    E-Print Network [OSTI]

    Hansen, James E.

    1 Increasing Climate Extremes and the New Climate Dice 10 August 2012 James Hansen, Makiko Sato, and Reto Ruedy Abstract. We address questions raised about our study "The New Climate Dice" by using longer of weather extremes depends on many factors and to a large degree is a matter of chance. Changing climate can

  9. Extreme organic carbon burial fuels intense methane bubbling in a temperate reservoir

    E-Print Network [OSTI]

    Wehrli, Bernhard

    Extreme organic carbon burial fuels intense methane bubbling in a temperate reservoir Sebastian. Wehrli (2012), Extreme organic carbon burial fuels intense methane bubbling in a temperate reservoir; revised 25 November 2011; accepted 30 November 2011; published 4 January 2012. [1] Organic carbon (OC

  10. Extreme Security Engineering: On Employing XP Practices to Achieve "Good Enough Security"

    E-Print Network [OSTI]

    Extreme Security Engineering: On Employing XP Practices to Achieve "Good Enough Security" without Main Mall, Vancouver, BC Canada V6T 1Z4 beznosov@ece.ubc.ca ABSTRACT This paper examines practices of eXtreme Security Engineering (XSE), an application of XP practices to security engineering, and discuss its

  11. Kinematics of extreme waves in deep water John Grue*, Didier Clamond, Morten Huseby, Atle Jensen

    E-Print Network [OSTI]

    Clamond, Didier

    Kinematics of extreme waves in deep water John Grue*, Didier Clamond, Morten Huseby, Atle Jensen in the mean water level. q 2004 Elsevier Ltd. All rights reserved. Keywords: Wave kinematics; Extreme waves; PIV 1. Introduction Enhanced evidence and description of the kinematics during steep wave events

  12. EXTREME VALUE ANALYSIS FOR CLIMATE TIME SERIES Institute for Mathematics Applied to Geosciences

    E-Print Network [OSTI]

    Katz, Richard

    Approach (Extremes + Non-Extremes) (8) Risk Communication under Climate Change #12;4 (1) Background · Use.isse.ucar.edu/staff/katz/ Lecture: ···/staff/katz/docs/pdf/banffrwk.pdf #12;2 Quote "Climate change undermines a basic assumption Cycles (annual, diurnal) Trends (global climate change) Physically-based covariates (e. g., El Niño

  13. Equatorial currents transport changes for extreme warm and cold events in the Atlantic Ocean

    E-Print Network [OSTI]

    Equatorial currents transport changes for extreme warm and cold events in the Atlantic Ocean Marlos compositedevents.For the cold(warm)eventthe EUC shows a greater (reduced) transport and core velocity, and a deeper.Wainer, Equatorial currents transport changes for extreme warm and cold events in the Atlantic Ocean, Geophys. Res

  14. The effective spectral irradiance of ultra-violet radiations from inert-gas-shielded welding processes in relation to the ARC current density

    E-Print Network [OSTI]

    DeVore, Robin Kent

    1973-01-01T23:59:59.000Z

    THE EFFECTIVE SPECTRAL IRRADIANCE OF ULTRAVIOLET RADIATIONS FROM INERT-GAS-SHIELDED MELDING PROCESSES IN RELATION TO THE ARC CURRENT DENSITY A Thesis by ROBIN KENT DEVORE Submitted to the Graduate College of Texas A&M University in partial... fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1973 Major Subject: Industrial Hygiene THE EFFECTIVE SPECTRAL IRRADIANCE OF ULTRAVIOLET RADIATIONS FROM INERT-GAS-SHIELDED WELDING PROCESSES IN RELATION TO THE ARC CURRENT...

  15. The effective spectral irradiance of ultra-violet radiations from inert-gas-shielded welding processes in relation to the ARC current density 

    E-Print Network [OSTI]

    DeVore, Robin Kent

    1973-01-01T23:59:59.000Z

    fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1973 Major Subject: Industrial Hygiene THE EFFECTIVE SPECTRAL IRRADIANCE OF ULTRAVIOLET RADIATIONS FROM INERT-GAS-SHIELDED WELDING PROCESSES IN RELATION TO THE ARC CURRENT... DENSITY A Thesis by ROBIN KENT DEVORE Approved as to style and content by: C alarm n of o itte Hea o partment e er Member December 1973 ABSTRACT The Effective Spectral Irradiance of Ultraviolet Radiations from Inert-Gas-Shielded Welding...

  16. Entanglement and local extremes at an infinite-order quantum phase transition

    SciTech Connect (OSTI)

    Rulli, C. C.; Sarandy, M. S. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, 24210-346, Niteroi, RJ (Brazil)

    2010-03-15T23:59:59.000Z

    The characterization of an infinite-order quantum phase transition (QPT) by entanglement measures is analyzed. To this aim, we consider two closely related solvable spin-1/2 chains, namely, the Ashkin-Teller and the staggered XXZ models. These systems display a distinct pattern of eigenstates but exhibit the same thermodynamics, that is, the same energy spectrum. By performing exact diagonalization, we investigate the behavior of pairwise and block entanglement in the ground state of both models. In contrast with the XXZ chain, we show that pairwise entanglement fails in the characterization of the infinite-order QPT in the Ashkin-Teller model, although it can be achieved by analyzing the distance of the pair state from the separability boundary. Concerning block entanglement, we show that both XXZ and Ashkin-Teller models exhibit identical von Neumann entropies as long as a suitable choice of blocks is performed. Entanglement entropy is then shown to be able to identify the quantum phase diagram, even though its local extremes (either maximum or minimum) may also appear in the absence of any infinite-order QPT.

  17. Extremely correlated Fermi liquids in the limit of infinite dimensions

    SciTech Connect (OSTI)

    Perepelitsky, Edward, E-mail: eperepel@ucsc.edu; Sriram Shastry, B.

    2013-11-15T23:59:59.000Z

    We study the infinite spatial dimensionality limit (d??) of the recently developed Extremely Correlated Fermi Liquid (ECFL) theory (Shastry 2011, 2013) [17,18] for the t–J model at J=0. We directly analyze the Schwinger equations of motion for the Gutzwiller projected (i.e. U=?) electron Green’s function G. From simplifications arising in this limit d??, we are able to make several exact statements about the theory. The ECFL Green’s function is shown to have a momentum independent Dyson (Mori) self energy. For practical calculations we introduce a partial projection parameter ?, and obtain the complete set of ECFL integral equations to O(?{sup 2}). In a related publication (Zitko et al. 2013) [23], these equations are compared in detail with the dynamical mean field theory for the large U Hubbard model. Paralleling the well known mapping for the Hubbard model, we find that the infinite dimensional t–J model (with J=0) can be mapped to the infinite-U Anderson impurity model with a self-consistently determined set of parameters. This mapping extends individually to the auxiliary Green’s function g and the caparison factor ?. Additionally, the optical conductivity is shown to be obtainable from G with negligibly small vertex corrections. These results are shown to hold to each order in ?. -- Highlights: •Infinite-dimensional t–J model (J=0) studied within new ECFL theory. •Mapping to the infinite U Anderson model with self consistent hybridization. •Single particle Green’s function determined by two local self energies. •Partial projection through control variable ?. •Expansion carried out to O(?{sup 2}) explicitly.

  18. Effects of Mg-doped AlN/AlGaN superlattices on properties of p-GaN contact layer and performance of deep ultraviolet light emitting diodes

    SciTech Connect (OSTI)

    Al tahtamouni, T. M., E-mail: talal@yu.edu.jo [Department of Physics, Yarmouk University, Irbid 21163 (Jordan); Lin, J. Y.; Jiang, H. X. [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)] [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)

    2014-04-15T23:59:59.000Z

    Mg-doped AlN/AlGaN superlattice (Mg-SL) and Mg-doped AlGaN epilayers have been investigated in the 284 nm deep ultraviolet (DUV) light emitting diodes (LEDs) as electron blocking layers. It was found that the use of Mg-SL improved the material quality of the p-GaN contact layer, as evidenced in the decreased density of surface pits and improved surface morphology and crystalline quality. The performance of the DUV LEDs fabricated using Mg-SL was significantly improved, as manifested by enhanced light intensity and output power, and reduced turn-on voltage. The improved performance is attributed to the enhanced blocking of electron overflow, and enhanced hole injection.

  19. Noncommutative geometry in quantum field theory and the cosmogenic neutrino physics at the extreme energies

    E-Print Network [OSTI]

    Josip Trampetic

    2013-02-04T23:59:59.000Z

    Analysis of the covariant theta-exact noncommutative (NC) gauge field theory (GFT), inspired by high energy cosmic rays experiments, is performed in the framework of the inelastic neutrino-nucleon scatterings. Next we have have found neutrino two-point function and shows a closed form decoupled from the hard ultraviolet (UV) divergent term, from softened ultraviolet/infrared (UV/IR) mixing term, and from the finite terms as well. For a certain choice of the noncommutative parameter theta which preserves unitarity, problematic UV divergent and UV/IR mixing terms vanish. Non-perturbative modifications of the neutrino dispersion relations are assymptotically independent of the scale of noncommutativity in both, the low and high energy limits and may allow superluminal propagation.

  20. RESEARCH PROTOCOL SAFETY SURVEY PRINCIPAL INVESTIGATOR (PI)

    E-Print Network [OSTI]

    Karsai, Istvan

    NO e. Controlled Substances YES NO f. Ionizing Radiation: (1) Radioactive materials YES NO (2) Radiation generating equipment YES NO g. Nonionizing Radiation: (1) Ultraviolet Light YES NO (2) Lasers (class 3b or class 4) YES NO (3) Radiofrequency or microwave sources YES NO If the answer to any