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Multi-Megajoule NIF: Ushering In a New Era in High Energy Density Science

Description: This paper describes the status of the stadium-sized National Ignition Facility (NIF), the world's largest laser system and first operational multi-megajoule laser. The 192-beam NIF, located at Lawrence Livermore National Laboratory (LLNL), is 96% complete and scheduled for completion in March 2009. The NIF laser will produce nanosecond laser pulses with energies up to approximately 4 MJ in the infrared (laser wavelength = 1.053-{micro}m) and 2MJ in the ultraviolet (laser wavelength = 0.35-{mic… more
Date: April 30, 2008
Creator: Keane, C & Moses, E I
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electric-dipole 5s - 5p Transitions in Promethiumlike Ions

Description: The 5s-5p electric-dipole resonance transitions in highly ionized promethiumlike ions have been studied applying relativistic multi-reference Moeller-Plesset second-order perturbation theory. The transition wavelengths are determined to within 0.2 {angstrom} in the more highly charged ions, where the level degeneracies are small. For somewhat lighter ions a very large reference space was used in order to account for the many degeneracies. In order to calculate transition probabilities and lifet… more
Date: February 29, 2008
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
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Partner: UNT Libraries Government Documents Department
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Measurements and Modeling of Coherent Synchrotron Radiation and its Impact on the LCLS Electron Beam

Description: In order to reach the high peak current required for an x-ray free electron laser, two separate magnetic dipole chicanes are used in the Linac Coherent Light Source (LCLS) accelerator to compress the electron bunch length in stages. In these bunch compressors, coherent synchrotron radiation (CSR) can be emitted either by a short electron bunch or by any longitudinal density modulation that may be on the bunch. In this paper, we report detailed measurements of the CSR-induced energy loss and tra… more
Date: December 18, 2008
Creator: Bane, K. L. F.; Decker, F. J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J. et al.
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Partner: UNT Libraries Government Documents Department
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Isothermal Martensitic and Pressure-Induced Delta to Alpha-Prime Phase Transformations in a Pu-Ga Alloy

Description: A well-homogenized Pu-2 at.% Ga alloy can be retained in the metastable face-centered cubic {delta} phase at room temperature. Ultimately, this metastable {delta} phase will decompose via a eutectoid transformation to the thermodynamically stable monoclinic {alpha} phase and the intermetallic compound Pu{sub 3}Ga over a period of approximately 10,000 years [1]. In addition, these low solute-containing {delta}-phase Pu alloys are metastable with respect to an isothermal martensitic phase transfo… more
Date: January 18, 2008
Creator: Schwartz, A J; Wall, M A; Farber, D L; Moore, K T & Blobaum, K M
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Partner: UNT Libraries Government Documents Department
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Single shot extreme ultraviolet laser imaging of nanostructures with wavelength resolution

Description: We have demonstrated near-wavelength resolution microscopy in the extreme ultraviolet. Images of 50 nm diameter nanotubes were obtained with a single {approx}1 ns duration pulse from a desk-top size 46.9 nm laser. We measured the modulation transfer function of the microscope for three different numerical aperture zone plate objectives, demonstrating that 54 nm half-period structures can be resolved. The combination of near-wavelength spatial resolution and high temporal resolution opens myriad… more
Date: January 7, 2008
Creator: Jones, Juanita; Brewer, Courtney A.; Brizuela, Fernando; Wachulak, Przemyslaw; Martz, Dale H.; Chao, Weilun et al.
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Partner: UNT Libraries Government Documents Department
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LINAC DESIGN FOR AN ARRAY OF SOFT X-RAY FREE ELECTRON LASERS

Description: The design of the linac delivering electron bunches into ten independent soft x-ray free electron lasers (FELs) producing light at 1 nm and longer wavelengths is presented. The bunch repetition rate in the linac is 1 MHz and 100 kHz in each of ten FEL beam lines. Various issues regarding machine layout and lattice, bunch compression, collimation, and the beam switch yard are discussed. Particular attention is given to collective effects. A demanding goal is to preserve both a low beam slice emi… more
Date: September 22, 2008
Creator: Zholents, Alexander A.; Kur, E.; Penn, G.; Qiang, Ji; Venturini, M. & Wells, R. P.
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Partner: UNT Libraries Government Documents Department
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Energy loss of coasting gold ions and deuterons in RHIC.

Description: The total energy loss of coasting gold ion beams was measured at RHIC at two energies, corresponding to a gamma of 75.2 and 107.4. We describe the experiment and observations and compare the measured total energy loss with expectations from ionization losses at the residual gas, the energy loss due to impedance and synchrotron radiation. We find that the measured energy losses are below what is expected from free space synchrotron radiation. We believe that this shows evidence for suppression o… more
Date: June 23, 2008
Creator: Abreu,N.; Blaskiewicz, M.; Brown, K.A.; Butler, J.J.; FischW; Harvey, M. et al.
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Partner: UNT Libraries Government Documents Department
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EUV mask reflectivity measurements with micron-scale spatial resolution

Description: The effort to produce defect-free mask blanks for EUV lithography relies on increasing the detection sensitivity of advanced mask inspection tools, operating at several wavelengths. We describe the unique measurement capabilities of a prototype actinic (EUV wavelength) microscope that is capable of detecting small defects and reflectivity changes that occur on the scale of microns to nanometers. Types of defects: (a) Buried Substrate Defects: particles & pits (causes amplitude and/or phase vari… more
Date: May 26, 2008
Creator: Goldberg, Kenneth A.; Rekawa, S. B.; Kemp, C. D.; Barty, A.; Anderson, E. H.; Kearney, Patrick et al.
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Partner: UNT Libraries Government Documents Department
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Spatial resolution limits for synchrotron-based spectromicroscopy in the mid- and near-infrared

Description: Spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source in Berkeley, CA, USA, a third-generation synchrotron light source. This beamline couples the high-brightness synchrotron source to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests were performed in both the mid-IR and near-IR. The results are compared with a diffraction-limited spot size theory. At shorter near-IR wavelengths the experimental results begin to deviate from dif… more
Date: January 12, 2008
Creator: Levenson, Erika; Lerch, Philippe & Martin, Michael C.
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Partner: UNT Libraries Government Documents Department
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Slow Waves in Fractures Filled with Viscous Fluid

Description: Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type so… more
Date: January 8, 2008
Creator: Korneev, Valeri
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Partner: UNT Libraries Government Documents Department
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Fast six-channel pyrometer for warm-dense-matter experiments with intense heavy-ion beams

Description: This paper describes a fast multi-channel radiation pyrometer that was developed for warmdense-matter experiments with intense heavy ion beams at Gesellschaft fur Schwerionenforschung mbH (GSI). The pyrometer is capable of measuring of brightness temperatures from 2000 K to 50000 K, at 6 wavelengths in visible and near-infrared parts of spectrum, with 5 nanosecond temporal resolution and several micrometers spatial resolution. The pyrometer's spectral discrimination technique is based on interf… more
Date: December 1, 2008
Creator: Ni, P.A.; Kulish, M.I.; Mintsev, V.; Nikolaev, D.N.; Ternovoi, V.Ya.; Hoffmann, D.H.H. et al.
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Partner: UNT Libraries Government Documents Department
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IR Spectrometer Using 90-Degree Off-Axis Parabolic Mirrors

Description: A gated spectrometer has been designed for real-time, pulsed infrared (IR) studies at the National Synchrotron Light Source at the Brookhaven National Laboratory. A pair of 90-degree, off-axis parabolic mirrors are used to relay the light from an entrance slit to an output recording camera. With an initial wavelength range of 1500–4500 nm required, gratings could not be used in the spectrometer because grating orders would overlap. A magnesium oxide prism, placed between these parabolic mirrors… more
Date: March 1, 2008
Creator: Malone, Robert M. & McKenna, Ian J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mask inspection microscopy with 13.2 nm table-top laser illumination

Description: We report the demonstration of a reflection microscope that operates at 13.2-nm wavelength with a spatial resolution of 55 {+-} 3 nm. The microscope uses illumination from a table-top EUV laser to acquire aerial images of photolithography masks with a 20 second exposure time. The modulation transfer function of the optical system was characterized.
Date: October 14, 2008
Creator: Brizuela, Fernando; Wang, Yong; Brewer, Courtney A.; Pedaci, Francesco; Chao, Weilun; Anderson, Erik H. et al.
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Partner: UNT Libraries Government Documents Department
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Modified Visible and Infrared Optical Design for the ITER Upper Ports

Description: This document reports the results of a follow-on optical design study of visible-light and infrared optics for the ITER upper ports, performed by LLNL under contract for the US ITER Project Office. The major objectives of this work are to move the viewing aperture closer to the plasma so that the optical path does not cut through any adjacent blanket shield module other than the module designated for the port; move optics forward into the port tube to increase the aperture size and therefore im… more
Date: April 24, 2008
Creator: Lasnier, C; Seppala, L & Morris, K
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Progress in Large Period Multilayer Coatings for High Harmonic and Solar Applications

Description: Multilayer coatings for normal incidence optics designed for the long wavelength region (25 nm < {lambda} < 50 nm) are particularly challenging due to the few number of layers that can be utilized in the reflection. Recently, Mg/SiC multilayers have been fabricated with normal incidence reflectivity in the vicinity of 40% for wavelengths near the He-II line at 30.4 nm. Motivated by this success we have investigated the use of a tri-band multilayer to increase the bandwidth while maintaini… more
Date: January 7, 2008
Creator: Jones, Juanita; Aquila, Andrew; Salmassi, Farhad & Gullikson, Eric
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EUV micro-exposure tool at 0.5 NA for sub-16 nm lithography

Description: The resolution limit of present 0.3 NA 13.5 nm wavelength micro-exposure tools is compared to next generation lithography research requirements. Findings suggest that a successor design is needed for patterning starting at the 16 nm semiconductor process technology node. A two-mirror 0.5 NA optical design is presented, and performance expectations are established from detailed optical and lithographic simulation. Here, we report on the results from a SEMATECH program to fabricate a projection o… more
Date: September 26, 2008
Creator: Goldstein, Michael; Hudyma, Russ; Naulleau, Patrick & Wurm, Stefan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

SOLAR NANTENNA ELECTROMAGNETIC COLLECTORS

Description: This research explores a new efficient approach for producing electricity from the abundant energy of the sun. A nanoantenna electromagnetic collector (NEC) has been designed, prototyped, and tested. Proof of concept has been validated. The device targets mid-infrared wavelengths where conventional photovoltaic (PV) solar cells do not respond but is abundant in solar energy. The initial concept of designing NEC antennas was based on scaling of radio frequency antenna theory. This approach has p… more
Date: August 1, 2008
Creator: Novack, Steven D.; Kotter, Dale K.; Slafer, Dennis & Pinhero, Patrick
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Actinic EUV mask inspection beyond 0.25 NA

Description: Operating at EUV wavelengths, the SEMATECH Berkeley Actinic Inspection Tool (AIT) is a zoneplate microscope that provides high quality aerial image measurements in routine operations for SEMATECH member companies. We have upgraded the optical performance of the AIT to provide multiple image magnifications, and several inspection NA values up to 0.35 NA equivalent (0.0875 mask-side). We report on the improved imaging capabilities including resolution below 100-nm on the mask side (25 nm, 4x wafe… more
Date: August 6, 2008
Creator: Goldberg, Kenneth A.; Mochi, Iacopo; Anderson, Erik H.; Rekawa, Seno B.; Kemp, Charles D.; Huh, S. et al.
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Partner: UNT Libraries Government Documents Department
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Pulse Analysis Spectroradiometer System for Measuring the Spectral Distribution of Flash Solar Simulators: Preprint

Description: Flashing artificial light sources are used extensively in photovoltaic module performance testing and plant production lines. There are several means of attempting to measure the spectral distribution of a flash of light; however, many of these approaches generally capture the entire pulse energy. We report here on the design and performance of a system to capture the waveform of flash at individual wavelengths of light. Any period within the flash duration can be selected, over which to integr… more
Date: July 1, 2008
Creator: Andreas, A. M. & Myers, D. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fabrication and characterization of a new high density Sc/Si multilayer sliced grating

Description: State of the art soft x-ray spectroscopy techniques like Resonant Inelastic X-ray Scattering (RIXS) require diffraction gratings which can provide extremely high spectral resolution of 105-106. This problem may be addressed with a sliced multilayer grating with an ultra-high groove density (up to 50,000 mm-1) proposed in the recent publication [Voronov, D. L., Cambie, R., Feshchenko, R. M., Gullikson, E., Padmore, H. A., Vinogradov, A. V., Yashchuk, V. V., Proc. SPIE 6705, 67050E (2007)]. It ha… more
Date: July 21, 2008
Creator: Source, Advanced Light; Voronov, Dmitriy L.; Cambie, Rossana; Gullikson, Eric; Yashchuk, Valeriy; Padmore, Howard et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tunable nanowire nonlinear optical probe

Description: One crucial challenge for subwavelength optics has been thedevelopment of a tunable source of coherent laser radiation for use inthe physical, information, and biological sciences that is stable at roomtemperature and physiological conditions. Current advanced near-fieldimaging techniques using fiber-optic scattering probes1,2 have alreadyachieved spatial resolution down to the 20-nm range. Recently reportedfar-field approaches for optical microscopy, including stimulatedemission depletion (STE… more
Date: February 18, 2008
Creator: Nakayama, Yuri; Pauzauskie, Peter J.; Radenovic, Aleksandra; Onorato, Robert M.; Saykally, Richard J.; Liphardt, Jan et al.
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Partner: UNT Libraries Government Documents Department
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Diffraction effects in coherent transition radiation diagnostics for sub-mm bunch length measurement

Description: Electrons crossing the boundary between different media generate bursts of transition radiation. In the case of bunches of N electrons, the radiation is coherent and has an N-squared enhancement at wavelengths related to the longitudinal bunch distribution. This coherent transition radiation has therefore attracted attention as an interceptive charged particle beam diagnostic technique. Many analytical descriptions have been devised describing the spectral distribution generated by electron bun… more
Date: September 1, 2008
Creator: Maxwell, T. J.; Mihalcea, D. & Piot, P.
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Partner: UNT Libraries Government Documents Department
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Verifying the Cosmological Utility of Type Ia Supernovae: Implications of a Dispersion in the Ultraviolet Spectra

Description: We analyze the mean rest-frame ultraviolet (UV) spectrum of Type Ia Supernovae (SNe) and its dispersion using high signal-to-noise ratio Keck-I/LRIS-B spectroscopy for a sample of 36 events at intermediate redshift (z=0.5) discovered by the Canada-France-Hawaii Telescope Supernova Legacy Survey (SNLS). We introduce a new method for removing host galaxy contamination in our spectra, exploiting the comprehensive photometric coverage of the SNLS SNe and their host galaxies, thereby providing the f… more
Date: February 28, 2008
Creator: Nugent, Peter E.; Ellis, R. S.; Sullivan, M.; Nugent, P. E.; Howell, D. A.; Gal-Yam, A. et al.
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Partner: UNT Libraries Government Documents Department
open access

Measurements of Coherent Synchrotron Radiation and its Impact on the LCLS Electron Beam

Description: In order to reach the high peak current required for an x-ray FEL, two separate magnetic dipole chicanes are used in the LCLS accelerator to compress the electron bunch length in stages. In these bunch compressors, coherent synchrotron radiation (CSR) can be emitted-induced either by a short electron bunch, or by any longitudinal density modulation that may be on the bunch. We present measurements, simulations, and analysis of (1) the CSR-induced energy loss, (2) the related transverse emittanc… more
Date: September 24, 2008
Creator: Bane, K. L. F.; Decker, F. J.; Ding, Y.; Dowell, D.; Emma, P.; Frisch, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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