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Reduction And Sequestration Of Pertechnetate To Technetium Dioxide And Protection From Reoxidation (open access)

Reduction And Sequestration Of Pertechnetate To Technetium Dioxide And Protection From Reoxidation

This effort is part of the technetium management initiative and provides data for the handling and disposition of technetium. To that end, the objective of this effort was to challenge tin(lI)apatite (Sn(II)apatite) against double-shell tank 241-AN-105 simulant spiked with pertechnetate (TcO{sub 4}). The Sn(II)apatite used in this effort was synthesized on site using a recipe developed at and provided by Sandia National Laboratories; the synthesis provides a high quality product while requiring minimal laboratory effort. The Sn(ll)apatite reduces pertechnetate from the mobile +7 oxidation state to the non-mobile +4 oxidation state. It also sequesters the technetium and does not allow for re-oxidization to the mobile +7 state under acidic or oxygenated conditions within the tested period of time (6 weeks). Previous work indicated that the Sn(II) apatite can achieve an ANSI leachability index in Cast Stone of 12.8. The technetium distribution coefficient for Sn(lI)apatite exhibited a direct correlation with the pH of the technetium-spiked simulant media.
Date: November 7, 2012
Creator: Duncan, J. B.; Johnson, J. M.; Moore, R. C.; Hagerty, K.; Rhodes, R. N.; Huber, H. J. et al.
System: The UNT Digital Library
Full toroidal imaging of non-axisymmetric plasma material interaction in the National Spherical Torus eXperiment divertor (open access)

Full toroidal imaging of non-axisymmetric plasma material interaction in the National Spherical Torus eXperiment divertor

None
Date: May 7, 2012
Creator: Scotti, F; Roquemore, A L & Soukhanovskii, V A
System: The UNT Digital Library
Gluons and the Quark Sea at High Energies: Distributions, Polarization, Tomography (open access)

Gluons and the Quark Sea at High Energies: Distributions, Polarization, Tomography

This report on the science case for an Electron-Ion Collider (EIC) is the result of a ten-week program at the Institute for Nuclear Theory (INT) in Seattle (from September 13-November 19, 2010), motivated by the need to develop a strong case for the continued study of the QCD description of hadron structure in the coming decades. Hadron structure in the valence quark region will be studied extensively with the Jefferson Lab 12 GeV science program, the subject of an INT program the previous year. The focus of the INT program was on understanding the role of gluons and sea quarks, the important dynamical degrees of freedom describing hadron structure at high energies. Experimentally, the most direct and precise way to access the dynamical structure of hadrons and nuclei at high energies is with a high luminosity lepton probe in collider mode. An EIC with optimized detectors offers enormous potential as the next generation accelerator to address many of the most important, open questions about the fundamental structure of matter. The goal of the INT program, as captured in the writeups in this report, was to articulate these questions and to identify golden experiments that have the greatest potential to provide …
Date: June 7, 2012
Creator: Boer, Daniel; Diehl, Markus; Milner, Richard; Venugopalan, Raju; Vogelsang, Werner; Kaplan, David et al.
System: The UNT Digital Library
The NIF 4.5-m nTOF Detectors (open access)

The NIF 4.5-m nTOF Detectors

The first several campaigns of laser fusion experiments at the National Ignition Facility (NIF) included a family of high-sensitivity scintillator/photodetector neutron-time-of-flight (nTOF) detectors for measuring DD and DT neutron yields. The detectors provided consistent neutron yield benchmarks from below 1E9 (DD) to nearly 1E15 (DT). The detectors demonstrated DT yield measurement precisions better than 5%, but the absolute accuracy relies on cross calibration with independent measurements of absolute neutron yield. The 4.5-m nTOF data have provided a useful testbed for testing improvements in nTOF data processing, especially with respect to improving the accuracies of the detector impulse response functions. The resulting improvements in data analysis methods have produced more accurate results. In summary, results from the NIF 4.5-m nTOF detectors have provided consistent measurements of DD and DT neutron yields from laser-fusion implosions.
Date: May 7, 2012
Creator: Moran, M. J.; Bond, E. J.; Clancy, T. J.; Eckart, M. J.; Khater, H. Y. & Glebov, V. Y.
System: The UNT Digital Library
Robust Optical Richness Estimation with Reduced Scatter (open access)

Robust Optical Richness Estimation with Reduced Scatter

Reducing the scatter between cluster mass and optical richness is a key goal for cluster cosmology from photometric catalogs. We consider various modifications to the red-sequence matched filter richness estimator of Rozo et al. (2009b), and evaluate their impact on the scatter in X-ray luminosity at fixed richness. Most significantly, we find that deeper luminosity cuts can reduce the recovered scatter, finding that {sigma}{sub ln L{sub X}|{lambda}} = 0.63 {+-} 0.02 for clusters with M{sub 500c} {approx}> 1.6 x 10{sup 14} h{sub 70}{sup -1} M{sub {circle_dot}}. The corresponding scatter in mass at fixed richness is {sigma}{sub ln M|{lambda}} {approx} 0.2-0.3 depending on the richness, comparable to that for total X-ray luminosity. We find that including blue galaxies in the richness estimate increases the scatter, as does weighting galaxies by their optical luminosity. We further demonstrate that our richness estimator is very robust. Specifically, the filter employed when estimating richness can be calibrated directly from the data, without requiring a-priori calibrations of the red-sequence. We also demonstrate that the recovered richness is robust to up to 50% uncertainties in the galaxy background, as well as to the choice of photometric filter employed, so long as the filters span the 4000 {angstrom} …
Date: June 7, 2012
Creator: Rykoff, E. S.; Koester, B. P.; Rozo, E.; Annis, J.; Evrard, A. E.; Hansen, S. M. et al.
System: The UNT Digital Library
Rhapsody: II. Subhalo Properties and the Impact of Tidal Stripping from a Statistical Sample of Cluster-Size Halos (open access)

Rhapsody: II. Subhalo Properties and the Impact of Tidal Stripping from a Statistical Sample of Cluster-Size Halos

Discusses the properties of subhalos in cluster-size halos, using a high resolution statistical sample: the RHAPSODY simulations.
Date: December 7, 2012
Creator: Wu, Hao-Yi; Hahn, Oliver; Wechsler, Risa H.; Behroozi, Peter S. & Mao, Yao-Yuan
System: The UNT Digital Library
Empirical Model for Formulation of Crystal-Tolerant Hlw Glasses (open access)

Empirical Model for Formulation of Crystal-Tolerant Hlw Glasses

Historically, high-level waste (HLW) glasses have been formulated with a low liquideus temperature (T{sub L}), or temperature at which the equilibrium fraction of spinel crystals in the melt is below 1 vol % (T{sub 0.01}), nominally below 1050 C. These constraints cannot prevent the accumulation of large spinel crystals in considerably cooler regions ({approx} 850 C) of the glass discharge riser during melter idling and significantly limit the waste loading, which is reflected in a high volume of waste glass, and would result in high capital, production, and disposal costs. A developed empirical model predicts crystal accumulation in the riser of the melter as a function of concentration of spinel-forming components in glass, and thereby provides guidance in formulating crystal-tolerant glasses that would allow high waste loadings by keeping the spinel crystals small and therefore suspended in the glass.
Date: March 7, 2012
Creator: Kruger, A. A.; Matyas, J.; Huckleberry, A. R.; Vienna, J. D. & Rodriguez, C. A.
System: The UNT Digital Library
Rhapsody: I. Structural Properties and Formation History from a Statistical Sample of Re-simulated Cluster-size Halos (open access)

Rhapsody: I. Structural Properties and Formation History from a Statistical Sample of Re-simulated Cluster-size Halos

Presents the first results from the RHAPSODY cluster re-simulation project.
Date: December 7, 2012
Creator: Wu, Hao-Yi; Hahn, Oliver; Wechsler, Risa H.; Mao, Yao-Yuan & Behroozi, Peter S.
System: The UNT Digital Library
The BigBoss Experiment (open access)

The BigBoss Experiment

BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra over a wavelength range from 340 nm to 1060 nm, with a resolution R = {lambda}/{Delta}{lambda} = 3000-4800. Using data from imaging surveys that are already underway, spectroscopic targets are selected that trace the underlying dark matter distribution. In particular, targets include luminous red galaxies (LRGs) up to z = 1.0, extending the BOSS LRG survey in both redshift and survey area. To probe the universe out to even higher redshift, BigBOSS will target bright [OII] emission line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy redshifts are obtained to measure the BAO feature, trace the matter power spectrum at smaller scales, and detect redshift space distortions. BigBOSS will provide additional constraints on early dark energy and on the curvature of …
Date: June 7, 2012
Creator: Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J. et al.
System: The UNT Digital Library
Color-kinematics duality and double-copy construction for amplitudes from higher-dimension operators (open access)

Color-kinematics duality and double-copy construction for amplitudes from higher-dimension operators

None
Date: August 7, 2012
Creator: Broedel, Johannes & Dixon, Lance J.
System: The UNT Digital Library
Self-Consistency Requirements of the Re normalization Group for Setting the Re normalization Scale (open access)

Self-Consistency Requirements of the Re normalization Group for Setting the Re normalization Scale

None
Date: August 7, 2012
Creator: Brodsky, Stanley J. & Wu, Xing-Gang
System: The UNT Digital Library
Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission (open access)

Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission

We report on a detailed investigation of the {gamma}-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed {gamma}-ray emission reveals in addition possible flux variability in both sources. No statistically significant {gamma}-ray detection of the other BLRGs was however found in the considered dataset. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in {gamma}-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the {gamma}-ray flux variability and a number of other arguments presented, indicate that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found none were detected in {gamma}-rays. A simple phenomenological hybrid model applied for the broad-band emission of the discussed radio-loud and …
Date: June 7, 2012
Creator: Kataoka, J.; Stawarz, L.; Takahashi, Y.; Cheung, C. C.; Hayashida, M.; Grandi, P. et al.
System: The UNT Digital Library
Explosive Pulsed Power Experimental Capability at LLNL (open access)

Explosive Pulsed Power Experimental Capability at LLNL

None
Date: November 7, 2012
Creator: White, A. D.; Milhous, D. P.; Goerz, D. A.; Anderson, R. A.; Ferriera, T. J.; Speer, R. D. et al.
System: The UNT Digital Library
An X-Band Gun Test Area at SLAC (open access)

An X-Band Gun Test Area at SLAC

The X-Band Test Area (XTA) is being assembled in the NLCTA tunnel at SLAC to serve as a test facility for new RF guns. The first gun to be tested will be an upgraded version of the 5.6 cell, 200 MV/m peak field X-band gun designed at SLAC in 2003 for the Compton Scattering experiment run in ASTA. This new version includes some features implemented in 2006 on the LCLS gun such as racetrack couplers, increased mode separation and elliptical irises. These upgrades were developed in collaboration with LLNL since the same gun will be used in an injector for a LLNL Gamma-ray Source. Our beamline includes an X-band acceleration section which takes the electron beam up to 100 MeV and an electron beam measurement station. Other X-Band guns such as the UCLA Hybrid gun will be characterized at our facility.
Date: September 7, 2012
Creator: Limborg-Deprey, C.; Adolphsen, C.; Chu, T. S.; Dunning, M. P.; Jobe, R. K.; Jongewaard, E. N. et al.
System: The UNT Digital Library
Symbolic Analysis of Concurrency Errors in OpenMP Programs (open access)

Symbolic Analysis of Concurrency Errors in OpenMP Programs

None
Date: November 7, 2012
Creator: Ma, H.; Wang, L.; Liao, C.; Quinlan, D. & Yang, Z.
System: The UNT Digital Library
Single-valued Harmonic Polylogarithms and the Multi-Regge Limit (open access)

Single-valued Harmonic Polylogarithms and the Multi-Regge Limit

None
Date: August 7, 2012
Creator: Dixon, Lance J.; Duhr, Claude & Pennington, Jeffrey
System: The UNT Digital Library
The Evaluation of the Heat Loading from Steady, Transient, and Off-Normal Conditions in ARIES Power Plants (open access)

The Evaluation of the Heat Loading from Steady, Transient, and Off-Normal Conditions in ARIES Power Plants

The heat loading on plasma facing components (PFCs) provides a critical limitation for design and operation of the first wall, divertor, and other special components. Power plants will have high power entering the scrape-off layer and transporting to the first wall and divertor. Although the design for steady heat loads is understood, the approach for transient and offnormal loading is not. The characterization of heat loads developed for ITER1 can be applied to power plants to better develop the operating space of viable solutions and point to research focus areas.
Date: September 7, 2012
Creator: C.E. Kessel, M.S. Tillack and J. Blanchard
System: The UNT Digital Library
Rho Meson Diffraction off Au Nuclei (open access)

Rho Meson Diffraction off Au Nuclei

N/A
Date: April 7, 2012
Creator: Debbe, Ramiro
System: The UNT Digital Library
A Fixed-Target ExpeRiment at the LHC (AFTER@LHC) : Luminosities, Target Polarisation and a Selection of Physics Studies (open access)

A Fixed-Target ExpeRiment at the LHC (AFTER@LHC) : Luminosities, Target Polarisation and a Selection of Physics Studies

None
Date: August 7, 2012
Creator: Lansberg, J.P.; Chambert, V.; Didelez, J.P.; Genolini, B.; Hadjidakis, C.; Rosier, P. et al.
System: The UNT Digital Library
What Scientific Applications can Benefit from Hardware Transactional Memory? (open access)

What Scientific Applications can Benefit from Hardware Transactional Memory?

None
Date: May 7, 2012
Creator: Schindewolf, M; Bihari, B; Gyllenhaal, J; Schulz, M; Wang, A & Karl, W
System: The UNT Digital Library
Nuclear Plasma Interactions on NIF (open access)

Nuclear Plasma Interactions on NIF

None
Date: November 7, 2012
Creator: Hoffman, R; Zimmerman, G; Chen, M & Cerjan, C
System: The UNT Digital Library
Discovery of Very High Energy Gamma-Ray Emission from 1FGL J2001.1 4351 by MAGIC (open access)

Discovery of Very High Energy Gamma-Ray Emission from 1FGL J2001.1 4351 by MAGIC

We report the discovery of Very High Energy (VHE; >100 GeV) gamma-ray emission from the source 1FGL J2001.1+4351, (RA 20 01 13.5, dec 43 53 02.8, J2000), which is positionally consistent with the location of the flat spectrum radio source MG4 J200112+4352 (RA 20 01 12.9, dec 43 52 52.8, J2000). The VHE detection is based on a 1.5 hour-long observation performed on July 16th in stereoscopic mode with the two 17m diameter imaging Cherenkov telescopes on La Palma, Canary Islands, Spain. The preliminary analysis of the MAGIC data using the standard cuts optimized for soft energy spectra sources yields a detection of 125 gamma-rays above 90 GeV, corresponding to a pre-trail statistical significance of 7.6 standard deviations. The observed flux is estimated to be {approx}20% of the Crab nebula flux above 100 GeV. Earlier MAGIC observations indicated a substantially lower flux; hence indicating that the source is variable on a few days timescale.
Date: May 7, 2012
Creator: Berger, Karsten; Paneque, David & Giavitto, Gianluca
System: The UNT Digital Library
Enhanced NIF Neutron Activation Diagnostics (open access)

Enhanced NIF Neutron Activation Diagnostics

None
Date: May 7, 2012
Creator: Yeamans, C B; Bleuel, D L & Bernstein, L A
System: The UNT Digital Library
Experimental techniques for measuring Rayleigh-Taylor instability in inertial confinement fusion (ICF) (open access)

Experimental techniques for measuring Rayleigh-Taylor instability in inertial confinement fusion (ICF)

Rayleigh-Taylor (RT) instability is one of the major concerns in inertial confinement fusion (ICF) because it amplifies target modulations in both acceleration and deceleration phases of implosion, which leads to shell disruption and performance degradation of imploding targets. This article reviews experimental results of the RT growth experiments performed on OMEGA laser system, where targets were driven directly with laser light. RT instability was studied in the linear and nonlinear regimes. The experiments were performed in acceleration phase, using planar and spherical targets, and in deceleration phase of spherical implosions, using spherical shells. Initial target modulations consisted of 2-D pre-imposed modulations, and 2-D and 3-D modulations imprinted on targets by the non-uniformities in laser drive. In planar geometry, the nonlinear regime was studied using 3-D modulations with broadband spectra near nonlinear saturation levels. In acceleration-phase, the measured modulation Fourier spectra and nonlinear growth velocities are in good agreement with those predicted by Haan's model [Haan S W 1989 Phys. Rev. A 39 5812]. In a real-space analysis, the bubble merger was quantified by a self-similar evolution of bubble size distributions [Oron D et al 2001 Phys. Plasmas 8, 2883]. The 3-D, inner-surface modulations were measured to grow throughout the deceleration …
Date: June 7, 2012
Creator: Smalyuk, V A
System: The UNT Digital Library