Dissipative Cryogenic Filters with Zero DC Resistance (open access)

Dissipative Cryogenic Filters with Zero DC Resistance

The authors designed, implemented and tested cryogenic RF filters with zero DC resistance, based on wires with a superconducting core inside a resistive sheath. The superconducting core allows low frequency currents to pass with negligible dissipation. Signals above the cutoff frequency are dissipated in the resistive part due to their small skin depth. The filters consist of twisted wire pairs shielded with copper tape. Above approximately 1 GHz, the attenuation is exponential in {radical}{omega}, as typical for skin depth based RF filters. By using additional capacitors of 10 nF per line, an attenuation of at least 45 dB above 10 MHz can be obtained. Thus, one single filter stage kept at mixing chamber temperature in a dilution refrigerator is sufficient to attenuate room temperature black body radiation to levels corresponding to 10 mK above about 10 MHz.
Date: April 22, 2008
Creator: Bluhm, Hendrik; Moler, Kathryn A. & /Stanford U., Appl. Phys. Dept
System: The UNT Digital Library
Information Resources in High-Energy Physics: Surveying the Present Landscape and Charting the Future Course (open access)

Information Resources in High-Energy Physics: Surveying the Present Landscape and Charting the Future Course

Access to previous results is of paramount importance in the scientific process. Recent progress in information management focuses on building e-infrastructures for the optimization of the research workflow, through both policy-driven and user-pulled dynamics. For decades, High-Energy Physics (HEP) has pioneered innovative solutions in the field of information management and dissemination. In light of a transforming information environment, it is important to assess the current usage of information resources by researchers and HEP provides a unique test-bed for this assessment. A survey of about 10% of practitioners in the field reveals usage trends and information needs. Community-based services, such as the pioneering arXiv and SPIRES systems, largely answer the need of the scientists, with a limited but increasing fraction of younger users relying on Google. Commercial services offered by publishers or database vendors are essentially unused in the field. The survey offers an insight into the most important features that users require to optimize their research workflow. These results inform the future evolution of information management in HEP and, as these researchers are traditionally 'early adopters' of innovation in scholarly communication, can inspire developments of disciplinary repositories serving other communities.
Date: April 22, 2008
Creator: Gentil-Beccot, Anne; Mele, Salvatore; Holtkamp, Annette; O'Connell, Heath B. & Brooks, Travis C.
System: The UNT Digital Library
Observation of B^+\to\eta\rho^+ and Search for B^0 Decays to\eta^\prime\eta, \eta\pi^0, \eta^\prime\pi^0, and \omega\pi^0 (open access)

Observation of B^+\to\eta\rho^+ and Search for B^0 Decays to\eta^\prime\eta, \eta\pi^0, \eta^\prime\pi^0, and \omega\pi^0

The authors present measurements of branching fractions for five B-meson decays to two-body charmless final states. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 459 million B{bar B} pairs. The results for branching fractions are, in units of 10{sup -6} (upper limits at 90% C.L.): {Beta}(B{sup +} {yields} {eta}{rho}{sup +}) = 9.9 {+-} 1.2 {+-} 0.8, {Beta}(B{sup 0} {yields} {eta}{prime}{eta}) = 0.5 {+-} 0.4 {+-} 0.1 (< 1.2), {Beta}(B{sup 0} {yields} {eta}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), {Beta}(B{sup 0} {yields} {eta}{prime}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), and {Beta}(B{sup 0}{sup 0} {yields} {omega}{pi}{sup 0}) = {eta}{rho}{sup +} mode, they measure the charge asymmetry {Alpha}{sub ch} (B{sup +} {yields} {eta}{rho}{sup +}) = 0.13 {+-} 0.11 {+-} 0.02.
Date: April 22, 2008
Creator: Aubert, Bernard; Bona, Marcella; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
System: The UNT Digital Library
ATCA for Machines-- Advanced Telecommunications Computing Architecture (open access)

ATCA for Machines-- Advanced Telecommunications Computing Architecture

The Advanced Telecommunications Computing Architecture is a new industry open standard for electronics instrument modules and shelves being evaluated for the International Linear Collider (ILC). It is the first industrial standard designed for High Availability (HA). ILC availability simulations have shown clearly that the capabilities of ATCA are needed in order to achieve acceptable integrated luminosity. The ATCA architecture looks attractive for beam instruments and detector applications as well. This paper provides an overview of ongoing R&D including application of HA principles to power electronics systems.
Date: April 22, 2008
Creator: Larsen, R.S.
System: The UNT Digital Library
Testing the Standard Model with Radiative Penguin Decays at BaBar (open access)

Testing the Standard Model with Radiative Penguin Decays at BaBar

The author discusses two recent results in b {yields} s{gamma} decays from BABAR. The first is a measurement of the branching fraction and photon energy spectrum in the B meson frame of the decay B {yields} X{sub s{gamma}}. The second result probes the photon polarization via time-dependent CP violation in neutral B decays to K*{sup 0}{gamma}.
Date: April 22, 2008
Creator: Tuggle, J
System: The UNT Digital Library
Suzaku Observation of TeV Blazar the 1ES 1218+304: Clues on Particle Acceleration in an Extreme TeV Blazar (open access)

Suzaku Observation of TeV Blazar the 1ES 1218+304: Clues on Particle Acceleration in an Extreme TeV Blazar

We observed the TeV blazar 1ES 1218+304 with the X-ray astronomy satellite Suzaku in May 2006. At the beginning of the two-day continuous observation, we detected a large flare in which the 5-10 keV flux changed by a factor of {approx}2 on a timescale of 5 x 10{sup 4} s. During the flare, the increase in the hard X-ray flux clearly lagged behind that observed in the soft X-rays, with the maximum lag of 2.3 x 10{sup 4} s observed between the 0.3?1 keV and 5?10 keV bands. Furthermore we discovered that the temporal profile of the flare clearly changes with energy, being more symmetric at higher energies. From the spectral fitting of multi-wavelength data assuming a one-zone, homogeneous synchrotron self-Compton model, we obtain B {approx} 0.047 G, emission region size R = 3.0 x 10{sup 16} cm for an appropriate beaming with a Doppler factor of {delta} = 20. This value of B is in good agreement with an independent estimate through the model fit to the observed time lag ascribing the energy-dependent variability to differential acceleration timescale of relativistic electrons provided that the gyro-factor {zeta} is 10{sup 5}.
Date: April 22, 2008
Creator: Sato, R.; Kataoka, J.; Takahashi, T.; Madejski, G. M.; Rugamer, S. & Wagner, S. J.
System: The UNT Digital Library
Improved Measurement of the CKM Angle gamma in B^-+ to D^(*) K^(*)-+Decays with a Dalitz Plot Analysis of D Decays to K_S^0 pi+ pi- and K_S^0 K+ K- (open access)

Improved Measurement of the CKM Angle gamma in B^-+ to D^(*) K^(*)-+Decays with a Dalitz Plot Analysis of D Decays to K_S^0 pi+ pi- and K_S^0 K+ K-

We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{bar B} pairs collected by the BABAR detector, we measure {gamma} = (76 {+-} 22 {+-} 5{+-} 5){sup o} (mod 180{sup o}), where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the uncertainty on the description of the Dalitz plot distributions. The corresponding two standard deviation region is 29{sup o} < {gamma} < 122{sup o}. This result has a significance of direct CP violation ({gamma} {ne} 0) of 3.0 standard deviations.
Date: April 22, 2008
Creator: Aubert, B.
System: The UNT Digital Library
Real-time Data Access Monitoring in Distributed, Multi-petabyte Systems (open access)

Real-time Data Access Monitoring in Distributed, Multi-petabyte Systems

Petascale systems are in existence today and will become common in the next few years. Such systems are inevitably very complex, highly distributed and heterogeneous. Monitoring a petascale system in real-time and understanding its status at any given moment without impacting its performance is a highly intricate task. Common approaches and off-the-shelf tools are either unusable, do not scale, or severely impact the performance of the monitored servers. This paper describes unobtrusive monitoring software developed at Stanford Linear Accelerator Center (SLAC) for a highly distributed petascale production data set. The paper describes the employed solutions, the lessons learned, the problems still to be addressed, and explains how the system can be reused elsewhere.
Date: April 22, 2008
Creator: Azemoon, Tofigh; Becla, Jacek, a=Hanushevsky, Andrew & Turri, Massimiliano
System: The UNT Digital Library
Two-dimensional Vortex Behavior in Highly Underdoped YBa_2Cu_3O_{6+x} Observed byScanning Hall Probe Microscopy (open access)

Two-dimensional Vortex Behavior in Highly Underdoped YBa_2Cu_3O_{6+x} Observed byScanning Hall Probe Microscopy

We report scanning Hall probe microscopy of highly underdoped superconducting YBa{sub 2}Cu{sub 3}O{sub 6+z} with T{sub c} ranging from 5 to 15 K which showed distinct flux bundles with less than one superconducting flux quantum ({Phi}{sub 0}) through the sample surface. The sub-{Phi}{sub 0} features occurred more frequently for lower T{sub c}, were more mobile than conventional vortices, and occurred more readily when the sample was cooled with an in-plane field component. We show that these features are consistent with kinked stacks of pancake vortices.
Date: April 22, 2008
Creator: Guikema, J.W.; Bluhm, Hendrik; /Stanford U., Appl. Phys. Dept.; Bonn, D.A.; Liang, Ruixing; Hardy, W.N. et al.
System: The UNT Digital Library
TEMPERATURE PREDICTION IN 3013 CONTAINERS IN K AREA MATERIAL STORAGE (KAMS) FACILITY USING REGRESSION METHODS (open access)

TEMPERATURE PREDICTION IN 3013 CONTAINERS IN K AREA MATERIAL STORAGE (KAMS) FACILITY USING REGRESSION METHODS

3013 containers are designed in accordance with the DOE-STD-3013-2004. These containers are qualified to store plutonium (Pu) bearing materials such as PuO2 for 50 years. DOT shipping packages such as the 9975 are used to store the 3013 containers in the K-Area Material Storage (KAMS) facility at Savannah River Site (SRS). DOE-STD-3013-2004 requires that a comprehensive surveillance program be set up to ensure that the 3013 container design parameters are not violated during the long term storage. To ensure structural integrity of the 3013 containers, thermal analyses using finite element models were performed to predict the contents and component temperatures for different but well defined parameters such as storage ambient temperature, PuO{sub 2} density, fill heights, weights, and thermal loading. Interpolation is normally used to calculate temperatures if the actual parameter values are different from the analyzed values. A statistical analysis technique using regression methods is proposed to develop simple polynomial relations to predict temperatures for the actual parameter values found in the containers. The analysis shows that regression analysis is a powerful tool to develop simple relations to assess component temperatures.
Date: April 22, 2008
Creator: Gupta, N
System: The UNT Digital Library
Nonlocal exchange correlation in screened-exchange densityfunctional methods (open access)

Nonlocal exchange correlation in screened-exchange densityfunctional methods

We present a systematic study on the exchange-correlationeffects in screened-exchange local density functional method. Toinvestigate the effects of the screened-exchange potential in the bandgap correction, we have compared the exchange-correlation potential termin the sX-LDA formalism with the self-energy term in the GWapproximation. It is found that the band gap correction of the sX-LDAmethod primarily comes from the downshift of valence band states,resulting from the enhancement of bonding and the increase of ionizationenergy. The band gap correction in the GW method, on the contrary, comesin large part from the increase of theconduction band energies. We alsostudied the effects of the screened-exchange potential in the totalenergy by investigating the exchange-correlation hole in comparison withquantum Monte Carlo calculations. When the Thomas-Fermi screening isused, the sX-LDA method overestimates (underestimates) theexchange-correlation hole in short (long) range. From theexchange-correlation energy analysis we found that the LDA method yieldsbetter absolute total energy than sX-LDA method.
Date: April 22, 2007
Creator: Lee, Byounghak; Wang, Lin-Wang; Spataru, Catalin D. & Louie,Steven G.
System: The UNT Digital Library
High-Level Application Framework for LCLS (open access)

High-Level Application Framework for LCLS

A framework for high level accelerator application software is being developed for the Linac Coherent Light Source (LCLS). The framework is based on plug-in technology developed by an open source project, Eclipse. Many existing functionalities provided by Eclipse are available to high-level applications written within this framework. The framework also contains static data storage configuration and dynamic data connectivity. Because the framework is Eclipse-based, it is highly compatible with any other Eclipse plug-ins. The entire infrastructure of the software framework will be presented. Planned applications and plug-ins based on the framework are also presented.
Date: April 22, 2008
Creator: Chu, P; Chevtsov, S.; Fairley, D.; Larrieu, C.; Rock, J.; Rogind, D. et al.
System: The UNT Digital Library
12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments (open access)

12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments

A high contrast 12.6 keV Kr K{alpha} source has been demonstrated on the petawatt-class Titan laser facility. The contrast ratio (K{alpha} to continuum) is 65, with a competitive ultra short pulse laser to x-ray conversion efficiency of 10{sup -5}. Filtered shadowgraphy indicates that the Kr K{alpha} and K{beta} x-rays are emitted from a roughly 1 x 2 mm emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70 eV (i.e. mean ionization state 13-16), based on the observed ratio of K{alpha} to K{beta}. Kr gas jets provide a debris-free high energy K{alpha} source for time-resolved diagnosis of dense matter.
Date: April 22, 2008
Creator: Kugland, N.; Constantin, C. G.; Niemann, C.; Neumayer, P.; Chung, H.; Doppner, T. et al.
System: The UNT Digital Library
Resolving the Nature of the LMC Microlensing Event LMC-5 (open access)

Resolving the Nature of the LMC Microlensing Event LMC-5

The authors present the results from an analysis of Hubble Space Telescope High Resolution Camera data for the Large Magellanic Cloud microlensing event MACHO-LMC-5. By determining the parallax and proper motion of this object they find that the lens is an M dwarf star at a distance of 578{sub -53}{sup +65}pc with a proper motion of 21.39 {+-} 0.04 mas/yr. Based on the kinematics and location of this star is it more likely to be part of the Galactic thick disk than thin disk population. They confirm that the microlensing event LMC-5 is a jerk-parallax microlensing event.
Date: April 22, 2004
Creator: Drake, A J; Cook, K H & Keller, S C
System: The UNT Digital Library
Evaluation Of Microdosing Strategies For Studies In Preclinical Drug Development: Demonstration Of Linear Pharmacokinetics In Dogs Of A Nucleoside Analogue Over A 50-Fold Dose Range (open access)

Evaluation Of Microdosing Strategies For Studies In Preclinical Drug Development: Demonstration Of Linear Pharmacokinetics In Dogs Of A Nucleoside Analogue Over A 50-Fold Dose Range

The technique of accelerator mass spectrometry (AMS) was validated successfully and utilized to study the pharmacokinetics and disposition in dogs of a preclinical drug candidate (Compound A), after oral and intravenous administration. The primary objective of this study was to examine whether Compound A displayed linear kinetics across sub-pharmacological (microdose) and pharmacological dose ranges in an animal model, prior to initiation of a human microdose study. The AMS-derived disposition properties of Compound A were comparable to data obtained via conventional techniques such as LC-MS/MS and liquid scintillation counting analyses. Thus, Compound A displayed multiphasic kinetics and possessed low plasma clearance (4.4 mL/min/kg), a long terminal elimination half-life (19.4 hr) and high oral bioavailability (82%). Currently there are no published comparisons of the kinetics of a pharmaceutical compound at pharmacological versus sub-pharmacological doses employing microdosing strategies. The present study thus provides the first description of the pharmacokinetics of a drug candidate assessed under these two dosing regimens. The data demonstrated that the pharmacokinetic properties of Compound A were similar following dosing at 0.02 mg/kg as at 1 mg/kg, indicating that in the case of Compound A, the kinetics of absorption, distribution and elimination in the dog appear to be linear across …
Date: April 22, 2004
Creator: Sandhu, P; Vogel, J S; Rose, M J; Ubick, E A; Brunner, J E; Wallace, M A et al.
System: The UNT Digital Library
Numerical Simulations of Shock-Induced Mixing and Combustion (open access)

Numerical Simulations of Shock-Induced Mixing and Combustion

In this paper we use numerical simulation to investigate shock-induced ignition and combustion of a hydrocarbon gas. The focus of this paper is on quantifying the effect of fidelity in the chemical kinetics on the overall solution. We model the system using the compressible Navier Stokes equations for a reacting mixture. These equations express conservation of species mass, momentum, total energy.
Date: April 22, 2003
Creator: Bell, J B; Day, M & Kuhl, A L
System: The UNT Digital Library
Search for Second-Class Currents in tau- -> omega.pi-.nu_tau (open access)

Search for Second-Class Currents in tau- -> omega.pi-.nu_tau

We report an analysis of {tau}{sup -} decaying into {omega}{pi}{sup -} {nu}{sub {tau}} with {omega} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} using a data sample containing nearly 320 million {tau} pairs collected with the BABAR detector at the PEP-II B-Factory. We find no evidence for second-class currents and we set an upper limit of 0.69% at 90% confidence level for the fraction of second-class currents in this decay mode.
Date: April 22, 2009
Creator: Aubert, B.
System: The UNT Digital Library
Decamethylytterbocene Complexes of Bipyridines and Diazabutadienes: Multiconfigurational Ground States and Open-Shell Singlet Formation (open access)

Decamethylytterbocene Complexes of Bipyridines and Diazabutadienes: Multiconfigurational Ground States and Open-Shell Singlet Formation

Partial ytterbium f-orbital occupancy (i.e., intermediate valence) and open-shell singlet formation are established for a variety of bipyridine and diazabutadiene adducts with decamethylytterbocene, (C5Me5)2Yb, abbreviated as Cp*2Yb. Data used to support this claim include ytterbium valence measurements using Yb LIII-edge X-ray absorption near-edge structure spectroscopy, magnetic susceptibility, and complete active space self-consistent field (CASSCF) multiconfigurational calculations, as well as structural measurements compared to density functional theory calculations. The CASSCF calculations indicate that the intermediate valence is the result of a multiconfigurational ground-state wave function that has both an open-shell singlet f13(?*)1, where pi* is the lowest unoccupied molecular orbital of the bipyridine or dpiazabutadiene ligands, and a closed-shell singlet f14 component. A number of other competing theories for the unusual magnetism in these materials are ruled out by the lack of temperature dependence of the measured intermediate valence. These results have implications for understanding chemical bonding not only in organolanthanide complexes but also for f-element chemistry in general, as well as understanding magnetic interactions in nanoparticles and devices.
Date: April 22, 2009
Creator: Booth, Corwin H.; Walter, Marc D.; Kazhdan, Daniel; Hu, Yung-Jin; Lukens, Wayne W.; Bauer, Eric D. et al.
System: The UNT Digital Library
Importance of Plasma Response to Non-axisymmetric Perturbations in Tokamaks (open access)

Importance of Plasma Response to Non-axisymmetric Perturbations in Tokamaks

Tokamaks are sensitive to deviations from axisymmetry as small as δB=B0 ~ 10-4. These non-axisymmetric perturbations greatly modify plasma confinement and performance by either destroying magnetic surfaces with subsequent locking or deforming magnetic surfaces with associated non-ambipolar transport. The Ideal Perturbed Equilibrium Code (IPEC) calculates ideal perturbed equilibria and provides important basis for understanding the sensitivity of tokamak plasmas to perturbations. IPEC calculations indicate that the ideal plasma response, or equiva- lently the effect by ideally perturbed plasma currents, is essential to explain locking experiments on National Spherical Torus eXperiment (NSTX) and DIII-D. The ideal plasma response is also important for Neoclassical Toroidal Viscosity (NTV) in non-ambipolar transport. The consistency between NTV theory and magnetic braking experiments on NSTX and DIII-D can be improved when the variation in the field strength in IPEC is coupled with generalized NTV theory. These plasma response effects will be compared with the previous vacuum superpositions to illustrate the importance. However, plasma response based on ideal perturbed equilibria is still not suffciently accurate to predict the details of NTV transport, and can be inconsistent when currents associated with a toroidal torque become comparable to ideal perturbed currents.
Date: April 22, 2009
Creator: Jong-kyu Park, Allen H. Boozer, Jonathan E. Menard, Andrea M. Garofalo, Michael J. Schaffer, Richard J. Hawryluk, Stanley M. Kaye, Stefan P. Gerhardt, Steve A. Sabbagh, and the NSTX Team
System: The UNT Digital Library
Bounding CKM Mixing with a Fourth Family (open access)

Bounding CKM Mixing with a Fourth Family

CKM mixing between third family quarks and a possible fourth family is constrained by global fits to the precision electroweak data. The dominant constraint is from nondecoupling oblique corrections rather than the vertex correction to Z {yields} {bar b}b used in previous analyses. The possibility of large mixing suggested by some recent analyses of FCNC processes is excluded, but 3-4 mixing of the same order as the Cabbibo mixing of the first two families is allowed.
Date: April 22, 2009
Creator: Chanowitz, Michael S.
System: The UNT Digital Library
Little Supersymmetry and the Supersymmetric Little Hierarchy Problem (open access)

Little Supersymmetry and the Supersymmetric Little Hierarchy Problem

The current experimental lower bound on the Higgs mass significantly restricts the allowed parameter space in most realistic supersymmetric models, with the consequence that these models exhibit significant fine-tuning. We propose a solution to this `supersymmetric little hierarchy problem'. We consider scenarios where the stop masses are relatively heavy - in the 500 GeV to a TeV range. Radiative stability of the Higgs soft mass against quantum corrections from the top quark Yukawa coupling is achieved by imposing a global SU(3) symmetry on this interaction. This global symmetry is only approximate - it is not respected by the gauge interactions. A subgroup of the global symmetry is gauged by the familiar SU(2) of the Standard Model. The physical Higgs is significantly lighter than the other scalars because it is the pseudo-Goldstone boson associated with the breaking of this symmetry. Radiative corrections to the Higgs potential naturally lead to the right pattern of gauge and global symmetry breaking. We show that both the gauge and global symmetries can be embedded into a single SU(6) grand unifying group, thereby maintaining the prediction of gauge coupling unification. Among the firm predictions of this class of models are new states with the quantum numbers …
Date: April 22, 2004
Creator: Birkedal, Andreas; Chacko, Z. & Gaillard, Mary K.
System: The UNT Digital Library
Local structure and site occupancy of Cd and Hg substitutions in CeTIn_5 (T=Co, Rh, Ir) (open access)

Local structure and site occupancy of Cd and Hg substitutions in CeTIn_5 (T=Co, Rh, Ir)

The CeTIn_5 superconductors (T=Co, Rh, or Ir) have generated great interest due to their relatively high transition temperatures, non-Fermi liquid behavior, and their proximity to antiferromagnetic order and quantum critical points. In contrast to small changes with the T-species, electron doping in CeT(In_1-x M_x)_5 with $M$=Sn and hole doping with Cd or Hg have a dramatic effect on the electronic properties at very low concentrations. The present work reports local structure measurements usingthe extended x-ray absorption fine-structure (EXAFS) technique that address the substituent atom distribution as a function of T, M, and x, in the vicinity of the superconducting phase. Together with previous measurements for M=Sn, the proportion of the $M$ atom residing on the In(1) site, f_\textrm In(1), increases in the order M=Cd, Sn, and Hg, ranging from about 40\percent to 70percent, showing a strong preference for each of these substituents to occupy the In(1) site (random occupation = 20percent). In addition, f_In(1) ranges from 70percent to 100percent for M=Hg in the order T=Co,Rh, and Ir. These fractions track the changes in the atomic radii of the various species, and help explain the sharp dependence of $T_c$ on substituting into the In site. However, it is difficult to reconcile …
Date: April 22, 2009
Creator: Booth, Corwin H.; Bauer, Eric. D.; Bianchi, Andrea D.; Ronning, Fillip; Thompson, Joe D.; Sarrao, John L. et al.
System: The UNT Digital Library
Extension of the Empire Code to the Resonance Region (open access)

Extension of the Empire Code to the Resonance Region

The preliminary version of a new module has been developed to be added to a nuclear reaction model code EMPIRE to allow for an evaluation of neutron cross sections in a resonance region. It automates most of the evaluation procedures and can be executed within EMPIRE or as a stand-alone program. The module includes a graphic user interface (GUI) and a number of codes and scripts that read individual, as well as average, resonance parameters from the Atlas of Neutron Resonances and other physical constants from RIPL-2, perform an analysis of the available resonances, carry out statistical distributions, and compute cross sections in resolved and unresolved resonance regions which are then compared with experimental data. The module also provides an ENDF-formatted file for a resonance region and various plots allowing for a verification of the procedure. The formatted file can be integrated later into the final ENDF-6 file as generated by the EMPIRE code. However, as a preliminary version, extensive testing and further improvements are needed before this new capability can be incorporated into the production version of EMPIRE.
Date: April 22, 2007
Creator: Cho, Y. S.; Herman, M.; Mughabghab, S. F.; Oblozinsky, P.; Rochman, D. & Lee, Y. O.
System: The UNT Digital Library
NEW ENDF/B-VII.0 LIBRARY (open access)

NEW ENDF/B-VII.0 LIBRARY

We describe the new version of the Evaluated Nuclear Data File, ENDF/B-VII.0, of recommended nuclear data for advanced nuclear science and technology applications. The library, produced by the U.S. Cross Section Evaluation Working Group, was released in December 2006. The library contains data in 14 sublibraries, primarily for reactions with incident neutrons, protons and photons, based on the experimental data and nuclear reaction theory predictions. The neutron reaction sublibrary contains data for 393 materials. The new library was extensively tested and shows considerable improvements over the earlier ENDF/B-VI.8 library.
Date: April 22, 2007
Creator: OBLOZINSKY,P.
System: The UNT Digital Library