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The Aims and Activities of the International Network of Nuclear Structure and Decay Data Evaluators. (open access)

The Aims and Activities of the International Network of Nuclear Structure and Decay Data Evaluators.

International Network of Nuclear Structure and Decay Data (NSDD) Evaluators consists of a number of evaluation groups and data service centers in several countries that appreciate the merits of working together to maintain and ensure the quality and comprehensive content of the ENSDF database (Evaluated Nuclear Structure Data File). Biennial meetings of the network are held under the auspices of the International Atomic Energy Agency (IAEA) to assign evaluation responsibilities, monitor progress, discuss improvements and emerging difficulties, and agree on actions to be undertaken by individual members. The evaluated data and bibliographic details are made available to users via various media, such as the journals ''Nuclear Physics A'' and ''Nuclear Data Sheets'', the World Wide Web, on CD-ROM, wall charts of the nuclides and ''Nuclear Wallet Cards''. While the ENSDF master database is maintained by the US National Nuclear Data Center at the Brookhaven National Laboratory, these data are also available from other nuclear data centers including the IAEA Nuclear Data Section. The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy, in cooperation with the IAEA, organizes workshops on NSDD at regular intervals. The primary aims of these particular workshops are to provide hands-on training in the data …
Date: April 22, 2007
Creator: Nichols, A. L. & Tuli, J. K.
Object Type: Article
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 108, No. 332, Ed. 1 Sunday, April 22, 2007 (open access)

The Altus Times (Altus, Okla.), Vol. 108, No. 332, Ed. 1 Sunday, April 22, 2007

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: April 22, 2007
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
THE ART OF COLLECTING EXPERIMENTAL DATA INTERNATIONALLY: EXFOR, CINDA AND THE NRDC NETWORK. (open access)

THE ART OF COLLECTING EXPERIMENTAL DATA INTERNATIONALLY: EXFOR, CINDA AND THE NRDC NETWORK.

The world-wide network of nuclear reaction data centers (NRDC) has, for about 40 years, provided data services to the scientific community. This network covers all types of nuclear reaction data, including neutron-induced, charged-particle-induced, and photonuclear data, used in a wide range of applications, such as fission reactors, accelerator driven systems, fusion facilities, nuclear medicine, materials analysis, environmental monitoring, and basic research. The now 13 nuclear data centers included in the NRDC are dividing the efforts of compilation and distribution for particular types of reactions and/or geographic regions all over the world. A central activity of the network is the collection and compilation of experimental nuclear reaction data and the related bibliographic information in the EXFOR and CINDA databases. Many of the individual data centers also distribute other types of nuclear data information, including evaluated data libraries, nuclear structure and decay data, and nuclear data reports. The network today ensures the world-wide transfer of information and coordinated evolution of an important source of nuclear data for current and future nuclear applications.
Date: April 22, 2007
Creator: Henriksson, H.; Schwerer, O.; Rochman, D.; Mikhaylyukova, M. V. & Otuka, N.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 146, Ed. 1 Sunday, April 22, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 146, Ed. 1 Sunday, April 22, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: April 22, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
DEFORMATION DEPENDENT TUL MULTI-STEP DIRECT MODEL (open access)

DEFORMATION DEPENDENT TUL MULTI-STEP DIRECT MODEL

The Multi-Step Direct (MSD) module TRISTAN in the nuclear reaction code EMPIRE has been extended in order to account for nuclear deformation. The new formalism was tested in calculations of neutron emission spectra emitted from the {sup 232}Th(n,xn) reaction. These calculations include vibration-rotational Coupled Channels (CC) for the inelastic scattering to low-lying collective levels, ''deformed'' MSD with quadrupole deformation for inelastic scattering to the continuum, Multi-Step Compound (MSC) and Hauser-Feshbach with advanced treatment of the fission channel. Prompt fission neutrons were also calculated. The comparison with experimental data shows clear improvement over the ''spherical'' MSD calculations and JEFF-3.1 and JENDL-3.3 evaluations.
Date: April 22, 2007
Creator: WIENKE,H.; CAPOTE, R.; HERMAN, M. & SIN, M.
Object Type: Article
System: The UNT Digital Library
Empire Ultimate Expansion: Resonances and Covariances. (open access)

Empire Ultimate Expansion: Resonances and Covariances.

The EMPIRE code system is being extended to cover the resolved and unresolved resonance region employing proven methodology used for the production of new evaluations in the recent Atlas of Neutron Resonances. Another directions of Empire expansion are uncertainties and correlations among them. These include covariances for cross sections as well as for model parameters. In this presentation we concentrate on the KALMAN method that has been applied in EMPIRE to the fast neutron range as well as to the resonance region. We also summarize role of the EMPIRE code in the ENDF/B-VII.0 development. Finally, large scale calculations and their impact on nuclear model parameters are discussed along with the exciting perspectives offered by the parallel supercomputing.
Date: April 22, 2007
Creator: Herman, M.; Mughabghab, S. F.; Oblozinsky, P.; Rochman, D.; Pigni, M. T.; Kawano, T. et al.
Object Type: Article
System: The UNT Digital Library

Ensemble: 2007-04-22 – Center for Chamber Music Studies

Access: Use of this item is restricted to the UNT Community
Chamber music concert presented at the UNT College of Music Winspear Hall.
Date: April 22, 2007
Creator: University of North Texas. Center for Chamber Music Studies.
Object Type: Sound
System: The UNT Digital Library

Ensemble: 2007-04-22 – Opera

Opera concert performed at the UNT College of Music Lyric Theater.
Date: April 22, 2007
Creator: University of North Texas. Division of Vocal Studies. Opera.
Object Type: Sound
System: The UNT Digital Library
EVALUATION OF TUNGSTEN ISOTOPES IN THE FAST NEUTRON RANGE INCLUDING CROSS-SECTION COVARIANCE ESTIMATION. (open access)

EVALUATION OF TUNGSTEN ISOTOPES IN THE FAST NEUTRON RANGE INCLUDING CROSS-SECTION COVARIANCE ESTIMATION.

New evaluations for the tungsten isotopes {sup 180,182,183,184,186}W in the neutron energy range up to 60 MeV were produced. In the resonance range only minor adjustments to the resonance parameters were made due to a lack of adequate experimental data. Evaluations in the fast energy region were based on nuclear model calculations using the EMPIRE-2.19 code. Recently derived dispersive coupled-channel optical model potentials for W and Ta isotopes were instrumental to achieve a very good description of the available microscopic cross-section database. Model covariance data were generated with the Monte Carlo technique to produce a prior estimate for the covariance matrix. Experimental data were introduced through the GANDR system. The evaluated files were tested on selected fusion neutronics benchmarks and showed marked improvement compared to other existing evaluations.
Date: April 22, 2007
Creator: CAPOTE,R.; SIN, M.; TRKOV, A.; HERMAN, M.; CARLSON, B.V. & OBLOZINSKY, P.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, April 22, 2007 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, April 22, 2007

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: April 22, 2007
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
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.
Object Type: Article
System: The UNT Digital Library
EXTENSION OF THE NUCLEAR REACTION MODEL CODE EMPIRE TO ACTINIDES NUCLEAR DATA EVALUATION. (open access)

EXTENSION OF THE NUCLEAR REACTION MODEL CODE EMPIRE TO ACTINIDES NUCLEAR DATA EVALUATION.

Recent extensions and improvements of the EMPIRE code system are outlined. They add new capabilities to the code, such as prompt fission neutron spectra calculations using Hauser-Feshbach plus pre-equilibrium pre-fission spectra, cross section covariance matrix calculations by Monte Carlo method, fitting of optical model parameters, extended set of optical model potentials including new dispersive coupled channel potentials, parity-dependent level densities and transmission through numerically defined fission barriers. These features, along with improved and validated ENDF formatting, exclusive/inclusive spectra, and recoils make the current EMPIRE release a complete and well validated tool for evaluation of nuclear data at incident energies above the resonance region. The current EMPIRE release has been used in evaluations of neutron induced reaction files for {sup 232}Th and {sup 231,233}Pa nuclei in the fast neutron region at IAEA. Triple-humped fission barriers and exclusive pre-fission neutron spectra were considered for the fission data evaluation. Total, fission, capture and neutron emission cross section, average resonance parameters and angular distributions of neutron scattering are in excellent agreement with the available experimental data.
Date: April 22, 2007
Creator: CAPOTE,R.; SIN, M.; TRKOV, A.; HERMAN, M.; CARLSON, B.V. & OBLOZINSKY, P.
Object Type: Article
System: The UNT Digital Library
A High Accuracy Method for Semi-supervised Information Extraction (open access)

A High Accuracy Method for Semi-supervised Information Extraction

Customization to specific domains of dis-course and/or user requirements is one of the greatest challenges for today’s Information Extraction (IE) systems. While demonstrably effective, both rule-based and supervised machine learning approaches to IE customization pose too high a burden on the user. Semi-supervised learning approaches may in principle offer a more resource effective solution but are still insufficiently accurate to grant realistic application. We demonstrate that this limitation can be overcome by integrating fully-supervised learning techniques within a semi-supervised IE approach, without increasing resource requirements.
Date: April 22, 2007
Creator: Tratz, Stephen C. & Sanfilippo, Antonio P.
Object Type: Article
System: The UNT Digital Library
Internal Conversion Coefficients - How Good Are They Now? (open access)

Internal Conversion Coefficients - How Good Are They Now?

Internal conversion coefficients involving atomic electrons (ICC) and electron-positron pairs (IPC) are often required to determine transition multipolarities and total transition rates. A new internal conversion coefficient data base, BrIcc has been developed which integrates a number of tabulations on ICC and IPC, as well as {Omega}(E0) electronic factors. To decide which theoretical internal conversion coefficient table to use, the accurately determined experimental {alpha}{sub K}, {alpha}{sub L}, {alpha}{sub Total} and {alpha}{sub K}/{alpha}{sub L} values were compared with the new Dirac-Fock calculations using extreme assumptions on the effect of the atomic vacancy. While the overall difference between experiment and theory is less than 1%, our analysis shows preference towards the so called ''Frozen Orbital'' approximation, which takes into account the effect of the atomic vacancy.
Date: April 22, 2007
Creator: Kibedi, T.; Burrows, T. W.; Trzhaskovskaya, M. B.; Nestor, C. W. Jr. & Davidson, P. M.
Object Type: Article
System: The UNT Digital Library
New Endf/B-Vii.0 Evaluations of Neutron Cross Sections for 32 Fission Products. (open access)

New Endf/B-Vii.0 Evaluations of Neutron Cross Sections for 32 Fission Products.

Neutron cross sections for fission products play important role not only in the design of extended burnup core and fast reactors, but also in the study of the backend fuel cycle and the criticality analysis of spent fuel. New evaluations in both the resonance and fast neutron regions were performed by the KAERI-BNL collaboration for 32 fission products. These were {sup 95}Mo, {sup 101}Ru, {sup 103}Rh, {sup 105}Pd, {sup 109}Ag, {sup 131}Xe, {sup 133}Cs, {sup 141}Pr, and complete isotope chains of {sup 142-148,150}Nd, {sup 144,147,148-154}Sm, and {sup 156,158,160-164}Dy. The evaluations cover a large amount of reaction channels, including all those needed for neutronics calculations. Also, they cover the entire energy range, from 10{sup -5} eV to 20 MeV, including the thermal, resolved, and unresolved resonance regions, and the fast neutron region.
Date: April 22, 2007
Creator: Kim, H.; Lee, Y. O.; Herman, M.; Mughabghab, S. F.; Oblozinsky, P. & Rochman, D.
Object Type: Article
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.
Object Type: Article
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.
Object Type: Article
System: The UNT Digital Library
NUCLEAR DATA NEEDS FOR ADVANCED REACTOR SYSTEMS. A NEA NUCLEAR SCIENCE COMMITTEE INITIATIVE. (open access)

NUCLEAR DATA NEEDS FOR ADVANCED REACTOR SYSTEMS. A NEA NUCLEAR SCIENCE COMMITTEE INITIATIVE.

The Working Party on Evaluation Cooperation (WPEC) of the OECD Nuclear Energy Agency Nuclear Science Committee has established an International Subgroup to perform an activity in order to develop a systematic approach to define data needs for Gen-IV and, in general, for advanced reactor systems. A methodology, based on sensitivity analysis has been agreed and representative core configurations for Sodium, Gas and Lead cooled Fast Reactors (SFR, GFR, LFR) have been defined as well as a high burn-up VHTR and a high burn-up PWR. In the case of SFRs, both a TRU burner (called in fact SFR) and a core configuration with homogeneous recycling of not separated TRU (called EFR) have been considered.
Date: April 22, 2007
Creator: SALVATORES,J.M.; ALIBERTI, G.; PALMIOTTI, G.; ROCHMAN, D.; OBLOZINSKY, P.; HERMANN, M. et al.
Object Type: Article
System: The UNT Digital Library
The Panola Watchman (Carthage, Tex.), Vol. 135, No. 30, Ed. 1 Sunday, April 22, 2007 (open access)

The Panola Watchman (Carthage, Tex.), Vol. 135, No. 30, Ed. 1 Sunday, April 22, 2007

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.
Date: April 22, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Polk County Enterprise (Livingston, Tex.), Vol. 125, No. 32, Ed. 1 Sunday, April 22, 2007 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 125, No. 32, Ed. 1 Sunday, April 22, 2007

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: April 22, 2007
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 139, Ed. 1 Sunday, April 22, 2007 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 139, Ed. 1 Sunday, April 22, 2007

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: April 22, 2007
Creator: Mattox, Jami
Object Type: Newspaper
System: The Gateway to Oklahoma History

Senior Recital: 2007-04-22 - Russel Kitchen, viola

Access: Use of this item is restricted to the UNT Community
A senior recital presented at the UNT College of Music Concert Hall in partial fulfillment of the Bachelor of Music (BM) degree
Date: April 22, 2007
Creator: Kitchen, Russel
Object Type: Sound
System: The UNT Digital Library
Technical Report: Contaminant Organic Complexes: Their structure and energetics in surface decontamination (open access)

Technical Report: Contaminant Organic Complexes: Their structure and energetics in surface decontamination

The Department of Energy has a goal of decontaminating an estimated 180,000 metric tons of metal wastes in various surplus facilities. Uranium (U) and other radioactive actinides and lanthanides are embedded within the mixed oxide structures of the passivity layers of corroded iron and steel. These toxic metals can be dissolved out of the surface layers by a naturally occurring bacterial siderophore called Desferrioxamine B (DFB). DFB is a trihydroxamate ligand with one amine (pK1 =10.89) and three hydroxamate groups (pK2 =9.70, pK3 =9.03, and pK4 =8.30), which chelates with metals through hydroxamate coordination. Complexation of DFB with U can be utilized in decontamination strategy of the passivity layers. Therefore, we have been studying reactions of uranyl U(VI) with zerovalent iron (Fe0) followed by dissolution by DFB. The objectives were to determine the structure and speciation of solution and solid phases of U and to assess the effectiveness of DFB in U dissolution.
Date: April 22, 2007
Creator: Traina, Samuel J. & Sharma, Shankar
Object Type: Report
System: The UNT Digital Library