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At least 685 records · Page 38
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Nuclear Data Sheets for A = 60

The 2003 evaluation of A = 60 (2003Tu08) has been revised and brought up-to-date with references received by the cutoff date noted below.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2015

Nuclear Data Sheets for A = 61

The evaluated spectroscopic data are presented for known nuclides of mass 61 (Sc,Ti,V,Cr,Mn,Fe,Co,Ni, Cu,Zn,Ga,Ge). Excited-state data are nonexistent for {sup 61}Sc, {sup 61}Ti, {sup 61}V, and {sup 61}Ge. Significant amounts of new data have been added since the previous NDS evaluation of A=61 nuclides (1999Bh04). {sup 61}Sc nuclide is now experimentally known, but without any knowledge of its half-life. The ground state half-lives of {sup 61}Ti and {sup 61}V are now determined. Excited-state data have become available for {sup 61}Cr, {sup 61}Mn and {sup 61}Ga, while for {sup 61}Ge, five excited states were erroneously assigned in the previous evaluation, these have been omitted here. Improved and extensive high-spin excitations are available for {sup 61}Fe, {sup 61}Cu and {sup 61}Zn, including several new superdeformed structures in {sup 61}Cu and {sup 61}Zn. Thermal neutron capture γ-ray data are available in detail from 2004Ra23. The radioactive decay schemes of {sup 61}Sc and {sup 61}Ti are not known, while those for {sup 61}V, {sup 61}Fe and {sup 61}Ge are poorly known. This work benefited from the earlier full evaluations of A=61 published by 1999Bh04, 1983Ek01 and 1975Au05 and the one published in an ‘update’ mode by 1992Zh31. The data and conclusions presented in the current work supersede those in all the previous evaluations.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2015

Nuclear Data Sheets for A = 43

The experimental data are evaluated for known nuclides of mass number A = 43 (Al,Si,P,S,Cl,Ar,K,Ca,Sc,Ti,V,Cr). Detailed evaluated level properties and related information are presented, including adopted values of level and γ–ray energies, decay data (energies, intensities and placement of radiations), and other spectroscopic data. Here, this work supersedes earlier full evaluations of A = 43 published by 2001Ca24 and 1990En08 (also 1978En04, and 1998En04 update).

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2018

Nuclear Data Sheets for A=136☆

Spectroscopic data for all nuclei with mass number A=136 have been evaluated and the corresponding level schemes from radioactive decay and reaction studies are presented. No excited states are known in {sup 136}In, {sup 136}Eu, or {sup 136}Gd and {sup 136}Tb remains unidentified. Discrepancies between experiments on isomeric decays in {sup 136}Sb and {sup 136}La suggest the need for futher experimental investigation. The decay of {sup 136}Eu has only been observed in a mixed source. The energy of the 17.5 s isomer in {sup 136}Cs was determined since the last evaluation, however, the branching ratio remains unknown. This work supersedes the earlier full evaluation of A=136 by A.A. Sonzogni (2002So05), and benefited tremendously from all previous evaluations of A=136.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2012

Nuclear photon scattering and its application to nuclear physics investigation

Electro-magnetic dipole transitions below the neutron separation energy in {sup 56}Fe have been measured by using a quasi-monochromatic, linearly polarized photon beam generated by the Compton scattering of laser light with high energy electrons. The parity of the resonant states in {sup 56}Fe was determined by the intensity asymmetry of resonant scattering {gamma} rays relative to the polarization plane of the incident photon beam. The total magnetic dipole strength of {approx}6{mu}{sup 2}{sub N} at the excitation energies between 6 and 10 MeV was obtained.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2018

Effects of retarded electrical fields on observables sensitive to the high-density behavior of the nuclear symmetry energy in heavy-ion collisions at intermediate energies

Within the isospin- and momentum-dependent transport model IBUU11, we examine here the relativistic retardation effects of electrical fields on the π - / π + ratio and neutron-proton differential transverse flow in heavy-ion collisions at intermediate energies. Compared to the static Coulomb fields, the retarded electric fields of fast-moving charges are known to be anisotropic and the associated relativistic corrections can be significant. They are found to increase the number of energetic protons in the participant region at the maximum compression by as much as 25% but that of energetic neutrons by less than 10% in 197 Au + 197 Au reactions at a beam energy of 400 MeV/nucleon. Consequently, more π + and relatively fewer π - mesons are produced, leading to an appreciable reduction of the π - / π + ratio compared to calculations with the static Coulomb fields. Also, the neutron-proton differential transverse flow, as another sensitive probe of high-density symmetry energy, is also decreased appreciably due to the stronger retarded electrical fields in directions perpendicular to the velocities of fast-moving charges compared to calculations using the isotropic static electrical fields. Moreover, the retardation effects on these observables are found to be approximately independent of the reaction impact parameter.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2016

Nanoscale imaging of Li and B in nuclear waste glass, a comparison of ToF-SIMS, NanoSIMS, and APT: Nanoscale imaging of Li and B in nuclear waste glass

It has been very difficult to use popular elemental imaging techniques to image Li and B distribution in glass samples with nanoscale resolution. In this study, atom probe tomography (APT), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and nanoscale secondary ion mass spectrometry (NanoSIMS) were used to image the distribution of Li and B in two representative glass samples. APT can provide three-dimensional Li and B imaging with very high spatial resolution (≤ 2 nm). In addition, absolute quantification of Li and B is possible, though room remains to improve accuracy. However, the major drawbacks of APT include limited field of view (normally ≤ 100 × 100 × 500 nm 3 ) and poor sample compatibility. As a comparison, ToF-SIMS and NanoSIMS are sample-friendly with flexible field of view (up to 500 × 500 μm 2 and image stitching is feasible); however, lateral resolution is limited to only about 100 nm. Therefore, SIMS and APT can be regarded as complementary techniques for nanoscale imaging Li and B in glass and other novel materials.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗