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The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions studies for all isobars with mass number A = 99 . [ABSTRACT FROM AUTHOR]

Spectroscopic data and level schemes from radioactive decay and nuclear reaction studies are presented here for all nuclei with mass number A=239. In general, a relatively small amount of new data on this mass chain has been reported since the previous evaluation in 2003. However, special evaluations, such as “Database of prompt gamma rays from slow neutron–capture from elemental analysis” (2007ChZX), have provided additional precise data for levels in 239 U. Also, new Coulomb excitation measurements in 239 Pu have extended the knowledge of the 1/2[631] rotational band up to J π = ( 55 / 2 + ) , and that of the octupole vibrational band up to J π = ( 53 / 2 − ) . For historical knowledge it is worth mentioning the report on the “Discovery of isotopes of the transuranium elements with 93 <= Z <= 98” (2013Fr02), where the information for elements Np, Pu, Am, and Cf with mass number A=239 is presented. The alpha hindrance factors (HF) presented in this evaluation were calculated using values of the radius parameter (r 0 ) interpolated from those for even–even adjacent nuclei given by 1998Ak04. [ABSTRACT FROM AUTHOR]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions for all isobars with mass number A=230. This evaluation includes the first experimental evidence of 230Am, produced through the 197Au(40Ar,3n)234Bk (α decay to 230Am) reaction, E(40Ar)=188.4 MeV (2003MoZX). [Copyright &y& Elsevier]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reaction studies for all nuclei with mass number A = 143. The evaluation, which includes all data received by May 2011, supersedes the 2001 evaluation by J.K. Tuli, published in Nuclear Data Sheets 94, 605 (2001). [Copyright &y& Elsevier]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reaction studies for all nuclei with mass number A=246. [Copyright &y& Elsevier]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions studies for all isobars with mass number A = 99. [Copyright &y& Elsevier]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions studies for all isobars with mass number A=65. Not much is known experimentally about 65V and 65Cr, although they are expected to decay by β-emission. Spin/parity assignments for 65Mn, 65Fe, 65As, and 65Se are not firmly established. [ABSTRACT FROM AUTHOR]

When 239Pu and 235U undergo thermal neutron-induced fission, both produce significant numbers of beta-delayed gamma rays with energies in the several megaelectron volt range. Experiments using high energy-resolution germanium detectors have shown that it is possible to distinguish the fission of 239Pu from that of 235U. It is desirable to detect the presence of 235U or 239Pu using detectors that are less expensive and more rugged than high purity germanium detectors. To this end we demonstrate how differences in the energy spectrum and decay rates of the beta-delayed gamma rays can be used to identify 239Pu and 235U using low resolution plastic and liquid scintillator detectors. Experimental data are used to identify differences in the spectra and also to test the identification algorithms. Results to date are very promising. [ABSTRACT FROM AUTHOR]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reaction studies for all isobars with mass number A = 119. [Copyright &y& Elsevier]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reaction studies for all nuclei with mass number A = 229. These nuclei belong to a region of coexisting quadrupole with possible octupole deformations. The latter have been observed in 229Ra, but in 229Pa the experimental evidence is inconclusive. The present evaluation of A = 229, which includes all data received by June 2008, supersedes the 1989 evaluation by Y.A. Akovali, published in Nuclear Data Sheets 58, 555 (1989). Highlights of this publication are given below: A comprehensive spectroscopic study of 229Fr(50.2 s) β- decay using mass-separated sources have provided the first evidence of parity doublets in 229Ra due to nuclear octupole deformation (1999Fr33). In 229Th a level at 7.6 5 eV – the closest level to the ground state ever known – has been confirmed through extremely precise measurements of γ-ray energies from 233U α decay (1994He08, 2007Be16). A nuclear level at such low energy may be used for studying a large variety of atomic properties associated to nuclear decay. The level structure in 229Pa has been interpreted in terms of the rotational model (1994Le22). Some authors, however, have proposed the existence of parity doublets as evidence of octupole nuclear deformation (1982Ah08). This interpretation has not been confirmed. [Copyright &y& Elsevier]

Abstract: The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions for all isobars with mass number A = 137. [Copyright &y& Elsevier]

Abstract: Of significant interest in the field of relaxation mechanisms in polymer systems is the possible existence of a spatial heterogeneity existing in an otherwise single phase homogenous polymer material. Here, frequency dependent dielectric and mechanical measurements along with DSC measurements show that as early as 5% conversion during cure of a styrene–dimethacrylate systems, two distinctly different α-relaxation regions exist along with two T g is in the DSC spectra. The heterogeneity persists as the cure advances. The breadth of each relaxation increases and results in an extremely broad relaxation spectrum and T g transition near cure completion. This result also provides an additional example demonstrating that the existence of two T g is does not by itself indicate phase separation. [Copyright &y& Elsevier]

The evaluator presents in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions studies for all nuclei with mass numbers A=235,239.A relatively small amount of new data on the level structure of nuclei with A=235,239 has been reported since the previous evaluation of this mass chain. The data presented here are mostly that from 1993Sc22 and 1992Sc18 but updated and modified as needed.A new isotope of americium, 235Am (9.9 min), which was chemically and mass separated, was identified using a He-jet recoil transport technique (1996Gu11,1997Sh21,1999Ya13), and has been included in this evaluation.A new isotope of protactinium, 239Pa (1.8 hr.) has been included in this evaluation. This nuclide was produced by bombarding uranium with 18O projectiles; it was chemically separated and its genetic relationship to its daughter nuclide 239U was well established (1995Yu01,1996Yu06).The alpha hindrance factors (HF) presented in this evaluation were calculated using values of the radius parameter (r0) interpolated from those for even-even adjacent nuclei given by 1998Ak04. [Copyright &y& Elsevier]

α decay of 249Bk has been investigated by measuring its α and γ-ray spectra, both in singles and in coincidence modes. The α spectrum of a freshly purified 249Bk sample was measured with a high-resolution, double-focusing magnetic spectrometer, γ singles, γ-γ coincidence, and γ-α coincidence spectra were also recorded. The absolute intensity of the 327.45-keV γ ray has been determined to be ( 1.44 ± 0.08) × 10-5 % per 249Bk decay. Assignments of previously known single-particle states were confirmed. A new rotational band was identified in the a singles spectrum and Am K x rays have been observed in its decay. This single-particle state, with an energy of 154 keV, has been assigned to the 3/2--[521] Nilsson state. This is the lowest excitation energy for this orbital in any Am nucleus. More precise energies and intensities of the 249Bk α groups and γ-ray transitions are provided. [ABSTRACT FROM AUTHOR]

Abstract: The beta-delayed gamma-ray spectra from the fission of 235U, 238U, and 239Pu by thermal and near-14-MeV neutrons have been measured for delay times ranging from 1min to 14h. Spectra at all delay times contain sets of prominent gamma-ray lines with intensity ratios that identify the fissile material and distinguish between fission induced by low-energy or high-energy neutrons. [Copyright &y& Elsevier]