We tabulate the atomic mass excesses and nuclear ground-state deformations of 8979 nuclei ranging from 16 O to A = 339. The calculations are based on the finite-range droplet macroscopic model and the folded-Yukawa single-particle microscopic model. Relative to our 1981 mass table the current results are obtained with an improved macroscopic model, an improved pairing model with a new form for the effective-interaction pairing gap, and minimization of the ground-state energy with respect to additional shape degrees of freedom. The values of only 9 constants are determined directly from a least-squares adjustment to the ground-state masses of 1654 nuclei ranging from 16 O to 263 106 and to 28 fission-barrier heights. The error of the mass model is 0.669 MeV for the entire region of nuclei considered, but is only 0.448 MeV for the region above N = 65.

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We describe the next generation general purpose Evaluated Nuclear Data File, ENDF/B-VII.0, of recommended nuclear data for advanced nuclear science and technology applications. The library, released by the U.S. Cross Section Evaluation Working Group (CSEWG) in December 2006, contains data primarily for reactions with incident neutrons, protons, and photons on almost 400 isotopes. The new evaluations are based on both experimental data and nuclear reaction theory predictions.The principal advances over the previous ENDF/B-VI library are the following: (1) New cross sections for U, Pu, Th, Np and Am actinide isotopes, with improved performance in integral validation criticality and neutron transmission benchmark tests; (2) More precise standard cross sections for neutron reactions on H, 6 Li, 10 B, Au and for 235,238 U fission, developed by a collaboration with the IAEA and the OECD/NEA Working Party on Evaluation Cooperation (WPEC); (3) Improved thermal neutron scattering; (4) An extensive set of neutron cross sections on fission products developed through a WPEC collaboration; (5) A large suite of photonuclear reactions; (6) Extension of many neutron-and proton-induced reactions up to an energy of 150 MeV; (7) Many new light nucleus neutron and proton reactions; (8) Post-fission beta-delayed photon decay spectra; (9) New radioactive decay data; and (10) New methods developed to provide uncertainties and covariances, together with covariance evaluations for some sample cases.The paper provides an overview of this library, consisting of 14 sublibraries in the same, ENDF-6 format, as the earlier ENDF/B-VI library. We describe each of the 14 sublibraries, focusing on neutron reactions. Extensive validation, using radiation transport codes to simulate measured critical assemblies, show major improvements: (a) The long-standing underprediction of low enriched U thermal assemblies is removed; (b) The 238 U, 208 Pb, and 9 Be reflector biases in fast systems are largely removed; (c) ENDF/B-VI.8 good agreement for simulations of highly enriched uranium assemblies is preserved; (d) The underprediction of fast criticality of 233,235 U and 239 Pu assemblies is removed; and (e) The intermediate spectrum critical assemblies are predicted more accurately.We anticipate that the new library will play an important role in nuclear technology applications, including transport simulations supporting national security, nonproliferation, advanced reactor and fuel cycle concepts, criticality safety, medicine, space applications, nuclear astrophysics, and nuclear physics facility design. The ENDF/B-VII.0 library is archived at the National Nuclear Data Center,

Recent compilations of experimental gross ␤-decay properties, i.e., half-lives (T 1/2 ) and neutron-emission probabilities ( P n ), are compared to improved global macroscopic-microscopic model predictions. The model combines calculations within the quasiparticle ͑QP͒ random-phase approximation for the Gamow-Teller ͑GT͒ part with an empirical spreading of the QP strength and the gross theory for the first-forbidden part of ␤ Ϫ decay. Nuclear masses are either taken from the 1995 data compilation of Audi et al., when available, otherwise from the finite-range droplet model. Especially for spherical and neutron-͑sub-͒magic isotopes a considerable improvement compared to our earlier predictions for pure GT decay ͑ADNDT, 1997͒ is observed. T 1/2 and P n values up to the neutron drip line have been used in r-process calculations within the classical ''waiting-point'' approximation. With the new nuclear-physics input, a considerable speeding-up of the r-matter flow is observed, in particular at those r-abundance peaks which are related to magic neutron-shell closures.

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The symmetry energy contribution to the nuclear equation of state impacts various phenomena in nuclear astrophysics, nuclear structure, and nuclear reactions. Its determination is a key objective of contemporary nuclear physics, with consequences for the understanding of dense matter within neutron stars. We examine the results of laboratory experiments that have provided initial constraints on the nuclear symmetry energy and on its density dependence at and somewhat below normal nuclear matter density. Even though some of these constraints have been derived from properties of nuclei while others have been derived from the nuclear response to electroweak and hadronic probes, within experimental uncertainties-they are consistent with each other. We also examine the most frequently used theoretical models that predict the symmetry energy and its slope parameter. By comparing existing constraints on the symmetry pressure to theories, we demonstrate how contributions of three-body forces, which are essential ingredients in neutron matter models, can be determined.

Nuclear potential energy surfo:>,ces a~ a functlcin of cleforma:tions are calculated on the basis of a nt)dified osclll.at.or model. In particular, quadrupole (P 2) and hexadecupole (P 1) deformation;; nrc • considered. The average behavior of the sur_face is norrr:a.lized to that ofu liquid drop through 'the employment of a gei1eraliz.ed Strutinski prescription. In this way a synthesi:; of the slnglc particle model and the liquid drop model is obtained. Lowest minima. in the potential energy surfaces give the ~rounc~ state masses ond distortions. These results compare extremely well wi.th experimental data. Spontaneous fission half lives are obtained. 'l'he inertial parameters as::wcia ted with fission barrier pcnetn:ttlon are derived empidcally as well as by a microscopic modeL Sh::tpe (fisslon) isomeric states _o.re also found. Thelr N and Z dependence in the present model are discusccd and results tabulated. The calculations arc extended to the predicted nuperbea.vy region around Z :: 111~ nnd N == 18/1. 1'he total overall stnh:U.i ty ~rith respect to alpha L-tnd beta. decay, and Epontaneous fission fs fou .. "ld to be most favorable in the vic:!n.Uy of b:::: 110 and N = J.8IL Detailed diagrams and tables arc exhibited.