This paper presents the NUBASE2012 evaluation that contains the recommended values for nuclear and decay properties of nuclides in their ground and excited isomeric (T 1/2 ≥100 ns) states. All nuclides for which some experimental information is known are considered. NUBASE2012 covers all up to date experimental data published in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. During the development of NUBASE2012, the data available in the "Evaluated Nuclear Structure Data File" (ENSDF) database were consulted, and critically assessed of their validity and completeness. Furthermore, a large amount of new and somewhat older experimental results that were missing in ENSDF were compiled, evaluated and included in NUBASE2012. The atomic mass values were taken from the "Atomic Mass Evaluation" (AME2012, second and third parts of the present issue). In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclei (TNN) were examined. This approach allowed to estimate, whenever possible, values for a range of properties, and are labeled in NUBASE2012 as "non-experimental" (flagged "#"). Evaluation procedures and policies that were used during the development of this database are presented, together with a detailed table of recommended values and their uncertainties. AMDC: http://amdc.in2p3.fr/ and http://amdc.impcas.ac.cn/ * This work has been undertaken with the encouragement of the IUPAP Commission on Symbols, Units, Nomenclature, Atomic Masses and Fundamental Constants (SUNAMCO).

Based on 106×10(6)ψ(3686) events collected with the BESIII detector at the BEPCII facility, a partial wave analysis of ψ(3686)→ppπ0 is performed. The branching fraction of this channel has been determined to be B(ψ(3686)→ppπ0)=(1.65±0.03±0.15)×10(-4). In this decay, 7 N* intermediate resonances are observed. Among these, two new resonances, N(2300) and N(2570) are significant, one 1/2+ resonance with a mass of 2300(-30-0)(+40+109)  MeV/c2 and width of 340(-30-58)(+30+110)  MeV/c2, and one 5/2- resonance with a mass of 2570(-10-10)(+19+34)  MeV/c2 and width of 250(-24-21)(+14+69)  MeV/c2. For the remaining 5 N* intermediate resonances [N(1440), N(1520), N(1535), N(1650) and N(1720)], the analysis yields mass and width values that are consistent with those from established resonances.

α decay is a common and important process for natural radioactivity of heavy and superheavy nuclei. The α decay half-lives for even-even nuclei from Z=62 to Z=118 are systematically researched based on the two-potential approach with a quasi-stationary state approximation. To describe the deviations between experimental half-lives and calculated results due to the nuclear shell structure, a hindrance factor related with α particle preformation probability is introduced. Our results can well reproduce the experimental data equally to the density-dependent cluster model and the generalized liquid drop model. We also study the isospin effect of nuclear potential in this work. Considering the isospin effect the calculated results improved about 7.3%.

α decay is usually associated with both ground and low-lying isomeric states of heavy and superheavy nuclei, and the unpaired nucleon plays a key role on α decay. In this work, we systematically studied the α decay half-lives of odd-A nuclei, including both favored and unfavored α decay within the two-potential approach based on the isospin dependent nuclear potential. The α preformation probabilities are estimated by using an analytic formula taking into account the shell structure and proton-neutron correlation, and the parameters are obtained through the α decay half-lives data.The results indicate that in general the α preformation probabilities of even-Z, odd-N nuclei are slightly smaller than the odd-Z, even-N ones. We found that the odd-even staggering effect may play a more important role on spontaneous fission than α decay. The calculated half-lives can well reproduce the experimental data.

In this work, we systematically investigate the favored α-decay half-lives and α preformation probabilities of both odd-A and doubly-odd nuclei related to ground and isomeric states around the doubly magic cores at Z = 82, N = 82 and at Z = 82, N = 126, respectively, within a two-potential approach from the view of the valence nucleon (or hole). The results show that the α preformation probability is linear related to NpNn or NpNnI, where Np, Nn, and I are the number of valence protons (or holes), the number of valence neutrons (or holes), and the isospin of the parent nucleus, respectively. Fitting the α preformation probabilities data extracted from the differences between experimental data and calculated half-lives without a shell correction, we give two analytic formulas of the α preformation probabilities and the values of corresponding parameters. Using those formulas and the parameters, we calculate the α-decay half-lives for those nuclei. The calculated results can well reproduce the experimental data.

A new scheme to study the properties of finite nuclei is proposed based on the Dirac-Brueckner-Hartree-Fock (DBHF) approach starting from a bare nucleon-nucleon interaction. The relativistic structure of the nucleon self-energies in nuclear matter depending on density, momentum and isospin asymmetry are determined through a subtracted T-matrix technique and parameterized, which makes them easily accessible for general use. The scalar and vector potentials of a single particle in nuclei are generated via a local density approximation (LDA). The surface effect of finite nuclei can be taken into account by an improved LDA (ILDA), which has successfully been applied in microscopic derivations of the optical model potential for nucleon-nucleus scattering. The bulk properties of nuclei can be determined in a self-consistent scheme for nuclei all over the nuclear mass table. Calculated binding energies agree very well with the empirical data, while the predicted values for radii and spin-orbit splitting of single-particle eneries are about 10 % smaller than the experimental data. Basic features of more sophisticated DBHF calculations for finite nuclei are reproduced.

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