The History of Nuclidic Masses and of their Evaluation

This paper is centered on some historical aspects of nuclear masses, and their relations to major discoveries. Besides nuclear reactions and decays, the heart of mass measurements lies in mass spectrometry, the early history of which will be reviewed first. I shall then give a short history of the mass unit which has not always been defined as one twelfth of the carbon-12 mass. When combining inertial masses from mass spectrometry with energy differences obtained in reactions and decays, the conversion factor between the two is essential. The history of the evaluation of the nuclear masses (actually atomic masses) is only slightly younger than that of the mass measurements themselves. In their modern form, mass evaluations can be traced back to 1955. Prior to 1955, several tables were established, the oldest one in 1935.Comment: 17 pages, Contribution to the special issue of the International Journal of Mass Spectrometry (IJMS) in the honor of the 65th anniversary of Jurgen Kluge's birthda

Structure and decay properties of spin-dipole giant resonances within a semimicroscopical approach

A semimicroscopical approach is applied to calculate: (i) strength functions for the charge-exchange spin-dipole giant resonances in the 208Pb parent nucleus; (ii) partial and total branching ratios for the direct proton decay of the resonance in 208Bi. The approach is based on continuum-RPA calculations of corresponding reaction-amplitudes and phenomenological description of the doorway-state coupling to many-quasiparticle configurations. The only adjustable parameter needed for the description is found by comparison of the calculated and experimental total widths of the resonance. Other model parameters used in calculations are taken from independent data. The calculated total branching ratio is found to be in reasonable agreement with the experimental value.Comment: 15 pages, 4 figures, submitted to Phys. Lett.

The AME2003 atomic mass evaluation (I) - Evaluation of input data, adjustment procedures

This paper is the first of two parts presenting the result of a new evaluation of atomic masses (Ame2003). In this first part we give full information on the used and rejected input data and on the procedures used in deriving the tables in the second part. We first describe the philosophy and procedures used in selecting nuclear-reaction, decay, and mass spectrometric results as input values in a least-squares evaluation of best values for atomic masses. The calculation procedures and particularities of the Ame are then described. All accepted data, and rejected ones with a reported precision still of interest, are presented in a table and compared there with the adjusted values. The differences with the earlier evaluation are briefly discussed and information is given of interest for the users of this Ame. The second paper for the Ame2003, last in this issue, gives a table of atomic masses, tables and graphs of derived quantities, and the list of references used in both this evaluation and the Nubase2003 table (first paper in this issue)

The strength of the analog and Gamow-Teller giant resonances and hindrance of the 2\nu\beta\beta -decay rate

An approach for describing the hindrance of the nuclear 2\nu\beta\beta-decay amplitude is proposed. The approach is based on a new formula obtained by a model-independent transformation of the initial expression for the amplitude. This formula takes explicitly into account the hindrance of the decay-amplitude due to the presence of the collective Gamow-Teller state. Calculations are performed within the simplest version of the approach. Calculated and experimental 2\nu\beta\beta halve-lives are compared for a wide range of nuclei.Comment: 11 pages, 1 tabl

The Nuclear Science References (NSR) Database and Web Retrieval System

The Nuclear Science References (NSR) database together with its associated Web interface, is the world's only comprehensive source of easily accessible low- and intermediate-energy nuclear physics bibliographic information for more than 200,000 articles since the beginning of nuclear science. The weekly-updated NSR database provides essential support for nuclear data evaluation, compilation and research activities. The principles of the database and Web application development and maintenance are described. Examples of nuclear structure, reaction and decay applications are specifically included. The complete NSR database is freely available at the websites of the National Nuclear Data Center http://www.nndc.bnl.gov/nsr and the International Atomic Energy Agency http://www-nds.iaea.org/nsr.Comment: 16 pages, 5 figure