Recent mass measurements for the r process at JYFLTRAP

Abstract

This contribution gives an overview of recent mass measurements performed in the 132 Sn region relevant for the r-process studies. The atomic masses of 121−128 Cd, 129,131 In, 130−135 Sn, 131−136 Sb, and 132−140 Te have been measured with the JYFLTRAP double Penning trap mass spectrometer. Among these, the masses of four r-process nuclei-135 Sn, 136 Sb, 139 Te, and 140 Tehave been experimentally determined for the first time. In addition, the masses of the (11/2 −) isomers in 121,123,125 Cd and 133 Te, (1/2 −) isomers in 129,131 In, and (7 −) isomers in 130 Sn and 134 Sb have been measured and corresponding excitation energies have been determined. The groundstate mass values have been compared to recent Atomic Mass Evaluations and deviations have been found in particular for the states based on beta-decay energies.

Self-consistent description of deformed nuclei at the proton drip line

“…In fact, the path of the rapid proton capture reactions for the production of nuclei, can involve nuclei at the proton drip-line [4], but the reaction rates will depend strongly on details of the structure of nuclei along the path, and in particular, on the knowledge of resonances, since it is mainly dominated by resonant proton capture. Penning traps, have also allowed to isolate isomeric states, and to determine high precision mass measurements [5][6][7], that lead to a clear definition of proton separation energies, which are very import to establish the drip lines and for astrophysical calculations of the abundances.…”