Mass measurements in the vicinity of the r p-process and the nu p-process paths with the Penning trap facilities JYFLTRAP and SHIPTRAP

Abstract

The masses of very neutron-deficient nuclides close to the astrophysical r p- and nu p-process paths have been determined with the Penning trap facilities JYFLTRAP at JYFL/Jyvaskyla and SHIPTRAP at GSI/Darmstadt. Isotopes from yttrium (Z=39) to palladium (Z=46) have been produced in heavy-ion fusion-evaporation reactions. In total, 21 nuclides were studied, and almost half of the mass values were experimentally determined for the first time: (88)Tc, (90-92)Ru, (92-94)Rh, and (94,95)Pd. For the (95)Pd(m), (21/2(+)) high-spin state, a first direct mass determination was performed. Relative mass uncertainties of typically delta m/m=5x10(-8) were obtained. The impact of the new mass values has been studied in nu p-process nucleosynthesis calculations. The resulting reaction flow and the final abundances are compared with those obtained with the data of the Atomic Mass Evaluation 2003.