Mass measurements in the vicinity of the rp-process and the nu p-process paths with JYFLTRAP and SHIPTRAP

TL;DR

This study measured the masses of 21 neutron-deficient nuclides near the rp- and nu p-process paths using Penning traps, providing new data that impacts astrophysical nucleosynthesis models.

Contribution

First direct mass measurements of several isotopes near the rp- and nu p-process paths, including many for the first time, with high precision using JYFLTRAP and SHIPTRAP.

Findings

Almost half of the mass values were determined for the first time.

High-precision mass measurements with uncertainties around 5×10^{-8}.

Mass data significantly influence nucleosynthesis reaction flow and abundance predictions.

Abstract

The masses of very neutron-deficient nuclides close to the astrophysical rp- and nu p-process paths have been determined with the Penning trap facilities JYFLTRAP at JYFL/Jyv\"askyl\"a 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: 88Tc, 90-92Ru, 92-94Rh, and 94,95Pd. For the 95Pdm, (21/2^+) high-spin state, a first direct mass determination was performed. Relative mass uncertainties of typically $\delta m / m = 5 \times 10^{-8}$ 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 to those obtained with the data of the Atomic Mass Evaluation 2003.