s-process nucleosynthesis-nuclear physics and the classical model

TLDR

The slow neutron capture (s‑process) in stars involves mainly stable isotopes, allowing experimental determination of nuclear data and serving as a testbed for late‑stage stellar evolution models, with the classical phenomenological s‑process used to derive abundances and infer physical conditions. The paper reviews the classical s‑process approach, its implications for stellar models and spectroscopy, and briefly discusses potential s‑process chronometers. The authors review the classical s‑process model, synthesizing recent spectroscopic data and model predictions.

Abstract

Among the various processes responsible for the formation of the heavy elements in stars, the slow neutron capture process (s-process) is distinguished by the fact that it involves mostly stable isotopes. Therefore, the relevant nuclear physics data can be determined by experiments. With this rather reliable data basis, s-process nucleosynthesis offers an important testground of models for the late stages of stellar evolution, which are supposed to be the s-process site. The empirical counterpart for such models is the so-called classical s-process, a purely phenomenological picture, that is successfully used to derive the resulting abundances as well as information on the physical conditions during the s-process. The status of this classical approach is reviewed with emphasis on the implications for various stellar models of the s-process and in the light of results obtained by stellar spectroscopy. A brief account of the potential s-process chronometers is also presented.