Speaker
Jens Hasper
(Institut fuer Kernphysik, Universitaet zu Koeln, 50937 Koeln, Germany)
Description
The p-process is the most promising astrophysical scenario for the nucleosynthesis of about
35 proton-rich nuclei referred to as p nuclei. This process involves an extensive reaction network
of about 2000 nuclei and more than 20000 reactions, especially photodisintegration reactions,
under explosive physical conditions. The huge number of reaction rates are mainly adopted
from Hauser-Feshbach calculations. Hence, experimental data are essential to put stringent
constraints on the nuclear models required for these calculations. It is the major aim of ex-
perimental p-process studies to improve descriptions for optical model potentials, nuclear level
densities and photon strength functions.
Experiments on (p,gamma) and (alpha,gamma) reactions are a dedicated approach to study these nuclear
properties at astrophysically relevant energies and, thus, a large number of these experiments
have been performed in the last years. Despite these efforts, the data base is still not sufficient
to derive reliable global nuclear models for reaction-rate calculations, and additional data have
to be provided.
In this contribution, we will give an overview of different experimental methods that have
been applied so far to study proton- and alpha-induced capture reactions. The advantages and
limitations of both the activation and in-beam technique will be discussed. In this context, we
will present the gamma-detector array HORUS at the ion TANDEM accelerator of the University of
Cologne, which allows to perform highly-sensitive in-beam experiments on reactions of astro-
physical interest. An outlook will be given on the unique experimental opportunities for future
p-process studies that are provided by this sophisticated facility.
This project is supported by the DFG under contract ZI 510/5-1.
Author
Jens Hasper
(Institut fuer Kernphysik, Universitaet zu Koeln, 50937 Koeln, Germany)
Co-authors
A. Zilges
(Institut fuer Kernphysik, Universitaet zu Koeln, 50937 Koeln, Germany)
J. Endres
(Institut fuer Kernphysik, Universitaet zu Koeln, 50937 Koeln, Germany)
M. Buessing
(Institut fuer Kernphysik, Universitaet zu Koeln, 50937 Koeln, Germany)
M. Elvers
(Institut fuer Kernphysik, Universitaet zu Koeln, 50937 Koeln, Germany)