Dr. Ronald Schwengner
Nuclear Physics Division
Institute of Radiation Physics
Bautzner Landstraße 400
Tel.: +49 351 260 3332
Fax: +49 351 260 13332
Gamma-ray strength in nuclear physics and nuclear technology
- Gamma-ray strength functions describe average electromagnetic transition strengths in the quasicontinuum of nuclear states at high excitation energy and level density. These strength functions are an important input quantity for calculations of reaction rates of photonuclear reactions as well as of the inverse radiative-capture reactions in codes based on the statistical reaction theory. For example, modifications of the strength functions can cause drastic changes of the abundances of elements produced via neutron capture in the so-called r-process occurring in violent stellar events.
- An improved experimental as well as theoretical knowledge of electromagnetic strength functions is needed for the correct description of radiative-capture reactions that are important for astrophysical processes as well as for next-generation nuclear technologies, such as the transmutation of long-lived nuclear waste.
- We investigate gamma-ray strength
functions in photon-induced and in neutron-induced nuclear reactions as well as in theoretical studies:
Photon scattering and photoactivation experiments are carried out with bremsstrahlung at the γELBE facility of HZDR and with monoenergetic, polarized photon beams at the HIγS facility of the Triangle Universities Nuclear Laboratory in Durham, North Carolina, USA.
Neutron-capture experiments are performed at the high-flux reactor of the ILL Grenoble and also at the research reactors at IKI Budapest and UJV Rez-Prague.