Nuclei in the Cosmos - IX

Photodisintegration of Ta-181 leading to the isomeric state Ta-180(m)

30 Jun 2006, 10:00

15m

CERN, Geneva

Oral contribution Experiments in nuclear astrophysics 14 Experiments in nuclear astrophysics IV

Speaker

S Goko (Konan University)

Description

Photoneutron cross sections for $^{180}$Ta$^{m}$ were determined from simultaneous measurements of total cross sections ($\sigma^{tot}$) and ground-state cross sections ($\sigma^{gs}$) for $^{180}$Ta in photodisintegration of $^{181}$Ta with laser Compton-backscattered $\gamma$ rays. Techniques of direct neutron counting and photoactivation were used for the measurement of $\sigma^{tot}$ and $\sigma^{gs} $, respectively. The partial cross sections for the isomeric state serves as a novel probe of the nuclear level density of $^{180}$Ta. Implications for the p- and s-process nucleosynthesis of $^{180}$Ta$^m$ are given.