Measurements of astrophysical neutron capture cross sections via the inverse reaction

Abstract

Neutron capture of short-lived isotopes can be important within several astrophysical environments. The laboratory investigation of these reactions can be difficult since these isotopes cannot form a target. We used radioactive beams and measured the inverse reaction instead. Particularly we used (15)C and (9)Li beams to measure the (14)C(n,gamma)(15)C, and (8)Li(n, gamma)(9)Li reactions. We determined the reaction rates within the astrophysically interesting temperature range. Our data for the (14)C capture rises quickly up to 8mub and then it decreases by a factor of two at 1 MeV. We investigated neutron capture by 8 Li which is one possible leak of the bridging reaction (8)Li(alpha, n)(11)B of the A=8 gap. We found that this leak is lower than the theoretical expectations.