Probing explosive nucleosynthesis via direct nuclear reactions

Detailed information about the heavy, neutron-rich nuclei involved in the r-process are needed in order to pin down the origin of heavy elements in the universe.

We have designed an innovative new silicon detector, surrounding an extended gas target, optimized for studies of r-process nuclei. The new $750k TI-STAR silicon tracker detector, under development in an international collaboration at the University of Guelph and TRIUMF, will allow measurements of neutron capture rates in the key A=130 mass region around Sn-132, of pivotal importance for our understanding of r-process nucleosynthesis. TI-STAR also allows unique insight into fission properties of neutron-rich nuclei, important for our understanding of fission re-cycling in the r-process. We present results from S1855 at TRIUMF, targeting resonances with importance for the determination of the neutron flux in explosive nucleosynthesis, to demonstrate the potential of such studies. We also discuss the possibility to couple TI-STAR to GRETINA at FRIB.