U.S.-Czech Research on Direct Reaction Rates for Nuclear Astrophysics

Texas A&M University, College Station TX

Investigators

Abstract

INT 9909787 Tribble This U.S.-Czech project between Robert Tribble of the Texas A&M Cyclotron Institute and Vaclav Burjan and Vaclav Kroha of the Nuclear Physics Institute of the Academy of Sciences, Czech Republic, features application of an indirect technique to determine direct resonance capture rates for reactions with radioactive nuclei. Their technique for determining astrophysical S-factors works well for systems where the binding energy of the captured particle is small. A capture cross section is determined by the normalization constant that connects the Coulomb shape of the overlap integral outside the nuclear radius to the nuclear interior. Peripheral nuclear transfer reactions are then used to measure this normalization constant. This new technique will be used by the US-Czech research team to determine the direct capture contribution for a number of capture reactions that are important in the hydrogen-burning phase of stellar evolution. If successful, the technique may prove useful in interpreting available solar neutrino data, which in turn could provide new insights applicable to weak-interaction physics. This project in nuclear astrophysics fulfills the program objective of advancing scientific knowledge by enabling experts in the United States and Central Europe to combine complementary talents and share research resources in areas of strong mutual interest and competence. Partial funding for this project was provided by the Stellar Astronomy and Astrophysics Program of the NSF Division of Astronomical Sciences.