Mass Measurements of Neutron-rich Nuclei Influential to r-Process Abundances

Sabrina Strauss, University of Notre Dame

The synthesis of heavy elements (Z > 26) cannot proceed through fusion in stars due to energy consumption. Above Z > 26, neutron processes both rapid (r-) and slow (s-) are responsible for the creation of heavy elements. The r-process takes place far away from stability with a series of successive neutron captures and beta decays. The abundances of the resulting heavy elements from the r-process are dependent on nuclear masses, half-lives, and neutron capture rates.

Using several different mass model programs, influential isotopes with poorly known nuclear masses were identified[1] in a recent publication. We have used this study to propose a set of measurements at Argonne National Laboratory using the Canadian Penning Trap (CPT). Several of these nuclei (23) are produced in fission at a rate of 10^-5 for every 100 Californium nuclei, pushing the limits of what is currently experimentally possible. The detector and analysis techniques used at the CPT will be presented.

[1]Brett et al., Eur. Phys. Jour. A, 12184-4 (2012).

Abstract Author(s): S.Y. Strauss, N. Paul, A. Nystrom, K. Seigl, S.T. Marley, M. Mumpower, R. Surman, and A. Aprahamian, ND; J.A. Clark, G. Savard, S. Caldwell, A. Perez Galvan, J. Van Schelt, and M. Sternberg, ANL; K. Sharma and G. Morgan, Manitoba; F. Buchinger and R. Orford, McGill; J. Fallis, TRIUMF