Steven M. Grimes (Ohio University)

Spectroscopy of Levels in 18Ne and 26Si Relevant to Nuclear Astrophysics

Calculations of break-out from the CNO cycle are dependent on the rate of the 17F(p, gamma) reaction. A state of 3+ spin and parity in the appropriate energy range has been sought with conflicting results. Our measurements are of the neutron spectrum for oxygen 16 bombarded by helium 3. Our results support one of the two conflicting energies for the state in question. Very similar questions have been raised about a possible 3+ state in 26 Si. Our measurements of the 24Mg(3He,n) reaction also provide additional information for calculating proton capture on 25Al.