Speaker
Description
In core He burning and C-shell burning of massive stars, the 22Ne(α,n)25Mg reaction is considered to be a dominant neutron source for the weak s process. The reaction also largely contributes to the neutron production for the main s process in asymptotic giant branch (AGB) stars. While a variety of experimental attempts to determine the rate for this reaction at the Gamow window corresponding to s process temperatures have been made either through direct or indirect measurements, uncertainties of some resonance strengths in 26Mg, particularly about two resonances (Ex ~ 11.17 and 11.32 MeV) above neutron separation energy (Sn =11.09 MeV), have remained a long-standing problem. To address this problem, we performed an experiment using the 6Li(22Ne,26Mg)d α-transfer reaction in inverse kinematics at K150 cyclotron of Texas A&M University. A 6LiF target was bombarded with a 7 MeV/u 22Ne beam. Deuterons, γ-rays, and recoil Mg ions were detected in coincidence using a large Si detector array (TIARA), HPGe clover detectors, and an MDM spectrometer backed by an ionization chamber, respectively, to precisely obtain the 26Mg excitation spectrum. Results about the resonances obtained from the experiment will be presented.
