Determination of Astrophysical Direct Capture Reaction Rate for 26Si(p,γ)27P by Extracting the Asymptotic Normalization Coefficients in the Mirror Nuclear System

Abstract

The ^26Si(p,γ)^27P reaction is of primary interest to this study in connection with its role in the destruction of the important astrophysical observable ^26Al. Due to very limited experimental information, more experimental data are clearly needed in the calculation of the ^26Si(p,γ)^27P reaction rate at the temperature of astrophysical interest. However, the reaction rate information for ^26Si(p,γ)^27P cannot be obtained today with direct measurements. Hence, it was decided to study the ^26Si(p,γ)^27P reaction using the indirect asymptotic normalization coefficient (ANC) technique. In this method, ^26Si(p,γ)^27P can be studied by means of its mirror nuclear systems ^26Mg+n→^27Mg, and the reaction rate for the radioactive proton capture ^26Si(p,γ)^27P at stellar energies can be determined through measurements of the ANC in the mirror nuclear system ^26Mg+n→^27Mg. For this reason, ^13C(^26Mg,^26Mg)^13C and the single neutron transfer channel ^13C(^26Mg,^27Mg)^12C measurements were performed. The extracted neutron asymptotic normalization coefficient for ^27Mg was used to determine the reaction rate for ^26Si(p,γ)^27P. As a part of this dissertation, the elastic scattering of ^28Si and ^32S on ^13C experiments were also performed using the newly upgraded Oxford detector. The extracted optical parameters along with an overview of the upgrade process of the Oxford detector are presented.