Measurement of the $\beta$-branch of $^{12}$B to the Hoyle state in $^{12}$C
ORAL
Abstract
Recent measurements of the $\beta$-branch of $^{12}$B to the Hoyle state give 0.58(2)\%, in contradiction with the value found in the literature of 1.2(3)\%. The precise branching ratio to the Hoyle state is important for understanding the R-Matrix fits of excitation energies in $^{12}$C between 9-13 MeV from studies of $\beta$-delayed triple-alpha decay. Accurate fits to the data are crucial in order to fully disentangle the different states of natural spin and parity in the region. In order to obtain an independent measurement of the $\beta$-branch, we have measured the $\gamma$-branch of the Hoyle state (a cascade going through the 4.44 MeV 2$^+$ state) using the Gammasphere array at ATLAS. The measured value of the $\beta$-branch as well as the implications of the results will be presented.
*Supported by the U.S. DOE ONP DE-AC02-06CH11357
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