Experimental investigation of the 30S(α, p) thermonuclear reaction in x-ray bursts
1 Center for Nuclear Study, Graduate School of Science, the University of Tokyo, Japan
2 Department of Physics & Astronomy, McMaster University, Canada
3 RIKEN Nishina Center, RIKEN (The Institute of Physical and Chemical Research), Japan
4 Institute of Modern Physics, Chinese Academy of Sciences, China
5 Institute of Physics, Vietnam
6 Department of Physics, University of Catania & INFN, Italy
7 Department of Physics, Tohoku University, Japan
8 Department of Physics, Chung-Ang University, Korea
9 Department of Physics, Yamagata University, Japan
10 Department of Physics, Kyushu University, Japan
a e-mail: firstname.lastname@example.org
Published online: 12 February 2016
We performed the first measurement of 30S+α resonant elastic scattering to experimentally examine the 30S(α, p) stellar reaction rate in type I x-ray bursts. These bursts are the most frequent thermonuclear explosions in the galaxy, resulting from thermonuclear runaway on the surface of accreting neutron star binaries. The 30S(α, p) reaction plays a critical role in burst models, yet very little is known about the compound nucleus 34Ar at these energies nor the reaction rate itself. We performed a measurement of alpha elastic scattering with a radioactive beam of 30S to experimentally probe the entrance channel. Utilizing a gaseous active target system and silicon detector array, we extracted the excitation function from 1.8 to 5.5 MeV near 160° in the center-of-mass frame. The experimental data were analyzed with an R-Matrix calculation, and we discovered several new resonances and extracted their quantum properties (resonance energy, width, spin, and parity). Finally, we calculated the narrow resonant thermonuclear reaction rate of 30S(α, p) for these new resonances.
© Owned by the authors, published by EDP Sciences, 2016
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