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Unbound states of 32Cl and the 31S(p,gamma)32Cl reaction rate

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 نشر من قبل Milan Matos
 تاريخ النشر 2011
  مجال البحث
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The 31S(p,gamma)32Cl reaction is expected to provide the dominant break-out path from the SiP cycle in novae and is important for understanding enrichments of sulfur observed in some nova ejecta. We studied the 32S(3He,t)32Cl charge-exchange reaction to determine properties of proton-unbound levels in 32Cl that have previously contributed significant uncertainties to the 31S(p,gamma)32Cl reaction rate. Measured triton magnetic rigidities were used to determine excitation energies in 32Cl. Proton-branching ratios were obtained by detecting decay protons from unbound 32Cl states in coincidence with tritons. An improved 31S(p,gamma)32Cl reaction rate was calculated including robust statistical and systematic uncertainties.

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