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Cross-section measurements of radiative proton-capture reactions in $^{112}$Cd at energies of astrophysical interest

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 نشر من قبل Athanasios Psaltis
 تاريخ النشر 2019
  مجال البحث
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Reactions involving the group of nuclei commonly known as p nuclei are part of the nucleosynthetic mechanisms at astrophysical sites. The $^{113}$In nucleus is such a case with several open questions regarding its origin at extreme stellar environments. In this work, the experimental study of the cross sections of the radiative proton-capture reaction $^{112}$Cd(p,$gamma$)$^{113}$In is attempted for the first time at energies lying inside the Gamow window with an isotopically enriched $^{112}$Cd target. Two different techniques, the in-beam $gamma$-ray spectroscopy and the activation method, have been applied. The latter method is required to account for the presence of a low-lying $^{113}$In isomer at 392 keV having a halflife of $approx 100$ min. From the cross sections, the astrophysical S factors and the isomeric ratios have been additionally deduced. The experimental results are compared to detailed Hauser-Feshbach theoretical calculations using TALYS, and discussed in terms of their significance to the optical model potential involved.

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