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Non-statistical decay and $alpha$-correlations in the $^{12}$C+$^{12}$C fusion-evaporation reaction at 95 MeV

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 نشر من قبل Francesca Gulminelli Dr
 تاريخ النشر 2014
  مجال البحث
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Multiple alpha coincidence and correlations are studied in the reaction $^{12}$C+$^{12}$C at 95 MeV for fusion-evaporation events completely detected in charge. Two specific channels with Carbon and Oxygen residues in coincidence with $alpha$-particles are addressed, which are associated with anomalously high branching ratios with respect the predictions by Hauser-Feshbach calculations. Triple alpha emission appears kinematically compatible with a sequential emission from a highly excited Mg. The phase space distribution of $alpha$-$alpha$ coincidences suggests a correlated emission from a Mg compound, leaving an Oxygen residue excited above the threshold for neutron decay. These observations indicate a preferential $alpha$ emission of $^{24}$Mg at excitation energies well above the threshold for $6-alpha$ decay.



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