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arXiv · 1404.3603

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

L. Morelli·G. Baiocco·M. D'Agostino·F. Gulminelli·M. Bruno·U. Abbondanno·S. Appannababu·S. Barlini·M. Bini·G. Casini·M. Cinausero·M. Degerlier·D. Fabris·N. Gelli·F. Gramegna·V. L. Kravchuk·T. Marchi·G. Pasquali·S. Piantelli·S. Valdré·Ad R. Raduta
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Abstract

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 $α$-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 $α$-$α$ 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 $α$ emission of $^{24}$Mg at excitation energies well above the threshold for $6-α$ decay.

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L. Morelli, G. Baiocco, M. D'Agostino, F. Gulminelli, M. Bruno, U. Abbondanno, S. Appannababu, S. Barlini, M. Bini, G. Casini, M. Cinausero, M. Degerlier, D. Fabris, N. Gelli, F. Gramegna, V. L. Kravchuk, T. Marchi, G. Pasquali, S. Piantelli, S. Valdré, Ad R. Raduta. 2014-04-14. Non-statistical decay and $α$-correlations in the $^{12}$C+$^{12}$C fusion-evaporation reaction at 95 MeV. https://doi.org/10.1088/0954-3899%2F41%2F7%2F075108

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