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arXiv · 1804.06294

Experimental study of precisely selected evaporation chains in the decay of excited $^{25}$Mg

A. Camaiani·G. Casini·L. Morelli·S. Barlini·S. Piantelli·G. Baiocco·M. Bini·M. Bruno·A. Buccola·M. Cinausero·M. Cicerchia·M. D'Agostino·M. Degelier·D. Fabris·C. Frosin·F. Gramegna·F. Gulminelli·G. Mantovani·T. Marchi·A. Olmi·P. Ottanelli·G. Pasquali·G. Pastore·S. Valdre·G. Verde
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Abstract

The reaction $^{12}$C + $^{13}$C at 95 MeV bombarding energy is studied using the GARFIELD + Ring Counter apparatus located at the INFN Laboratori Nazionali di Legnaro. In this paper we want to investigate the de-excitation of $^{25}$Mg aiming both at a new stringent test of the statistical description of nuclear decay and a direct comparison with the decay of the system $^{24}$Mg formed through $^{12}$C+$^{12}$C reactions previously studied. Thanks to the large acceptance of the detector and to its good fragment identification capabilities, we could apply stringent selections on fusion-evaporation events, requiring their completeness in charge. The main decay features of the evaporation residues and of the emitted light particles are overall well described by a pure statistical model; however, as for the case of the previously studied 24Mg, we observed some deviations in the branching ratios, in particular for those chains involving only the evaporation of $α$ particles. From this point of view the behavior of the $^{24}$Mg and $^{25}$Mg decay cases appear to be rather similar. An attempt to obtain a full mass balance even without neutron detection is also discussed.

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A. Camaiani, G. Casini, L. Morelli, S. Barlini, S. Piantelli, G. Baiocco, M. Bini, M. Bruno, A. Buccola, M. Cinausero, M. Cicerchia, M. D'Agostino, M. Degelier, D. Fabris, C. Frosin, F. Gramegna, F. Gulminelli, G. Mantovani, T. Marchi, A. Olmi, P. Ottanelli, G. Pasquali, G. Pastore, S. Valdre, G. Verde. 2020-10-01. Experimental study of precisely selected evaporation chains in the decay of excited $^{25}$Mg. https://doi.org/10.1103/physrevc.97.044607

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