Light particles spectra in coincidence with fission fragments have been measured for the reaction 187 MeV Cl-37 on Sn-120 populating Ho-157 compound nuclei at the excitation energy E-x = 85 MeV. The experimental neutron pre-scission multiplicity for symmetric splitting is two times larger than the statistical model estimate. The experimental multiplicity is reproduced by calculations in which a fission delay, in agreement with systematics, is introduced. This empirical fission delay produces a sizeable increase, with respect to the standard statistical model estimate, of the survival probability against fission for nuclei with angular momentum around J similar to 75 (h) over bar. The importance of this effect in the population of superdeformed and hyperdeformed structures in the evaporation residues is discussed.
Pre-scission emission and evaporation residues survival probability in the reaction 37Cl+120Sn at 187 MeV / L., Fiore; G., D’Erasmo; D., Di Santo; L., Celano; N., Colonna; E. M., Fiore; A., Pantaleo; V., Paticchio; G., Tagliente; G., Viesti; D., Fabris; G., Nebbia; M., Cinausero; E., Fioretto; G., Prete; Brondi, Augusto; LA RANA, Giovanni; Moro, RENATA EMILIA MARIA; Vardaci, Emanuele; F., Lucarelli; P. F., Bortignon. - In: NUCLEAR PHYSICS. A. - ISSN 0375-9474. - STAMPA. - 620:1(1997), pp. 71-80. [10.1016/S0375-9474(97)00154-1]
Pre-scission emission and evaporation residues survival probability in the reaction 37Cl+120Sn at 187 MeV
BRONDI, AUGUSTO;LA RANA, GIOVANNI;MORO, RENATA EMILIA MARIA;VARDACI, EMANUELE;
1997
Abstract
Light particles spectra in coincidence with fission fragments have been measured for the reaction 187 MeV Cl-37 on Sn-120 populating Ho-157 compound nuclei at the excitation energy E-x = 85 MeV. The experimental neutron pre-scission multiplicity for symmetric splitting is two times larger than the statistical model estimate. The experimental multiplicity is reproduced by calculations in which a fission delay, in agreement with systematics, is introduced. This empirical fission delay produces a sizeable increase, with respect to the standard statistical model estimate, of the survival probability against fission for nuclei with angular momentum around J similar to 75 (h) over bar. The importance of this effect in the population of superdeformed and hyperdeformed structures in the evaporation residues is discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
