51. Experimental determination of fragment excitation energies in multifragmentation events
- Author
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M.F. Rivet, J.F. Lecolley, R. Bougault, C. Volant, Ph. Buchet, J. Colin, Marie Germain, R. Legrain, D. Guinet, G. Tabacaru, J. B. Natowitz, A. Chbihi, M. Assenard, E. Rosato, J.C. Steckmeyer, Ch.O. Bacri, A. Le Fèvre, Z. Majka, J.D. Frankland, J.L. Charvet, D. Gourio, Bernard Borderie, Ph. Eudes, J. Cibor, E. Gerlic, E. Genouin-Duhamel, D. Doré, A. Demeyer, D. Durand, L. Gingras, F. Bocage, G. Auger, S. Salou, E. Plagnol, J.P. Wieleczko, O. Tirel, T. Reposeur, M. Parlog, E. Vient, R. Brou, K. Hagel, A.D. Nguyen, D. Cussol, A. Rahmani, O. Lopez, N. Le Neindre, R. Wada, B. Tamain, A. M. Maskay, F. Saint-Laurent, T. Lefort, E. Galichet, M. Stern, L. Nalpas, R. Dayras, J.L. Laville, Jean Péter, Nathalie Marie, P. Lautesse, and M. Louvel
- Subjects
Thermal equilibrium ,Physics ,Nuclear and High Energy Physics ,Excited state ,Atomic number ,Atomic physics ,Nuclear Experiment ,Kinetic energy ,Nucleon ,Isotopes of helium ,Charged particle ,Excitation ,Nuclear Physics - Abstract
For 50 MeV/nucleon {sup 129}Xe+{sup nat}Sn multifragmentation events, we deduced, by means of correlation techniques, the multiplicities of the hydrogen and helium isotopes which were emitted by the hot primary excited fragments produced at the stage of the disassembly of an equilibrated hot source. We also derived the relative kinetic energy distributions between the primary clusters and the light charged particles that they evaporate. From the comparison between the secondary multiplicities observed experimentally and the multiplicities predicted by the GEMINI model, we concluded that the source breaks into primary fragments which are characterized by the same N/Z ratio as the combined system. Knowing the secondary light charged particle multiplicities and kinetic energies, we reconstructed the average charges of the hot fragments and we estimated their mean excitation energies. The fragment excitation energies are equal to 3.0 MeV/nucleon for the full range of intermediate mass fragment atomic number. This global constancy indicates that, on the average, thermodynamical equilibrium was achieved at the disassembly stage of the source. {copyright} {ital 1998} {ital The American Physical Society}
- Published
- 1998