Multiplicities For Evaporative 4He Emission In Heavy Ion Reactions: Relationships To Spin And Lifetime Expectancy Of The Composite Nucleus
Multiplicities are compared for4He evaporation in reactions of40Ar and56Fe projectiles (8.5 MeV/u) with withnatAg and238U targets. Coincidence requirements involving fusion-fission and projectile-like fragments have been used to select separate entrance-channel spin zones. Evaporation-like4He emission from the composite nuclei is shown to be large for mean spins ≦100ℏ, and to decrease dramatically with increasing spin. Coincidence measurements between two4He particles have also been studied for40Ar+natAg. This requirement is shown to select reactions that lead to evaporation residues and therefore to a zone of relatively low spin. The shapes of the4He spectra provide an interesting probe of the mechanism and also of the thermodynamic properties of hot nuclei.
Repository citation: Ajitanand, N. N.; Alexander, John M.; Delagrange, H.; Duek, E.; Eriksen, D. Ø.; Guerreau, D.; Kaplan, Morton; Kildir, M.; Kowalski, L.; Lacey, R.; Logan, D.; Moses, D. J.; Peaslee, Graham F.; Vaz, Louis C.; and Zisman, M. S., "Multiplicities For Evaporative 4He Emission In Heavy Ion Reactions: Relationships To Spin And Lifetime Expectancy Of The Composite Nucleus" (1984). Faculty Publications. Paper 1123.
Published in: Zeitschrift für Physik A Atoms and Nuclei, Volume 316, Issue 2, June 1, 1984, pages 169-176. Copyright © 1984 Springer-Verlag.