Evaporation residue cross sections for 40Ca + 48Ti at 25.0 and 33.9 MeV per nucleon

Abstract

The fusion and subsequent decay of the system 40 Ca+ 48 Ti has been studied at 25.0 and 33.9 MeV per nucleon bombarding energies. Heavy residues were detected in coincidence with light particles, and evaporation residue cross sections have been extracted. Light particle distributions are well described by a simple kinematical model, and from this the average excitation energies of the system were determined.

Limiting excitation energy for GDR gamma decay

“…From simple kinematical calculations, confirmed by GEMINI [9] simulations, we expect around this energy evaporation residues (ER) produced in fusion-like reactions. This assignment is also confirmed by a recent work on the 40 Ca + 48 Ti reaction [16] measured at the same beam energy. The separation between dissipative and fusion-like reactions can be observed in fig.…”

“…To evaluate the excitation energy and mass of the equilibrated compound nucleus formed in these fusion-like reactions, we used the results of ref. [16] where the reaction 40 Ca + 48 Ti at 25 A MeV was measured. A mass of 63 ± 2 amu and an excitation energy of 337 ± 25 MeV was extracted in [16].…”

“…[16] where the reaction 40 Ca + 48 Ti at 25 A MeV was measured. A mass of 63 ± 2 amu and an excitation energy of 337 ± 25 MeV was extracted in [16]. Starting from these values, the average mass and excitation energy of our systems was estimated by correcting for the Q-values.…”

N/Z effects on40,48Ca+40,48Ca reactions at 25 MeV/nucleon

“…An important fraction of the cross-section of semi-central events for the studied systems at 25 MeV/nucleon is due to complete and incomplete fu- sion phenomena [12]. It is interesting to investigate if the fusion-like source keeps memory of the N/Z of entrance channel or, in other words, if preequilibrium emitted light particles modify the original N/Z rank of the studied systems.…”