Charged particle decay of hot and rotatingMo88nuclei in fusion-evaporation reactions

Abstract

A study of fusion-evaporation and (partly) fusion-fission channels for the 88 Mo compound nucleus, produced at different excitation energies in the reaction 48 Ti + 40 Ca at 300, 450 and 600 MeV beam energies, is presented. Fusion-evaporation and fusion-fission cross sections have been extracted and compared with the existing systematics. Experimental data concerning light charged particles have been compared with the prediction of the statistical model in its implementation in the Gemini++ code, well suited even for high spin systems, in order to tune the main model parameters in a mass region not abundantly covered by exclusive experimental data. Multiplicities for light charged particles emitted in fusion evaporation events are also presented. Some discrepancies with respect to the prediction of the statistical model have been found for forward emitted α-particles; they may be due both to pre-equilibrium emission and to reaction channels (such as Deep Inelastic Collisions, QuasiFission/QuasiFusion) different from the compound nucleus formation.

Isospin diffusion in binary collisions of S32+Ca40,48 and Piantelli1, Valdré2, Barlini3 et al. 2017Phys. Rev. CSelf Cite15270View full textAdd to dashboardCite

“…This effect, which takes place also in the experimental case, coupled to the fact that often only one fragment of a binary event is experimentally detected because of the geometrical cuts and identification thresholds, introduces uncertainties in the experimental classification of the events, as it has been pointed out, e.g., in Ref. [43].…”

Trends in particle and nuclei identification techniques in nuclear physics experiments

“…The NUCLEX collaboration studies the behaviour of nuclear matter in a wide range of beam energies (5-100 MeV/nucleon) using different setups and particle identification techniques. This diversification is needed to better investigate phenomena typical of different energy regimes: compound nucleus formation and decay [62], α-clustering [63], charged particle spectroscopy [64], isospin transport mechanisms [65][66][67] and neck emissions [68]. Various setups have been developed and used at LNS, LNL and GANIL: FAZIA [69,70], GARFIELD [71], OSCAR [72] and the ACTAR demonstrator [73].…”

Constraining Hot Sources in Central Heavy-ion Collisions Below 20 MeV/$u$

“…To highlight this kind of emission, data were compared with results from statistical model codes (GEMINI++ [9] and PACE4). In this direction, for the experiment "I", a fine tuning of GEMINI++ parameters was performed at the lower bombarding energy [1], in the hypothesis of a pure complete fusion. When the energy increases, an excess of α-particle evaporation at forward angles also increases up to ∼ 20% of the total emission, as shown in Fig.…”

“…In this work, we consider three experiments in which the investigation of a non-statistical emission was relevant for the fusion-evaporation (F-E) reaction channel. First, we will examine a study on the Giant Dipole Resonance (GDR) evolution (experiment "I") in which the fusion reaction 48 Ti+ 40 Ca at three bombarding energies (6.25; 9.38; 12.5 MeV/u) [1] is considered. Here, it is very important to ascertain whether the pre-equilibrium contribution remains negligible at the three beam energies.…”