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arXiv · 0809.3685

Role of the target orientation angle and orbital angular momentum in the evaporation residue production

Giovanni Fazio·Giorgio Giardina·Francis Hanappe·Giuseppe Mandaglio·Marina Manganaro·Akhtam I. Muminov·Avazbek K. Nasirov·Carmelo Sacca
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Abstract

The influence of the orientation angles of the target nucleus symmetry axis relative to the beam direction on the production of the evaporation residues is investigated for the $^{48}$Ca+$^{154}$Sm reaction as a function of the beam energy. At low energies ($E_{\rm c.m.}<$137 MeV), the yield of evaporation residues is observed only for collisions with small orientation angles ($α_T<45^0$). At large energies (about $E_{\rm c.m.}=$140--180 MeV) all the orientation angles $α_T$ can contribute to the evaporation residue cross section $σ_{ER}$ in the 10--100 mb range, and at $E_{c.m.}>$180 MeV $σ_{ER}$ ranges around 0.1--10 mb because the fission barrier for a compound nucleus decreases by increasing its excitation energy and angular momentum.

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Giovanni Fazio, Giorgio Giardina, Francis Hanappe, Giuseppe Mandaglio, Marina Manganaro, Akhtam I. Muminov, Avazbek K. Nasirov, Carmelo Sacca. 2008-09-22. Role of the target orientation angle and orbital angular momentum in the evaporation residue production. https://doi.org/10.1143/jpsj.77.124201

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