Origin of Unexpected Isotopic Trends in Synthesis of Superheavy Nuclei
LIU Zu-Hua 1,3, BAO Jing-Dong 1,2
1Key Laboratory of Beam Technology and Material Modification (Ministry of Education), Beijing Normal University, Beijing 100875
2Department of Physics, Beijing Normal University, Beijing 100875
3China Institute of Atomic Energy, Beijing 102413
Origin of Unexpected Isotopic Trends in Synthesis of Superheavy Nuclei
LIU Zu-Hua 1,3;BAO Jing-Dong 1,2
1Key Laboratory of Beam Technology and Material Modification (Ministry of Education), Beijing Normal University, Beijing 100875
2Department of Physics, Beijing Normal University, Beijing 100875
3China Institute of Atomic Energy, Beijing 102413
摘要We investigate the dependence of the yield of superheavy nuclei with Z=110, 112, 114 on the neutron excess of the projectile nucleus with a two-parameter Smoluchowski equation. It is confirmed that in some cases, the cold fusion reactions with less neutron excess are more favourable than those with more neutron excess. In order to probe the origin of these unexpected isotopic trends, we also investigate the probabilities of capture, fusion and survival in the cold fusion reactions in detail. It is found that the maximal ER cross sections of the superheavy nuclei exponentially increase as a function of Bf-Sn with Bf being the fission barrier and Sn being the neutron separation energy. Although the probabilities of capture and fusion have some influences, the unexpected isotopic trends mainly due to the ependence of the ER cross sections on the Bf-Sn value. Therefore, the reactions with larger Bf-Sn values should be more favourable for synthesis of superheavy nuclei.
We investigate the dependence of the yield of superheavy nuclei with Z=110, 112, 114 on the neutron excess of the projectile nucleus with a two-parameter Smoluchowski equation. It is confirmed that in some cases, the cold fusion reactions with less neutron excess are more favourable than those with more neutron excess. In order to probe the origin of these unexpected isotopic trends, we also investigate the probabilities of capture, fusion and survival in the cold fusion reactions in detail. It is found that the maximal ER cross sections of the superheavy nuclei exponentially increase as a function of Bf-Sn with Bf being the fission barrier and Sn being the neutron separation energy. Although the probabilities of capture and fusion have some influences, the unexpected isotopic trends mainly due to the ependence of the ER cross sections on the Bf-Sn value. Therefore, the reactions with larger Bf-Sn values should be more favourable for synthesis of superheavy nuclei.
LIU Zu-Hua;BAO Jing-Dong;. Origin of Unexpected Isotopic Trends in Synthesis of Superheavy Nuclei[J]. 中国物理快报, 2007, 24(2): 393-396.
LIU Zu-Hua, BAO Jing-Dong,. Origin of Unexpected Isotopic Trends in Synthesis of Superheavy Nuclei. Chin. Phys. Lett., 2007, 24(2): 393-396.
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