Fusion-evaporation cross sections of^(238)U(^(9)Be,5n)^(242)Cm are measured over a wide energy range around the Coulomb barrier.These measured cross sections are compared with model calculations using two codes,namely...Fusion-evaporation cross sections of^(238)U(^(9)Be,5n)^(242)Cm are measured over a wide energy range around the Coulomb barrier.These measured cross sections are compared with model calculations using two codes,namely HIVAP2 and KE WPIE2.HIVAP2 calculations overestimate the measured fusion-evaporation cross sections by a factor of approximately 3.In KEWPIE2 calculations,two approaches,namely the Wentzel-Kramers-Brillouin(WKB)approximation and the empirical barrier-distribution(EBD)method,are used for the capture probability;both of them properly describe the measured cross sections.Additionally,fusion cross sections of^(7.9)Be+^(238)Umeas-ured in two experiments are applied to constrain model calculations further through three codes,i.e,HIVAP2,KEWPIE2,and CCFULL.Parameters in these codes are also examined by comparison with measured fusion cross sections.AIll the comparisons indicate that the K EWPIE2 calculations using the WKB approximation agree well with the measured cross sections of both fusion reactions 7.9 Be+^(238)U and the fusion-evaporation reaction 238U(9 Be,5n)242 Cm.Calculations using the fusion code CCFULL are also in good agreement with the measured fusion cross sections of 7.9 Be+^(238)U.展开更多
基金the National Natural Science Foundation of China(12005314,11805289,11875328,11775316)the ELI-NP Phase II,a project co-financed by the Romanian Government and the European Union through the European Regional Development Fund-the Competitiv eness Operational Programme(1/07.07.2016,COP,ID 1334)。
文摘Fusion-evaporation cross sections of^(238)U(^(9)Be,5n)^(242)Cm are measured over a wide energy range around the Coulomb barrier.These measured cross sections are compared with model calculations using two codes,namely HIVAP2 and KE WPIE2.HIVAP2 calculations overestimate the measured fusion-evaporation cross sections by a factor of approximately 3.In KEWPIE2 calculations,two approaches,namely the Wentzel-Kramers-Brillouin(WKB)approximation and the empirical barrier-distribution(EBD)method,are used for the capture probability;both of them properly describe the measured cross sections.Additionally,fusion cross sections of^(7.9)Be+^(238)Umeas-ured in two experiments are applied to constrain model calculations further through three codes,i.e,HIVAP2,KEWPIE2,and CCFULL.Parameters in these codes are also examined by comparison with measured fusion cross sections.AIll the comparisons indicate that the K EWPIE2 calculations using the WKB approximation agree well with the measured cross sections of both fusion reactions 7.9 Be+^(238)U and the fusion-evaporation reaction 238U(9 Be,5n)242 Cm.Calculations using the fusion code CCFULL are also in good agreement with the measured fusion cross sections of 7.9 Be+^(238)U.
