Nucleon direct-semidirect radiative capture with Skyrme-Hartree-Fock-BCS bound states

スキルムハートリーフォックの束縛状態を用いる核子の直接及び半直接放射捕獲

Bonearu, L.*; 河野 俊彦*; 渡邊 健人*; 千葉 敏

Bonearu, L.*; Kawano, Toshihiko*; Watanabe, Takehito*; Chiba, Satoshi

核子の直接及び半直接捕獲反応(DSD)断面積をハートリーフォックBCS束縛状態への遷移として計算した。変形核に対しては一粒子状態を軸対称の調和振動子基底で展開し、球対称基底に射影することにより求めた。対相関はBCS理論に基づき、スペクトロスコピック因子の計算値はSnからSnに対して測定値をよく再現した。PbとUの中性子DSD捕獲断面積は測定値と良く一致した。r過程で重要なSnとSnについての計算も行った。

The nucleon direct-semidirect (DSD) capture cross sections are obtained by calculating a transition amplitude to the Hartree-Fock-BCS bound states. The radial matrix elements in the DSD amplitudes are calculated from the radial part of the single-particle wave functions. For deformed nuclei the single-particle states are expanded in the cylindrical harmonic-oscillator basis and then projected on the spherical harmonic-oscillator basis. The pairing correlations are treated in the BCS approach and the calculated spectroscopic factors are in fairly good agreement with experimental data in the even tin isotopes from Sn to Sn. The resulting DSD cross sections for the neutron capture by Pb and U are found to be in good agreement with the available experimental data. The calculations are also performed for the neutron capture on Sn and Sn isotopes that are important for ther-process in astrophysics.