High-spin states in 84 Rb have been studied by using the 70Zn(18O, p3n)84Rb reaction at beam energy of 75MeV. Three regular magnetic dipole bands including strong M1 and weak E2 transitions have been observed in this ...High-spin states in 84 Rb have been studied by using the 70Zn(18O, p3n)84Rb reaction at beam energy of 75MeV. Three regular magnetic dipole bands including strong M1 and weak E2 transitions have been observed in this nucleus which shows the characteristic feature of magnetic rotation. These bands are interpreted in the projected shell model for the first time on the basis of the four-quasiparticle configuration of the type π(fp)π(g29/2)v(g9/2). It is shown that the calculated sequence lies roughly in the same energy range as the experimental one but the interval between neighboring levels is larger than the corresponding experimental value. We believe that a 4-quasiparticle band crossing with the 2-quasiparticle band will depress the energies of the states.展开更多
The projected shell model is applied to the nucleus 129La. The present results of theoretical calculations about the one-quasiproton bands are compared with experimental data. The agreement with both the yrast πh11/2...The projected shell model is applied to the nucleus 129La. The present results of theoretical calculations about the one-quasiproton bands are compared with experimental data. The agreement with both the yrast πh11/2 band πg7/2 band is satisfactory. We also assign the πg7/2 [νh11/2]2 configuration with an oblate shape for one of bands in 129La.展开更多
High spin states of 84Sr were populated through the reaction 70Zn(18O,4n)84Sr at 75 MeV beam energy.Measurement of excitation function,γ-γ coincidences,directional correlation from oriented state (DCO) ratios and γ...High spin states of 84Sr were populated through the reaction 70Zn(18O,4n)84Sr at 75 MeV beam energy.Measurement of excitation function,γ-γ coincidences,directional correlation from oriented state (DCO) ratios and γ-transition intensities were performed using eight anticompton HPGe detectors and one planar HPGe detector.Based on the measured results,a new level scheme of 84Sr was established in which 12 new states and nearly 30 new γ-transitions were identified in the present work.The positive-parity states of the new level scheme were compared with the results from calculations in the framework of the projected shell model (PSM).One negative-parity band was extended to spin Iπ=19-and it can be found that in the high spin states,the γ-transition energies show the nature of signature staggering.The negative-parity band levels are in good agreement with deformed configuration-mixing shell model (DCM) calculations.展开更多
基金Supported by Suranaree University of Technology(No.15/2553)Major State Basic Research Development Program in China(No.2007CB815003)+1 种基金National Natural Science Foundation of China(Nos.10975190,11065001,10975019,10675170,and 61067001)Foundation of the Education Department of Jiangxi Province(No.GJJ12372)
文摘High-spin states in 84 Rb have been studied by using the 70Zn(18O, p3n)84Rb reaction at beam energy of 75MeV. Three regular magnetic dipole bands including strong M1 and weak E2 transitions have been observed in this nucleus which shows the characteristic feature of magnetic rotation. These bands are interpreted in the projected shell model for the first time on the basis of the four-quasiparticle configuration of the type π(fp)π(g29/2)v(g9/2). It is shown that the calculated sequence lies roughly in the same energy range as the experimental one but the interval between neighboring levels is larger than the corresponding experimental value. We believe that a 4-quasiparticle band crossing with the 2-quasiparticle band will depress the energies of the states.
文摘The projected shell model is applied to the nucleus 129La. The present results of theoretical calculations about the one-quasiproton bands are compared with experimental data. The agreement with both the yrast πh11/2 band πg7/2 band is satisfactory. We also assign the πg7/2 [νh11/2]2 configuration with an oblate shape for one of bands in 129La.
基金supported by the Major State Basic Research Development Program in China (Grant No. 2007CB815003)the National Natural Science Foundation of China (Grant Nos. 11065001, 10547140, 10525520,60476043,10675170,10475002 and 10775064)+4 种基金the U.S. National Science Foundation (Grant No. 0500291)the Southeastern Universities Research Association,the Natural Science Foundation of Jiangxi Province (Grant Nos. 0612003 and 2007GZW0476)the LSU - LNNU Joint Research Program (Grant No. 9961)the Foundation of the Education Department of Jiangxi Province (Grant No. [2007]235)the Liaoning Education Department Fund (Grant No. 20060464)
文摘High spin states of 84Sr were populated through the reaction 70Zn(18O,4n)84Sr at 75 MeV beam energy.Measurement of excitation function,γ-γ coincidences,directional correlation from oriented state (DCO) ratios and γ-transition intensities were performed using eight anticompton HPGe detectors and one planar HPGe detector.Based on the measured results,a new level scheme of 84Sr was established in which 12 new states and nearly 30 new γ-transitions were identified in the present work.The positive-parity states of the new level scheme were compared with the results from calculations in the framework of the projected shell model (PSM).One negative-parity band was extended to spin Iπ=19-and it can be found that in the high spin states,the γ-transition energies show the nature of signature staggering.The negative-parity band levels are in good agreement with deformed configuration-mixing shell model (DCM) calculations.