Particle number fluctuations in BCS theory are studied with the relativistic mean-field theory and the shell effects of particle number fluctuations are first discovered. By analyzing the relative errors of the partic...Particle number fluctuations in BCS theory are studied with the relativistic mean-field theory and the shell effects of particle number fluctuations are first discovered. By analyzing the relative errors of the particle number fluctuations, we find that the particle number fluctuations are relevant with the odd-even character. We later apply this method to the examination of the new shell structure, showing that N = 184 for the neutron is indeed a new closed shell.展开更多
Within the relativistic mean field （RMF） theory, the ground state properties of dysprosium isotopes are studied using the shell-model-like approach （SLAP）, in which pairing correlations are treated with particle- ...Within the relativistic mean field （RMF） theory, the ground state properties of dysprosium isotopes are studied using the shell-model-like approach （SLAP）, in which pairing correlations are treated with particle- number conservation, and the Pauli blocking effects are taken into account exactly. For comparison, calculations of the Bardeen Cooper Schrieffer （BCS） model with the RMF are also performed. It is found that the RMF＋SLAP calculation results, as well as the RMF＋BCS ones, reproduce the experimental binding energies and one- and twoneutron separation energies quite well. However, the RMF＋BCS calculations give larger pairing energies than those obtained by the RMF＋SLAP calculations, in particular for nuclei near the proton and neutron drip lines. This deviation is discussed in terms of the BCS particle-number fluctuation, which leads to the sizable deviation of pairing energies between the RMF＋BCS and RMF＋SLAP models, where the fluctuation of the particle number is eliminated automatically.展开更多
基金the National Natural Science Foundation of China(Grant Nos.10475026 and 10235030)the Natural Science Foundation of Zhejiang Province(Grant No. Y604060)
文摘Particle number fluctuations in BCS theory are studied with the relativistic mean-field theory and the shell effects of particle number fluctuations are first discovered. By analyzing the relative errors of the particle number fluctuations, we find that the particle number fluctuations are relevant with the odd-even character. We later apply this method to the examination of the new shell structure, showing that N = 184 for the neutron is indeed a new closed shell.
基金Supported by Fundamental Research Funds for the Central Universities(JUSRP1035)National Natural Science Foundation of China(11305077)
文摘Within the relativistic mean field （RMF） theory, the ground state properties of dysprosium isotopes are studied using the shell-model-like approach （SLAP）, in which pairing correlations are treated with particle- number conservation, and the Pauli blocking effects are taken into account exactly. For comparison, calculations of the Bardeen Cooper Schrieffer （BCS） model with the RMF are also performed. It is found that the RMF＋SLAP calculation results, as well as the RMF＋BCS ones, reproduce the experimental binding energies and one- and twoneutron separation energies quite well. However, the RMF＋BCS calculations give larger pairing energies than those obtained by the RMF＋SLAP calculations, in particular for nuclei near the proton and neutron drip lines. This deviation is discussed in terms of the BCS particle-number fluctuation, which leads to the sizable deviation of pairing energies between the RMF＋BCS and RMF＋SLAP models, where the fluctuation of the particle number is eliminated automatically.
