Chiral condensate at finite density using the chiral Ward identity

• 郷田, 創一郎

• Jido, Daisuke

抄録

To study partial restoration of the chiral symmetry at finite density, we investigate the density corrections of the chiral condensate up to the next-to-leading order of density expansion using the chiral Ward identity and an in-medium chiral perturbation theory. In our study, we assume that all the in-vacuum quantities for the pion, the nucleon, and the πN interaction are determined in vacuum and focus on density expansion of the in-medium physical quantities. We perform diagrammatic analysis of the correlation functions which provide the in-medium chiral condensate. This density expansion scheme shows that the medium effect to the chiral condensate beyond the linear density comes from density corrections to the πN σ term as a result of the interactions between pion and nucleon in nuclear matter. We also discuss that higher-density contributions beyond the order of ρ2 cannot be fixed only by the in-vacuum πN dynamics and we encounter divergence in the calculation of the ρ2-order corrections of the chiral condensate. To remove the divergence, we need NN two-body contact interaction, which can be fixed in vacuum.

収録刊行物

• Physical Review C

  Physical Review C 88 (6), 2013-12-19

  American Physical Society

詳細情報

• CRID: 1050564285736739712
• NII論文ID: 120005385855
• NII書誌ID: AA00773613
• ISSN: 05562813
• HANDLE: 2433/182888
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
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  • CiNii Articles