The Nucleon Direct Urca Processes in a Cooling Neutron Star  

作　　者：XU Yan LIU Guang-Zhou LIU Cheng-Zhi FAN Cun-Bo WANG Hong-Yan ZHU Ming-Feng ZHAO En-Guang 许妍;刘广洲;刘承志;范存波;王红岩;朱明枫;赵恩广(Changchun Observatory,National Astronomical Observatories,Chinese Academy of Sciences,Changchun 130117;Center for Theoretical Physics,Jilin University,Changchun 130012;College of Physics,Beihua University,Jilin 132013;Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100190)

机构地区：[1]Changchun Observatory,National Astronomical Observatories,Chinese Academy of Sciences,Changchun 130117 [2]Center for Theoretical Physics,Jilin University,Changchun 130012 [3]College of Physics,Beihua University,Jilin 132013 [4]Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100190

出　　处：《Chinese Physics Letters》2013年第12期191-194,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant Nos 11075063,11073033,11247312 and 11103047.

摘　　要：In the relativistic mean field approximation,the relativistic energy losses of the nucleon direct Urca processes are studied in the degenerate baryon matter of neutron stars.We investigate the effects of hyperon degrees of freedom and the isovector scalar interaction which is considered by exchangingδmeson on the nucleon direct Urca processes in neutron star matter.The results indicate that the existence of hyperons decreases the abundance of protons and leptons and can sharply suppress the neutrino emissivity of the nucleon direct Urca processes,while it has only a little influence on the neutrino luminosity for a fixed neutron star whetherδmesons appear in a neutron star or not.However,the presence ofδmesons can result in obvious growth in the neutrino emissivity and luminosity which will speed up the cooling rate for the nonsuperfluid neutron star.

关 键 词：MESON RELATIVISTIC sharply 

分 类 号：O57[理学—粒子物理与原子核物理]