ムトウ　タクミ   Takumi Muto   武藤　巧    所属   千葉工業大学  情報変革科学部 教育センター（情報変革科学部）    職種   教授
言語種別	英語
発行・発表の年月	2012
形態種別	国際会議プロシーディングス
標題	Quark beta decay in an inhomogeneous chiral phase and cooling of hybrid stars
執筆形態	共著
掲載誌名	Proceedings of Science (The XII International Symposium on Nuclei in the Cosmos)
掲載区分	国外
巻・号・頁	pp.237-243
著者・共著者	Takumi Muto, Toshitaka Tatsumi
概要	We discuss the cooling of hybrid stars by considering the neutrino emission from quark matter. As a current topic the appearance of various inhomogeneous chiral phases have been studied near the chiral transition. Here we consider the dual-chiral-density -wave (DCDW) specified by the spatially modulated quark condensates. Since the DCDW state can be represented as a chirally rotated state from the normal quark matter, the quark weak current is accordingly transformed to have an additional phase factor which modifies the energy-momentum conservation at the vertex, and makes the quark direct Urca process possible. The direct evaluation of the neutrino emissivity shows that it is proportional to T^6 and the magnitude is comparable with the quark or pion cooling. Since the DCDW phase develops only in the limited density region, this novel mechanism may give an interesting scenario about cooling of hybrid stars that lower-mass stars should be cooler than higher-mass ones.