Searching for the Highest Energy of Pulsation and Critical Luminosity of Swift J0243.6+6124 Observed by Insight-HXMT

作     者：Qing-Xia Zhao Xian Hou Ming-Yu Ge Shuang-Nan Zhang Yun-Xiang Xiao You-Li Tuo Zi-Xu Yang Ling-Da Kong Jin-Lu Qu Shu Zhang Jian-Cheng Wang 

作者机构：Yunnan ObservatoriesChinese Academy of SciencesKunming 650216China Key Laboratory of Particle AstrophysicsInstitute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of SciencesChineseAcademy of SciencesBeijing 100049China Key Laboratory for the Structure and Evolution of Celestial ObjectsChinese Academy of SciencesKunming 650216China Institut fur Astronomic und AstrophysikSand 1D-72076 TabingenGemany School of Physics and Optoelectronic EngineeringShandong University of TechnologyZibo 255000China 

出 版 物：《Research in Astronomy and Astrophysics》 (天文和天体物理学研究（英文版）)

年 卷 期：2024年第24卷第5期

页      面：61-69页

核心收录：

学科分类：07[理学] 070202[理学-粒子物理与原子核物理] 0704[理学-天文学] 0702[理学-物理学] 

基　　金：project funded by China National Space Administration(CNSA) the Chinese Academy of Sciences(CAS) supported by the National Key R&D Program of China(2021YFA0718500 and 2023YFE0101200)from the Minister of Science and Technology of China(MOST) supports from the National Natural Science Foundation of China under grants 12373051 and 12333007 supported by International Partnership Program of Chinese Academy of Sciences(grant No.113111KYSB20190020)。 

主　　题：(stars:)pulsars-individual(Swift J0243.6+6124)-X-rays binaries–stars neutron 

摘      要：Owing to the broad energy coverage of Insight-HXMT in the hard X-ray band,we detected the highest energy of pulsation exceeding 200 keV around the 2017–2018 outburst peak of the first Galactic pulsating ultraluminous X-ray source (PULX) Swift J0243.6+6124,which is the highest energy detected from PULXs to date.We also obtained the highest energy of pulsation of every exposure during the outburst in 2017–2018,and found the highest energy is roughly positively correlated with luminosity.Using our newly developed method,we identified the critical luminosity being 4×10~(38)erg s~(-1) when the main peaks of the low and high energy pulse profiles became aligned,which separates the fan-beam dominated and pencil-beam dominated accretion regimes.Above the critical luminosity,the phase of the main peak shifted gradually from 0.5 to 0.8 until the outburst peak in al energy bands is reached,which is in agreement with the phase shift found previously at low energies.Our result is consistent with what is derived from spectral analysis.