Analysis of Bright Source Hardness Ratios in the 4 yr Insight-HXMT Galactic Plane Scanning Survey Catalog  

作　　者：Chen Wang Jin-Yuan Liao Ju Guan Yuan Liu Cheng-Kui Li Na Sai Jing Jin Shuang-Nan Zhang 

机构地区：[1]Key Laboratory of Space Astronomy and Technology,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [4]Department of Astronomy,School of Physics and Technology,Wuhan University,Wuhan 430072,China [5]WHU-NAOC Joint Center for Astronomy,Wuhan University,Wuhan 430072,China

出　　处：《Research in Astronomy and Astrophysics》2024年第2期154-170,共17页天文和天体物理学研究（英文版）

基　　金：the support from the National Natural Science Foundation of China under grant Nos.12333007,U1838202,U1838201,U1838107,U1838113,U1838113 and U2038102;the Youth Innovation Promotion Association of the CAS(grant id 2018014);the National Key R&D Program of China(grant No.2021YFA0718500);partially supported by the International Partnership Program of the Chinese Academy of Sciences(grant No.113111KYSB20190020)。

摘　　要：We conduct a statistical analysis of the hardness ratio(HR)for bright sources in the 4 yr Galactic Plane Scanning Survey catalog of Insight-HXMT.Depending on the stable(variable)flux F_(s)(F_(v))or spectrum S_(s)(S_(v))of each source,the bright sources are classified into three groups:F_(v)&S_(v),F_(v)&S_(s),and F_(s)&_(s).Our study of the HR characteristics in different types of sources reveals that accretion-powered neutron star(NS)low-mass X-ray binaries(LMXBs)exhibit softer energy spectra than NS high-mass X-ray binaries(HMXBs),but harder energy spectra than black hole binaries in most cases.This difference is probably due to their different magnetic field strengths.Additionally,Fv&Sv LMXBs tend to be harder than Fv&Ss LMXBs below 7 keV,while the opposite is true for HMXBs.Our results suggest that LMXBs may dominate unclassified sources,and NS binaries are likely to be the primary type of X-ray binaries with ambiguous compact stars.By comparing the HR of transient sources in their outburst and low-flux states,it is found that the averaged HR of four sources in the two states are roughly comparable within uncertainties.We also investigate the spatial properties of the three groups and find that Fv&Sv sources are mainly located in the longitude of-20°<l<9°,Fv&Ss sources cross the Galactic Plane,and Fs&Ss sources are predominantly concentrated in 19°<l<42°.In addition,analyzing the HR spatial distributions shows the absorption of soft X-rays(primarily below 2 keV)in the Galactic Plane.

关 键 词：catalogs-surveys-methods data analysis-X-rays general 

分 类 号：P156[天文地球—天文学]