A Possible γ-Ray Pulsation from PSR J1740-5340B in the Globular Cluster NGC 6397  

作　　者：Jiao Zheng Pengfei Zhang Li Zhang 

机构地区：[1]Department of Astronomy,School of Physics and Astronomy,Key Laboratory of Astroparticle Physics of Yunnan Province,Yunnan University,Kunming 650091,China

出　　处：《Research in Astronomy and Astrophysics》2024年第1期285-291,共7页天文和天体物理学研究（英文版）

基　　金：supported in part by the National Natural Science Foundation of China Nos. 12163006 and 12233006;the Basic Research Program of Yunnan Province No. 202201AT070137;the joint foundation of Department of Science and Technology of Yunnan Province and Yunnan University No. 202201BF070001-020;support by the Xingdian Talent Support Plan-Youth Project。

摘　　要：Recently, a new radio millisecond pulsar(MSP) J1740-5340B, hosted in the globular cluster(GC) NGC 6397,was reported with a 5.78 ms spin period in an eclipsing binary system with a 1.97 days orbital period. Based on a modified radio ephemeris updated by tool tempo2, we analyze the ~15 yr γ-ray data obtained from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detect PSR J1740-5340B's γ-ray pulsation at a confidence level of ~4σ with a weighted H-test value of ~26. By performing a phase-resolved analysis, the γ-ray luminosity in on-pulse interval of PSR J1740-5340B is L_(γ)~ 3.8 × 10^(33) erg s^(-1) using NGC 6397's distance of 2.48 kpc. And γ-rays from the on-pulse part of PSR J1740-5340B contribute ~90% of the total observed γ-ray emissions from NGC 6397. No significant γ-ray pulsation of another MSP J1740-5340A in the GC is detected.Considering that the previous four cases of MSPs in GCs, more data in γ-ray, X-ray, and radio are encouraged to finally confirm the γ-ray emissions from MSP J1740-5340B, especially starving for a precise ephemeris.

关 键 词：gamma-rays:galaxies (stars:)pulsars:individual(PSR J1740-5340B) (Galaxy:)globular clusters:individual(NGC 6397) 

分 类 号：P172.3[天文地球—天文学]