Gamma-ray emission from globular clusters 2MS-GC01, IC 1257, NGC5904, NGC6656 and FSR1735

• Published in: arXiv.org
• Main Authors: Zhou, J N, Zhang, P F, Huang, X Y, X Li, Liang, Y F, L Fu, Yan, J Z, Liu, Q Z
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 26.01.2015
• Subjects: Emission; Emitters; Galactic clusters; Galaxies; Gamma rays; Globular clusters; Millisecond pulsars; Physics - High Energy Astrophysical Phenomena
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1501.06341

Globular clusters (GCs) are the oldest stellar system in the Galaxy, in which the millisecond pulsars are widely believed to be the only steady {\gamma}-ray emitters. So far 9 {\gamma}-ray GCs have been identified and a few candidates such as 2MS-GC01 and IC 1257 have been suggested. In this work, after analyzing the publicly-available Fermi-LAT data we confirm the significant {\gamma}-ray emission from 2MS-GC01 and IC 1257 and report the discovery for {\gamma}-ray emission from NGC 5904 and NGC 6656 within their tidal radii. Also a strong evidence of significant {\gamma}-ray emission is found from FSR 1735. From the observed {\gamma}-ray luminosities, the numbers of MSPs that are expected to be present in these GCs are estimated.