Probing the star formation origin of gamma-rays from 3FHL J1907.0+0713


Ergin T., Saha L., Bhattacharjee P., Sano H., Tanaka S. J. , Majumdar P., ...More

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, vol.501, no.3, pp.4226-4237, 2021 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 501 Issue: 3
  • Publication Date: 2021
  • Doi Number: 10.1093/mnras/staa3817
  • Title of Journal : MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
  • Page Numbers: pp.4226-4237
  • Keywords: pulsars: individual: PSR J1906+0722, stars: winds, outflows, ISM: individual objects: 3FHL J1907.0+0713 (4FGL J1906.9+0712), ISM: individual objects: 3C 397 (G41.1-0.3), gamma-rays: ISM, submillimetre: ISM, X-RAY, FORMING REGIONS, GALACTIC PLANE, EMISSION, FERMI, PROGENITOR, CATALOG, RADIO

Abstract

Star-forming (SF) regions embedded inside giant molecular clouds (GMCs) are potential contributors to Galactic gamma-rays. The gamma-ray source 3FHL J1907.0+0713 is detected with a significance of roughly 13 sigma in the 0.2-300 GeV energy range after the removal of gamma-ray pulsation periods of PSR J1906+0722 from the Fermi-LAT data set of about 10 yr. The energy spectrum of 3FHL J1907.0+0713 is best-fitted to a power-law model with a spectral index of 2.26 +/- 0.05. The CO(J = 1-0) data taken by NANTEN2 revealed that 3FHL J1907.0+0713 is overlapping with a GMC having a peak velocity of about 38 km s -1. The best-fitting location of 3FHL J1907.0+0713 is measured to be approximately 0.13 deg away from the Galactic supernova remnant (SNR) 3C 397 and it overlaps with a star that is associated with a bow-shock nebula. We show that there is no physical connection between 3FHL J1907.0+0713, 3C 397, as well as any positional coincidence with the pulsar. The spectrum of 3FHL J1907.0+0713 is fitting to both hadronic and leptonic gamma-ray emission models and the total luminosity at a distance of 2.6 kpc is calculated to be 1.1 x 10(34) erg s(-1). We also discuss possible SF origins of gamma-rays from 3FHL J1907.0+0713, where SNRs, massive protostar outflows, stellar winds from runaway stars, colliding wind binaries, and young stellar clusters are considered as candidate sources.