G279.0+1.1: a new extended source of high-energy gamma rays

Abstract

G279.0+1.1 is a supernova remnant (SNR) with poorly known parameters, first detected as a dim radio source and classified as an evolved system. An analysis of data from the Fermi-LAT revealing for the first time an extended source of gamma rays in the region is presented. The diameter of the GeV region found is ~2.8${}^{\circ }$, larger than the latest estimate of the SNR size from radio data. The gamma-ray emission covers most of the known shell and extends further to the north and east of the bulk of the radio emission. The photon spectrum in the 0.5--500 GeV range can be described by a simple power law, $\frac{dN}{dE}\propto E^{-\Gamma }$, with a spectral index of $\Gamma =1.86\pm 0.03_{stat}\pm 0.06_{sys}$. In the leptonic scenario, a steep particle spectrum is required and a distance lower than the previously estimated value of 3 kpc is favored. The possibility that the high-energy emission results from electrons that already escaped the SNR is also investigated. A hadronic scenario for the gamma rays yields a particle spectral index of $\sim 2.0$ and no significant constraints on the distance. The production of gamma rays in old SNRs is discussed. More observations of this source are encouraged to probe the true extent of the shell and its age.

arXiv comment8 pages, 4 figures. Accepted for publication in MNRAS

References in corpus (34)

• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• The ATNF Pulsar Catalogue
• The ATNF Pulsar Catalogue
• Fermi Large Area Telescope First Source Catalog
• Cosmic-ray propagation and interactions in the Galaxy
• Detection of the Characteristic Pion-Decay Signature in Supernova Remnants
• SUMSS: A Wide-Field Radio Imaging Survey of the Southern Sky. II. The Source Catalogue
• The 70 Month Swift-BAT All-Sky Hard X-Ray Survey
• The Origin of Galactic Cosmic Rays
• The Fermi Large Area Telescope On Orbit: Event Classification, Instrument Response Functions, and Calibration
• The H.E.S.S. Galactic plane survey
• The WISE Catalog of Galactic HII Regions
• 3FHL: The Third Catalog of Hard Fermi-LAT Sources
• The 1st Fermi Lat Supernova Remnant Catalog
• Search for extended sources in the Galactic Plane using 6 years of Fermi-Large Area Telescope Pass 8 data above 10 GeV
• The theory of synchrotron emission from supernova remnants
• A New 1.4GHz Radio Continuum Map of the Sky South of Declination +25 deg
• Population study of Galactic supernova remnants at very high $\gamma$-ray energies with H.E.S.S.
• Escape of cosmic-ray electrons from supernova remnants
• Exploring particle escape in supernova remnants through gamma rays
• Unified model for the gamma-ray emission of supernova remnants
• Supernova remnants in clumpy media: particle propagation and gamma-ray emission
• A search for new supernova remnant shells in the Galactic plane with H.E.S.S
• On the radio spectra of supernova remnants
• Evidence for Cosmic Ray Acceleration in Cassiopeia A
• The Search for Faint Radio Supernova Remnants in the Outer Galaxy: Five New Discoveries
• Detailed spectral and morphological analysis of the shell type SNR RCW 86
• Time Evolution of Gamma Rays from Supernova Remnants
• First detection of optical light from SNR G279.0+1.1
• Time evolution of broadband non-thermal emission from supernova remnants in different circumstellar environments
• Detection of GeV Gamma-rays from HESS J1534-571 and Multiwavelength Implications for the Origin of the Non-thermal Emission
• Polarised radio emission associated with HESS J1912+101
• Discovery of an extended source of gamma-ray emission in the Southern Hemisphere
• X-Ray and Gamma-Ray Emission from Middle-aged Supernova Remnants in Cavities. I. Spherical Symmetry

Cited by in corpus (7)

• Incremental Fermi Large Area Telescope Fourth Source Catalog
• TeV cosmic ray nuclei acceleration in shell-type supernova remnants with hard $\gamma$-ray spectra
• G17.8+16.7: A New Supernova Remnant
• Fermi-LAT detection of G118.4+37.0: a supernova remnant in the Galactic halo seen around the Calvera pulsar
• X-ray counterpart detection and gamma-ray analysis of the SNR G279.0+01.1 with eROSITA and Fermi-LAT
• Non-thermal GeV emission from the Nereides nebula: confirming the nature of the supernova remnant G107.7-5.1
• GeV emission in the region of Vela: a new view of the supernova remnant