Discovery of the supernova remnant G351.0-5.4

Abstract

Context. While searching the NRAO VLA Sky Survey (NVSS) for diffuse radio emission, we have serendipitously discovered extended radio emission close to the Galactic plane. The radio morphology suggests the presence of a previously unknown Galactic supernova remnant. An unclassified γ-ray source detected by EGRET (3EG J1744-3934) is present in the same location and may stem from the interaction between high-speed particles escaping the remnant and the surrounding interstellar medium. Aims. Our aim is to confirm the presence of a previously unknown supernova remnant and to determine a possible association with the γ-ray emission 3EG J1744-3934. Methods. We have conducted optical and radio follow-ups of the target using the Dark Energy Camera (DECam) on the Blanco telescope at Cerro Tololo Inter-American Observatory (CTIO) and the Giant Meterwave Radio Telescope (GMRT). We then combined these data with archival radio and γ-ray observations. Results. While we detected the extended emission in four different radio bands (325, 1400, 2417, and 4850 MHz), no optical counterpart has been identified. Given its morphology and brightness, it is likely that the radio emission is caused by an old supernova remnant no longer visible in the optical band. Although an unclassified EGRET source is co-located with the supernova remnant, Fermi-LAT data do not show a significant γ-ray excess that is correlated with the radio emission. However, in the radial distribution of the γ-ray events, a spatially extended feature is related with SNR at a confidence level $\sim 1.5$ σ. Conclusions. We classify the newly discovered extended emission in the radio band as the old remnant of a previously unknown Galactic supernova: SNR G351.0-5.4.

arXiv comment6 pages, 6 figures, accepted A&A

References in corpus (12)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• Fermi Large Area Telescope Second Source Catalog
• Detection of the Characteristic Pion-Decay Signature in Supernova Remnants
• Clusters of galaxies : observational properties of the diffuse radio emission
• The Fermi Large Area Telescope On Orbit: Event Classification, Instrument Response Functions, and Calibration
• A morphological algorithm for improving radio-frequency interference detection
• The Parkes Multibeam Pulsar Survey: V. Finding binary and millisecond pulsars
• Direct Evidence for Hadronic Cosmic-Ray Acceleration in the Supernova Renmant IC 443
• AGILE detection of GeV gamma-ray emission from the SNR W28
• The Supernova Remnant W44: confirmations and challenges for cosmic-ray acceleration
• Fermi-LAT Observation of Supernova Remnant S147

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