Details

Autor(en) / Beteiligte

• Zdziarski, Andrzej A
• Malyshev, Denys
• de Oña Wilhelmi, Emma
• Pedaletti, Giovanna
• Yang, Ruizhi
• Chernyakova, Maria
• López-Caniego, Marcos
• Mikołajewska, Joanna
• Basak, Rupal

Titel

The high-energy gamma-ray detection of G73.9+0.9, a supernova remnant interacting with a molecular cloud

Ist Teil von

• Monthly notices of the Royal Astronomical Society, 2016-01, Vol.455 (2), p.1451-1458

Ort / Verlag

London: Oxford University Press

Erscheinungsjahr

2016

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We have analysed the Fermi Large Area Telescope (LAT) data on the SNR G73.9+0.9. We have confirmed a previous detection of high-energy γ-rays from this source at a high significance of ≃12σ. The observed spectrum shows a significant curvature, peaking in EFE at ∼1 GeV. We have also calculated the flux upper limits in the mm-wavelength and X-ray ranges from Planck and XMM–Newton, respectively. We have inspected the intensity of the CO (1→0) emission line and found a large peak at a velocity range corresponding to the previously estimated source distance of ∼4 kpc, which may indicate an association between a molecular cloud and the supernova remnant (SNR). The γ-ray emission appears due to interaction of accelerated particles within the SNR with the matter of the cloud. The most likely radiative process responsible for the γ-ray emission is decay of neutral pions produced in ion–ion collisions. While a dominant leptonic origin of this emission can be ruled out, the relativistic electron population related to the observed radio flux will necessarily lead to a certain level of bremsstrahlung γ-ray emission. Based on this broad-band modelling, we have developed a method to estimate the magnetic field, yielding B ≳ 80 μG at our best estimate of the molecular cloud density (or less at a lower density). G73.9+0.9 appears similar, though somewhat weaker, to other SNRs interacting with a local dense medium detected by the LAT.