Origin of the gamma-ray emission from supernova remnant HB9

Abstract

HB9 (G160.9+2.6) is a mixed-morphology Galactic supernova remnant (SNR) at a distance of $\sim$0.6 kpc. Previous analyses revealed recombining plasma emission in X-rays and an expanding shell structure in HI and CO emission, which were correlating with the spatial extent of HB9. In GeV energies, HB9 was found to show extended gamma-ray emission with a morphology that is consistent with the radio continuum emission showing a log-parabola-type spectrum. The overlap reported between the gas data and the excess gamma-ray emission at the southern region of the SNR's shell could indicate a possible interaction between them. We searched for hadronic gamma-ray emission signature in the spectrum to uncover possible interaction between the molecular environment and the SNR. Here we report the results of the gamma-ray spectral modelling studies of HB9.

Presented as a poster at the 43rd COSPAR Scientific Assembly, 28 January - 4 February 2021, Sydney, Australia