The supernova remnant G46.8–0.3 and its interaction with the ambient matter, a plausible counterpart to the GeV gamma rays in the region

FISCHETTO G.; SUPAN L.; CASTELLETTI G.

Congreso; 63a Reunión Anual de la Asociación Argentina de Astronomía; 2021

Observatorio Astronómico de Córdoba

We analysed the continuum radiation at radio wavelengths from the supernova remnant (SNR) G46.8–0.3, along with the emission in the CO(1-0) rotational and HI 21 cm lines from the ambient medium. The investigation revealed a large low-density cavity in HI formed by the joint action of the SNR shock and the activity of the G46.8–0.3’s progenitor star. On the basis of the distribution of the atomic gas and its spectral properties, we revisited the distance to the source and proposed it is an evolved remnant in the Galaxy. In addition, in the observed CO gas morphology and kinematics we found evidence for the interaction between the supernova shock and the surrounding clouds. The physical association of G46.8–0.3 with the dense local medium could explain the origin of the Fermi gamma ray source 4FGL J1918.1+1215 detected in direction to the remnant.