GMRT observations of four suspected supernova remnants near the Galactic Centre

We have observed two fields Field I (l=3.2◦, b=−1.0◦) and Field II (l=356.8◦, b=−0.1◦) with the Giant Metrewave Radio Telescope (GMRT) at 330 MHz. In the first field, we have studied the candidate supernova remnant (SNR) G3.1−0.6 and based on its observed morphology, spectral index and polarisation confirmed it to be an SNR. We find this supernova to have a double ring appearance with a strip of emission on it’s western side passing through it’s centre. We have discovered two extended curved objects in the second field, which appears to be part of a large shell like structure. It is possibly the remains of an old supernova in the region. Three suspected supernova remnants, G356.3−0.3, G356.6+0.1 and G357.1−0.2 detected in the MOST 843 MHz survey of the Galactic Centre region appears to be located on this shell like structure. While both G356.3−0.3 and G356.6+0.1 seem to be parts of this shell, G357.1−0.2 which has a steeper spectrum above 1 GHz, could be a background SNR seen through the region. Our HI absorption observation towards the candidate SNR G357.1−0.2 indicates that it is at a distance of more than 6 kpc from us.