GMRT radio constraints on the mass-loss rate of the type Ia SN 2020rcq
ATel #13995; Poonam Chandra (NCRA-TIFR), Peter Lundqvist (Stockholm University), Miguel Perez-Torres (IAA-CSIC)
on 8 Sep 2020; 10:41 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Poonam Chandra (poonam@ncra.tifr.res.in)
Subjects: Radio, Supernovae, Transient
We report the non-detection at radio wavelengths of the type Ia SN2020rcq, discovered on 2020-08-09 04:01:29.280 at the position (J2000.0) RA = 11:57:14.680 DEC = +49:17:32.00 in UGC 06930 (2020TNSTR2455), at a distance of 11 Mpc, and classified as a Type Ia SN (2020TNSAN.152).
We observed SN 2020rcq with the upgraded Giant Metrewave Radio Telescope (uGMRT), India on 2020 Aug 29.24 UT, at a central frequency of 1.255 GHz, with a bandwidth of ~280 MHz. The final image has a resolution of 2.91 arcsec by 1.61 arcsec at a position angle of 62.45 degrees. We find no evidence of radio emission from SN 2020rcq above a 3-sigma upper limit of 58.9 microJy/beam in the region surrounding the optical position of the SN. Our observations are not contaminated by the galaxy background emission at the position of SN 2020rcq. Our flux density upper limit
corresponds to a 3-sigma upper limit to the monochromatic luminosity of 8.6E24
erg/s/Hz. In turn, this upper limit of the luminosity sets a stringent constraint on the
mass-loss rate of the progenitor star of 1.0E-8 Msun/yr (3-sigma), for an assumed wind
speed of 100 km/s and t=21 days after the explosion, and the model used in ATel #13937.
We thank the staff of the GMRT that made these observations possible.
