Radio detection of the hydrogen-poor super-luminous supernova 2020tcw at 64 days post discovery
ATel #14418; Deanne L. Coppejans, David Matthews, Raffaella Margutti, Giacomo Terreran, Wynn Jacobson-Galan (Northwestern U.), Edo Berger, Tarraneh Eftekhari (Harvard U.), Michael Bietenholz (SARAO/Hartrao and York U.), Danny Milisavljevic (Purdue U.), Tanmoy Laskar (U. Bath), Conor Omand (U. Tokyo), Matt Nicholl (U. Birmingham)
on 22 Feb 2021; 17:08 UT
Credential Certification: Deanne Coppejans (deanne.coppejans@gmail.com)
Subjects: Radio, Supernovae, Transient
We report the first radio detection of the supernova (SN) 2020tcw. This is the third hydrogen-poor super-luminous supernova detected at radio wavelengths (iPTF10hgi and SN 2017ens were detected previously, see Eftekhari et al. 2019 and ATel #14393). SN 2020tcw was discovered on 12 September 2020 (TNS Astronomical Transient Report No. 81951) and classified as a hydrogen-poor super-luminous supernova (AstroNote 2020-192). We observed SN 2020tcw 64 days post discovery with the NSF's Karl G. Jansky Very Large Array (VLA) with program VLA/20B-144 (PI: D. Matthews). We detected a radio point source within one synthesized beamwidth of the optical position. Here we report the preliminary flux density:
Name | Date (UT) | Mean Obs Freq (GHz) | Bandwidth (GHz) | Flux density (mJy) | Uncertainty (mJy) | RA | Dec
SN 2020tcw | 15 November 2020, 20:39:01 | 6.0 | 4.096 | 0.2 | 0.02 | 15:28:17.17 | +39:56:50.38
The emission at radio wavelengths may be powered by the interaction of the blastwave with a dense circumstellar environment. This scenario would be in agreement with the recent flattening (and possible rebrightening) of the optical light curves (r- and g-band) from the Zwicky Transient Facility (Kulkarni 2018; ATel #11266). Further observations are encouraged.
We thank the VLA for scheduling these observations. We are conducting further radio follow-up observations.
