Spectroscopic classification of AT 2018adg as a Type Ic supernova
ATel #11397; S. C. Williams (Lancaster), J. Nordin (Humboldt Berlin), I. M. Hook (Lancaster)
on 11 Mar 2018; 10:11 UT
Credential Certification: Steven Williams (scw@astro.ljmu.ac.uk)
Subjects: Optical, Supernovae, Transient
We obtained a spectrum of the transient AT 2018adg (see TNS) with the SPRAT spectrograph (resolution R ~ 350; Piascik et al. 2014) on the 2-m Liverpool Telescope (LT; Steele et al. 2004) on 2018 Mar 11.13 UT.
The spectrum is consistent with AT 2018adg being a Type Ic supernova around peak brightness, at a redshift of z ~ 0.02 to 0.03, in agreement with the host galaxy redshift of z = 0.022 (da Costa et al. 1998). Comparing the spectrum to templates via SNID (Blondin & Tonry 2007) shows good matches to the Type Ic supernovae SN 2004aw and SN 1994I around peak brightness. We note however that a possible match (although significantly poorer than the Ic templates) can also be obtained for the peculiar Type Ia supernova SN 2005hk.
The host galaxy of AT 2018adg is part of C17 of the K2 mission, therefore further follow-up is strongly encouraged.
