Asiago spectroscopic classification of two SNe

ATel #6906; L. Tomasella, S. Benetti, E. Cappellaro, N. Elias-Rosa, P. Ochner, A. Pastorello, L. Tartaglia, G. Terreran, M. Turatto (INAF OAPd)
on 13 Jan 2015; 11:27 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Enrico Cappellaro (enrico.cappellaro@oapd.inaf.it)

Tweet

The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic observation of PSN J06574303+1334457 in UGC 3617 and PSN J13183047-1436446 in IC 4221. Targets were supplied by the Astronomy Section of the Rochester Academy of Sciences (arXiv:1103.5165) and by the CBAT Transient Objects Confirmation Page (TOCP). The observations were performed with the Asiago 1.82m Copernico Telescope (+AFOSC; range 340-820 nm; resolution 1.2 nm) equipped with the CCD Andor IKON L936.

  
 
Name                   | Date (UT)   |  z      |   Type    | Phase  | Notes 
PSN J06574303+1334457  | 20150112.99 |  0.013  |  SN II    | +10d   | (1)   
PSN J13183047-1436446  | 20150113.16 |  0.009  |  SN II    |  3w    | (2)   

(1) Best match with type-II SNe about two weeks after explosion. Bluewards to the H-alpha emission, there are two distinct absorptions. Assuming they are both due to H-alpha (at regular and high velocity) and adopting a recessional velocity of 3984 km/s for the host galaxy UGC 3617 (HIPASS HI Parkes All Sky Survey 2006; via NED), the inferred expansion velocities for the two components are 11800 km/s and 18700 km/s, respectively. Since H-beta shows only a single PCygni absorption, blue-shifted by about 11100 km/s, the bluer absorption near H-alpha can be most likely attributed to SiII-635.5nm, for which an expansion velocity of about 9800 km/s is derived.

(2) Best match with type-II SNe around 3-4 weeks after explosion. Host galaxy IC 4221 redshift from Catinella et al. 2005 (AJ 130, 1037, via NED).

Classification was done with GELATO (Harutyunyan et al. 2008, A&A, 488, 383) and SNID (Blondin and Tonry 2007, ApJ, 666, 1024). The Asiago classification spectra are posted at the website http://sngroup.oapd.inaf.it.