[ Previous | Next | ADS ]

Asiago spectroscopic classification of three transients

ATel #11082; L. Tomasella, S. Benetti, E. Cappellaro, M. Turatto
on 22 Dec 2017; 10:02 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Stefano Benetti (stefano.benetti@oapd.inaf.it)

Subjects: Optical, Supernovae, Variables

The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classification of AT 2017jbj discovered by K.Itagaki in NGC 0259, AT 2017jbl discovered by R. Gagliano, R. Post, E. Weinberg, Jack Newton, and Tim Puckett in UGC 2780, and PS17fjk (AT 2017jco).

The observations were performed with the Asiago 1.82 m Copernico Telescope equipped with AFOSC (range 340-820 nm; resolution 1.4 nm).

 
 
Survey Name   | IAI Name      | Discovery date (UT)  | Discovery mag | Observation (UT)    |  Type  | z         | Notes| 
AT 2017jbj    | SN 2017jbj    | 2017-12-20 11:56:20  |   16.9        |2017-12-21 20:15:00  |   CC   |  0.013492 | (1)  |  
AT 2017jbl    | SN 2017jbl    | 2017-12-20 23:42:50  |   18.3        |2017-12-21 23:13:00  |   II   |  0.015054 | (2)  |  
PS17fjk       | AT 2017jco    | 2017-12-08 12:31:40  | i-Sloan=15.6  |2017-12-22 02:05:00  |   CV   |  Galactic | (3)  | 
 
 

(1) The spectrum shows an almost featureless, blue continuum, typically seen in young core collapse SNe a few days after explosion. The redshift was reported in the HI Parkes All Sky Survey Final Catalog (2006). Assuming this redshift, the blackbody temperature of the continuum is about 15000/20000 K.

(2) Spectrum consistent with those of Type IIb supernovae 1993J and 2011fu past maximum. If the above listed redshift is assumed (Haynes et al. 1993, AJ 105, via NED), an expansion velocity of about 14000 km/s is derived from the H-alpha absorption.

(3) The spectrum shows a blue continuum with absorption features of the Balmer series and HeII lines at rest wavelength.

Classifications were 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.