SALT spectroscopic classification of PS15bqc as a type-IIb SN before maximum light
ATel #7901; S. W. Jha (Rutgers), Y.-C. Pan, R. J. Foley (Illinois), A. Rest (STScI), D. Scolnic (Chicago/KICP), K. W. Smith, D. Wright, S. J. Smartt (QUB), M. Huber, K. C. Chambers, H. Flewelling, M. Willman, N. Primak, A. Schultz, B. Gibson, E. Magnier, C. Waters, J. Tonry, R. J. Wainscoat (IfA, Hawaii), B. Miszalski (SALT/SAAO)
on 11 Aug 2015; 04:19 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Saurabh Jha (saurabh@physics.rutgers.edu)
Subjects: Optical, Supernovae
We obtained SALT (+RSS) spectroscopy of PS15bqc on 2015 Aug 10.8 UT,
covering the wavelength range 340-920 nm. Cross-correlation of the
spectrum with a template library using SNID (Blondin & Tonry 2007,
ApJ, 666, 1024) shows PS15bqc is likely a type-IIb supernova a few days
before maximum light, with good matches to spectra of SN 1993J at -3
or -2 days from maximum. Other matches with spectra of SN IIP a few weeks
past maximum are plausible, but less convincing, and the rising light
curve favors the pre-maximum classification.
Strong, narrow emission lines superimposed on the SN spectrum yield a
redshift z = 0.023, matching the host galaxy CGCG 029-015 (Marzke,
Huchra, & Geller 1996, AJ, 112, 1803). The expansion velocity measured
to the trough of the P-Cygni H-alpha profile is 10,200 km/s.
PS15bqc was discovered as part of the Pan-STARRS Survey for Transients
(Huber et al. 2015, ATel #7153). Information on all PSST objects is
available at http://star.pst.qub.ac.uk/ps1threepi/