Spectroscopic classification of the rebrightening of SNhunt151 in NGC 3165
ATel #5358; A. Pastorello (INAF-Osservatorio Astronomico di Padova), A. Harutyunyan (Telescopio Nazionale Galileo) F. Ciabattari, E. Mazzoni (Borgo a Mozzano, Italy), S. Benetti, E. Cappellaro, P. Ochner, L. Tartaglia, L. Tomasella, M. Turatto (INAF-Osservatorio Astronomico di Padova), N. Elias-Rosa, A. Moralez-Garoffolo (ICE-IEEC/CSIC Barcelona), S. Valenti, M. L. Graham, D. A. Howell (Las Cumbres Observatory Global Telescope and University of California at Santa Barbara), S. Leonini, G. Guerrini, P. Rosi, L. M. Tinjaca Ramirez (Siena, Italy)
on 3 Sep 2013; 16:36 UT
Credential Certification: Enrico Cappellaro (firstname.lastname@example.org)
Subjects: Supernovae, Transient
Recent photometry obtained with the Asiago Telescopes, the Las Cumbers Observatory Global telescope network (LCOGT) facilities and the Liverpool telescopes reveals that the transient SNhunt151 in NGC 3165 discovered by the Catalina Real Time Transient Survey (http://nesssi.cacr.caltech.edu/catalina/current.html) has significantly brightened (r=17.6 on Aug 30.17 UT). The object has been also detected in a number of past images of the Italian Supernova Search Program (ISSP;http://italiansupernovae.org/index.php) obtained since October 2012 with the 0.53m telescope of the Astronomical Observatory of Montarrenti (Siena) and the 0.5m Newton telescope of the Astronomical Observatory of Monte Agliale (Lucca).
Here we report that an optical spectrogram of SNhunt151 has been obtained on Sep 02.21 UT with the 3.54-m Telescopio Nazionale Galileo (+ LRS; range 335-800 nm; resolution 1.2 nm). The spectrum is dominated by prominent H lines of the Balmer series, with asymmetric profiles. Resolved narrow emission components (with FWHM velocity of about 800 km/s) are superimposed on broad P-Cygni H features. The absorptions indicate a velocity of about 6000 km/s for the bulk of the material, but with blue wings extending up to 13000 km/s. Narrow Fe II lines are also detected, with a velocity comparable with that of the narrow H line components.
The overall spectroscopic and photometric behavior resembles that of SN 2009ip (Pastorello et al. 2013, ApJ, 767, 1; Fraser et al. 2013, MNRAS, 433, 1312) whose nature (real type IIn SN or SN impostor) is still debated (see e.g. Margutti et al. 2013, eprint arXiv:1306.0038).