Asiago spectroscopic classification of 2 SNe and one AGN.
ATel #9417; G. Terreran (INAF OAPd, QUB), M. Berton (DFA UniPd), S. Benetti, E. Cappellaro, N. Elias-Rosa, P. Ochner, A. Pastorello, L. Tomasella, M. Turatto (INAF OAPd)
on 26 Aug 2016; 16:22 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: N. Elias-Rosa (firstname.lastname@example.org)
Subjects: Optical, Supernovae
Referred to by ATel #: 9843
The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classification of ASASSN-16ji (AT 2016fio) in GALEXASC J201155.52+811602.0, PS16dtm (SN 2016ezh) in SDSS J233345.91+253350.7, and Gaia16bbt (SN 2016fee; anonymous host galaxy).
The targets are supplied by the All Sky Automated Survey for SuperNovae (ASAS-SN), the Gaia Photometric Science Alerts programme and the Pan-STARRS Survey for Transients (PSST, see Huber et al. ATel #7153)
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 | IAU Name | Discovery (UT) | Discovery mag | Observation (UT) | Redshift | Type | Phase | Notes
ASASSN-16ji | AT 2016fio | 2016-08-25 | 17.1 | 2016-08-25.98 | 0.080 | AGN | - | (1)
PS16dtm | SN 2016ezh | 2016-08-12 | 17.0 | 2016-08-26.02 | 0.080 | SN II | 1 month | (2)
Gaia16bbt | SN 2016fee | 2016-08-18 | 18.6 | 2016-08-26.10 | 0.032 | SN II | 1 week | (3)
(1) The redshift is measured from the position of the maximum of [O III] line at 5007A. Hbeta shows a FWHM of ~1500km/s, which is compatible with the characteristics of a Narrow-Line Seyfert 1 galaxy. Following Berton et al. 2015, A&A, 578, 28, we infer a black hole mass of ~10^7 Msun. The target might be associated with the X-ray source 1RXS J201154.6+811600.
(2) The spectrum looks similar to those of SN 1996al (Benetti et al 2016, MNRAS 456, 3296) with phases close to one month after maximum light, although several differences are also visible. The redshift has been measured from a narrow emission superimposed to the broad Halpha.
(3) Already observed on 2016-08-23.08: the previous spectrum showed a blue, featureless continuum (Atel #9397).
This new spectrum clearly shows a broad Halpha and we can classify it as a Type II SN soon after explosion, with
the best match being with SN 1999gi (Smartt et al. 2001, ApJ 556L, 25S) at phase around 1 week.
From the position of the minimum of the Halpha feature, we infer an expansion velocity of 13500km/s for the ejected material. The redshift has been measured from a narrow emission superimposed to the broad Halpha.
The classifications were performed using the GELATO (Harutyunyan et al. 2008, A&A, 488, 383) and SNID (Blondin and Tonry 2007, ApJ, 666, 1024) tools.
The Asiago classification spectra are posted at the website http://sngroup.oapd.inaf.it.