ePESSTO spectroscopic classification of optical transients
ATel #11485; C. Vogl (MPA), A. Floers, S. Taubenberger (ESO), S. Benetti, A. Pastorello (INAF-Padova Observatory), L. Galbany (Pittsburgh), C. Gall (DARK, KU), J. Lyman (Warwick), C. Inserra (Southampton), E. Kankare (QUB), K. Maguire, S. J. Smartt (QUB), D. R. Young (QUB), O. Yaron (Weizmann)
on 28 Mar 2018; 15:20 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Andrea Pastorello (andrea.pastorello@oapd.inaf.it)
Subjects: Optical, Supernovae, Transient
ePESSTO, the extended Public ESO Spectroscopic Survey for Transient Objects (see Smartt et al. 2015, A&A, 579, 40; http://www.pessto.org ), reports the following supernova classifications. Targets were supplied by the All Sky Automated Survey for SuperNovae (ASAS-SN; see Shappee et al. 2014, ApJ, 788, 48 and http://www.astronomy.ohio-state.edu/~assassin/index.shtml ) and the ESA Gaia Photometric Science Alerts Team and DPAC (http://gsaweb.ast.cam.ac.uk/alerts).
All observations were performed on the ESO New Technology Telescope at La Silla on 2018 March 28 UT, using EFOSC2 and Grism 13 (3985-9315A, 18A resolution). Classifications were done with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024) and GELATO (Harutyunyan et al., 2008, A&A, 488, 383). Classification spectra and additional details can be obtained from http://www.pessto.org (via WISeREP) and the IAU Transient Name Server.
Survey Name | IAU Name | RA (J2000) | Dec (J2000) | Disc. Date | Source | Discovery Mag. | z | Type | Phase | Notes
ASASSN-18fn | SN 2018ais | 11 38 47.05 | -33 10 02.57 | 2018 03 17.93 | ASAS-SN | 17.4 (g-Sloan) | 0.035658 | Ia | +12d from max | (1)
Gaia18arr | SN 2018akm | 18 07 44.90 | +18 44 59.39 | 2018 03 21.56 | Gaia | 18.46 (G-Gaia) | 0.078 | Ia-pec | +10d from max | (2)
(1) The spectrum matches that of a normal SN Ia about 12 days after the B-band maximum. The SN ejecta velocity, deduced from the wavelength of the
Si II 635.5 nm minimum, is about 10800 km/s. The redshift of the host galaxy 2MASX J11384720-3310063 is from Huchra et al. 2012, ApJS, 199, 26.
(2) The spectrum resembles that of a 1991T-like SN Ia about 10 days after the B-band light curve peak. The ejecta velocity, inferred from the wavelength
of the Si II 635.5 nm minimum, is about 9400 km/s. The redshift of the host galaxy is obtained from the broad SN features.
