ePESSTO spectroscopic classification of optical transients

ATel #11480; A. Floers, S. Taubenberger (ESO), C. Vogl (MPA), 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), O. Yaron (Weizmann), D. R. Young (QUB), J. Tonry, L. Denneau, A. Heinze, H. Weiland (IfA, Univ. of Hawaii), B. Stalder (LSST), A. Rest (STScI), K. W. Smith, O. McBrien (QUB), D. E. Wright (Univ. of Minnessota), K. C. Chambers, H. Flewelling, M. Huber, T. Lowe, E. Magnier, A. Schultz, C. Waters, R. J. Wainscoat, M. Wilman (IfA, Univ. of Hawaii)
on 27 Mar 2018; 14:00 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Andrea Pastorello (andrea.pastorello@oapd.inaf.it)

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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 ATLAS survey, see Tonry et al. (2011, PASP, 123, 58) and Tonry et al. (ATel #8680), the ESA Gaia Photometric Science Alerts Team and DPAC (http://gsaweb.ast.cam.ac.uk/alerts), 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 Pan-STAR RS Survey for Transients (see Chambers et al. 2016, arXiv:1612.05560, and http://pswww.ifa.hawaii.edu ).
All observations were performed on the ESO New Technology Telescope at La Silla on 2018 March 27 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 
ATLAS18mrr    | SN 2018amd | 11 45 41.48 | -07 29 11.54 | 2018 03 19.50  | ATLAS             | 18.91 (o-ATLAS) | 0.050692 | II    | 13d after expl.  | (1) 
ATLAS18mfr    | SN 2018ame | 15 09 25.52 | +25 28 17.56 | 2018 02 28.64  | ATLAS             | 17.60 (o-ATLAS) | 0.022065 | Ia-pec| +19d from max    | (2) 
Gaia18aqr     | AT 2018aja | 14 22 50.52 | -22 18 28.91 | 2018 03 16.36  | Gaia              | 16.84 (G-Gaia)  | Galactic | CV    | early            | (3) 
ASASSN-18gk   | SN 2018amp | 13 37 36.28 | -31 57 52.16 | 2018 03 25.96  | ASAS-SN           | 17.1 (g-Sloan)  | 0.047    | Ia-pec| +13d from max    | (4) 
Gaia18ark     | SN 2018akb | 15 47 36.04 | -10 27 38.59 | 2018 03 19.92  | Gaia	             | 18.0 (G-Gaia)   | 0.040    | Ia    | at max           | (5) 
PS18na        | SN 2018alh | 13 25 49.07 | -07 06 28.06 | 2018 03 20.44  | PS1               | 19.95 (r-Sloan) | 0.063310 | Ia    | -3d from max     | (6) 
MAXI J1820+070| AT 2018amn | 18 20 21.93 | +07 11 07.22 | 2018 03 24.07  | MAXI/GSG, ASAS-SN | 12.0 (G-Gaia)   | Galactic | XRB   |                  | (7) 
  
(1) Low S/N spectrum, Type II SN ~2 weeks after the explosion, with broad P Cygni lines of H, Fe II and Na ID (or He I 587.6). The host galaxy 2MASX J11454058-0729331  
redshift is from 6dF GSDR3 (Jones et al. 2009). 
 
(2) Spectrum of a peculiar 1991bg-like SN Ia about 3 weeks after maximum. The host galaxy SDSS J150925.64+252815.2 redhift is from SDSS DR13. 
 
(3) The spectrum shows a blue, almost featureless continuum. A narrow Halpha in emission suggests a Galactic CV classification. 
 
(4) The spectrum matches that of the peculiar ("Super-Chandrasekhar" mass) Type Ia SN 2009dc (Taubenberger et al. 2011, MNRAS, 412, 2735) ~3 weeks after max. The ejecta  
velocity, from the position of the Si II 635.5 nm minimum, is 6500 km/s. The redshift is estimated from the SN spectrum. 
 
(5) Spectrum of a normal Type Ia SN around the maximum light. The ejecta velocity, from the minimum of the Si II 635.5 nm line, is 10400 km/s. The redshift is obtained  
from the broad SN features. 
 
(6) Spectrum of a normal SN Ia a few days before maximum. The ejecta velocity, from the wavelength of the Si II 635.5 nm minimum, is ~12000 km/s. The redshift of the host  
galaxy is from the 6dF GSDR 3 (Jones et al. 2009). 
 
(7) ePESSTO observed the X-ray binary in outburst (and black hole candidate) MAXI J1820+070 (aka ASASSN-18ey, aka Gaia18as; ATel#11399, ATel#11400). Our spectrum, with  
a very blue continuum, shows H, N III 464.1, He II 468.6 and (weaker) He I lines in pure emission, and agrees with earlier descriptions in ATel #11424 and ATel #11425.