ePESSTO spectroscopic classification of optical transients
ATel #12265; M. Pursiainen (Southampton), N. Castro-Segura (Southampton), C. P. Gutierrez (Southampton), T. Muller (Southampton), T.-W. Chen (MPE), J. Anderson (ESO), C. Inserra (Cardiff), E. Kankare (QUB), K. Maguire (QUB), S. J. Smartt (QUB), D. R. Young (QUB), O. Yaron (Weizmann), I. Manulis (Weizmann), J. Tonry (IfA, Univ. of Hawaii), L. Denneau (IfA, Univ. of Hawaii), A. Heinze (IfA, Univ. of Hawaii), H. Weiland (IfA, Univ. of Hawaii), B. Stalder (LSST), A. Rest (STScI), K. W. Smith (QUB), O. McBrien (QUB), D. E. Wright (Univ. of Minnesota), L. Wyrzykowski (Warsaw Observatory, Poland), S. Taubenberger (MPA-Garching), S. Benetti (Padova), A. Pastorello (Padova), M. Gromadzki (Warsaw)
on 4 Dec 2018; 19:38 UT
Credential Certification: Claudia Gutierrez (c.p.gutierrez-avendano@soton.ac.uk)
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 ATLAS survey (see Tonry et al., 2011, PASP, 123, 58), and OGLE-IV Real-time Transient Search (Wyrzykowski et al., 2014 arxiv:1409.1095; http://ogle.astrouw.edu.pl/ ). All observations were performed on the ESO New Technology Telescope at La Silla on 2018 December 3, 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 | Disc Mag | z | Type | Phase | Notes
ATLAS18zps | SN2018jgw | 01:47:18.9 | -32:21:35.8 | 20181129 | ATLAS | 20.24 | 0.097 | Ia | premax |
OGLE18jhf | SN2018jhf | 00:35:54.7 | -75:38:15.6 | 20181122 | OGLE | 19.17 | 0.058 | ? | premax | (1)
(1) The spectrum of SN2018jhf is consistent either with a SN Ia (91T-like) or SN Ic, both before maximum. It shows clear Halpha and [S II] lines. By comparing the SN and the host galaxy spectra, we conclude that these emission lines are from a HII region of the host. The light curve of SN2018jhf had a fast rise of 1.5 mag in 2 days. The last non-detection was 12 days before our spectral observations, suggesting that the luminosity will continue increasing for a few more days. Adopting a standard cosmology with H0 = 70 km/s/Mpc, we obtain a distance modulus of 37.1 mag. This gives a current absolute magnitude of about -19.1. Taking into account this previous analysis, the object could reach a peak absolute magnitude of around -20 mag, being too high for both SN 91T-like and Ic. This picture could be explained by a superchandra scenario. A new spectrum will be necessary to help to clarify the spectral type.
