SOAR telescope spectroscopic classification of optical transients
ATel #12080; R. Cartier (CTIO), G. Terreran (Northwestern), R. Margutti (Northwestern), P. Blanchard (CfA/Harvard), J. Espinoza (CTIO) and P. Ugarte (CTIO)
on 5 Oct 2018; 12:37 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Regis Cartier (rgcartier@gmail.com)
Subjects: Optical, Supernovae
We report the following supernova classifications. The targets were supplied by 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 ). The observations were performed on the night of 2018 October 03 at the 4.1-m SOAR Telescope equipped with the Goodman High Throughput Spectrograph using the 400 lines/mm grating, and a slit width of 1.0 arc second, resulting in a spectral coverage from 380 nm to 775 nm with a resolution of 0.636 nm. Classifications were done with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024).
Survey Name | IAU Name | RA (J2000) | Dec (J2000) | Disc. Date | Source | Disc Mag | z | Type | Phase | Notes
ASASSN-18wr | SN2018hbh | 22:20:35.87 | -30:11:54.7 | 2018-10-03 | ASAS-SN | 17.7 | 0.072 | Ia | at max | (1,2)
ASASSN-18wg | SN2018gys | 23:17:53.47 | -42:12:46.7 | 2018-09-30 | ASAS-SN | 17.95 | 0.060 | Ia | at max |
ASASSN-18vx | AT2018gqc | 00:21:13.52 | -57:45:10.8 | 2018-09-18 | ASAS-SN | 17.7 | 0.134 | AGN | | (1)
ASASSN-18ve | SN2018gex | 21:31:28.62 | -50:44:59.9 | 2018-09-10 | ASAS-SN | 18.1 | 0.030 | II | past max | (3)
ASASSN-18oa | SN2018cvn | 01:30:27.12 | -26:47:06.8 | 2018-06-26 | ASAN=SN | 16.7 | 0.019 | II | past max | (4)
(1) Redshift obtained from host galaxy emission lines.
(2) Similar to SN1991T.
(3) The SN2018gex was discovered by ASAS-SN (ATel #12063), a classification spectrum was obtained by ePESSTO on 2018-09-15
(ATel #12040). The ePESSTO spectrum is characterized by a blue continuum with H-alpha emission at z=0.03 (ATel #12040),
however it was not possible to obtain a definitive classification. SN2018gex evolved since then, and the spectrum
obtained with Goodman corresponds to a SN type II, similar to SN2004et after maximum.
(4) SN2018cvn was discovered by ASAS-SN shortly after the SN explosion (ATel #11832), then a few days later it was
classified as a SN IIn a with Goodman at the SOAR telescope (ATel #11816). The classification spectrum was similar to the
early spectrum of SN1998S, showing very blue continuum, weak broad Balmer lines and strong blended C III and N III lines
(ATel #11816), probably, originated from circumstellar material ejected by the star shortly before the explosion.
SN2018cvn evolved dramatically and several days later shows a spectrum similar to SN2004dj, a SN II without signs of
ongoing ejecta-CSM interaction.
