Spectroscopic Classification of ASASSN-17ol, ASASSN-17op and ASASSN-17or with du Pont
ATel #10963; M. R. Drout (Carnegie Obs.), J. L. Prieto (UDP/MAS), S. Dong (KIAA/PKU), B. J. Shapee (IfA Hawaii)
on 13 Nov 2017; 14:44 UT
Credential Certification: Jose L. Prieto (jose.prietok@mail.udp.cl)
Subjects: Optical, Supernovae, Transient
We obtained low-resolution optical spectra (range 3600-9600 Angs., FWHM res ~ 8 Angs.) of ASASSN-17ol/AT2017hxy (ATel #10960), ASASSN-17op/AT2017hyt, and ASASSN-17or/AT2017hyx on UT 2017 Nov. 13.2 with WFCCD mounted on the du Pont 2.5m at Las Campanas Observatory. All three objects show features characteristic of Type Ia supernovae caught at or before peak brightness. We performed cross-correlation of the spectra with a library of supernova spectra using SNID (Blondin & Tonry 2007, ApJ, 666, 1024). ASASSN-17ol and ASASSN-17op are consistent with SN 1991T-like spectral templates a few days before maximum light. ASASSN-17or is normal Type Ia around peak, with strong host-galaxy contamination. We detect nebular emission lines (H-beta, H-alpha, and [N II]) from the host galaxy in the spectrum of ASASSN-17ol and measure z=0.0615 from the H-alpha line, which is consistent with the redshift measured from the SN features by SNID (z=0.062).
