Spectroscopic classification of PTSS-17xsq (SN 2017hng) as a young 91T-like type Ia supernova
ATel #10895; J.-J. Zhang, J.-G. Wang (YNAO); X. F., Wang, W.-X., Li (THU); H.-J. Tan (CCU), B. Li, Z.-J. Xu, H.-B. Zhao, L.-F. Wang (PMO); D.-F. Xiang, L.-M. Rui, Z.-S. Yang (THU)
on 26 Oct 2017; 07:22 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Ju-Jia Zhang (jujia@ynao.ac.cn)
Subjects: Supernovae, Transient
Referred to by ATel #: 10896
We obtained an optical spectrum (range 380-880 nm) of PTSS-17xsq (SN 2017hng), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/ ), on UT 2017 Oct. 25.7 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories. The spectrum characterized by a blue continuum and prominent Fe III and Fe II lines is well matched to the 91T-like events at the early phase. Cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J., 666, 1024) shows that it matches with SN 1995bd at t = -9 days. After correcting for a redshift of 0.039 for its host galaxy 2MASX J04214029-0332267 (derived from the narrow H alpha emission in the spectrum of SN), an expansion velocity of about 14000 km/s can be deduced from the Fe III 5129, 5158 absorption minimum.
