Spectroscopic Classification of SN 2018dx (=ASASSN-18aj) as a Type Ia Supernova
ATel #11161; Han Lin, Danfeng Xiang, Liming Rui, Xiaofeng Wang (Tsinghua University), Feng Xiao, Juanjuan Ren, Tianmeng Zhang (NAOC), and Jujia Zhang (YNAO)
on 13 Jan 2018; 02:10 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Xiaofeng Wang (wang_xf@mail.tsinghua.edu.cn)
Subjects: Optical, Supernovae, Transient
We obtained an optical spectrum (range 375-830 nm) of SN 2018dx(=ASASSN-18aj), discovered by All Sky Automated Survey for Supernova(ASAS-SN), on UT 11.8 2018 with the 2.16-m telescope (+BFOSC) at Xinglong Station of National Astronomical Observatories of China (NAOC). The spectrum is consistent with that of a type Ia supernova a few days before the maximum light. 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 2003du at t = -5.0 day from the maximum light. After correcting for
a redshift of 0.06(+/-0.005) for its host galaxy SDSS J091612.25+390341.8, an expansion velocity from 10700 km/s to 13800 km/s can be derived from the absorption minimum of Si II 635.5 nm line. Our classification spectrum is also posted on the IAU Transient Name Sever: https://wis-tns.weizmann.ac.il/object/2018dx