LJT Spectroscopic Classification of ATLAS19bdts (AT2019xud) as a young SN Ia
ATel #13373; Jujia Zhang (YNAO), Xiaofeng Wang (THU)
on 26 Dec 2019; 02:36 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Ju-Jia Zhang (jujia@ynao.ac.cn)
Subjects: Optical, Supernovae
We obtained an optical spectrum (range 350-880 nm) of ATLAS19bdts (AT2019xud), discovered by ATLAS, on UT 2019 Dec. 25.6 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at the Li-Jiang Observatory of Yunnan Observatories. The spectrum is matched to the young type Ia supernova at about two weeks before the maximum. 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 2006cp at t = -10 days. The clear Na ID absorption (EW~1.48A) from the host galaxy indicates significant extinction, which makes the spectrum looks redder. Given a redshift of 0.0274 for the host galaxy (via the Ha emissions), an expansion velocity of about 16500 km/s can be deduced
from the absorption minimum of Si II 6355. The high-velocity features of Ca II IRT and Ca II HK reach a velocity of about 30000km/s.
