Spectroscopic Classifications of Optical Transients with Keck I + LRIS
ATel #13896; M. R. Siebert, G. Dimitriadis, R. J. Foley (UCSC)
on 25 Jul 2020; 15:35 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Georgios Dimitriadis (gdimitri@ucsc.edu)
Subjects: Optical, Supernovae
We report the classification of the optical transients from spectroscopic observations with the LRIS spectrograph on the Keck I telescope, made on 2020 Jul 25 UT. The targets were supplied by YSE and ASAS-SN. The classifications were performed with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024).
Name | IAU Name | RA (J2000) | Dec (J2000) | z | Type | Phase | Notes
PS20dho | AT2020kpz | 12:30:55.45 | +09:09:10.21 | 0.039 | II | | (1)
PS20eml | AT2020noz | 12:29:00.26 | +07:50:58.35 | 0.025 | IIn | | (2)
PS20gcz | AT2020pyy | 00:07:18.53 | +17:04:37.64 | 0.114 | Ia | -7d | (3)
ASASSN-20jb | AT2020qes | 00:13:26.26 | -28:01:56.68 | 0.026 | Ia | -7d | (4)
Notes:
When the redshift is given to 2 decimal places, it is derived from the SN spectrum. Otherwise, the redshift is determined from the host galaxy.
(1) We measure an H-alpha velocity of -4,700 km/s. (2) Long-rise (~40 days) and luminous (M ~ -18.5 mag) transient. The H Balmer series and He I have similar profiles, consisting of broad emission, narrow emission, broad absorption (-7,400 km/s), and possibly narrow absorption (-400 km/s) components, indicating strong interaction of the SN ejecta with a thick CSM shell, similar to SN 2006gy (Smith et al., 2010, ApJ, 709, 2). (3) We measure an Si II velocity of -12,400 km/s. (4) We measure an Si II velocity of -10,800 km/s.
