Spectroscopic Classifications of Optical Transients with Keck I + LRIS
ATel #14766; M. R. Siebert, K. Davis, S. Tinyanont, R. J. Foley (UCSC), E. Strasburger(UCB)
on 8 Jul 2021; 19:48 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Samaporn Tinyanont (stinyanont@ucsc.edu)
Subjects: Optical, Supernovae
We report the following classifications from spectroscopic observations with the LRIS spectrograph on the Keck I telescope, made on 2021 Jul 8 UT. The targets were supplied by ATLAS, ZTF, and YSE. The classifications were performed with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024).
Name | IAU Name | RA (J2000) | Dec (J2000) | z | Type | Phase | Notes
ATLAS21baof | AT2021skf | 12:53:57.37 | -08:46:14.97 | 0.01175 | Ia | -12d | (1)
ZTF21abjxoae | AT2021sld | 15:00:37.750 | -08:17:00.58 | 0.104 | Ia | -4d | (2)
PS21grp | AT2021qxv | 15:18:59.295 | -03:11:45.08 | 0.183 | TDE? | | (3)
ATLAS21baoh | AT2021skn | 16:24:49.004 | +39:44:04.73 | 0.02974 | II | peak | (4)
ZTF21abjyiiw | AT2021sjt | 20:37:19.200 | +66:06:23.08 | 0.00475 | II | young | (5)
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 a Si II velocity of -17,600 km/s.
(2) We measure a Si II velocity of -11,100 km/s.
(3) There is a weak emission feature consistent with He II 4686 with a FWHM of 12,000 km/s. At z = 0.183, the peak luminosity is M ~ -19 mag. These observations are consistent with a TDE classification, but further observations are necessary to confirm.
(4) We measure an H-alpha absorption velocity of -11,600 km/s.
(5) We measure an H-alpha absorption velocity of -10,000 km/s. The continuum appears strongly reddened with E(B-V) ~ 0.8 mag. We detect the Na D absorption from both the host and the Milky Way.
