Spectroscopic Classifications of Optical Transients with Keck I/LRIS
ATel #10983; D. O. Jones, M. R. Siebert, R. J. Foley (UCSC)
on 18 Nov 2017; 02:07 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Ryan Foley (foley@ucsc.edu)
Subjects: Optical, Supernovae
We report the following classifications of optical transients from spectroscopic observations with LRIS on the Keck I 10-m telescope. Targets were supplied by TNTS and ATLAS. All observations were made on 2017 Nov 17 UT. Classifications were performed with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024).
Name | IAU Name | RA (J2000) | Dec (J2000) | z | Type | Phase | Notes
| AT2017ifh | 06:35:03.56 | +50:26:27.90 | 0.039 | Ic-BL | pre-max | (a)
ATLAS17nel | AT2017ift | 20:53:30.68 | -10:03:10.83 | 0.038 | Ia | -1 d | (b)
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.
(a) Spectrum is similar to broad-lined SNe Ic such as SNe 1998bw and 2002ap before maximum, however with some differences in velocity. There is a feature at ~6000 A (in the rest frame), which if Si II 6355, would have a velocity of -16,400 km/s. There is a very broad feature covering ~6500 - 8400 A. If it is primarily the Ca II NIR triplet, it would have a velocity of -33,900 km/s, but we assume this feature is a blend of Ca II and O I 7774.
(b) We measure a velocity of -11,700 km/s for Si II 6355.