Spectroscopic Classifications of Optical Transients with Mayall/KOSMOS

ATel #9335; C. D. Kilpatrick, M. R. Siebert, R. J. Foley (UCSC), Y.-C. Pan (Illinois), S. W. Jha (Rutgers), A. Rest (STScI), D. Scolnic (Chicago/KICP)
on 7 Aug 2016; 12:07 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Charles Kilpatrick (charlesk@email.arizona.edu)

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We report the following classifications of optical transients from spectroscopic observations with KOSMOS on the KPNO Mayall 4-m telescope. Targets were supplied by the GAIA, ATLAS, and POSS. All observations were made on 2016 Aug 7 UT. Classifications were performed with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024).

 
Name | RA (J2000) | Dec (J2000) | z | Type  | Phase | Notes
 
Gaia16axr | 18:39:57.70 | +33:15:59.80 | 0.057 | Ia | +20 d | 
ATLAS16bwb | 23:34:25.28 | -06:34:42.30 | 0.03 | II | | (1) 
AT2016eoa | 00:21:23.10 | +22:26:08.30 | 0.021 | Ia | -9 d | (2) 

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) The SN has a blue continuum, indicating that it is young, and low-velocity P-Cygni Balmer lines. The P-Cygni features have a peak-to-trough velocity difference of ~1300 km/s. Assuming a redshift of 0.033 (determined by the peak of H-beta emission), we measure an H-alpha velocity of -1200 km/s. (2) We measure a Si II 6355 velocity of -13,900 km/s. The Si II 6355 feature has a slight blue shoulder, which may be a relatively weak high-velocity component.