Spectroscopic Classifications of Optical Transients with SOAR

ATel #8663; R. A. Hounsell, J. A. Miller, Y.-C. Pan, R. J. Foley (Illinois), A. Rest (STScI), S. W. Jha (Rutgers), D. Scolnic (Chicago/KICP), K. W. Smith, D. Wright, S. J. Smartt (QUB), M. Huber, K. C. Chambers, H. Flewelling, M. Willman, N. Primak, A. Schultz, B. Gibson, E. Magnier, C. Waters, J. Tonry, R. J. Wainscoat (IfA, Hawaii)
on 10 Feb 2016; 01:57 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Ryan Foley (rfoley@illinois.edu)

Tweet

We report the following classifications of optical transients from spectroscopic observations with the Goodman spectrograph (wavelength range 3300 - 7100 A) on the SOAR telescope. Targets were supplied by the Pan-STARRS Survey for Transients (PSST), the Catalina Real-Time Transient Survey (CRTS), and the Backyard Observatory Supernova Search (BOSS). All observations were made on 2016 Feb 9 UT. Classifications were performed with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024).

 
Name       | RA (J2000)  | Dec (J2000) |  z    | Type | Phase    |  Notes
 
PS16aep    | 08:16:24.59 | +25:59:35.2 | 0.045 | II   | +3 weeks | (1) 
PS16aer    | 10:54:58.19 | +14:16:17.7 | 0.056 | Ia   | -1 day   | (2) 
AT 2016aaj | 13:49:40.51 | +04:14:27.1 | 0.023 | II   | ~peak    | (3) 
SN 2016adj | 13:25:24.11 | -43:00:57.5 | 0.002 | IIb? |          | (4) 
 

Notes:

(1) PS16aep is also known as AT2016acq.

(2) PS16aer is also known as AT2016acs. We measure an Si II 6355 velocity of -12,400 km/s.

(3) AT 2016aaj is also known as SNhunt303. We measure an H-alpha velocity of -10,200 km/s.

(4) SN 2016adj was tentatively classified as a SN II (ATEL #8655), with a revised classification as a SN Ib (ATEL #8657). Our spectrum is similar to some SNe Ib, including SN 1999dn as mentioned in ATEL #8657. It is also similar to some SNe II and IIb. There are strong features that likely correspond to He I 5876 and He I 6678 with a common expansion velocity of -7000 km/s. There is a strong feature at ~4560 A, which may be He II 4686 at a similar velocity. There is also another strong feature at 6415 A that could correspond to H alpha at a similar velocity. While this last feature may be something other than H alpha, we do not exclude the possibility that SN 2016adj is a SN IIb.

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.