Spectroscopic Classifications of Optical Transients with SOAR

ATel #7937; Y.-C. Pan, R. A. Hounsell, S. Downing, R. J. Foley (Illinois), S. W. Jha (Rutgers), A. Rest (STScI), 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 21 Aug 2015; 22:13 UT
Credential Certification: Yen-Chen Pan (ycpan@illinois.edu)

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We report the following classifications of optical transients from spectroscopic observations with the Goodman spectrograph on the Southern Astrophysical Research (SOAR) telescope. Targets were supplied by the Pan-STARRS Survey for Transients (PSST) and All-Sky Automated Survey for Supernovae (ASAS-SN). All observations were made on 2015 Aug 20 UT. Classifications were performed with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024).

 
Name    | RA (J2000)  | Dec (J2000) |  z   | Type | Phase |  Notes
 
PS15bsg | 02:57:02.64 | +03:52:10.5 | 0.190 | Ia? | ~1 week | (1) 
PS15bsn | 03:33:15.07 | +00:34:27.6 | 0.071 | II |     | 
PS15bsp | 23:24:03.18 | -09:56:32.8 | 0.05 | Ia | ~1 week | (2) 
PS15bsq | 23:41:52.17 | -08:38:16.4 | 0.034 | Ia | -5d | (3) 
PS15bst | 23:34:01.02 | -13:17:45.3 | 0.09 | Ia | -5d | (4) 
PS15bsh | 03:06:48.13 | +04:31:41.7 | 0.048 | Ia | +29d | 
ASASSN-15oi | 20:39:09.09 | -30:45:20.71 | 0.02 | TDE? |     | (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) There is a line at ~4435 A. Although not definitive, if we associate this with [O II] 3727, we find a redshift of 0.19. If the redshift is correct, the spectrum is consistent with a SN Ia at +1 week. (2) We measure a Si II 6355 velocity of -7500 km/s. (3) We measure a Si II 6355 velocity of -12,200 km/s. (4) We measure a Si II 6355 velocity of -12,300 km/s. (5) We confirm the spectral feature (possibly He II 4686 at z ~ 0.02) observed by PESSTO (see ATEL #7936). The spectrum is similar to that of other TDE candidates.