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Spectral classification of optical transients with du Pont telescope

ATel #10240; Nidia Morrell (Las Campanas Observatory), Ben Shappee, Maria Drout (Hubble Fellow, Carnegie Observatories), Subo Dong (KIAA-PKU)
on 3 Apr 2017; 16:59 UT
Credential Certification: Nidia Morrell (nmorrell@lco.cl)

Subjects: Optical, Supernovae, Transient

We obtained optical spectroscopy (range 370-920 nm) of 11 transients with the 2.5-m du Pont telescope (+WFCCD) at Las Campanas Observatory between March 26 and 29 UT. The data were cross-correlated with a library of supernova spectra via the Supernova Identification tool (Blondin and Tonry, 2007, ApJ, 666, 1024). Results are presented in the following table:

 
Name          |    AT   |Disc. ATel   | Spec. Type | Phase | Obs. date| Redshift   | notes| 
------------------------------------------------------------------------------- 
              | 2017bzb | ATel #10165 | II         | 10-15 |   28.4   |0.003132/NED|  1 
              | 2017bzc | ATel #10165 | Ia         |  14   |   29.4   |0.005365/NED|  2 
              | 2017caw | ATel #10165 | II         |   0   |   29.2   |0.027145/NED|  3 
ASASSN-17dm   | 2017cbg | ATel #10176 | M-type star|       |   26.2   |  ---       |  4 
ASASSN-17ds   | 2017cfq | ATel #10199 | II?        |       |27.1,28.1 |0.021648/NED|  5 
ASASSN-17dt   | 2017cig | ATel #10199 | Ia         | +10   |   26.2   |0.046/SNID  |  6 
ASASSN-17du   | 2017cii | ATel #10200 | Ia         |+1 - +4|   27.4   |0.033253/NED|  7 
ASASSN-17ea   | 2017cjr | ATel #10206 | Ia         |  -5   |   26.2   |0.014440/NED|  8 
ATLAS17dcl    | 2017cjt |             | Ia         |  -5   |   27.0   |0.009376/NED|  9 
DLT17ah       | 2017ckg | ATel #10214 | II?        |       |27.3,29.2 |0.017495/NED|  10 
ASASSN-17ed   | 2017cnn | ATel #10226 | Ia         |  +9   |   26.0   |0.040308/NED|  11 
 
Notes: 
1.-Adopting the NED redshift, the minimum of the H-alpha absorption is blueshifted by 7700 km/s.  Best SNID match to SN 1999em at 11 days past maximum. 
2.-Best SNID match to SN 1995D at 15 days after maximum light. Adopting the redshift from NED, we derive from the minimum of the Si II 635.5 absorption an expansion velocity of 10200 km/s. 
3.-Adopting redshift from NED, the minimum of H-alpha absorption is blueshifted by 8000 km/s.  Best SNID match to SN 2004dj at maximum light. 
4.-Also typed in ATel #10212. 
5.-Blue featureless continuum possibly indicative of type II SN soon after explosion.  See also ATel #10225. Strong narrow emission lines in the spectrum, likely from a nearby H II region, place the SN at a redshift 0.022+/-0.001. 
6.-Also typed in ATel #10209. Best SNID match to SN 2002ha at +10 days.  Minimum of Si II 635.5-nm absorption yields 10500 km/s expansion velocity. 
7.-Also typed in ATel #10212. Minimum of the Si II 635.5-nm absorption blueshifted by 10000 km/s, assuming the host redshift from NED. SNID yields many excellent matches to normal type Ia SN between 1 and 4 days from maximum brightness. 
8.-Also typed in ATel #10212. Minimum of Si II 635.5-nm blueshifted by 11460 km/s.  Best SNID match is SN 2005bc at -5 days. 
9.-Also typed in ATel #10225. SNID best match to SN 2005cf at -5 days.  Minimum of Si II 635.5-nm absorption yields expansion velocity of 12600 km/s, assuming the NED redshift for the host. 
10.-Also typed in ATel #10218. Blue continuum with broad emission lines compatible with very young core collapse supernova. 
11.-SNID provides many excellent matches with normal type Ia supernovae at 9-10 days past maximum. Minimum of Si II 635.5-nm absorption blueshifted at 10600 km/s.