The program started in 2011 with the aim to classify all transients that are accessible from Asiago and are bright enough for our telescope/instrumentation. We use mainly the 1.82m Copernico telescope of Cima Ekar and, if not available, the 1.22m Galileo telescope of the Pennar station. A few cases of transients classified by our group with other facilities (eg. TNG) are included in the database.
Transient classification information and spectra (fits format) are made immediately available at our site. The spectra are semi-automatic reduction with archive calibration data. Please keep this in mind when using them.
For SN classification we compare the output of two automatic SN classification codes: Gelato (Harutyunyan et al. 2008, A&A 488, 383) and SNID (Blondin and Tonry 2007, Ap.J. 666, 1024).
If you use some of the information posted in these pages please make a reference to the paper Tomasella etal. 2014, A.N. 335, 841.
Discovered by: ASASSN
The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic observation of ASASSN-19ku (SN2019dwy) and SN 2019ehk. The first target was supplied by the All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014) in Atel#12713, while SN 2019ehk was reported in the Transient Name Server (https://wis-tns.weizmann.ac.il/object/2019ehk) and already classified in Atel #12707 by Dimitriadis et al.The observation was performed with the Asiago 1.82m Copernico Telescope (+AFOSC; range 340-820 nm; resolution 1.4 nm).
Survey name | IAU name | Host galaxy | Disc. Date (UT) | Obs. Date (UT) | redshift. | type | phase | notes ASASSN-19ku | 2019dwy | 2MASX J11141082+7046053| 2019-04-24 17:32:36| 2019-05-01 22:43:34| 0.045 | Ic | around max| 1 SN 2019ehk | 2019ehk | NGC 4321 | 2019-04-29 22:27:50| 2019-05-01 20:02:36| 0.005 | CC | early | 2
(1) The spectrum of this nuclear transient is similar to those of Type Ic supernovae soon after maximum. The redshift has been deduced with SNID/GELATO SN template fitting.
(2) The spectrum still show a red, mostly featureless continuum as described in Atel#12707. The NaID doublet is yet very strong (we measure an EW~0.48 nm) indicating significant dust absorption. A shallow, broad emission line is now clearly visible centred at about 587.6 nm, rest frame, which we identify as He I. Its FWHM implies an expansion velocity of about 15000 km/s. Red-wards of this feature an even shallower, very broad emission is detected, which we interpret as a blend of H-alpha, He I 667.8nm and He I 706.5 nm broad emissions. He I 492.2 nm is possibly also visible in the blue part of the spectrum. We confirm this event as a young core collapse SN in agreement with Atel #12707.
The classification was performed using the GELATO (Harutyunyan et
al. 2008, A&A, 488, 383)
and SNID (Blondin and Tonry 2007, ApJ, 666, 1024) tools.