AstroNote 2020-234

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2020-11-21 16:38:39
Type: Object/s-Discovery/Classification
ePESSTO+ spectroscopic classification of optical transients
Authors: M. Gromadzki, N. Ihanec (Warsaw), E. Callis, M. Fraser (UCD), R. Carini (INAF), G. Pignata (UNAB), P. Wiseman (Southampton), I. Arcavi (Tel Aviv University), J. Anderson (ESO), T. Muller Bravo (Southampton), T.-W. Chen (Stockholm), C. Inserra (Cardiff), E. Kankare (Turku), M. Nicholl (Birmingham), O. Yaron (Weizmann), D. Young (QUB), I. Manulis (Weizmann), S. J. Smartt, K. W. Smith, S. Srivastav (QUB), K. C. Chambers, T. de Boer, J. Bulger, J. Fairlamb, M. Huber, C.-C. Lin, T. Lowe, E. Magnier, A. Schultz, R. J. Wainscoat, M. Willman (IfA, Univ. Hawaii), J. Tonry, L. Denneau, A. Heinze, H. Weiland, H. Flewelling (IfA, Univ. of Hawaii), B. Stalder (LSST), A. Rest (STScI), O. McBrien (QUB)
Source Group: ePESSTO+
This report includes classifications of 6 Type Ia's, 1 Type II, and 1 ambiguous object. SN2020zoq is a young Type II, with a blue continuum and clear P-Cygni Balmer series and NaD/HeI. AT2020znl has a narrow emission feature (at the edge of the telluric B-band) which we tentatively associate with Halpha. The continuum is blue and largely featureless aside from two apparent absorptions at "rest frame" 4757, 4833 Ang, and was initially classified as a possible TDE in ATel #14190. We encourage followup observations.

ePESSTO+, the advanced Public ESO Spectroscopic Survey for Transient Objects (Smartt et al. 2015 2015A&A...579A..40S), reports the following supernova classifications.

Targets were supplied by the Pan-STARRS Survey for Transients (Chambers et al. 2016 2016arXiv161205560C), the ATLAS survey (Smith et al. 2020 2020arXiv200309052S), the Zwicky Transient Facility ZTF (Bellm et al. 2019 2019PASP..131a8002B) - data stream processed through the Lasair broker (Smith, Williams, Young et al. 2019 2019RNAAS...3a..26S), and the All Sky Automated Survey for SuperNovae ASAS-SN (see Shappee et al. 2014 2014ApJ...788...48S).

Observations were performed on the ESO New Technology Telescope (NTT) at La Silla on the night of 2020 Nov 20, using EFOSC2 and Grism 13 (3985-9315A, 18A resolution). Classifications were done using SNID (Blondin & Tonry 2007 2007ApJ...666.1024B).

The classification spectra and additional details can be obtained from (via WISeREP) and the IAU Transient Name Server.

The classified objects are listed in the Related Objects table below.

Show current TNS values
CatalogNameReported RAReported DECReported Obj-TypeReported RedshiftHost NameHost RedshiftSourcePhase (days)RemarksTNS RATNS DECTNS Obj-TypeTNS Redshift
TNS2020zpj [ZTF20acqjmzk]22:43:38.633-14:04:04.47SN Ia0.1WISEA J224338.65-140405.1at maxRedshift from SNID match.22:43:38.633-14:04:04.47SN Ia0.1
TNS2020zid [ZTF20acppruo]23:22:06.059-06:12:47.21SN Ia0.13SDSS J232206.10-061247.50.118at maxRedshift from SNID match.23:22:06.059-06:12:47.21SN Ia0.13
TNS2020aabz [ZTF20acqzjqz]02:54:59.029+04:03:36.86SN Ia0.03-7 to -4Redshift from SNID match.02:54:59.040+04:03:37.01SN Ia0.0241
TNS2020aakp [ASASSN-20ol]06:43:06.166-74:12:48.89SN Ia0.028PGC194800.023-7 to -4Redshift from SNID match.06:43:06.150-74:12:49.46SN Ia0.028
TNS2020zqo [ASASSN-20od]04:02:55.154-31:20:16.62SN Ia0.06WISEA J040255.26-312018.90.059658at maxRedshift from SNID match.04:02:55.180-31:20:16.62SN Ia0.06
TNS2020aagw [ATLAS20bfpg]08:38:58.367+05:47:27.60SN Ia0.05at maxRedshift from SNID match.08:38:58.365+05:47:27.64SN Ia0.048
TNS2020zoq [ASASSN-20oc]10:36:21.542+13:43:08.94SN II0.01UGC 057600.01004+1 to +2 weeksRedshift measured from emission lines. Blue continuum, clear P-Cygni Balmer series and NaD/HeI. Abs mag = -15.4, consistent with a nornal Type IIP.10:36:21.590+13:43:07.10SN II0.01
TNS2020znl [ZTF20acpvbbh]06:13:17.896-15:53:31.41Other0.043around maxRedshift measured from emission lines. Narrow emission feature (unfortunately at the edge of the telluric B-band) which we tentatively associated with Halpha. The continuum is blue and largely featureless aside from two apparent absorptions at *rest frame* 4757, 4833 Ang. Fitting a Gaussian to these absorptions gives an FWHM of 2,000 - 4,000 km/s. The lightcurve has a clear and smooth rise for ~10 days, and at z=0.043 has an absolute magnitude -19.3. Was initially classified as a possible TDE in ATel #14190.06:13:17.899-15:53:31.45SN II0.043