Spectroscopic observations of four transients by NUTS (NOT Un-biased Transient Survey)

ATel #9990; H. Kuncarayakti, S. Mattila, J. Harmanen, T. Kangas, T. Reynolds, A. Somero (Turku), L. Wyrzykowski, A. Hamanowicz, Z. Kostrzewa-Rutkowska (Warsaw Observatory), M. Fraser (University College Dublin), M. Stritzinger (Aarhus), A. Pastorello, N. Elias-Rosa (Padova), P. Lundqvist, F. Taddia, M. Ergon (OKC)
on 23 Jan 2017; 19:53 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Hanindyo Kuncarayakti (kuncarayakti@gmail.com)

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The Nordic Optical Telescope (NOT) Un-biased Transient Survey (NUTS; ATel #8992) reports spectroscopic classifications of two supernovae in anonymous host galaxies, one cataclysmic variable star, and one object of undetermined class. The candidates were discovered by the Gaia Photometric Science Alerts and the ATLAS survey.

The observations were performed with the 2.56 m Nordic Optical Telescope equipped with ALFOSC (range 350-950 nm; resolution 1.6 nm FWHM).

 
Survey Name    | IAU Name   | Discovery (UT)  | Discovery mag | Observation (UT) | Redshift | Type | Phase                      | Notes  
Gaia17acy      | AT 2017jt  | 2017-01-14.89   | 18.78         | 2017-01-22.89    | 0.175    | ?	   |                            | (1) 
Gaia17aea      | SN 2017lc  | 2017-01-11.88   | 18.33         | 2017-01-23.11    | 0.05     | Ia   | around 1 week before max	| (2) 
Gaia17aej      | AT 2017lu  | 2017-01-17.60   | 19.12         | 2017-01-23.04    | 0.000    | CV   |	                        | (3) 
ATLAS17air     | SN 2017jl  | 2017-01-16.22   | 17.71         | 2017-01-22.87    | 0.02     | Ia   | around 1 week before max	| (4) 

(1) Blue continuum. Object coincides with a faint galaxy. Redshift was derived from host emission lines. At this redshift, the Gaia G-band discovery magnitude corresponds to absolute magnitude around -20.8 mag. Note that this absolute magnitude estimate does not take into account host galaxy contamination.
(2) Spectrum resembles normal SNe Ia. Redshift was derived from SN features.
(3) Blue continuum, intermediate-width Balmer emission lines at z = 0.
(4) Spectrum resembles normal SNe Ia. Redshift was derived from SN features.

Classifications were performed using the GELATO (Harutyunyan et al. 2008, A&A, 488, 383) and SNID (Blondin and Tonry 2007, ApJ, 666, 1024) tools. Calibrated spectra and additional information can be retrieved in the IAU Transient Name Server. We acknowledge ESA Gaia (http://cosmos.esa.int/gaia), and the DPAC Photometric Science Alerts Team (http://gaia.ac.uk/selected-gaia-science-alerts) (Rixon et al, 2014, ATel #6593).