Liverpool Telescope classification of Gaia16ams and Gaia16aoy
ATel #9062; M. Fraser (IoA), L. Wyrzykowski (Warsaw), A. Hourihane, S. T. Hodgkin, S. Mattila, D. Harrison (IoA),Z. Kostrzewa-Rutkowska (Warsaw/SRON), N. Blagorodnova (Caltech)
on 18 May 2016; 18:56 UT
Credential Certification: Morgan Fraser (mf@ast.cam.ac.uk)
Subjects: Optical, Cataclysmic Variable, Star, Transient
We report spectroscopic classifications obtained using the robotic Liverpool Telescope + SPRAT (R~350; 400-800 nm) on the night of 2016 May 17.
Gaia16ams has a red spectrum, with broad molecular absorption features consistent with a late spectra-type star. The lightcurve of Gaia16ams was roughly constant at magnitude 16.2 for over a year, before fading by more than a magnitude on 2016 May 5, consistent with an eclipsing binary.
Gaia16aoy displays narrow (<1000 km/s) emission lines from H and HeI (5876, 7065 Ang) at their rest wavelengths. Gaia16aoy is a UV source previously seen by GALEX, that has shown an erratic lightcurve over the past year, with +/- 0.6 mag variation about its mean magnitude. In May 2016 it declined to G~17.1, compared to G~15.7 one year before. The spectra and lightcurve are consistent with a dwarf nova, and in particular the photometric variability is consistent with that seen in Z Cam objects, which show rapid variability and occasional pauses in their lightcurves.
We acknowledge ESA Gaia, DPAC and the Photometric Science Alerts Team (http://gsaweb.ast.cam.ac.uk/alerts).
