RAT J1953+1859: a dwarf nova discovered through high amplitude QPOs in quiescence

Ramsay, Gavin
Hakala, Pasi
Barclay, Thomas
Wheatley, Peter
Marshall, George
Lehto, Harry
Napiwotzki, Ralf
Nelemans, Gijs
Potter, Stephen
Todd, Ian
Journal Title
Journal ISSN
Volume Title
We report the discovery of an accreting binary, RAT J1953+1859, made during the RApid Temporal Survey (RATS) on the Isaac Newton Telescope. It showed high amplitude (0.3 mag) quasi-periodic oscillations on a timescale of ~20 mins. Further observations made using the Nordic Optical Telescope showed it to be ~4 mag brighter than in the discovery images. These photometric observations, together with radial velocity data taken using the William Herschel Telescope, point to an orbital period of ~90 mins. These data suggest that RAT J1953+1859 is a dwarf novae of the SU UMa type. What makes RAT J1953+1859 unusual is that it is the first such system to be discovered as a result of high amplitude QPOs during quiescence. This suggests that high-cadence wide-field surveys could be another means to discover cataclysmic variables as a result of their short period variability.
Comment: Accepted for publication in MNRAS
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies