Gaia18awg is a new SU Uma type dwarf nova during a superoutburst

ATel #13468; A. Simon (National Taras Shevchenko University of Kyiv, Ukraine), I. Izviekova (ICAMER Observatory of NASU, Ukraine), W. Ogloza (Pedagogical University of Cracow, Poland), M. Zejmo (Kepler Institute of Astronomy, University of Zielona Gora, Poland), E. Pavlenko (Crimean Astrophysical Observatory, Republic of Crimea), V. Vasylenko (National Taras Shevchenko University of Kyiv, Ukraine) E. Sonbas (Department of Physics, Adiyaman University, Turkey)
on 12 Feb 2020; 11:22 UT
Credential Certification: Andrew Simon (skazhenijandrew@gmail.com)

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We report the results of recent photometric observations of AT2018asi/Gaia18awg performed on 2020, February 07-09 with the AZT-8 0.7-m f/4 reflector at the Lisnyky Observatory near Kyiv, Zeiss-600 f/4 reflector at the Mt. Suhora Astronomical Observatory and ADYU60 f/6.5 reflector at the Observatory of Adiyaman University.

The erratically variable Gaia source Gaia19btn/AT2018asi was discovered on 2018-04-04 by A. Delgado, D. Harrison, S. Hodgkin, M. van Leeuwen, G. Rixon, A. Yoldas (University of Cambridge), on behalf of Gaia Alerts team at magnitude G = 14.89. From observations taken at the Lisnyky Observatory on 2020-02-07 (JD 2458887.31 - 2458887.36) using the Gaia Calibration Server for the photometric calibration of datasets we obtained following magnitude of the source (not corrected for the Galactic foreground extinction): R = 14.93 ± 0.02, which means that the object was in outburst. No periodicity were detected at this date. Next observations were carried out on 2020-02-08 (JD 2458888.24 - 2458888.43) at the Mt. Suhora Astronomical Observatory and on 2020-02-09 (JD 2458889.22 - 245889.37) at the Lisnyky Observatory and at the Observatory of Adiyaman University. During these observations we detected strong periodicity with amplitude 0.2 mag using ISDA package (Pelt, Jaan. Irregularly Spaced Data Analysis User Manual, Printed by Helsinki University, 267 pp. (1992)). After removing trend corresponding to outburst profile we constructed periodogram and determined the period to be 0.0829(3) d. Taking into account that the object is blue in the outburst, outburst amplitude is above 4 mag and period during outburst is 0.0829(3) d we can suggest that this object appears to be a SU UMa type dwarf nova during a superoutburst and demonstrates superhumps with period 0.0829(3) d and amplitude 0.2 mag. Further observations are encouraged.

We acknowledge ESA Gaia, DPAC and the Photometric Science Alerts Team (http://gsaweb.ast.cam.ac.uk/alerts), as well as Cambridge Photometry Calibration Server (CPCS) (http://gsaweb.ast.cam.ac.uk/followup/).