[vsnet-outburst 24997] ASASSN-20dy: new SU UMa-type dwarf nova

[Tonny Vanmunster tonny.vanmunster@gmail.com via vsnet-outburst]

Dear colleagues,

I have just finished analysing my unfiltered CCD observations of ASASSN-20dy (aka ZTF20aaurhdm), obtained this night (2020, Apr 16/17) at CBA Belgium Observatory, using a 0.40-m f/10.0 telescope and STT-3200ME CCD camera, under a very clear sky.

The resulting lightcurve clearly shows the presence of superhumps, with an amplitude of 0.17 mag, hence establishing ASASSN-20dy as a new SU UMa-type dwarf nova. A period analysis on the detrended lightcurve, using the ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.0, under development), yields a combined superhump period of 0.0550 +/- 0.0012d. The object was at mag 15.3 (CV) on Apr 16th.

Observations will be sent to AAVSO, CBA and VSNET for further analysis.

Follow-up observations are highly recommended to refine the superhump period and to study its further evolution.

Best regards
Tonny

-- 
Tonny Vanmunster
CBA Belgium Observatory
CBA Extremadura Observatory
www.cbabelgium.com
www.peranso.com