Dear colleagues,
I have just finished analysing my unfiltered CCD observations of ASASSN-22lk, obtained on 2022, Sep 27/28 & Sep 28/29 at CBA Extremadura Observatory (Spain), using a 0.40-m f/5.1 telescope and SX-46 CCD camera under clear skies. I have been observing this object during multiple nights between Sep 21st and now. The past 2 nights showed the appearance of superhumps with an amplitude of 0.31 mag. A period analysis using the ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.0), yields a combined superhump period of 0.0560 +/- 0.0004d. The object was at mag CV = 14.0 on Sep 29th.
The superhump profile shows no signs of a double-waved pattern, but early superhumps are most likely present in my data (to be confirmed). The large outburst amplitude of ~9 mag, and the long time for superhumps to develop (approx. 9 days) make this a most likely WZ Sge-type dwarf nova. Follow-up observations are recommended to further track the evolution of the superhumps.
I will send my observations to AAVSO, CBA and VSNET for further analysis.
Best regards Tonny
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Tonny Vanmunster CBA Belgium Observatory CBA Extremadura Observatory http://www.cbabelgium.com
PERANSO : The Light Curve and Period Analysis Software http://www.peranso.com