[vsnet-alert 22560] ASASSN-18wa: new SU UMa type dwarf nova

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

Dear colleagues,

I have just concluded the analysis of my 2018, Sep 23/24 unfiltered CCD photometry session of ASASSN-18wa. Observations were made at CBA Extremadura Observatory,  using a 0.40-m f/5.1 telescope and SX-46 CCD camera, under very clear skies but with strong moonlight. 

 

The resulting light curve clearly reveals the presence of superhumps with an amplitude of 0.15 mag, hence classifying this object as a new SU UMa type dwarf nova. A preliminary period analysis using the ANOVA, Lomb-Scargle and PDM methods (Peranso), yields a combined superhump period of 0.0550 +/- 0.0011d.  The object was at mag 13.35 (CV) on Sep 24th.  

 

The superhump structure shows secondary humps, which might indicate that we are actually observing early superhumps. Follow-up observations are encouraged, and I have another session of ASASSN-18wa scheduled from Sep 25, 01:00 UT till 04:37 UT. Skies are clear again at CBA Extremadura Observatory.

 

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

 

Best regards
Tonny


 

Tonny Vanmunster
CBA Belgium Observatory
CBA Extremadura Observatory
 <http://www.cbabelgium.com> www.cbabelgium.com

 <http://www.peranso.com> www.peranso.com