Dear colleagues,

TCP J00534786+1617214 (aka ASASSN-25ei) was discovered by Y. Nakamura, Japan on 2025 Nov 1.5 at mag 14.4 U. The quiescent counterpart is a 22.0 g mag star, implying an outburst amplitude of ~7.6 mag.

I have just completed the analysis of my unfiltered CCD observations of TCP J00534786+1617214, obtained on 2025 Nov 08/09 at CBA Belgium Observatory. The data were acquired under clear skies with a 0.40-m f/10.0 telescope and a QHY-268M CMOS camera under clear skies.

The light curve clearly exhibits regular superhump modulations with an amplitude of 0.19 mag. Period analysis with ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.1) yields a combined superhump period of 0.0624 +/- 0.0010d. The object was measured at mag CV = 15.5 on Nov 08th.

Image calibration and photometry were performed with the latest release of Phoranso.

These results establish TCP J00534786+1617214 as a new SU UMa-type dwarf nova. Follow-up observations are encouraged.

I will submit my observations to AAVSO, CBA and VSNET for further analysis.

With kind regards,

Tonny

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Tonny Vanmunster

CBA Belgium Observatory

CBA Extremadura Observatory

http://www.cbabelgium.co http://www.cbabelgium.com/ m

PERANSO : The Light Curve and Period Analysis Software

http://www.peranso.co http://www.peranso.com/ m

PHORANSO: Photometric Reduction and Analysis Software

http://www.phoranso.com http://www.phoranso.com/