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arXiv · 2608.25516

BV photometry of the cataclysmic variable LY UMa

L. Dankova·D. Marchev·S. Peneva·R. Zamanov
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Abstract

We performed B- and V-band photometry of the probable dwarf nova LY UMa. We find that it has apparent magnitude V=15.26+/-0.03 on 2024-04-14, V=15.43+/-0.02 on 2025-04-28, and V = 15.57+/-0.02 on 2025-06-02. Using the GAIA distance d=310pc, we find that the lower values correspond to absolute V band magnitude M_V=7.94-8.10 and indicate that the mass donor of LY UMa is a K7-K8V star with M_V=8.0-8.5. Our B-band measurements show slightly bluer B-V index of LY UMa than that of its donor, consistent with its nature as a cataclysmic variable. Close to LY UMa is the Active Galaxy Nucleus Mrk 153, for which we estimate V=14.81+/-0.03.

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L. Dankova, D. Marchev, S. Peneva, R. Zamanov. 2026-08-26. BV photometry of the cataclysmic variable LY UMa. https://arxiv.org/abs/2608.25516

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