OT UMa and GU leo: Two middle-contact w UMa binaries with similar stellar components

Kjurkchieva, Diana; Michel, Raul; Guerrero, Carlos
New Astronomy, Volume 72, p. 9-14 (2019).


We present photometric observations of the W UMa binaries OT UMa and UG Leo. Our results from the light curve solutions are: (i) The two targets show partial eclipses; (ii) The components OT UMa and UG Leo are of G spectral type; (iii) Detailed q-search analysis was carried out for determination of the mass ratios; (iv) The two binaries are of W subtype with middle fillout factors. We estimated masses, radii and luminosities of the target components by our light curve solutions and using GAIAdistances. It turned out that their values are similar for the two targets. The paper presents a discussion on the determination of the temperatures and mass ratios of partially-eclipsing W UMa stars.