Resumo

KJURKCHIEVA, Diana P.; POPOV, Velimir A.; VASILEVA, Doroteya L.  e  PETROV, Nikola I.. Observations and light curve solutions of the eclipsing W UMA binaries CSS J071813.2+505000, NSVS 2459652, NSVS 7178717 and NSVS 7377875. Rev. mex. astron. astrofis [online]. 2017, vol.53, n.1, pp.133-140. ISSN 0185-1101.

Photometric observations in Sloan g’ and i’ bands of four eclipsing W UMa binaries are presented. They allowed the improvement of system ephemerides. The light curve solutions led to the following results: (i) CSS J071813.2+505000 is barely an overcontact system, NSVS 2459652 and NSVS 7377875 are over-contact binaries with an intermediate fillout factor, while NSVS 7178717 has a deep-contact configuration; (ii) NSVS 7178717 undergoes total eclipses while the other three targets exhibit partial eclipses; (iii) The components of each target are almost the same in temperature: those of CSS J071813.2+505000 are early G stars while those of the other three targets are of K spectral type; (iv) The targets with late components reveal spot activity; (v) NSVS 2459652 and NSVS 7377875 are W UMa binaries of H subtype; (vi) The relation mass ratio - luminosity ratio of our targets confirms the results from previous statistical analysis of W UMa systems.

Palavras-chave : binaries: eclipsing - stars: fundamental parameters - stars:; individual (CSS J071813.2+505000; NSVS 2459652; NSVS 7178717; NSVS 7377875).