We present the photometric and spectroscopic analysis of five W Uma type contact binaries. The studied targets are selected from the CRTS catalog. The photometric data is collected using the 1.3-m Devasthal Fast Optical Telescope (DFOT) and 1.04-m Sampurnanand Telescope (ST). We use the PHOEBE-legacy code for light curve modeling. The temperature is determined using different color-temperature relations. Due to the absence of multi-epoch radial velocity data, a photometric mass ratio is used for model fitting. Archival data from SuperWASP, CRTS, ASAS-SN, Kepler, and TESS is used for O-C period analysis. A long-term period study can give additional information about the presence of the third body, probable mass transfer rates, magnetic activity cycle, etc. Due to the presence of a third body, the O-C time of minima (TOM) observed at different cycles shows cyclic behavior. In the case of mass transfer only, the O-C of TOMs is a curve and it is a straight line for systems having a constant period. The linear and quadratic ephemeris are updated for all the targets. Some sources show a change in an orbital period which is explained on the basis of mass transfer between components.
The speaker is a senior research fellow (SRF) at ARIES. This is a paper acceptance talk.