Investigating eclipse timing variations. The case study V471 Tau.

Several eclipsing binary systems display periodic eclipse timing variations (ETVs) when considering a linear ephemeris to predict the time of mid-eclipse. It is estimated that around 90 per cent of the post-common-envelope binary systems display ETVs. Observations of the eclipsing binary system V471 Tau show that the time of the primary eclipses varies in an apparent periodic way. There is growing evidence that the magnetically active K2 dwarf component might be responsible for driving the ETVs. The aim of our study is to monitor the star throughout the predicted magnetic activity cycle that putatively fuels the observed ETVs