The orbital period variations of AH Virginis

We present a study of orbital period changes in AH Virginis. We perform a careful literature search for all available minima times, from which we derived a new linear ephemeris and constructed an O — C curve. We found that the orbital period of AH Virginis shows a long-term increase, dP/dt = (2.1869 ± 0.0161) × 10^-7 d yr^-1, and a small periodic variation with a period of 37.19 yr. Since AH Virginis is an over-contact system and the primary component shows strong Hα and Mg II emission lines, we discuss the possible connection between mass transfer, magnetic activity and orbital period changes.