Changes in the period of the eclipsing system AH Virginis

Guthnick and Prager (1929) discovered the variability of AH Virginis. On the basis of later observations, AH Virginis was classified as one of the few W UMa systems which display complete eclipses at an inclination likely to be closer to 90 deg than to 61 deg. Observations made in connection with the present study confirm constancy of light of 40 minutes duration during primary minimum. The present observations indicate curved as well as flat secondary minima. The variable was observed photoelectrically in yellow light with the 38-cm reflector during one night in April and five nights in May, 1981. A total of 73 observations defining primary minimum (ingress and egress), and 66 observations defining secondary minimum was obtained.