A PROBABLE HYBRID γ DOR–δ SCUTI VARIABLE DISCOVERED IN THE OPEN CLUSTER NGC 2126

We have carried out high-precision B- and V-band time-series CCD photometry to investigate the physical nature of an oscillating EA-type binary system in the intermediate-age open cluster NGC 2126. Analysis of the light variability for about 500 stars in this field has led to the discovery of three new variables, two pulsating stars and one EA-type eclipsing binary. One of the former, GSC3382-0957, a probable cluster member, is shown to have both p- and g-mode pulsations. A frequency analysis reveals two confident pulsating modes at f sub(1) = 14.835 c/d and f sub(2) - 1.812 c/d from both the B- and V-band data. In the color-magnitude diagram, the star is located at the lower edge of the delta Scuti instability strip, where the delta Sct and gamma Dor stars overlap. It is suggested that this is a probable hybrid gamma Dor- delta Sct star.