The eclipsing γ Doradus star V421 Pegasi

Abstract We present high-precision TESS photometry of V421 Pegasi (V421 Peg, TIC 301747091), an early F-type eclipsing binary containing a candidate $\gamma$ Doradus ($\gamma$ Dor) component. The observed short-cadence data allow the detection of pulsation signals, along with revision of the fundamental properties of the component stars. Detailed binary modeling indicated that the program target is a partially eclipsing detached system in a circular orbit and that both components are currently in super-synchronous states. The radii of each star were measured with an accuracy of about 1%. By periodogram analysis of the outside-eclipse residual lights obtained from the binary star model, we extracted nine significant signals, five of which are likely aliasing frequencies due to sampling artifacts and uncorrected trends in the data used. The other signals of $f_1$, $f_2$, $f_3$, and $f_6$ are considered to be independent pulsations with frequencies ranging from 0.73 to 1.02 d$^{-1}$, corresponding to pulsation constants of 0.63–0.88 d. These frequencies, pulsation constants, and position on the Hertzsprung–Russell diagram reveal that the pulsating signals are $\gamma$ Dor variables arising from the V421 Peg primary component.