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New Photometry of the Hyades $δ$ Scuti star V777 Tau (71 Tau)

Kevin Krisciunas·Theodore Simon·Richard A. Crowe·Mavourneen Roberts
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Abstract

71 Tau was discovered to be a $δ$ Scuti star by Horan (1979, AJ 84, 1770). To our knowledge no other photometry of this star has been published. 71 Tau is the second brightest X-ray source in the Hyades and has been shown to be variable by as much as 30 \% at ultraviolet wavelengths near 1700 to 2000 Å. We find that the best two-frequency fit to the new photometry is obtained with $f_{1}$ = 5.485 and $f_{2}$ = 7.637 d$^{-1}$, with amplitudes $A_{1}$ = 6.0 and $A_{2}$ = 3.4 mmag, respectively. However, one-day aliases of these frequencies {\em could} be the true values. (For $δ$ Scuti stars pulsating radially the ratio of first overtone period to fundamental period is 0.773.) It would be useful to obtain more extensive data runs on this and other $δ$ Scuti stars in the Hyades.

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Kevin Krisciunas, Theodore Simon, Richard A. Crowe, Mavourneen Roberts. 1995-11-21. New Photometry of the Hyades $δ$ Scuti star V777 Tau (71 Tau). https://arxiv.org/abs/astro-ph/9511094

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