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arXiv · 2112.05835

Ground-based observations of the ZZ Ceti star HS 1625+1231

Csilla Kalup·Zsófia Bognár·Ádám Sódor
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Abstract

We present the results of our detailed light curve analysis of the ZZ Ceti star HS 1625+1231. We collected photometric time series data at Konkoly Observatory on 14 nights, and performed Fourier analysis of these data sets. We detected 11 significant frequencies, where six of them are found to be independent pulsation modes in the 514 - 881 s period range. By utilising these frequencies, we performed preliminary asteroseismic investigations to give constraints on the main physical parameters, and to derive seismic distances for the star. Finally, we compared the astrometric distance provided by the Gaia EDR3 data with those seismic distances. Our selected model, considering both the spectroscopic measurements and the distance value provided by Gaia, has $T_{eff}$ = 11 000 K and $M_*$ = 0.60 $M_{\odot}$.

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Csilla Kalup, Zsófia Bognár, Ádám Sódor. 2021-12-10. Ground-based observations of the ZZ Ceti star HS 1625+1231. https://doi.org/10.32023/0001-5237%2F71.4.2

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