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arXiv · 2210.15163

Asteroseismology of PG 1541$+$651 and BPM 31594 with TESS

Alejandra D. Romero·Gabriela Oliveira da Rosa·S. O. Kepler·Paul A. Bradley·Murat Uzundag·Keaton J. Bell·J. J. Hermes·G. R. Lauffer
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Abstract

We present the photometric data from TESS for two known ZZ Ceti stars, PG 1541+651 and BPM 31594. Before TESS, both objects only had observations from short runs from ground-based facilities, with three and one period detected, respectively. The TESS data allowed the detection of multiple periodicities, 12 for PG 1541$+$651, and six for BPM 31594, which enables us to perform a detailed asteroseismological study. For both objects we found a representative asteroseismic model with canonical stellar mass ~ 0.61 Msun and thick hydrogen envelopes, thicker than 10^(-5.3) M_*. The detection of triplets in the Fourier transform also allowed us to estimate mean rotation periods, being ~22 h for PG 1541+651 and 11.6 h for BPM 31594, which is consistent with range of values reported for other ZZ Ceti stars.

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Alejandra D. Romero, Gabriela Oliveira da Rosa, S. O. Kepler, Paul A. Bradley, Murat Uzundag, Keaton J. Bell, J. J. Hermes, G. R. Lauffer. 2022-10-27. Asteroseismology of PG 1541$+$651 and BPM 31594 with TESS. https://doi.org/10.1093/mnras%2Fstac3113

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