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arXiv · 2401.16226

A new catalog of magnetically active solar-like oscillators

Abstract

We present a new catalog of stars for which detected solar-like oscillations and magnetic activity measurements are both available from chromospheric spectroscopic observations. Our results were obtained by exploiting NASA TESS mission light curves for active stars observed within the Mount Wilson Observatory HK project and the HK survey of the Hamburg Robotic Telescope TIGRE. We analyzed the light curves for a total of 191 stars by adopting recent techniques based on Bayesian analysis and model comparison to assess the detection of a power excess originating from solar-like oscillations. We characterized the oscillations in a total of 34 targets, for which we provide estimates for the global asteroseismic parameters of $\nu_\mathrm{max}$ (the frequency of maximum oscillation power), $\Delta\nu$ (the large frequency separation), and for the amplitude of the solar-like oscillation envelope $A_\mathrm{max}$. We provide strong statistical evidence for the detection of solar-like oscillations in 15 stars of our sample, identify six further stars where a detection is likely, and 13 stars for which oscillations cannot be ruled out. The key parameters extracted in this work will be exploited for a detailed stellar modeling of the targets and to calibrate relations that connect the level of the measured magnetic activity to the suppression induced on the global oscillation amplitudes. This opens the possibility of shedding light on the interplay between magnetic fields and oscillations. Because of their relatively high brightness, the targets may also be of interest for future dedicated follow-up observations using both photometry and spectropolarimetry.

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BibTeXRIS

E. Corsaro, A. Bonanno, C. Kayhan, M. P. Di Mauro, R. Reda, L. Giovannelli. 2024-01-29. A new catalog of magnetically active solar-like oscillators. https://arxiv.org/abs/2401.16226

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