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arXiv · 1912.00405

Complex asteroseismology of SX Phoenicis

J. Daszyńska-Daszkiewicz·P. Walczak·A. Pamyatnykh·W. Szewczuk·W. Dziembowski
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Abstract

We present seismic analysis of the prototype SX Phoenicis that aims at fitting the two radial-mode frequencies and the corresponding values of the bolometric flux amplitude (the parameter $f$), whose empirical values are derived from multi-coulor photometric observations. Seismic model that meets these conditions is of low mass, $M=1.05 M_\odot$, has moderately effective convection in the outer layers, described by the mixing length parameter $\alpha_{\rm MLT} \approx 0.7$, and the microturbulent velocity in the atmospheres of about $\xi_{\rm t}\approx 8$km/s. Such seismic studies of stars like SX Phe are very important for deriving constraints on outer-layer convection, because the object is on the border between very effective and ineffective convection.

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J. Daszyńska-Daszkiewicz, P. Walczak, A. Pamyatnykh, W. Szewczuk, W. Dziembowski. 2019-12-01. Complex asteroseismology of SX Phoenicis. https://arxiv.org/abs/1912.00405

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