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arXiv · 2407.21117

The Nature of the Emission Spectrum of NGC 7793 P13: modeling the atmosphere of the donor star

A. S. Vinokurov·A. E. Kostenkov·K. E. Atapin·Yu. N. Solovyeva
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Abstract

We continue to study the ultra-luminous X-ray source NGC 7793 P13 in the optical range. In this work, we are testing the model of a spherically symmetric wind atmosphere of the donor star, previously identified as a B9 Ia supergiant. The model spectrum has shown good agreement with the observed one at a relatively high mass loss rate of $\dot{M} \approx 6\times10^{-6}\,M_{\odot}\,\text{yr}^{-1}$; other parameters turned out to be close to those expected for late B-supergiants. The increased mass loss rate can be explained by the high rotation velocity of the star. In addition, we have qualitatively demonstrated the effect of X-ray irradiation on the observed spectrum and discuss the fundamental possibility of wind acceleration under conditions of powerful irradiation.

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A. S. Vinokurov, A. E. Kostenkov, K. E. Atapin, Yu. N. Solovyeva. 2024-07-30. The Nature of the Emission Spectrum of NGC 7793 P13: modeling the atmosphere of the donor star. https://arxiv.org/abs/2407.21117

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