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arXiv · 2402.14378

Luminosity class of the symbiotic stars 4U1954+319 and ZZ CMi

R. Zamanov·K. A. Stoyanov·G. Latev·J. Marti·A. Takey·E. G. Elhosseiny·M. D. Christova·M. Minev·V. Vujcic·M. Moyseev·V. Marchev
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Abstract

We performed optical photometry and spectral observations of the symbiotic stars 4U1954+319 and ZZ CMi. For 4U1954+319 using high-resolution spectra we measure the equivalent widths of diffuse interstellar bands and estimate the interstellar reddening E(B-V)=0.83 +/- 0.09. Using GAIA distances and our photometry, we find (1) absolute V band magnitude of 4U1954+319 M_V=-5.23 +/- 0.08 and that the mass donor is a supergiant of luminosity class Ib, and (2) for ZZ CMi M_V=-0.27 +/- 0.2 and that the mass donor is a giant of luminosity class III.

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R. Zamanov, K. A. Stoyanov, G. Latev, J. Marti, A. Takey, E. G. Elhosseiny, M. D. Christova, M. Minev, V. Vujcic, M. Moyseev, V. Marchev. 2024-02-22. Luminosity class of the symbiotic stars 4U1954+319 and ZZ CMi. https://arxiv.org/abs/2402.14378

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