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First spectra of the W UMa system V524 Monocerotis

T. H. Dall·L. Schmidtobreick
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Abstract

We present the first high-resolution spectra of the W UMa contact binary V524 Mon. The spectra of the two components are very similar, resembling a G5 and a K0. We find the radial velocities and rotational velocities consistent with corotation. We estimate the radii and the masses and derive a mass ratio M_2/M_1 = 2.1. We confirm that V524 Mon is a W-type contact system, likely enclosed in a common convective envelope, as found by Samec & Loflin (2003). We do not find evidence for the expected level of emission in the chromospheric CaII H and K lines, neither H_alpha, indicating that the magnetic activity is much weaker than expected or that other processes are hampering chromospheric emission.

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T. H. Dall, L. Schmidtobreick. 2004-09-09. First spectra of the W UMa system V524 Monocerotis. https://doi.org/10.1051/0004-6361%3A20041300

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