Early-type stars in the young open cluster IC 1805. II. The probably single stars HD 15570 and HD 15629, and the massive binary/triple system HD 15558

  title={Early-type stars in the young open cluster IC 1805. II. The probably single stars HD 15570 and HD 15629, and the massive binary/triple system HD 15558},
  author={Micha{\"e}l De Becker and Gregor Rauw and Jean Manfroid and Philippe R. J. Eenens},
  journal={Astronomy and Astrophysics},
Aims. We address the issue of the multiplicity of the three brightest early-type stars of the young open cluster IC 1805, namely HD 15570, HD 15629 and HD 15558. Methods. For the three stars, we measured the radial velocity by fitting Gaussian curves to line profiles in the optical domain. In the case of the massive binary HD 15558, we also used a spectral disentangling method to separate the spectra of the primary and of the secondary in order to derive the radial velocities of the two… 
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