stars: early-type; stars: binaries: spectroscopic; stars: individual: HD 15570; stars: individual: HD 15629; stars: individual: HD 15558
Abstract :
[en] 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 components. These measurements were used to compute orbital solutions for HD 15558.
Results: .For HD 15570 and HD 15629, the radial velocities do not present any significant trend attributable to a binary motion on time scales of a few days, nor from one year to the next. In the case of HD 15558 we obtained an improved SB1 orbital solution with a period of about 442 days, and we report for the first time on the detection of the spectral signature of its secondary star. We derive spectral types O5.5III(f) and O7V for the primary and the secondary of HD 15558. We tentatively compute a first SB2 orbital solution although the radial velocities from the secondary star should be considered with caution. The mass ratio is rather high, i.e. about 3, and leads to very extreme minimum masses, in particular for the primary object. Minimum masses of the order of 150 ± 50 and 50 ± 15 M_ȯ are found respectively for the primary and the secondary.
Conclusions: .We propose that HD 15558 could be a triple system. This scenario could help to reconcile the very large minimum mass derived for the primary object with its spectral type. In addition, considering new and previously published results, we find that the binary frequency among O-stars in IC 1805 has a lower limit of 20%, and that previously published values (80%) are probably overestimated.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
De Becker, Michaël ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Sciences spatiales
Rauw, Grégor ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE) - Sciences spatiales
Manfroid, Jean ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Département d'astrophys., géophysique et océanographie (AGO)
Eenens, Philippe; Universidad de Guanajuato (Mexico) > Departamento de Astronomia
Language :
English
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
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Bibliography
Appenzeller, I. 1987, in Instabilities in Luminous Early Type Stars, ASSL, 136, 55
Bagnuolo, W. G., Gies, D. R., Riddle, R., & Penny, L. R. 1999, ApJ, 527, 353
Baranne, A., Queloz, D., Mayor, M., et al. 1996, A&AS, 119, 373
Bonanos, A. Z., Stanek, K. Z., Udalski, A., et al. 2004, ApJ, 611, L33
Bonnell, I. A., & Bate, M. R. 2002, MNRAS, 336, 659
Conti, P. S., Leep, E. M., & Lorre, J. J. 1977, ApJ, 214, 759
De Becker, M. 2005, Ph.D. Thesis, University of Liège
De Becker, M., Rauw, G., & Manfroid, J. 2004, A&A, 424, L39
Eggleton, P. P. 1983, ApJ, 268, 368
Feinstein, A., Vazquez, R. A., & Benvenuto, O. G. 1986, A&A, 159, 223
Figer, D. F., Najarro, F., Morris, M., et al. 1998, ApJ, 506, 384
García, B., & Mermilliod, J. C. 2001, A&A, 368, 122
Garmany, C. D., & Massey, P. 1981, PASP, 93, 500
Gillet, D., Burnage, R., Kohler, D., et al. 1994, A&AS, 108, 181
Schaerer, D., Meynet, G., Maeder, A., & Schaller, G. 1993, A&AS, 98, 523
Schaller, G., Schaerer, D., Meynet, G., & Maeder, A. 1992, A&AS, 96, 269
Shi, H. M., & Hu, J. Y. 1999, A&AS, 136, 313
Underhill, A. B. 1967, in IAU Symp. 30: Determination of Radial Velocities and their Applications, 167
Vasilevskis, S., Sanders, W. L., & van Altena, W. F. 1965, AJ, 70, 806
Walborn, N. 2001, in Eta Carinae and Other Mysterious Stars: The Hidden Opportunities of Emission Spectroscopy, ASP Conf. Ser., 242, 217
Walborn, N. R. 1972, AJ, 77, 312
Walborn, N. R., & Fitzpatrick, E. L. 1990, PASP, 102, 379
Werner, K., & Rauch, T. 2001, in Eta Carinae and Other Mysterious Stars: The Hidden Opportunities of Emission Spectroscopy, ASP Conf. Ser., 242, 229
Wolfe, R. H., Horak, H. G., & Storer, N. W. 1967, The machine computation of spectroscopic binary elements (Modern astrophysics. A memorial to Otto Struve), 251
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