The blue straggler S 1082: A triple system in the old open cluster M 67*
Astronomical Institute, Utrecht University, PO Box 80000, 3508 TA Utrecht, The Netherlands
2 Department of Astronomy, University of Wisconsin-Madison, 475 N Charter St, Madison WI 53706, USA
Corresponding author: M. van den Berg, firstname.lastname@example.org
Accepted: 9 March 2001
We present a photometric and spectroscopic study of the blue straggler S 1082 in the open cluster M 67. Our observations confirm the previously reported 1.07 day eclipse light curve and the absence of large radial-velocity variations of the narrow-lined star. However, we find two more spectral components which do vary on the 1.07 day period. We conclude that the system is triple. We fit the light and radial-velocity curves and find that the total mass of the inner binary is more than twice the turnoff mass and that the outer companion to the binary is a blue straggler on its own account. We briefly discuss formation scenarios for this multiple system.
Key words: binaries: eclipsing / binaries: spectroscopic / blue stragglers / stars: individual: S 1082 / open clusters and associations: individual: M 67
Based on observations made with the William Herschel Telescope, the Isaac Newton Telescope and the Jacobus Kapteyn Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, and the Dutch Telescope operated at La Silla by the European Southern Observatory.
© ESO, 2001