Search for low-mass PMS companions around X-ray selected late B stars

  title={Search for low-mass PMS companions around X-ray selected late B stars},
  author={Swetlana Hubrig and David Le Mignant and Pierre L. North and J. Simmerer European Southern Observatory and Chile. and Laboratoire d'astrophysique and Observatoire de Grenoble and France. and W. M. Keck Observatory and Usa Institut d'Astronomie de l'Universite de Lausanne and Switzerland Landessternwarte Heidelberg-Koenigstuhl and H Germany},
  journal={Astronomy and Astrophysics},
We have observed 49 X-ray-detected bright late B-type dwarfs to search for close low-mass pre-main sequence (PMS) companions using the European Southern Observatory's ADONIS (Adaptive Optics Near Infrared System) instrument. We announce the discovery of 21 new companions in 9 binaries, 5 triple, 4 quadruple system and 1 system consisting of ve stars. The detected new companions have K magnitudes between 6: m 5a nd 17: 3 and angular separations ranging from 0: 00 2t o 14: 00 1 (18-2358 AU). 

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