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Polarization in the Young Cluster NGC 6611: Circumstellar, Interstellar, or ... Both?

  • Pierre Bastien
  • François Ménard
  • Patrice Corporon
  • Nadine Manset
  • Frédérick Poidevin
  • Gaspard Duchêne
  • Jean-Louis Monin

Abstract

We obtained linear polarization observations of 82 A/B-type stars in the young cluster NGC 6611, in order to probe the circumstellar material and to search for any evidence of intracluster or interstellar material that could also contribute to the polarization. We found linear polarization values that reach up to 14%. We consider the distribution of the polarization, its position angle, correlations with extinction and membership probability, polarization variability and wavelength distribution to identify the origin of the polarization toward NGC 6611. The polarization is found to be dominated by interstellar polarization, although some stars also have some circumstellar polarization. There is no evidence for intracluster dust. Rather, the dust must be located in a low density cloud toward the general line of sight to NGC 6611 and in front of it. The depth of that cloud along the line of sight increases slowly from the south—east to the north—west. The cloud is threaded by a very uniform magnetic field.

Keywords

polarization stars: pre-main-sequence 

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References

  1. Arce, H.G., Goodman, A.A., Bastien, P., Manset, N. and Sumner, M.: 1998, Api 499, L93.ADSGoogle Scholar
  2. Belikov, A.N., Kharchenko, N.V., Piskunov, A.E. and Schilbach, E.: 1999, AandAS 134, 525.Google Scholar
  3. de Winter, D., Koulis, C., Thé, P.S., van den Ancker, M.E., Perez, M.R. and Bibo, E.A.: 1997, AandAS 121, 223.Google Scholar
  4. Hillenbrand, L.A., Massey, P., Strom, S.E. and Merill, K.M.: 1993, AJ 106, 1906. Manset, N. and Bastien, P.: 1995, PASP 107, 483.Google Scholar
  5. Ménard, F., Bastien, P., Montmerle, T. and Bertout, C.: 2004, in preparation. Myers, P. and Goodman, A.A.: 1991, ApJ 373, 509.Google Scholar
  6. Serkowski, K., Mathewson, D.L. and Ford, V.L.: 1975, Api 196, 261.ADSGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2004

Authors and Affiliations

  • Pierre Bastien
    • 1
  • François Ménard
    • 2
    • 3
  • Patrice Corporon
    • 1
  • Nadine Manset
    • 1
    • 3
  • Frédérick Poidevin
    • 1
  • Gaspard Duchêne
    • 4
  • Jean-Louis Monin
    • 2
  1. 1.Département de physique and Observatoire du mont MéganticUniversité de MontréalUSA
  2. 2.Laboratoire d’Astrophysique de l’Observatoire de GrenobleFrance
  3. 3.Canada-France-Hawaii Telescope CorporationUSA
  4. 4.Department of Physics and AstronomyUniversity of CaliforniaLos AngelesUSA

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