Spatially resolved spectroscopy of infrared companions to T Tauri stars

Evidence for Ongoing Accretion
  • T. M. Herbst
  • C. D. Koresko
  • Christoph Leinert
Part I: Disks—Observation
Part of the Lecture Notes in Physics book series (LNP, volume 465)


We describe the technique of spatially resolved spectroscopy of close binary stars and present K band spectra of the Haro 6-10 and UY Aur infrared companion (IRC) systems. The IRC’s are characterized by very low infrared colour temperature and high luminosity. Our observations address the debate between those who suggest that the IRC’s are at an earlier evolutionary stage than their primary stars, and those who believe that these objects are relatively normal pre-main-sequence stars with substantial local extinction and accreting matter.

In both Haro 6-10 and UY Aur, we detect 2 μm molecular hydrogen emission confined to the infrared companions. The line ratios are consistent with shock heating, strengthening the view that the IRC’s are experiencing ongoing accretion. In the case of UY Aur, non-spherical geometry, such as accretion onto a circumstellar disk, can explain the presence of molecular hydrogen emission, low effective temperature, and high luminosity while allowing moderate extinction to the photosphere at near infrared wavelengths.


Molecular Hydrogen Spectral Type Line Flux Interstellar Extinction Tauri Star 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Beckwith, S., Gatley, I., Matthews, K., and Neugebauer, G. 1978, Ap. J. (Letters), 223, L41.CrossRefADSGoogle Scholar
  2. Bertout, C. 1983. Astr. Ap., 126, L1.ADSGoogle Scholar
  3. Bessel, M.S. and Brett, J.M. 1988, P. A. S. P., 100, 1134.CrossRefADSGoogle Scholar
  4. Bohlin, R.C., Savage, B.D., and Drake J.F. 1978, Ap. J., 224, 132.CrossRefADSGoogle Scholar
  5. Carr, J.S. 1989, Ap. J., 345, 522.CrossRefADSGoogle Scholar
  6. Carr, J.S. 1990, Astron. J., 100, 1244.CrossRefADSGoogle Scholar
  7. Chelli, A., Zinnecker, H., Carrasco, L., Cruz-Gonzales, I., and Perrier C. 1988, Astr. Ap., 207, 46.ADSGoogle Scholar
  8. Cohen, M. and Kuhi, L.V. 1979, Ap. J. Suppl., 41, 743.CrossRefADSGoogle Scholar
  9. Dyck, H.M., Simon, T., and Zuckerman, B. 1982. Ap. J. (Letters) 255, L103.CrossRefADSGoogle Scholar
  10. Ghez, A.M., Neugebauer, G., and Matthews, K. 1994. Astron. J., 106, 2005.CrossRefADSGoogle Scholar
  11. Ghez, A.M., Neugebauer, G., Gorham, P.W., Haniff C.A., Kulkarni, S.R., Matthews, K., Koresko, C., and Beckwith, S. 1991, Astron. J., 102, 2066.CrossRefADSGoogle Scholar
  12. Herbig, G.H. and Bell, K.R. 1988, Lick Obs. Bull. No. 1111.Google Scholar
  13. Herbst, T.M., and Koresko, C.D. 1991 (HK91). Unpublished data.Google Scholar
  14. Herbst, T.M., Beckwith, S.V.W., Birk, Ch., Hippler, S., McCaughrean, M.J., Mannucci, F., and Wolf, J. 1993, in: Infrared Detectors and Instrumentation SPIE Conference 1946Google Scholar
  15. Herbst, T. M. and Rayner, J.T. 1994a, in Infrared Arrays, The Next Generation. Ed.: McLean, J.S., Kluwer Acad. Publ., Dordrecht, p. 515Google Scholar
  16. Herbst, T.M., Pitz, E., and Reuther, C.M. 1994b, in Tridimensional Optical Spectroscopic Techniques in Astrophysics, I.A.U. Colloquium 149, in pressGoogle Scholar
  17. Herbst, T.M., Koresko, C.D., and Leinert, Ch. 1995, Ap. J. (Letters), 444, L93.CrossRefADSGoogle Scholar
  18. Joy, A.H. and van Biesbroeck, G. 1944, P. A. S. P., 56, 123.CrossRefADSGoogle Scholar
  19. Kleinmann, S.G. and Hall, D.N.B. 1986, Ap. J. Suppl., 62, 501.CrossRefADSGoogle Scholar
  20. Koresko, C.D. 1993, PhD. Thesis, Cornell University.Google Scholar
  21. Lançon, A. and Rocca-Volmerange, B. 1992, Astr. Ap. Suppl., 96, 593.ADSGoogle Scholar
  22. Leinert, Ch., and Haas, M. 1989, Ap. J. (Letters), 342, L39.CrossRefADSGoogle Scholar
  23. Leinert, Ch., Zinnecker, H., Weitzel, N., Christou, J., Ridgway, S.T., Jameson, R., Haas, M., and Lenzen, R. 1993, Astr. Ap., 278, 129.ADSGoogle Scholar
  24. Oliva, E., and Origlia, L. 1992, Astr. Ap., 254, 466.ADSGoogle Scholar
  25. Rieke, G. H., and Lebofsky, M.J. 1985, Ap. J., 288, 618.CrossRefADSGoogle Scholar
  26. Schmidt-Kaler, Th. 1982, in: Landolt-Börnstein Numerical Data and Functional Relationships in Science and Technology, Group 4, Vol. 2, Subvol. b, eds. K. Schaffers and H.H. Voigt, p. 451.Google Scholar
  27. Shull, J.M. and Beckwith, S. 1982, Ann. Rev. Astr. Ap., 20, 163.CrossRefADSGoogle Scholar
  28. Smith, M.D. 1995, A&A 296, 789ADSGoogle Scholar
  29. Zinnecker, H. 1989, in Low-Mass Star Formation and PMS Objects, ed. B. Reipurth.Google Scholar

Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  • T. M. Herbst
    • 1
  • C. D. Koresko
    • 2
  • Christoph Leinert
    • 1
  1. 1.Max-Planck-Institut für AstronomieHeidelbergGermany
  2. 2.Department of AstronomyUniversity of TexasAustinUSA

Personalised recommendations