Classical T Tauri Stars and Substellar Analogs

Classification Based on Empirical Criteria
  • D. Barrado Y Navascués
  • E. L. Martín
  • R. Jayawardhana
  • S. Mohanty


We propose a spectroscopic criterion based on Hα equivalent width and spectral type to classify classical T Tauri stars and substellar analogs. We argue that accreting objects can be identified from low-resolution optical spectroscopy, when their Hα flux is stronger than the saturation limit at Log {Lum(Hα)/Lum(bol)} = −3.3. Additional criteria, such as the relation between HeI5876 or HeI6678 and Hα, or the ratios between the components of the CaII infrared triplet, are also discussed. We have tested the reliability of these criteria by applying them to several objects with masses in the range 0.11–0.025 M, which belong to nearby star forming regions and the TW Hya association.


classical T Tauri brown dwarfs 


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Copyright information

© Springer Science+Business Media Dordrecht 2004

Authors and Affiliations

  • D. Barrado Y Navascués
    • 1
  • E. L. Martín
    • 2
  • R. Jayawardhana
    • 3
  • S. Mohanty
    • 4
  1. 1.Laboratorio de Astrofísica Espacial y Física Fundamental (LAEFF-INTA)MadridSpain
  2. 2.Institute for AstronomyUniversity of HawaiiUSA
  3. 3.Department of AstronomyUniversity of MichiganUSA
  4. 4.Harvard-Smithsonian Center for AstrophysicsCambridgeUSA

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