Tom J. G. Wilson

S. Matt,
T.J. Harries



  • We compare hydrogen emission from 29 T Tauri stars with a grid 945 of synthetic line profiles.

  • Our synthetic line profiles match the observed H⍺ widths, intensities and profile morphologies.

  • However, our study indicates that reproducing H⍺, Paschen, and Brackett lines simultaneously is problematic. The synthetic infrared lines are too narrow and exhibit a higher than observed frequency of Inverse P-Cygni profiles.

Stellar wind

Radiative Transfer Model - TORUS1

  • Synthetic line profile computed using the radiative transfer code TORUS.


  • Figure shows spectra of 29 T Tauri stars (columns) from the ESO Archive[2]. The Stars are ordered by H⍺ intensity.

  • Medium resolution (R~11600-18400) spectra from VLT’s X-Shooter, observed in Jan 2010.

  • Near simultaneous observations of H⍺ (6562 Å), Pa𝛾 (10938 Å), Paβ (12818 Å), and Br𝛾 (21655 Å).

  • A correlation of structure and intensity is seen between the infrared lines, this is not reflected by H⍺
Line profiles


  • Figure shows the FWHM vs. half width at 10% maxima (HW10%). Models are clipped so that H⍺ matches the observed HW10% range.

  • Synthetic H⍺ lines reproduce well the observed range of widths and distribution of Reipurth types[3].

  • The same models produce Pa𝛾, Paβ, and Br𝛾 lines ~70-100 kms-1 too narrow.

  • Over 80% of the synthetic Pa𝛾, Paβ, and Br𝛾 lines exhibit Inverse P-Cygni profiles.