American Astronomical Society, Astrophysical Journal, 1(760), p. 9, 2012
DOI: 10.1088/0004-637x/760/1/9
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We develop an empirical model to estimate mass-loss rates via coronal mass ejections (CMEs) for solar-type pre-main-sequence (PMS) stars. Our method estimates the CME mass-loss rate from the observed energies of PMS X-ray flares, using our empirically determined relationship between solar X-ray flare energy and CME mass: log(M_CME [g]) = 0.63 x log(E_flare [erg]) - 2.57. Using masses determined for the largest flaring magnetic structures observed on PMS stars, we suggest that this solar-calibrated relationship may hold over 10 orders of magnitude in flare energy and 7 orders of magnitude in CME mass. The total CME mass-loss rate we calculate for typical solar-type PMS stars is in the range 1e-12 to 1e-9 M_sun/yr. We then use these CME mass-loss rate estimates to infer the attendant angular momentum loss leading up to the main sequence. Assuming the CME outflow rate for a typical ~1 M_sun T Tauri star is 1e-10 M_sun/yr, as permitted by our calculations, the CME spin-down torque may influence the stellar spin evolution after an age of a few Myr. ; Comment: 13 pages, 4 figures, accepted to the ApJ