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The character of accretion and stellar wind parameters of T Tauri stars.






Alexandra Kravtsova (Sternberg Astronomical Institute, Moscow)

Lamzin S.A. (Sternberg Astronomical Institute, Moscow)





Quantitative parameters of disk wind were derived from the analysis of optical and UV spectra of CTTS. We found the matter outflows from a disk region with an outer radius of < 0.5 AU. The outflowing matter initially moves almost along the disk until being accelerated up to V> 100 km/s and only afterwards begins to collimate. Inner region of the wind is collimated into the jet at a distance <3 AU. from the disk mid plain. The Vz gas velocity component in the jet decreases with increasing distance from the jet axis. The gas temperature in the jet bottom is less then 20.000 K.

We found that the main portion of emission continuum of CTTS is formed outside the accretion shock, what means a great deal of accretion matter falls onto the star in nearly horizontal direction. This gas decelerate in turbulent layer near the star surface. We suggest two scenarios to explain such nature of accretion: two-stream accretion (through boundary layer and magnetosphere) and magnetospheric accretion by way of streams, the bulk of matter in which falls onto the star in nearly horizontal direction.





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