We study the kinematics of T Tauri stars (TTS) located in the
cores of the Chamaeleon clouds as well as far off these clouds. Our
sample comprises 2 early type stars known to be related to
Cha I , 6 classical (CTTS) and 6 weak-line
T Tauri stars (WTTS) known before the ROSAT mission, and 8
bona-fide pre-main sequence (PMS) stars as well as 23 presumably older
stars discovered with ROSAT (Alcalá et al. 1995; Covino et al.
1997). Altogether we present proper motions for 45 stars, taken
from the Hipparcos, ACT and STARNET catalogues. For 12 stars of
our sample parallaxes measured by Hipparcos are available, and we use
them to derive constraints on the distance distribution of the other
stars in our sample. Our analysis of the proper motions allows us to
divide the sample into several subgroups.
We analyse the motions of the stars in connection with different star formation scenarios and find them consistent with both the high velocity cloud (HVC) impact model (Lépine & Duvert 1994) and the cloudlet model (Feigelson 1996), whereas the data seem to be inconsistent with any kind of a dynamical ejection model.
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