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One of the predicitons of the ejection scenario is that the disks around
ejected brown dwarfs should have very small sizes and thus shorter life times
compared to their TTauri counterparts. In our study we start to explore this
prediction quantitatively by carrying out the first systematic study of disk
collisions in decaying triple systems. These results are then applied to
decaying accreting triple systems producing the browns dwarf binary
properties that are consistent with current observations. We found that the
collisions in those triple systems severely truncate the resulting disks down
to radii of the order of 1AU. However, in order to compare these disks to
disks around TTauri stars we have to take into account their further viscous
evolution to match the age of typical TTauri stars. By assuming a marginally
gravitationally stable disk before the last triple encounter we find that the
initially very small disks around ejected brown dwarfs expand to sizes
comparable to disks around TTauri stars while their life times are compatible
to accretor disk fractions derived for brown dwarfs from recent observations
for several star-forming regions. These fractions in turn are similar to
accretor disk fractions of TTauri stars. On the other hand we also find that
the life times of our truncated disks do not greatly exceed 5Myr, which seems
to contradict disk detections around brown dwarfs with ages of about 8 to
10Myr. We conclude that close collisions alone are currently not sufficient
to arrive at differences in disk size and life-time between disks around
brown dwarfs and TTauri stars, with the exception of a very few cases.
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