Erick Nagel, Catherine Espaillat, Paola D'Alessio, Nuria Calvet
CS Cha is a binary system surrounded by a circumbinary disk. We construct a
model for the inner disk regions and compare the resulting synthetic SED with
IRS spectra of CS Cha taken at two different epochs. For our model we adopt a
non-axisymmetric mass distribution from results of published numerical
simulations of the interaction between a circumbinary disk and a binary system,
where each star is surrounded by a disk. In particular, we approximate the
streams of mass from which the inner circumstellar disks accrete from the
circumbinary disk. This structure is due to the gravitational interaction of
the stars with the disk, in which an array of disks and streams are formed in
an inner hole. We calculate the temperature distribution of the optically thin
dust in these inner regions considering the variable impinging radiation from
both stars and use the observations to estimate the mass variations in the
streams. We find that the SEDs for both epochs can be explained with emission
from an optically thick inner edge of the circumbinary disk and from the
optically thin streams that connect the circumbinary disk with the two smaller
circumstellar disks. To the best of our knowledge, this is the first time that
the emission from the optically thin material in the hole, suggested by the
theory, is tested against observations of a binary system.
View original:
http://arxiv.org/abs/1201.4164
No comments:
Post a Comment