Cool Stars 14 - Submitted Abstract # 146
This version created on 05 October 2006

Modelling of Circumstellar Disks in low-mass Pre-Main-Sequence Stars:
A Case Study on RNO 91


Boddapati Anandarao, Physical Research Laboratory, Ahmedabad, India
Abhijit Chakraborty, Physical Research Laboratory, Ahmedabad, India
Lokesh Dewangan, Physical Research Laboratory, Ahmedabad, India

It is now believed that during their pre-main-sequence (PMS) stages,
stars of all masses exhibit manifestations such as disks and jets.  In
the past two decades, several cases of such manifestations have been
discovered in a large number of low mass PMS stars.  RNO 91 in L43 in
Ophiuchus star forming complex is one such example.  This M0.5 Class
II PMS star exhibits asymmetric molecular (CO and H2) jets and a large
(~ 1700  AU) disk with molecular ice features.  Based on these facts
it is quite reasonable to conjecture that the disk of this PMS star
could as well be a site for future planetary formation.  Earlier
observations suggested that the disk is tilted in the plane of the sky
and hence its asymmetric jets.  We present a model of the star and its
disk, using a numerical code that takes in to account the
re-processing of stellar light by the dust particles and viscous drag
that heats the disk, in order to account for the observed Spectral
Energy Distribution (SED) in the wavelength region of the visible -
far-infrared from archival data including the Spitzer-MIPS data.  Such
a modelling gives an insight into the physical conditions of various
contributing constituents - mainly the PMS star and its disk.  We
shall present these results as well as those for a few other young
Stellar Objects of low mass and discuss the physical parameters that
we obtained from the modelling.

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