B. Riaz, G. Lodato, D. Stamatellos, J. E. Gizis
We present Herschel/SPIRE observations for the 2MASS1207334-393254 (2M1207)
system. Based on radiative transfer modeling of near-infrared to sub-millimeter
data, we estimate a disc mass of 3+/-2 M_Jup and an outer disc radius of
50--100 AU for the 2M1207A disc. The relative disc mass for 2M1207A is similar
to the T Tauri star TW Hya, which indicates that massive discs are not
underabundant around sub-stellar objects. In probing the various formation
mechanisms for this system, we find that core accretion is highly uncertain
mainly due to the large separation between the primary and the companion. Disk
fragmentation could be a likely scenario based on analytical models, and if the
disc initially was more massive than its current estimate. Considering that the
TWA is sparsely populated, this system could have formed via one of the known
binary formation mechanisms (e.g. turbulent fragmentation of a core) and
survived disruption at an early stage.
View original:
http://arxiv.org/abs/1201.4173
No comments:
Post a Comment