Previous abstract Next abstract
Session 25 - Stellar Winds, Accretion, & Molecular Clouds.
Oral session, Monday, January 15
La Condesa, Hilton
To better understand dense molecular cloud cores and to facilitate testing of existing chemical models, we have constructed a detailed model of these regions. In our model, we consider gas-phase chemistry (via the UMIST network), self-consistent dust continuum radiative transfer and dust temperature determination, and thermal balance of the gas (including gas-grain heating, and line cooling).
>From these data, we self-consistently solve the multi-level, NLTE line transfer problem including the dust continuum processes. The line transfer is solved for the species ^12C^16O, ^12C^18O, ^13C^16O, ^16OI, ^18OI, ortho-H_2^16O, ortho-H_2^18O, para-H_2^16O, amp; para-H_2^18O. In particular, we obtain water and oxygen line strengths and profiles, which can be used for comparison with observations from SWAS and ISO.
Among our results, we find that although the gas temperature follows the dust temperature in the inner regions of the core, the increasing transparency of the cooling transitions causes the gas temperature to deviate significantly below the dust temperature near the edge. Also, we find that the infrared pumping of the molecular lines by dust radiation is important, especially near the point of thermalization.
Program listing for Monday