The physical and chemical structure of hot molecular cores

• Published in: Astronomy and astrophysics (Berlin) 2004-02, Vol.414 (2), p.409-423
• Main Authors: Nomura, H., Millar, T. J.
• Format: Article
• Language: English
• Subjects: Astronomy; Earth, ocean, space; Exact sciences and technology; Fundamental aspects of astrophysics; Fundamental astronomy and astrophysics. Instrumentation, techniques, and astronomical observations; Interstellar medium (ism) and nebulae in milky way; ISM: individual objects: G34.3+0.15; Molecular and chemical processes and interactions; Molecular clouds, h2 clouds, dense clouds, and dark clouds; molecular processes; radiative transfer; stars: formation; Stellar systems. Galactic and extragalactic objects and systems. The universe
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361:20031646

We have made self-consistent models of the density and temperature profiles of the gas and dust surrounding embedded luminous objects using a detailed radiative transfer model together with observations of the spectral energy distribution of hot molecular cores. Using these profiles we have investigated the hot core chemistry which results when grain mantles are evaporated, taking into account the different binding energies of the mantle molecules, as well a model in which we assume that all molecules are embedded in water ice and have a common binding energy. We find that most of the resulting column densities are consistent with those observed toward the hot core G34.3+0.15 at a time around 104 years after central luminous star formation. We have also investigated the dependence of the chemical structure on the density profile which suggests an observational possibility of constraining density profiles from determination of the source sizes of line emission from desorbed molecules.