A new desorption mechanism for condensed phase interstellar CO

Abstract

view Abstract Citations (14) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A New Desorption Mechanism for Condensed Phase Interstellar CO Dzegilenko, Fedor ; Herbst, Eric Abstract We have shown previously that weakly bound CO can be desorbed from both ice and hydrated silica (SiO2 with surface water molecules) by a novel mechanism in which (1) a neighboring OH group is excited to its v = 1 vibrational state and (b) the energy is transferred via a dipole-dipole interaction to CO, where at least part of it is stored in the librational-physisorption modes of the adsorbed molecule, leading to desorption on a short timescale. In this Letter, we utilize the results of our previous work to estimate the desorption rate of CO from hydrated silica grains via this mechanism in dense interstellar clouds. The rate is estimated to be sufficiently rapid to keep a large percentage of CO off grains with polar (water ice-dominated) mantles. One uncertainty in the rate determination derives from an uncertainty in the proper infrared flux at 3.05 micrometers. Publication: The Astrophysical Journal Pub Date: April 1995 DOI: 10.1086/187841 Bibcode: 1995ApJ...443L..81D Keywords: Carbon Monoxide; Cosmic Dust; Desorption; Ice; Interstellar Gas; Molecular Clouds; Molecular Interactions; Silicon Dioxide; Dipole Moments; Flux Density; Hydroxyl Radicals; Vibrational States; Astrophysics; ISM: DUST; EXTINCTION; ISM: MOLECULES; MOLECULAR PROCESSES full text sources ADS |