Authors
René Liseau, PF Goldsmith, Bengt Larsson, L Pagani, Per Bergman, J Le Bourlot, TA Bell, AO Benz, EA Bergin, Per Bjerkeli, John H Black, S Bruderer, P Caselli, E Caux, J-H Chen, M De Luca, P Encrenaz, E Falgarone, M Gerin, JR Goicoechea, Åke Hjalmarson, DJ Hollenbach, Kay Justtanont, MJ Kaufman, F Le Petit, D Li, DC Lis, GJ Melnick, Z Nagy, AOH Olofsson, Göran Olofsson, E Roueff, Aa Sandqvist, RL Snell, FFS van der Tak, EF Van Dishoeck, C Vastel, S Viti, UA Yıldız
Publication date
2012/5/1
Journal
Astronomy & Astrophysics
Volume
541
Pages
A73
Publisher
EDP Sciences
Description
Context
Models of pure gas-phase chemistry in well-shielded regions of molecular clouds predict relatively high levels of molecular oxygen, O2, and water, H2O. These high abundances imply high cooling rates, leading to relatively short timescales for the evolution of gravitationally unstable dense cores, forming stars and planets. Contrary to expectations, the dedicated space missions SWAS and Odin typically found only very small amounts of water vapour and essentially no O2 in the dense star-forming interstellar medium.
Aims
Only toward ρ Oph A did Odin detect a very weak line of O2 at 119 GHz in a beam of size 10 arcmin. The line emission of related molecules changes on angular scales of the order of some tens of arcseconds, requiring a larger telescope aperture such as that of the Herschel Space Observatory to resolve the O2 emission and pinpoint its origin.
Methods
We use the Heterodyne …
Scholar articles
R Liseau, PF Goldsmith, B Larsson, L Pagani… - Astronomy & Astrophysics, 2012