Discovery of Interstellar Propylene (CH 2 CHCH 3 ): Missing Links in Interstellar Gas-Phase Chemistry
- 10 August 2007
- journal article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 665 (2) , L127-L130
Abstract
We report the discovery of propylene (also called propene, CH_2CHCH_3) with the IRAM 30-m radio telescope toward the dark cloud TMC-1. Propylene is the most saturated hydrocarbon ever detected in space through radio astronomical techniques. In spite of its weak dipole moment, 6 doublets (A and E species) plus another line from the A species have been observed with main beam temperatures above 20 mK. The derived total column density of propylene is 4 10^13 cm^-2, which corresponds to an abundance relative to H_2 of 4 10^-9, i.e., comparable to that of other well known and abundant hydrocarbons in this cloud, such as c-C_3H_2. Although this isomer of C_3H_6 could play an important role in interstellar chemistry, it has been ignored by previous chemical models of dark clouds as there seems to be no obvious formation pathway in gas phase. The discovery of this species in a dark cloud indicates that a thorough analysis of the completeness of gas phase chemistry has to be done.Keywords
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This publication has 32 references indexed in Scilit:
- Non-thermal desorption from interstellar dust grains via exothermic surface reactionsAstronomy & Astrophysics, 2007
- A 8.8–50 GHz Complete Spectral Line Survey toward TMC-1 I. Survey DataPublications of the Astronomical Society of Japan, 2004
- A Spectral Line Survey of Selected 3 Millimeter Bands toward Sagittarius B2(N‐LMH) Using the National Radio Astronomy Observatory 12 Meter Radio Telescope and the Berkeley‐Illinois‐Maryland Association Array. I. The Observational DataThe Astrophysical Journal, 2004
- Rates and Products of the Dissociative Recombination of C3H7+ in Low-Energy Electron CollisionsThe Journal of Physical Chemistry A, 2003
- Small‐Scale Abundance Variations in TMC‐1: Dynamics and Hydrocarbon ChemistryThe Astrophysical Journal, 2001
- Molecular Carbon Chains and Rings in TMC‐1The Astrophysical Journal, 2001
- Chemical constraints and microstructure in TMC-1 Core DAstronomy & Astrophysics, 2001
- A λ2 mm molecular line survey of the C-star envelope IRC+10216Astronomy and Astrophysics Supplement Series, 2000
- Gas-phase production of complex hydrocarbons, cyanopolyynes, and related compounds in dense interstellar cloudsThe Astrophysical Journal Supplement Series, 1989
- A survey of the millimeter-wave spectrum of Sagittarius B2The Astrophysical Journal Supplement Series, 1986