Discovery of Interstellar Propylene (CH2CHCH3): Missing Links in Interstellar Gas-Phase Chemistry

  title={Discovery of Interstellar Propylene (CH2CHCH3): Missing Links in Interstellar Gas-Phase Chemistry},
  author={N. Marcelino and Jos{\'e} Cernicharo and Marcelino Ag{\'u}ndez and {\`E}velyne Roueff and Maryvonne Gerin and Jes{\'u}s Mart{\'i}n-Pintado and Rainer Mauersberger and Clemens Thum},
  journal={The Astrophysical Journal Letters},
  pages={L127 - L130}
We report the discovery of propylene (also called propene, CH2CHCH 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, six 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 × 1013 cm-2, which corresponds to an… 

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