Temperature Dependent Product Yields for the Spin Forbidden Singlet Channel of the C(3P) + C2H2 Reaction

TL;DR

This study measures how temperature affects the formation of hydrogen atoms in the C + C2H2 reaction, revealing insights relevant to interstellar chemistry and molecular abundances.

Contribution

It provides new temperature-dependent product yield data for the C + C2H2 reaction using laser-induced fluorescence, enhancing astrochemical models.

Findings

Hydrogen atom yields vary with temperature from 52 K to 296 K.

Results align with previous crossed beam experiments.

Incorporating yields into models affects interstellar molecule abundances.

Abstract

The atomic hydrogen formation channels of the C + C2H2 reaction have been investigated using a continuous supersonic flow reactor over the 52 K 296 K temperature range. H-atoms were detected directly at 121.567 nm by vacuum ultraviolet laser induced fluorescence. Absolute H-atom yields were determined by comparison with the H-atom signal generated by the C + C2H4 reaction. The product yields agree with earlier crossed beam experiments employing universal detection methods. Incorporating these branching ratios in a gas-grain model of dense interstellar clouds increases the cC3H abundance. This reaction is a minor source of C3 containing molecules in the present simulations.