In conjunction with the study of the reaction between O- and C2H2 performed using 22-pole RF ion trap, a relative amount of C2H2 in a commercial mixture of C2H2 and helium was determined. A continuous wave Cavity Ring-Down Spectroscopy technique was employed to monitor several absorption lines of H12C12CH and H13C12CH.
The obtained results enabled to lower the systematic error of the value of the measured reaction rate coefficient for the aforementioned reaction.