Nascent vibrational and rotational distributions of CH+ (A 1Π) produced from the charge transfer reaction of He+ with C2H2 at thermal energy

The CH+(A 1Π−X 1Σ+) emission has been observed from the He++C2H2 reaction at thermal energy under low pressure conditions. The nascent vibrational distribution for v′=0−3 was nearly exponential with a Boltzmann temperature of 2300±300 K. The nascent rotational temperature varied from 3000±500 K for v′=0 to 2000±1000 K for v′=3. The fractions of the available energy deposited into rotation 〈fr〉 and vibration 〈 fv〉 were evaluated to be 21% and 9%, respectively.