Photofragmentation of CD₃⁺ driven by intense ultrashort laser pulses*

We investigate photofragmentation processes of CD₃⁺ by focusing intense ultrashort laser pulses^‡ onto a fast (keV) CD₃⁺ ion beam target. The use of an ion beam as a target allows for the direct position-and-time measurement of all ionic and neutral fragments, which we then use to calculate their 3-D momenta. Comparing the relative probabilities (branching ratios) of different photodissociation and photoionization processes is one of our main goals. However, contributions from a contaminant ion beam must be determined and subtracted. Also, the kinetic energy release (KER) and angular distributions of these processes are determined. It is worth noting that dissociation of CD₃²⁺ involves both charge-symmetric (CD₂⁺ + D⁺), i.e., deprotonation, and charge-asymmetric dissociation (CD₂²⁺ + D), i.e., hydrogen elimination.

^‡780-nm, 25-fs, ~10¹⁵-W/cm² laser pulses at 10 kHz