Charge-encoded multi-photoion coincidence for three-body fragmentation of CO₂ in the strong laser fields

The photoion-photoion coincidence (PIPICO) is a simple and effective approach for the selection of correlated fragments in a specific dissociating channel in molecules. We propose here a charge-encoded multi-photoion coincidence (cMUPICO) method, in analogy to traditional PIPICO, however in which the charge of individual fragments is taken into account. The cMUPICO method allows for clearly displaying coincident channels for dissociation channels containing three more fragments with unequal charge states, invisible in the traditional PIPICO. As a demonstration, three-body fragmentation dynamics of CO₂ in strong IR laser fields is analyzed, and 11 dissociation channels are effectively identified, five of which are first found with cMUPICO. The present results show that cMUPICO is a powerful and practical tool for distinguishing various dissociation channels with multiply charged multi-photoions.