Abstract
Both tunneling and Feshbach resonances occur near the second dissociation threshold of . There are three channels, , , and , which correlate to the , , and states, respectively. For the 2pπC state, there is a potential barrier near the dissociation limit, which accommodates bound states with energies above the threshold. The tunneling dissociation results in , while Feshbach resonances produce or . We measured the rotationally resolved spectra and determined the corresponding spectroscopic parameters. To study the dissociation dynamics, the spin-orbit branching ratios, and the fragment anisotropy parameters along the line profiles have been measured by a combination of Rydberg state ionization, velocity map ion imaging, and delay-time-curve methods. For the predissociation of the state with fragment kinetic energy of , only the fragment was observed. For the state with fragment kinetic energy of , the branching ratio between and was found to be close to the diabatic limit, and the predissociation should occur via tunneling and coupling with a triplet state near the dissociation limit. For the state, the predissociation should occur via tunneling, and coupling with the and states.
6 More- Received 29 May 2022
- Accepted 12 July 2022
DOI:https://doi.org/10.1103/PhysRevA.106.012824
©2022 American Physical Society