State-selective quantum interference observed in the photorecombination of Hg75+…78+ ions at the Heidelberg EBIT

The well-known Fano-profiles appearing in differential photonionization cross sections when resonances are present can also be observed in the time-reversed process of photorecombination of highly charged ions, where direct and indirect processes leading to the same final quantum state of the ion and the photon field can interfere, thus producing asymmetric lines shapes. Experiments performed at the Heidelberg electron beam ion trap with Hg75+…78+ ions have delivered state-selective Fano parameters and accurate resonance energies.