Time-Resolved Multielectron Coincidence Spectroscopy of Double Auger-Meitner Decay Following Xe 4d Ionization

We introduce time-resolved multielectron coincidence spectroscopy and apply it to the double AugerMeitner (AM) emission process following xenon 4d photoionization. The photoelectron and AM electron(s) are measured in coincidence by using a magnetic-bottle time-of-flight spectrometer, enabling an unambiguous assignment of the complete cascade pathways involving two AM electron emissions. In the presence of a near-infrared (NIR) laser pulse, the intermediate Xe2+* state embedded in the Xe3+ continuum is probed through single NIR photon absorption and the lifetime of this intermediate Xe2+* state is directly obtained as (109 +/- 22) fs.