Participant double autoionization

PA = participant autoionization SA = spectator autoionization PDA = participant double autoionization, SDA = spectator double autoionization CA = cascade autoionization AD = Auger decay ASU = Augur decay with shake-up DAD = double Auger decay, ICD = interchannel decay. 

Several decay channels are possible. The most important are listed in Table II and are labeled PA (participant autoionization), SA (spectator autoionization), PDA (participant double autoionization), SDA (spectator double autoionization), and CA (cascade autoionization). 

Relaxation involving emission of more than one electron also occurs, e.g., participant double autoionization (PDA) and spjctator double autoionization (SDA). These channels leave the molecule with a +2 charge and in 2-hole and 3-hole 1-electron states, respectively. Sino relaxation of the core hole may leave the molecule with a deep valence hole or with an electron in a high energy orbital, additional autoionization, called delayed, subsequent or cascade autoionization (CA) can occur. An exiimple is given in Table II. 

---