Photo Double-Ionization of Deuterium Chloride Studied by Threshold Photo-
electrons Coincidence Spectroscopy

G.C. King(1), A.J. Yencha(2), M.C.A. Lopes(1,3), J.D. Bozek(4), N. Berrah(5)

(1) Manchester University
(2) University at Albany
(3) Univeridade Federal de Juiz de Fora
(4) Lawrence Berkeley National Laboratory
(5) Western Michigan University

Photo double-ionization (PDI) of DCl has been investigated in the 35-38 eV
energy range using synchrotron radiation on beamline 10.0.1.2 of the Advanced
Light Source (ALS) by the threshold photoelectrons coincidence (TPEsCO)
method.  The TPEsCO spectrum of DCl, encompassing the formation of the ground
(X 3sigma-) and first-excited (a 1delta) states of DCl++, was recorded at 
good resolution (about 13 meV) using a pair of penetrating-field electron
spectrometers.  Resonance autoionization of satellite-ion Rydberg states
appear to play a major role in the formation of these doubly-charged electronic
ion states.