Double autoionization of He-(2s22p 2P)

The double autoionization rate for the He-(2s(2)2p P-2) hollow atom state is calculated using a nonperturbative time-dependent close-coupling method. The nine-dimensional wave function for the three electron atom is expanded in coupled spherical harmonics. The time-dependent Schrodinger equation is then reduced to a set of close-coupled partial differential equations for the three-dimensional radial expansion functions. Relaxation in imaginary time subject to orthogonality constraints yields a 2s(2)2p P-2 hollow atom state with real energy, while propagation in real time yields total and double Auger rates. The total Auger rate is in reasonable agreement with previous saddle-point complex-rotation calculations. The double Auger rate is found to be 10% of the total Auger rate, in keeping with the relatively large double to total ratio found in recent experiments for He-(2s2p(2) P-4).