The photoionization cross sections for Ar ϩ through Ar 4ϩ , produced by the Auger decay of a 2 p hole in argon, have been measured between 242 eV and 253 eV by the use of synchrotron radiation. The high resolution of the monochromator has allowed a detailed study of the postcollision interactions that occur in this spectral region. The concept of photoelectron recapture by Ar 2ϩ to produce the Ar ϩ continuum is studied. The relative values of the quantum-mechanical calculations of the

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... ron recapture probability are shown to be in excellent agreement with the present data. The magnitude and shape of the Ar 2ϩ continuum has been explained on the basis that about 67% of the recaptured photoelectrons produce excited states of Ar ϩ which subsequently reemit the electrons by autoionization. ͓S1050-2947͑96͒02308-6͔