MASS RESOLVED PHOTOIONIZATION AND PHOTODISSOCIATION OF CO FOLLOWING C(1S) EXCITATION

Photoionization and photodissociation of C(1s) core excited carbon mon oxide has been studied in the range 285-320 eV using mass spectroscopy at the undulator beam line 51 at the Swedish synchrotron facility MAX in Lund. Spectra of C+, O+, CO+, C2+, O2+ and CO2+ were recorded at a photon resolution comparable to high resolution photoabsorption measu rements. The results essentially agree with earlier investigations of the C(1s)-->pi excitation except for an earlier unobserved strong enh ancement of the upsilon'=4 resonance. However, surprising results are obtained for the relative intensities of C(1s) excitations to singly a nd doubly excited Rydberg levels in the different fragmentation channe ls.