Figure 1

(a) Histogram of the sum of the energies of the 2 photoelectrons associated with core DI, when detected in coincidence with the two released Auger electrons of 200–270 and 270–320 eV. (b) Our predictions for the 1-site DCH spectrum (bars convoluted with a 3 eV FWHM Gaussian to mimic experimental resolution). A $\times 100$ magnifying factor is used to visualize the position of the lowest energy satellite state (dotted line). (c) Same as in (a) but coincidence is with only one Auger electron of 230–250 eV. Electrons of less than 10 eV in (a) and (c) and of more than 60 eV in (c) have been discarded to reduce background. Vertical bars at the bottom correspond to our theoretical calculations for the position of the DCH main lines. A photon energy of $h\nu =770.5\mathrm{eV}$ was used.Reuse & Permissions

Figure 2

Auger spectra associated with the decay of: (a) a 2-site DCH, (b) a 1-site DCH, (c) a 1-site DCH satellite and (d) a single $K$-shell core hole, (d) was obtained from coincidences with a $1s$ photoelectron. (a) to (c) was obtained from coincidences with a pair of photoelectrons whose energy sum defines the corresponding DCH states. Four-electron coincidence events were used for (b) and (c) and 3-electron ones for (a). Background was estimated from adjacent zones of energy sums and subtracted. In (b) and (c) the solid line displays the first emitted hypersatellite Auger electron, while the dotted line corresponds to the second emitted, satellite Auger electron; the top scale applies only for the first hypersatellite Auger electron (solid line).Reuse & Permissions

Figure 3

Binding energy of the ${\mathrm{C}}_2\mathrm{H}_2{}^{4+}$ final states populated by the complete Auger decay of 1-site (a) and 1-site satellite (b) DCHs. They are deduced from 4-electron coincidence events and the histogram of $h\nu$ (sum of 4 electron energies). Events with electrons of less than 10 eV were discarded to reduce background.Reuse & Permissions