Self-energy corrections in photoemission of Na

We have calculated the photoemission spectra of Na, where self-energy corrections and surface effects are fully incorporated. The self-energy is calculated with the Rayleigh-Schr\"odinger perturbation method. The energy shifts in both the initial states and the final states are specifically demonstrated by comparing the calculation with the measured results of Plummer and co-workers. It is found that both the imaginary part and the real part of the self-energy contribute to the observed large bandwidth reduction in Na. We believe these effects to be important, in general, in analyzing photoemission spectra.