Hole Photoproduction in Insulating Copper Oxide

To explain the experimental spectra for angle resolved photoemission we consider a modified t-J model. The modified model includes next nearest (t') and next next nearest (t'') hopping as well as Hubbard model corrections to the spectral weights. A Dyson equation which relates the single hole Green's functions for a given pseudospin and given spin is derived and is compared to experimental results.