  It has been made an extention of the conventional theory based on the
assumption of the well isolated Zhang-Rice singlet to be a first
electron-removal state in dielectric copper oxide. One assumes the photohole
has been localised on either small (pseudo)Jahn-Teller polaron or large
non-adiabatic polaron enclosed one or four to five $CuO_4$ centers,
respectively, with active one-center valent $(^{1}A_{1g}-{}^{1,3}E_{u})$
manifold. In the framework of the cluster model we have performed a model
microscopic calculation of the ${\bf k}$-dependence of the matrix element
effects and photon polarization effects for the angle-resolved photoemission in
dielectric cuprate like $Sr_{2}CuO_{2}Cl_{2}$. We show that effects like the
''remnant Fermi surface'' detected in ARPES experiment for
$Ca_{2}CuO_{2}Cl_{2}$ may be, in fact, a reflection of the matrix element
effects, not a reflection of the original band-structure Fermi surface, or the
strong antiferromagnetic correlations. The measured dispersion-like features in
the low-energy part of the ARPES spectra may be a manifestation of the complex
momentum-dependent spectral line-shape of the large PJT polaron response, not
the dispersion of the well-isolated Zhang-Rice singlet in antiferromagnetic
matrix.
