Photoelectron angular distribution studies of the outer valence states of N2

We present angle resolved photoelectron data for the ionization of all N-2 outer valence shells namely the 3 sigma(g), 1 pi(u) and 2 sigma(u) states in the photon energy region from 19 to 50 eV with a photon energy step width down to 20 meV. Signatures due to the autoionization of doubly excited Rydberg states and the corresponding vibrational progression are observed in the dipole electron angular distribution parameter beta. They are compared with recent calculations. We also find evidence for theoretically predicted sharp resonance effects due to channel coupling in the electron angular distribution of 1 pi(-1)(u). Shape resonance and channel coupling effects are discussed for all outer valence orbitals with respect to recent theoretical findings.