Near threshold photoionization of excited alkali atoms Ak(np) (Ak = Na, K, Rb, Cs; n = 3-6) I. D. Petrov, V. L. Sukhorukov, E. Leber and H. Hotop Eur. Phys. J. D, 10 1 (2000) 53-65 Published online: 15 April 2000 DOI: 10.1007/s100530050526