ADIABATIC STABILIZATION OF EXCITED-STATES OF H IN AN INTENSE LINEARLYPOLARIZED LASER FIELD

The lifetime of atomic hydrogen exposed to an intense ''high-frequency '' linearly polarized laser field has been calculated, in a Sturmian-F loquet approach, for the case where the atom is initially in an excite d state with m = 3, 4, 5, or 6, l = m, m + 1, or m + 2, and n less-tha n-or-equal-to 8, for several wavelengths between 455 and 1064 nm. In t his range of parameters, the intensity at which the lifetime of the at om reaches a minimum value is given in good approximation by a simple ''empirical' law. The lifetime is longer than that predicted by previo us approximate Floquet calculations, and its minimum occurs at a small er intensity. Results for higher-lying Rydberg states are also present ed.