Production of Na/sub 2/ /sup +/ by crossed-beam collisions in the presence of intense, nonresonant radiation

We report the results of a battery of experiments to determine the origin of ${\mathrm{Na}}_{2}^{+}$ produced by crossed sodium beams in the presence of intense optical radiation. The principal mechanism appears to be atomic collision combined with photon absorption. The characteristics of long-range optical collisions are compared with those expected from collisional resonances.