A time dependent theory for radiative recombination induced by strong pulses is presented. Analytic solutions in the adiabatic limit are derived and found to be in excellent agreement with exact numerical solutions. Both the pump-before-dump ''intuitive'' and dump-before-pump ''counter-intuitive'' schemes are considered. Resonantly enhanced two-photon recombination of ultracold atoms is shown to be an efficient mechanism for the production of ultracold molecules. We have performed detailed calculations on the radiative recombination of cold Na atoms by short laser pulses. Our calculations show that, per pulse, it is possible for up to 97% of all head-on Na-Na colliding pairs to end up as vϭ0, Jϭ0 translationally cold Na 2 molecules. We show that these findings, translated to thermally cooled ensemble conditions, mean that the fraction of Na atoms at Kelvin which can be recombined by a pulse of 20 ns duration and 10 8 W/cm 2 peak intensity, to form Jϭ0 molecules is 6ϫ10 Ϫ6 per pulse. With the above parameters, a laser operating at 100 Hz can convert half of an ensemble of cold atoms to cold molecules in ϳ25 min. The efficiency of the process can be increased by going to longer pulses of lower intensity, by going to lower temperatures or by increasing the density of the ensemble. In particular, the ''counter-intuitive'' scheme which allows for use of longer pulses of lower intensities, with no spontaneous emission losses, considerably increases the yield.

Coherent control over branching in the photodissociation of collinear CH2BrI to yield either CH2Br+I or CH2I+Br is examined computationally. Quantum photodissociation calculations, using two excited potentials surfaces, are carried out using a new method incorporating negative imaginary absorbing potentials within the artificial channel method. Extensive control over the I/Br branching ratio is shown to result as experimentally controllable laser amplitudes and phases are varied. Such control is observed for excitation from either initial superpositions of chaotic or regular CH2BrI bound states.

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