We present a simple model of ultracold cesium dimer formation in which the photoassociation into rovibrational levels of the double-minimum
Cs2 $3{}^{1}{\ensuremath{\Sigma}}_{u}^{+}$ state above its internal barrier enables spontaneous or stimulated emission into the lowest rovibrational levels of the
Cs2 $1(X){}^{1}{\ensuremath{\Sigma}}_{g}^{+}$ ground electronic state. The transition dipole moment should be sufficiently large for observation of such spectral transitions. The use of the
Cs2 $3{}^{1}{\ensuremath{\Sigma}}_{u}^{+}$ double-minimum potential could be extended to molecular Bose-Einstein condensates in which an optical trap can be employed for trapping of both atomic and molecular species.
Several different experiments involving the making of cold and ultracold molecules are performed and proposed. Ultracold cesium molecules are produced in a magneto-optical trap (MOT) by photoassociation near the 6P j, 7Pj, 9S 1/2, 6D3/2, 7D3/2 and doubly excited asymptotes. Perturbation effects related to resonant channel coupling were observed in photoassociation spectra below the 6 P1/2 asymptote. Such effects are used to illustrate a ground state ultracold molecule formation mechanism, which can also be formed in one step photoassociation to the double minimum 31S+m state. In addition, a new technique of making cold molecules of cesium hydride is proposed, using a cold hydrogen beam source and a cesium MOT. Due to reaction energetics, the formed CsH molecules should be in their lowest rovibrational states. ^