Reduction of the angular divergence of a molecular beam by a coaxial beam of electrons

The angular divergences of molecular beams of several species are reduced substantially if they move coaxially with an electronic beam. The flux of molecules observed arriving at a detector set on the axis of the molecular beam is increased by factors up to 10³ for a beam of KCl and 10 ² for a beam of K. The increases become smaller as the intensity of the beams is increased. A model proposed to account for the results attributes the collimating action of the electronic beam to the decreased energy of states of the molecules and atoms in the field produced by the electronic beam.