Broad-band laser optical pumping of Rb for the creation of nuclear polarisation in He-3

A large volume (30 cm(3)) of dense (up to 10(15) cm(-3)) Rb vapour was pump ed optically by a high-power laser diode array. The conditions for the prop agation of high-power broad-band optical pump radiation through an opticall y dense medium were examined. A spectroscopic method was developed for dete rmination of the polarisation of Rb. The dependence of the polarisation of Rb on its vapour pressure was investigated at buffer gas pressures of 1, 8, and 13 bar. Under optimal conditions a 15-W diode laser made it possible t o polarise at least 10(18) of He-3 atoms per second during collisions betwe en Rb and He-3 atoms, sufficient for the creation of an efficient neutron p olariser.