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We have produced and characterised a slow, bright and intense atomic beam of metastable helium atoms, suitable for atomic physics experiments. The maximum continuous flux attained was 2×1010 atoms/s, while a typical longitudinal peak velocity of the beam was ∼26 m/s with a divergence in the range of 15 mrad to 30 mrad.

We have developed a novel, high flux source of metastable rare gas atoms (helium, neon and argon) that uses liquid helium cooling to reduce the initial atomic velocity. Fluxes exceeding 1014 atoms/ster/s with He and Ne were obtained. With average velocities of ∼600 m/s for He and ∼300 m/s for Ne and Ar, this source will enable simpler, more compact beam lines for loading magneto-optical traps.

The Aharonov-Casher (AC) phase is calculated in relativistic wave equations of spin one. The AC phase has previously been calculated from the Dirac-Pauli equation using a gauge-like technique \cite{MK1,MK2}. In the spin-one case, we use Kemmer theory (a Dirac-like particle theory) to calculate the phase in a similar manner. However the vector formalism, the Proca theory, is more widely known and used. In the presence of an electromagnetic field, the two theories are `equivalent' and may be transformed into one another. We adapt these transformations to show that the Kemmer theory results apply to the Proca theory. Then we calculate the Aharonov-Casher phase for spin-one particles directly in the Proca formalism.

We report loading large numbers (up to 3×109) of metastable triplet helium atoms into a magneto-optical trap using an atomic beam derived from a liquid He (LHe) cooled dc discharge source. Moreover, we compare the effect of liquid N2 cooling to LHe cooling the source and demonstrate that LHe cooling offers a significant increase in performance.