Bose-Einstein condensation of atomic hydrogen

The recent creation of a Bose-Einstein condensate of atomic hydrogen has added a new system to this exciting field, The differences between hydrogen and the alkali metal atoms require other techniques for the initial trapping and cooling of the atoms and the subsequent detection of the condensate. The use of a cryogenic loading technique results in a larger number of trapped atoms. Spectroscopic detection is well suited to measuring the temperature and density of the sample in situ. The transition was observed at a temperature of 50 mu K and a density of 2 x 10(14) cm(-3). The number of condensed atoms is about 10(9) at a condensate fraction of a few percent. A peak condensate density of 4.8 x 10(15) cm(-3) has been observed