Jm. Doyle et al., EVAPORATIVE COOLING OF ATOMIC-HYDROGEN - THEORY OF COOLING AND PROGRESS TOWARDS THE BOSE-EINSTEIN TRANSITION, Physica. B, Condensed matter, 194, 1994, pp. 13-14
We present a model for and the results of experiments on evaporative c
ooling of magnetically trapped atomic hydrogen. Forced evaporative coo
ling and compression were performed simultaneously to produce a sample
with a density of 8 x 10(13) cm-3 at a temperature of 100 muK, a fact
or of 3.5 above the critical temperature of the Bose-Einstein condensa
tion phase transition at this density and well below the 1.3 mK recoil
limit for laser cooling. A quantitative model of evaporative cooling
has been developed and its predictions are in good agreement with the
data.