Number 248 (Story #1), November 10, 1995 by Phillip F. Schewe and Ben Stein
A BOSE EINSTEIN CONDENSATE (BEC) OF SODIUM ATOMS has been observed by Wolfgang Ketterle and his colleagues at MIT (617-253-6815). Their condensate consisted of about a half million sodium atoms, compared to the 2000 rubidium atoms in the case of the BEC observed in the previous NIST/Colorado demonstration (Update 233) and the 100,000 lithium atoms at Rice (Update 237). The greater number of atoms (with a density of 10**14 cm**-3) and the much faster condensation rate (some 10,000 times faster at MIT than for NIST/Colorado) will aid the actual study of (and not merely the demonstration) of this new state of matter, whose properties are still unknown. Recall that the BEC state is not a condensation of atoms in the ordinary sense of clumping together, but rather a single coherent atomic entity. (K.B. Davis et al., upcoming article in the 27 November 1995 Physical Review Letters; journalists can obtain a copy by contacting physnews@aip.org)
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