EFFECT OF A FINITE NUMBER OF PARTICLES IN THE BOSE-EINSTEIN CONDENSATION OF A TRAPPED GAS

We consider a finite number of noninteracting bosons trapped in an iso tropic three-dimensional harmonic oscillator. Using the grand canonica l ensemble, we calculate the heat capacity of the system as a function of temperature, for several values of the number of particles. We fin d that a new definition of critical temperature is necessary for a fin ite number of trapped particles, and present a definition that is expe rimentally convenient and in good agreement with a recent definition g iven by W. Ketterle and N. J. van Druten. .