SOUND-PROPAGATION IN A CYLINDRICAL BOSE-CONDENSED GAS

We study the normal modes of a cylindrical Bose condensate at T = 0 us ing the linearized time-dependent Gross-Pitaevskii equation in the Tho mas-Fermi limit. These modes are relevant to the recent observation of pulse propagation in long, cigar-shaped traps. We find that pulses ge nerated in a cylindrical condensate propagate with little spread at a speed c = root g (n) over bar/m, where (n) over bar is the average den sity of the condensate over its cross-sectional area. [S1050-2947(98)0 6301-X].