2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/93548We demonstrate analytically that a Bose-Einstein condensate confined in a harmonic trap with zero-range attractive interparticle interactions is unstable if there is more than 1 boson. Replacing the zero-range interaction by a short-range attractive interaction lifts the instability, and leads to a pronounced clustering, by which the particles leak out of the condensate.2 pages, Revtex, no figuresQuantum Physicstext