EN
We study the dynamics of bright solitons in a Bose-Einstein condensate confined in a highly asymmetric trap. While working within the framework of a variational approach we carry out the stability analysis of the Bose-Einstein condensate solitons against collapse. When the number of atoms in the soliton exceeds a critical number N_c, it undergoes the so-called primary collapse. We find an analytical expression for N_c in terms of appropriate experimental quantities that are used to produce and confine the condensate. We further demonstrate that, in the geometry of the problem considered, the width of the soliton varies inversely as the number of constituent atoms.