Collision-induced decay of metastable baby Skyrmions - art. no. 105028

Many extensions of the standard model predict heavy metastable particles wh ich may be modeled as solitons (Skyrmions of the Higgs field), relating the ir particle number to a winding number. Previous work has shown that the el ectroweak interactions admit processes in which these solitons decay, viola ting the standard model baryon number. We motivate the hypothesis that bary on-number-violating decay is a generic outcome of collisions between these heavy particles. We do so by exploring a (2+1)-dimensional theory which als o possesses metastable Skyrmions. We use relaxation techniques to determine the size, shape, and energy of static solitons in their ground state. Thes e solitons could decay by quantum-mechanical tunneling. Classically, they a re metastable: only a finite excitation energy is required to induce their decay. We attempt to induce soliton decay in a classical simulation by coll iding pairs of solitons. We analyze the collision of solitons with varying inherent stabilities and varying incident velocities and orientations. Our results suggest that winding-number violating decay is a generic outcome of collisions. All that is required is sufficient (not necessarily very large ) incident velocity; no fine-tuning of initial conditions is required.