Bound states in monopoles: sources for UHECR?

Bound states in monopoles are studied through a simplified, Witten-like mod el. As the overall structure is determined in full detail, it is shown in p articular that only those states having a vanishing angular momentum are al lowed; for those, the energy spectrum is derived numerically and an approxi mation is set up that allows an easy description in terms of wavefunctions, useful for further applications, The monopoles are then proposed as candid ates of ultra high energy cosmic rays, a hypothesis that should soon be tes table through the Pierre Auger Observatory. (C) 2000 Elsevier Science B.V. All rights reserved. PACS: 98.80.Cq; 11.27. + d.