Compact Q-balls and Q-shells in a multi-component CPN model

Coupled multi-component CPN models with V-shaped potentials are analyzed. It is shown that the model has solutions being combinations of compact Q-balls and Q-shells. The compact nature of solutions permits the existence of novel harbor-type solutions having the form of Q-balls sheltered by Q-shells. The relation between the energy E and Noether charge Q is discussed both analytically and numerically. The energy of the solutions behaves as E similar to vertical bar Q vertical bar(alpha), alpha < 1, i.e., as for the standard Q-ball. Furthermore, the ratio E/Q for various configurations in the multi-component model suggests that the solutions are at least classically stable.