Soft oscillons

A bstract We present a novel type of soliton dubbed soft oscillons. In contrast with conventional oscillons the soft counterparts come in a continuum of unboundedly large sizes. They are peculiar also in that the oscillation frequency is set by their size and in their high harmonic content, that leads to a peculiar core structure and pulsating emission of radiation. Soft oscillons appear in a broad class of scalar field theories with plateau potentials and owe their existence to a simple confinement mechanism: a large field perturbation automatically acts as a cavity that traps massless modes. We study the classical evaporation rate, lifetime and stability under anisotropic deformations. Soft oscillons are longer lived in gapless models, where lifetimes can reach 100 times the initial radius or more.