Structure of pulsar beams: conal versus patchy

Structure of mean pulsar radiation patterns is discussed within the nested-cones and patchy beam models. Observational predictions of both these models are analyzed and compared with available data on pulsar waveforms. It is argued that observational properties of pulsar waveforms are highly consistent with the nested-cone model and, in general, inconsistent with the patchy beam model.Comment: Astronomy & Astrophysics, in pres