Core emission in classical conal double pulsars

Abstract

A focus on single-pulse methods has identified what appears to be core emission in pulsars B0525+21, B0301+19 and B1133+16. Such core emission has been suspected in several ‘classical’ double conal pulsars; however, previous methods of analysis have restricted our ability to look further into this possibility. While average profiles of pulsars inform about the typical behaviours of these stars, single-pulse observations shed light on the atypical behaviours and weak features of a pulsar's emission. Emission in the ‘intrapulse region’ is not detectable in the average profiles but becomes clear in low-intensity and single-pulse observations. Through a process of suppressing the outer conal emission and averaging non-consecutive pulses that exhibit peaks in a central search region, reliable partial profiles of these putative core features have been obtained. In each case, the widths of the central features squared well with the expected polar cap geometry, further strengthening their identification with core emission components.