The topology and polarization of sub-beams associated with the 'drifting' sub-pulse emission of pulsar B0943+10-I. Analysis of Arecibo 430- and 111-MHz observations

The ‘drifting’ sub-pulses exhibited by some radio pulsars have fascinated both observers and theorists for 30 years, and have been widely regarded as one of the most critical and potentially insightful aspects of their emission. Moreover, Ruderman a 1972 430-MHz ‘B’-mode sequence; and a 1990 111-MHz ‘B’-mode sequence. The ‘B’-mode sequences are consistent in revealing that the emission pattern consists of 20 sub-beams, which rotate around the magnetic axis in about 37 periods or 41 s. Even in the ‘Q’-mode sequence, we find evidence of a compatible circulation time. The similarity of the sub-beam patterns at different radio frequencies strongly suggests that the radiation is produced within a set of columns, which extend from close to the stellar surface up through the emission region and reflect some manner of ‘seeding’ phenomenon at their base. The sub-beam emission is then tied neither to the stellar surface nor to the field. While the origin of the ‘memory’ responsible for the stability of the pattern over several circulation times is unknown, the hollow conical form of the average pattern is almost certainly the origin of the conal beam forms observed in most pulsars.