METERWAVELENGTH SINGLE-PULSE POLARIMETRIC EMISSION SURVEY

Abstract

We have conducted the Meterwavelength Single-pulse Polarimetric Emission Survey to study the radio emission properties of normal pulsars. A total of 123 pulsars with periods between 0.1 and 8.5 s were observed in the survey at two different frequencies: 105 profiles at 333 MHz, 118 profiles at 618 MHz, and 100 pulsars at both. In this work we concentrate primarily on the time-averaged properties of the pulsar emission. The measured widths of the pulsar profiles in our sample usually exhibit the radius-to-frequency mapping. We validate the existence of lower bounds for the distribution of profile widths with pulsar period ( P ), which is seen for multiple definitions of the width, namely, a lower boundary line (LBL) at 2.°7 P −0.5 with width measured at 50% level of profile peak, an LBL at 5.°7 P −0.5 for 10% level of peak, and an LBL at 6.°3 P −0.5 for width defined as 5 σ above the baseline level. In addition, we have measured the degree of linear polarization in the average profile of pulsars and confirmed their dependence on pulsar spin-down energy loss ( E ˙ ). The single-pulse polarization data show interesting trends, with the polarization position angle (PPA) distribution exhibiting the simple rotating vector model for high- E ˙ pulsars, while the PPA becomes more complex for medium- and low- E ˙ pulsars. The single-pulse total intensity data are useful for studying a number of emission properties from pulsars like subpulse drifting, nulling, and mode changing, which are being explored in separate works.