Polarization Properties of Nine Southern Radio Pulsars

Abstract

We report on radio polarimetry observations for nine southern pulsars. Six of the nine in the sample are young, with characteristic ages under 100 kyr and high spin-down luminosities. All six show a significant degree of linear polarization. We also confirm a previously noticed trend in which the degree of linear polarization increases with spin-down luminosity. Where possible we have used the rotating-vector model of the pulsar emission geometry to fit the observed position angle data. Our fit for PSR J1513-5908 (B1509-58) in particular is useful for directly testing the magnetospheric model of Melatos (1997) in combination with further timing observations. For this pulsar we find that a magnetic inclination angle greater than or equal to 60 degrees is excluded at the 3-sigma level, and that the geometry suggested by the morphology of an apparent bipolar X-ray outflow is marginally inconsistent with the Melatos model. We also report on polarimetry of three older pulsars: PSR J0045-7319, PSR J1627-4845, and PSR J1316-6232 (whose discovery we also report). Of these, only PSR J0045-7319 shows significant polarization.