Open AccessPolarization profiles of southern pulsars at 3.1 GHz
Author(s) -
Karastergiou A.,
Johnston S.,
Manchester R. N.
Publication year - 2005
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.08909.x
Subject(s) - physics , pulsar , linear polarization , superposition principle , polarization (electrochemistry) , astrophysics , stokes parameters , circular polarization , spectral density , computational physics , optics , scattering , laser , chemistry , quantum mechanics , microstrip , statistics , mathematics
ABSTRACT We present polarization profiles for 48 southern pulsars observed with the new 10‐cm receiver at the Parkes telescope. We have exploited the low system temperature and high bandwidth of the receiver to obtain profiles which have good signal‐to‐noise for most of our sample at this relatively high frequency. Although, as expected, a number of profiles are less linearly polarized at 3.1 GHz than at lower frequencies, we identify some pulsars and particular components of profiles in other pulsars which have increased linear polarization at this frequency. We discuss the dependence of linear polarization with frequency in the context of a model in which emission consists of the superposition of two, orthogonally polarized modes. We show that a simple model, in which the orthogonal modes have different spectral indices, can explain many of the observed properties of the frequency evolution of both the linear polarization and the total power, such as the high degree of linear polarization seen at all frequencies in some high spin‐down, young pulsars. Nearly all the position angle profiles show deviations from the rotating vector model; this appears to be a general feature of high‐frequency polarization observations.