Simultaneous single-pulse observations of radio pulsars

II. Orthogonal polarization modes in PSR B1133+16

¹ Max-Planck Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
² Jodrell Bank Observatory, University of Manchester, Macclesfield, Chesire SK11 9DL, UK
³ School of Physics, University of Sydney, NSW 2006, Australia
⁴ Arecibo Observatory, HC3 Box 53995, Arecibo, Puerto Rico, PR 00612, USA
⁵ NCRA, TIFR, Pune University Campus, Ganeshkhind, Pune 411007, India

Corresponding author: A. Karastergiou, akara@mpifr-bonn.mpg.de

Received: 21 May 2002
Accepted: 27 May 2002

Abstract

In this letter, we present a study of orthogonal polarization modes in the radio emission of PSR B1133+16, conducted within the frame of simultaneous, multi-frequency, single-pulse observations. Simultaneously observing at two frequencies (1.41 GHz and 4.85 GHz) provides the means to study the bandwidth of polarization features such as the polarization position angle. We find two main results. First, that there is a high degree of correlation between the polarization modes at the two frequencies. Secondly, the modes occur more equally and the fractional linear polarization decreases towards higher frequencies. We discuss this frequency evolution and propose propagation effects in the pulsar magnetosphere as its origin.