| Description: | Until very recently, radio emission from neutron stars was only detected from radio pulsars. Magnetars are considered to be slowly rotating neutron stars visible as bursting X-ray and gamma-ray sources, characterized by long spin-periods of 5-12 seconds and a rapid spin-down. The observed X-ray and gamma-ray luminosities are usually orders of magnitude larger than would be expected if they were powered by the spin-down energy as is the emission from "normal" radio pulsars. These are clearly different from normal radio pulsars, however Camilo et al. (2006a) reported observations of the radio emission which, remarkably, revealed a strong detection of pulsations with the known 5.54~s period.
To better study this radio emission we instigated a series of simultaneous observations with the WSRT, Effelsberg and the Lovell telescope to study both the individual pulses and the polarisation at multiple frequencies. Here we show just one of the amazing characteristics of the radio emission from this source. Plots of the average pulse shapes in full polarization observed over several weeks at 4.9 GHz (WSRT:left) and 8.4 GHz (Effelsberg:right) are shown. One can see that unlike normal radio pulsars there is a huge variation in the pulse shape, however, in general the polarisation position angle stays remarkably steady. This work has recently been accepted for publication by MNRAS http://arxiv.org/abs/astro-ph/0702365 |
