The anomalous X-ray pulsar XTE J1810-197 was the first magnetar found
to emit pulsed radio emission. After spending almost a decade in a
quiescent, radio-quiet state, the magnetar was reported to have
undergone a radio outburst in 2018 December. We observed radio
pulsations from XTE J1810-197 during this early phase of its radio
revival using the Ultra-Wideband Low receiver system of the Parkes
radio telescope, obtaining wideband (704 MHz to 4032 MHz) polarization
pulse profiles, single pulses and flux density measurements. The
picture here shows the average polarization pulse spectra for XTE
J1810-197 taken on 2018 December 11. From left to right, we show total
intensity (Stokes I), linear polarization, and circular polariation
(Stokes V), normalized by their peak values. The position angle of the
linear polarization (over each 128 MHz subband) is shown as white
solid lines. The length of lines represents the fraction of linear
polarization. The observed wideband polarization properties are
significantly different compared to those taken after the 2003
outburst, and therefore provide new information about the origin of
radio emission.
More details are given
in the preprint of the paper, which will be published
in Astrophysical Journal Letters.
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