Kavli Affiliate: Herman L. Marshall
| First 5 Authors: Roberto Turolla, Roberto Taverna, Gian Luca Israel, Fabio Muleri, Silvia Zane
| Summary:
Recent observations with the Imaging X-ray Polarimetry Explorer (IXPE) of two
anomalous X-ray pulsars provided evidence that X-ray emission from magnetar
sources is strongly polarized. Here we report on the joint IXPE and XMM-Newton
observations of the soft {gamma}-repeater SGR 1806-20. The spectral and timing
properties of SGR 1806-20 derived from XMM-Newton data are in broad agreement
with previous measurements; however, we found the source at an all-time-low
persistent flux level. No significant polarization was measured apart from the
4-5 keV energy range, where a probable detection with PD=31.6pm 10.5% and
PA=-17.6pm 15 deg was obtained. The resulting polarization signal, together
with the upper limits we derive at lower and higher energies 2-4 and 5-8 keV,
respectively) is compatible with a picture in which thermal radiation from the
condensed star surface is reprocessed by resonant Compton scattering in the
magnetosphere, similar to what proposed for the bright magnetar 4U 0142+61.
| Search Query: ArXiv Query: search_query=au:”Herman L. Marshall”&id_list=&start=0&max_results=3