Polarisation results from IXPE. Left: averaged PD and PA in the 2–8 keV band, as obtained from XSPEC with Model (1) for observation 8, including the contours of the 68.3% (blue), 95.5% (red), and 99.7% (green) confidence levels. The PA of 0° corresponds to the north direction, with positive values increasing eastwards. Right: PD and PA as a function of energy, as obtained from XSPEC with Model (1) for the same observation, 8 (blue diamonds). For comparison, we also show the energy dependence of polarisation for observations 3 (black circles) and 4 (grey squares) from Ingram et al. (2024), obtained in a similar way. The uncertainties are given at the 68.3% confidence level for one model parameter.