IXPE spectra of the Stokes Q and U parameters for the two (mutually exclusive) regions used for the polarimetric measurements of the reflected emission: the r =4.5′ circle (also excluding regions around G0.13-0.11) and the brightest reflection region. The dashed lines show the expected Q and U spectra for the model with the same PA and Stokes I and PD=100%. The data were uniformly binned only for visualization purposes.