Left column: total intensity images derived from our polarimetric observations with SPHERE in the J and H band. The circumstellar disk is not visible in these images since flux is completely dominated by the bright stellar PSF. The visible cavity in the image center is caused by the SPHERE/IRDIS coronagraph. The stellar PSF is strongly elongated in the southeast to northwest direction in the H-band observations. Additionally the star is not well centered behind the coronagraph, as is visible in the illumination pattern behind the (slightly transparent) coronagraph. Right column: Qφ images from Fig. 1 divided by the total intensity images in the left column. This is not equivalent with polarization degree, since the intensity images are dominated by the stellar PSF rather than disk signal. The visible bright lobes are aligned with the semiminor axis of the stellar PSF, i.e., they are caused by a drop off in stellar flux and not by the polarized phase function of the disk scattered light. It is visible that the asymmetric scattered light signal in the H band is less apparent in this image, indicating that it originates from the asymmetric flux in the stellar PSF which was not well centered behind the coronagraph, rather than from an actual astrophysical asymmetry in scattered light from the disk.
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