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Debris disks or belts are important signposts for the presence of colliding planetesimals and, therefore, for ongoing planet formation and evolution processes in young planetary systems. Imaging of debris material at small separations from the star is very challenging but provides valuable insights into the spatial distribution of so-called hot dust produced by solid bodies located in or near the habitable zone. We report the first detection of scattered light from the hot dust around the nearby (d = 28.33 pc) A star HD 172555. We want to constrain the geometric structure of the detected debris disk using polarimetric differential Imaging (PDI) with a spatial resolution of 25 mas and an inner working angle of about 0.1$$. We measured the polarized light of HD 172555, with SPHERE-ZIMPOL, in the very broad band (VBB; $lambda=735$ nm) filter for the projected separations between 0.08$$ (2.3 au) and 0.77$$ (22 au). We constrained the disk parameters by fitting models for scattering of an optically thin dust disk taking the limited spatial resolution and coronagraphic attenuation of our data into account. The geometric structure of the disk in polarized light shows roughly the same orientation and outer extent as obtained from thermal emission at 18 $mu$m. Our image indicates the presence of a strongly inclined ($isim 103.5^circ$), roughly axisymmetric dust belt with an outer radius in the range between 0.3$$ (8.5 au) and 0.4$$ (11.3 au). We derive a lower limit for the polarized flux contrast ratio for the disk of $(F_{rm pol})_{rm disk}/F_{rm ast}> (6.2 pm 0.6)cdot 10^{-5}$ in the VBB filter. This ratio is small, only 9 %, when compared to the fractional infrared flux excess ($approx 7.2cdot 10^{-4}$). The model simulations show that more polarized light could be produced by the dust located inside 2 au, which cannot be detected with the instrument configuration used.
Using the POLISH instrument, I am unable to reproduce the large-amplitude polarimetric observations of Berdyugina et al. (2008) to the >99.99% confidence level. I observe no significant polarimetric variability in the HD 189733 system, and the upper
The identification of a universal biosignature that could be sensed remotely is critical to the prospects for success in the search for life elsewhere in the universe. A candidate universal biosignature is homochirality, which is likely to be a gener
We studied the well known circumstellar disk around the Herbig Ae/Be star HD 97048 with high angular resolution to reveal undetected structures in the disk, which may be indicative of disk evolutionary processes such as planet formation. We used the
The debris disc around HD 172555 was recently imaged in near-infrared polarised scattered light by the Very Large Telescopes Spectro-Polarimetric High-contrast Exoplanet REsearch instrument. Here we present optical aperture polarisation measurements
We present the first scattered-light images of two debris disks around the F8 star HD 104860 and the F0V star HD 192758, respectively $sim45$ and $sim67$ pc away. We detected these systems in the F110W and F160W filters through our re-analysis of arc