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تسجيل مستخدم جديدBelt(s) of debris resolved around the Sco-Cen star HIP 67497
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In 2015, we initiated a survey of Scorpius-Centaurus A-F stars that are predicted to host warm-inner and cold-outer belts of debris similar to the case of the system HR~8799. The survey aims to resolve the disks and detect planets responsible for the disk morphology. In this paper, we study the F-type star HIP~67497 and present a first-order modelisation of the disk in order to derive its main properties. We used the near-infrared integral field spectrograph (IFS) and dual-band imager IRDIS of VLT/SPHERE to obtain angular-differential imaging observations of the circumstellar environnement of HIP~67497. We removed the stellar halo with PCA and TLOCI algorithms. We modeled the disk emission with the GRaTeR code. We resolve a ring-like structure that extends up to $sim$450 mas ($sim$50 au) from the star in the IRDIS and IFS data. It is best reproduced by models of a non-eccentric ring with an inclination of $80pm1^{circ}$, a position angle of $-93pm1^{circ}$, and a semi-major axis of $59pm3$ au. We also detect an additional, but fainter, arc-like structure with a larger extension (0.65 arcsec) South of the ring that we model as a second belt of debris at $sim$130 au. We detect 10 candidate companions at separations $geq$1. We estimate the mass of putative perturbers responsible for the disk morphology and compare it to our detection limits. Additional data are needed to find those perturbers, and to relate our images to large-scale structures seen with HST/STIS.
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