TECHNIQUES: POLARIMETRIC

Biosignatures of the Earth. I. Airborne spectropolarimetric detection of photosynthetic life

Context. Homochirality is a generic and unique property of life on Earth and is considered a universal and agnostic biosignature. Homochirality induces fractional circular polarization in the incident light that it reflects. Because this circularly …

A survey of the linear polarization of directly imaged exoplanets and brown dwarf companions with SPHERE-IRDIS. First polarimetric detections revealing disks around DH Tau B and GSC 6214-210 B

Context. Young giant planets and brown dwarf companions emit near- infrared radiation that can be linearly polarized up to several percent. This polarization can reveal the presence of an (unresolved) circumsubstellar accretion disk, rotation-induced …

RefPlanets: Search for reflected light from extrasolar planets with SPHERE/ZIMPOL

Aims: RefPlanets is a guaranteed time observation programme that uses the Zurich IMaging POLarimeter (ZIMPOL) of Spectro-Polarimetric High-contrast Exoplanet REsearch instrument at the Very Large Telescope to perform a blind search for exoplanets in …

Polarimetric imaging mode of VLT/SPHERE/IRDIS. I. Description, data reduction, and observing strategy

Context. Polarimetric imaging is one of the most effective techniques for high-contrast imaging and for the characterization of protoplanetary disks, and it has the potential of becoming instrumental in the characterization of exoplanets. The …

Polarimetric imaging mode of VLT/SPHERE/IRDIS. II. Characterization and correction of instrumental polarization effects

Context. Circumstellar disks and self-luminous giant exoplanets or companion brown dwarfs can be characterized through direct- imaging polarimetry at near-infrared wavelengths. SPHERE/IRDIS at the Very Large Telescope has the capabilities to perform …

Polarimetric imaging of circumstellar disks. I. Artifacts due to limited angular resolution

Context. Polarimetric images of circumstellar environments, even when corrected with adaptive optics, have a limited angular resolution. Finite resolution greatly affects polarimetric images because of the canceling of adjacent polarization signals …

First direct detection of a polarized companion outside a resolved circumbinary disk around CS Chamaeleonis

Aims: To understand planet formation it is necessary to study the birth environment of planetary systems. Resolved imaging of young planet forming disks allows us to study this environment in great detail and find signs of planet-disk interaction and …

BP Piscium: its flaring disc imaged with SPHERE/ZIMPOL$^★$

Whether BP Piscium (BP Psc) is either a pre-main sequence T Tauri star at d ensuremath≈ 80 pc, or a post-main sequence G giant at d ensuremath≈ 300 pc is still not clear. As a first-ascent giant, it is the first to be observed with a molecular and …

Direct detection of scattered light gaps in the transitional disk around HD 97048 with VLT/SPHERE

Aims: 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. …

Surprising detection of an equatorial dust lane on the AGB star IRC+10216

Aims: Understanding the formation of planetary nebulae remains elusive because in the preceding asymptotic giant branch (AGB) phase these stars are heavily enshrouded in an optically thick dusty envelope. Methods: To further understand the morphology …