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IRDIS

The polarimetric imaging mode of VLT/SPHERE/IRDIS II : Characterization and correction of instrumental polarization effects

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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 such measurements, but uncalibrated instrumental polarization effects limit the attainable polarimetric accuracy. Aims. We aim to characterize and (...)

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The polarimetric imaging mode of VLT/SPHERE/IRDIS I : Description, data reduction and observing strategy

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Context. Polarimetric imaging is one of the most effective techniques for high-contrast imaging and characterization of protoplanetary disks, and has the potential to be instrumental in characterizing exoplanets. VLT/SPHERE contains the InfraRed Dual-band Imager and Spectrograph (IRDIS) with a dual-beam polarimetric imaging (DPI) mode, which offers the capability to obtain linear polarization (...)

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Exoplanet characterization with long slit spectroscopy

Context : Extrasolar planets observation and characterization by high contrast imaging instruments is set to be a very important subject in observational astronomy. Dedicated instruments are being developed to achieve this goal with very high efficiency. In particular, full spectroscopic characterization of low temperature planetary companions is an extremely important milestone. Aims : We (...)

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Photometric characterization of exoplanets using angular and spectral differential imaging

In recent years, there has been intensive research into the direct detection of exoplanets. Data obtained in the future with high-contrast imaging instruments, optimized for the direct detection of giant planets, may be strongly limited by speckle noise. Specific observing strategies and data analysis methods, such as angular and spectral differential imaging, are required to attenuate the (...)

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The infra-red dual imaging and spectrograph for SPHERE : design and performance

The SPHERE (Spectro-Polarimetric High-contrast Exoplanet Research) planet finder instrument for ESO’s VLT telescope, scheduled for first light in 2011, aims to detect giant extra-solar planets in the vicinity of bright stars by the aid of an extreme-AO turbulence compensation system and to characterize the objects found through spectroscopic and polarimetric observations. Dual imaging (...)

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High contrast polarimetry in the infrared with SPHERE on the VLT

The instrument SPHERE (Spectro-Polarimetric High-contrast Exoplanet REsearch), recently installed on the VLT-UT3, aims to detected and characterize giant extra-solar planets and the circumstellar environments in the very close vicinity of bright stars. The extreme brightness contrast and small angular separation between the planets or disks and their parent stars have so far proven very (...)

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SPHERE/IRDIS : final performance assessment of the dual-band imaging and long slit spectroscopy modes

The near-infrared imager and spectrograph IRDIS is one of the three science sub-systems of VLT/SPHERE dedicated to the detection and characterization of giant exoplanets at large orbital radii. It offers a wide range of observational modes including dual-band imaging (DBI) with very low differential aberrations, and long slit spectroscopy (LSS) coupled with a classical Lyot coronagraph at low (...)

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Infrared differential imager and spectrograph for SPHERE : performance assessment for on-sky operation

SPHERE (Spectro-Polarimetric High-contrast Exoplanet Research) is a second-generation instrument for the VLT, optimized for very high-contrast imaging around bright stars. Its primary goal is the detection and characterization of new giant planets around nearby stars, together with the observation of early planetary systems and disks. The Infrared Dual Imager and Spectrograph (IRDIS), one of (...)

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