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The SPHERE view of the jet and the envelope of RY Tau

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Jets are rarely associated with pre-main-sequence intermediate-mass stars. Optical and near-IR observations of jet-driving sources are often hindered by the presence of a natal envelope. Jets around partly embedded sources are a useful diagnostic to constrain the geometry of the concealed protoplanetary disk. In fact, the jet-driving mechanisms are affected by both spatial anisotropies and (...)

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The gravitational mass of Proxima Centauri measured with SPHERE from a microlensing event

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Proxima Centauri, our closest stellar neighbour, is a low-mass M5 dwarf orbiting in a triple system. An Earth-mass planet with an 11 day period has been discovered around this star. The star’s mass has been estimated only indirectly using a mass-luminosity relation, meaning that large uncertainties affect our knowledge of its properties. To refine the mass estimate, an independent method has (...)

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Uncrowding R 136 from VLT/SPHERE extreme adaptive optics

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Jun. 2017 : This paper presents the sharpest near-IR images of the massive cluster R 136 to date, based on the extreme adaptive optics of the SPHERE focal instrument implemented on the ESO Very Large Telescope and operated in its IRDIS imaging mode.The crowded stellar population in the core of the R 136 starburst compact cluster remains still to be characterized in terms of individual (...)

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Upper limits for mass and radius of objects around Proxima Cen from SPHERE/VLT

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Mar. 2017 : The recent discovery of an earth-like planet around Proxima Centauri has drawn much attention to this star and its environment. We performed a series of observations of Proxima Centauri using Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE), the planet-finder instrument installed at the European Southern Observatory (ESO) Very Large Telescope (VLT) UT3, using its (...)

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SPHERE/ZIMPOL observations of the symbiotic system R Aquarii. I. Imaging of the stellar binary and the innermost jet clouds

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Jun. 2017 : R Aqr is a symbiotic binary system consisting of a mira variable, a hot companion with a spectacular jet outflow, and an extended emission line nebula. Because of its proximity to the Sun, this object has been studied in much detail with many types of high resolution imaging and interferometric techniques. We have used R Aqr as test target for the visual camera subsystem ZIMPOL, (...)

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The close circumstellar environment of Betelgeuse. III. SPHERE/ZIMPOL imaging polarimetry in the visible

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Jan. 2016 : The physical mechanism through which the outgoing material of massive red supergiants is accelerated above the escape velocity is unclear. Thanks to the transparency of its circumstellar envelope, the nearby red supergiant Betelgeuse gives the opportunity to probe the innermost layers of the envelope of a typical red supergiant down to the photosphere, i.e. where the acceleration (...)

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VLT/SPHERE deep insight of NGC 3603’s core : Segregation or confusion ?

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Apr. 2016 : We present new near-infrared photometric measurements of the core of the young massive cluster NGC 3603 obtained with extreme adaptive optics. The data were obtained with the SPHERE instrument mounted on ESO’s Very Large Telescope, and cover three fields in the core of this cluster. We applied a correction for the effect of extinction to our data obtained in the J and K broadband (...)

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Sub-0.1-arcsec optical imaging of the Z CMa jets with SPHERE/ZIMPOL

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Sep. 2016 : Crucial information on the mass accretion-ejection in young stars can be obtained from high spatial resolution images of jets in sources with recurrent accretion outbursts. Using the SPHERE/ZIMPOL instrument, we observed the young binary Z CMa that is composed of a Herbig Be star and a FUor object, both driving a (...)

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