Markus Feldt

Discovery of the Coldest Imaged Companion of a Sun-Like Star (2009)

Thalmann, Christian, Carson, Joseph, Janson, Markus, Goto, Miwa, McElwain, Michael, Egner, Sebastian, ...

We present the discovery of a brown dwarf or possible planet at a projected separation of 1.9" = 29 AU around the star GJ 758, placing it between the separations at which substellar companions are...

Frame Combination Techniques for Ultra High-Contrast Imaging (2008)

Carson, Joseph C., Feldt, Markus, Desidera, Silvano, Langlois, Maud, Joos, Franco, Mouillet, David, ...

We summarize here an experimental frame combination pipeline we developed for ultra high-contrast imaging with systems like the upcoming VLT SPHERE instrument. The pipeline combines strategies from...

The SPHERE exoplanet imager: a new management paradigm? (2008)

Wildi, Francois, Beuzit, Jean-Luc, Feldt, Markus, Mouillet, David, Dohlen, Kjetil, Puget, Pascal

The SPHERE is an exo-solar planet imager, which goal is to detect giant exo-solar planets in the vicinity of bright stars and to characterize them through spectroscopic and polarimetric observations....

SPHERE ZIMPOL: overview and performance simulation (2008)

Thalmann, Christian, Schmid, Hans M., Boccaletti, Anthony, Mouillet, David, Dohlen, Kjetil, Roelfsema, Ronald, ...

The ESO planet finder instrument SPHERE will search for the polarimetric signature of the reflected light from extrasolar planets, using a VLT telescope, an extreme AO system (SAXO), a stellar...

A cryogenic dithering stage for moving SPHERE-IRDIS' detector (2008)

Rohloff, Ralf-Rainer, Blümchen, Thomas, Feldt, Markus, Naranjo, Vianak, Ramos, Jose, Müller, Klaus-Dieter, ...

This paper describes the development of the detector motion stage for the instrument SPHERE (Spectro-Polarimetric High-contrast Exoplanet REsearch). The detector movement is necessary because the...

SPHERE data reduction and handling system: overview, project status, and development (2008)

Pavlov, Alexey, Möller-Nilsson, Ole, Feldt, Markus, Henning, Thomas, Beuzit, Jean-Luc, Mouillet, David

The SPHERE project is a ESO second generation instrument which aims to detect giant extra-solar planets in the vicinity of bright stars and to characterise the objects found through spectroscopic and...

SPHERE baseline software for reducing calibration data (2008)

Feldt, Markus, Möller-Nilsson, Ole, Pavlov, Alexey I., Beuzit, Jean-Luc, Mouillet, David, Gratton, Raffaele, ...

The Spectro-Polarimetric High-contrast Exoplanet Research (SPHERE) instrument for the VLT is designed for discovering and studying new extra-solar giant planets orbiting nearby stars by direct...

Frame combination techniques for ultra-high-contrast imaging (2008)

Carson, Joseph C., Feldt, Markus, Desidera, Silvano, Langlois, Maud, Joos, Franco, Mouillet, David, ...

We summarize here an experimental frame combination pipeline we developed for ultra high-contrast imaging with systems like the upcoming VLT SPHERE instrument. The pipeline combines strategies from...

SPHERE: a planet finder instrument for the VLT (2008)

Beuzit, Jean-Luc, Feldt, Markus, Dohlen, Kjetil, Mouillet, David, Puget, Pascal, Wildi, Francois, ...

Direct detection and spectral characterization of extra-solar planets is one of the most exciting but also one of the most challenging areas in modern astronomy. The challenge consists in the very...

The formation and early evolution of massive stars (2006)

Henning, Th., Feldt, Markus, Linz, Hendrik, Antolin, Elena Puga, Stecklum, Bringfried

Not Available We present data obtained with the Infrared Array Camera (IRAC) aboard the Spitzer Space Telescope (Spitzer) for a sample of 74 young (t

The search for the sub-solar initial mass function in the Local Group (2006)

Gouliermis, Dimitrios, Berton, Alessandro, Brandner, Wolfgang, Henning, Thomas, Feldt, Markus

The stellar Initial Mass Function (IMF) is a quantity which accounts for the distribution of the masses of stars, when they are formed. All the information available on the IMF in the low-mass regime...

SPHERE: A planet finder instrument for the VLT (2006)

Dohlen, Kjetil, Beuzit, Jean-Luc, Feldt, Markus, Mouillet, David, Puget, Pascal, Antichi, Jacopo, ...

The Planet Finder instrument for ESO's VLT telescope, scheduled for first light in 2010, aims to detect giant extra-solar planets in the vicinity of bright stars and to characterise the objects found...

Simulating diffractions and chromatic effects in the microlens array in searching for extrasolar planets with SPHERE IFS (2006)

Berton, Alessandro, Gratton, Raffaele, Antichi, Jacopo, Dohlen, Kjetil, Claudi, Riccardo, Feldt, Markus, ...

Observations of extrasolar planets using Integral Field Spectroscopy (IFS), if coupled with an extreme Adaptive Optics system and analyzed with a Simultaneous Differential Imaging technique (SDI),...

The search for extrasolar giant planets using integral field spectroscopy: Simulations (2006)

Berton, Alessandro, Feldt, Markus, Gratton, Raffaele, Hippler, Stefan, Henning, Thomas

We present here simulations of extrasolar planets detections obtained using a combination of extreme adaptive optics and integral field spectroscopy. The simulation code, written for IDL, provides...

Near-IR observations of UCHII regions (2004)

Alvarez, Carlos, Feldt, Markus, Henning, Thomas, Puga, Elena, Brandner, Wolfgang, Stecklum, Bringfried

We present adaptive-optics (AO) assisted J, H and K/K' images of 8 UCHII regions taken with the ALFA and ADONIS AO systems at Calar Alto and La Silla observatories. The images show details of the...

Hochauflösende Beobachtungen ultrakompakter HII-Gebiete (2003)

Feldt, Markus

Die Arbeit präsentiert Ergebnisse von Breit- und Schmalbandbeobachtungen ultrakompakter HII-Gebiete im nahen und mittleren Infrarot. Erstmals kam im NIR ein System adaptiver Optik (ADONIS am...

Discovery of a candidate for the central star of the ultracompact H II region G5.89-0.39 (2003)

Feldt, Markus, Puga, Elena, Lenzen, Rainer, Henning, Thomas, Brandner, Wolfgang, Stecklum, B., ...

We present high-resolution, near-infrared images of the ultracompact H II region G5.89-0.39 that were taken during a commissioning run of the NACO adaptive optics/near-infrared camera system at the...

Infrared Imaging Polarimetry of Massive Star-forming Regions (2002)

Stecklum, Bringfried, Henning, Thomas, Feldt, Markus, Kaeufl, Hans-Ulrich, Wolf, Sebastian

Imaging polarimetry is a useful tool to reveal the 3D structure of dust distributions and to localize embedded young stellar objects. We present maps of the linear polarization at 2.2 micron for...

High-resolution studies of massive star-forming regions (2001)

Henning, Thomas, Feldt, Markus, Stecklum, Bringfried

We summarize the status of our program of near-infrared adaptive optics observations of ultracompact HII regions. By means of selected results we demonstrate the usefulness of this technique for...