The PRIMA fringe sensor unit

  title={The PRIMA fringe sensor unit},
  author={Johannes Sahlmann and S{\'e}rge M{\'e}nardi and Roberto Abuter and Matteo Accardo and Sergio Mottini and Francoise Delplancke Eso and Observatoire de Geneve and Thales Alenia Space},
  journal={Astronomy and Astrophysics},
Context. The fringe sensor unit (FSU) is the central element of the phase referenced imaging and micro-arcsecond astrometry (PRIMA) dual-feed facility and provides fringe sensing for all observation modes, comprising off-axis fringe tracking, phase referenced imaging, and high-accuracy narrow-angle astrometry. It is installed at the Very Large Telescope Interferometer (VLTI) and successfully served the fringe-tracking loop during the initial commissioning phase. Aims. To maximise sensitivity… 
First results from fringe tracking with the PRIMA fringe sensor unit
The fringe sensor unit (FSU), the central element of the phase referenced imaging and micro-arcsecond astrometry (PRIMA) dual-feed facility for the Very Large Telescope interferometer (VLTI), is undergoing commissioning and preparation for science operation.
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The Phase Referenced Imaging and Micro Arcsecond Astrometry (PRIMA) facility for the Very Large Telescope Interferometer (VLTI), is being installed and tested in the observatory of Paranal. Most of
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To enable optical long baseline interferometry toward faint objects, long integrations are necessary despite atmospheric turbulence. Fringe trackers are needed to stabilize the fringes and thus
The Nova Fringe Tracker: a second-generation cophasing facility for up to six telescopes at the VLTI
The NOVA Fringe Tracker (NFT) is a proposed solution to the call by ESO for a second generation fringe tracking facility. This instrument at the VLTI will enable the cophasing of up to 6 telescopes
Mid-infrared interferometry with K band fringe-tracking I. The VLTI MIDI+FSU experiment
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Simulation of Kalman-filter fringe tracking with on-sky measurements of the PRIMA Fringe Sensor Unit
The Kalman algorithm as a fringe tacker for GRAVITY is validated and it is found that tracking with the Kalman controller is more efficient than with the PRIMA FSU for all archive data provided by ESO.


Astrometry with the VLTI: calibration of the Fringe Sensor Unit for the PRIMA astrometric camera
Abstract The future PRIMA facility at the Very Large Telescope Interferometer (VLTI) in astrometric mode offers the possibility to perform relative narrow-angle astrometry with 10 micro-arcsecond
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A prototype two-telescope stellar interferometer with a 1.5-m base line has been used to track the white-light fringes from Polaris, thus cancelling the path-length variations caused by earth rotation and atmospheric turbulence.
Post-processing the VLTI fringe-tracking data: first measurements of stars
Context. At the Very Large Telescope Interferometer, the purpose of the fringe-tracker FINITO is to stabilize the optical path differences between the beams, allowing longer integration times on the
AMBER, the near-infrared spectro-interferometric three-telescope VLTI instrument
Context: Optical long-baseline interferometry is moving a crucial step forward with the advent of general-user scientific instruments that equip large aperture and hectometric baseline facilities,
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Fringe Visibility Estimators for the Palomar Testbed Interferometer
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V Phase-Measurement Interferometry Techniques
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We discuss implementation and testing of phase referencing at the Palomar Testbed Interferometer. A new instrument configuration provides a coherent integration of 10 or 20 ms on a bright star while
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