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arXiv · 1501.05822

The GRAVITY instrument software / High-level software

Leonard Burtscher·Ekkehard Wieprecht·Thomas Ott·Yitping Kok·Senol Yazici·Narsireddy Anugu·Roderick Dembet·Pierre Fedou·Sylvestre Lacour·Juergen Ott·Thibaut Paumard·Vincent Lapeyrere·Pierre Kervella·Roberto Abuter·Eszter Pozna·Frank Eisenhauer·Nicolas Blind·Reinhard Genzel·Stefan Gillessen·Oliver Hans·Marcus Haug·Frank Haussmann·Stefan Kellner·Magdalena Lippa·Oliver Pfuhl·Eckhard Sturm·Johannes Weber·Antonio Amorim·Wolfgang Brandner·Karine Rousselet-Perraut·Guy S. Perrin·Christian Straubmeier·Markus Schoeller
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Abstract

GRAVITY is the four-beam, near- infrared, AO-assisted, fringe tracking, astrometric and imaging instrument for the Very Large Telescope Interferometer (VLTI). It is requiring the development of one of the most complex instrument software systems ever built for an ESO instrument. Apart from its many interfaces and interdependencies, one of the most challenging aspects is the overall performance and stability of this complex system. The three infrared detectors and the fast reflective memory network (RMN) recorder contribute a total data rate of up to 20 MiB/s accumulating to a maximum of 250 GiB of data per night. The detectors, the two instrument Local Control Units (LCUs) as well as the five LCUs running applications under TAC (Tools for Advanced Control) architecture, are interconnected with fast Ethernet, RMN fibers and dedicated fiber connections as well as signals for the time synchronization. Here we give a simplified overview of all subsystems of GRAVITY and their interfaces and discuss two examples of high-level applications during observations: the acquisition procedure and the gathering and merging of data to the final FITS file.

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Leonard Burtscher, Ekkehard Wieprecht, Thomas Ott, Yitping Kok, Senol Yazici, Narsireddy Anugu, Roderick Dembet, Pierre Fedou, Sylvestre Lacour, Juergen Ott, Thibaut Paumard, Vincent Lapeyrere, Pierre Kervella, Roberto Abuter, Eszter Pozna, Frank Eisenhauer, Nicolas Blind, Reinhard Genzel, Stefan Gillessen, Oliver Hans, Marcus Haug, Frank Haussmann, Stefan Kellner, Magdalena Lippa, Oliver Pfuhl, Eckhard Sturm, Johannes Weber, Antonio Amorim, Wolfgang Brandner, Karine Rousselet-Perraut, Guy S. Perrin, Christian Straubmeier, Markus Schoeller. 2015-01-23. The GRAVITY instrument software / High-level software. https://doi.org/10.1117/12.2055928

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