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arXiv · 1407.6660

GRAVITY: the Calibration Unit

N. Blind·F. Eisenhauer·M. Haug·S. Gillessen·M. Lippa·L. Burtscher·O. Hans·F. Haussmann·S. Huber·A. Janssen·S. Kellner·Y. Kok·T. Ott·O. Pfuhl·E. Sturm·J. Weber·E. Wieprecht·A. Amorim·W. Brandner·G. Perrin·K. Perraut·C. Straubmeier
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Abstract

We present in this paper the design and characterisation of a new sub-system of the VLTI 2nd generation instrument GRAVITY: the Calibration Unit. The Calibration Unit provides all functions to test and calibrate the beam combiner instrument: it creates two artificial stars on four beams, and dispose of four delay lines with an internal metrology. It also includes artificial stars for the tip-tilt and pupil guiding systems, as well as four metrology pick-up diodes, for tests and calibration of the corresponding sub-systems. The calibration unit also hosts the reference targets to align GRAVITY to the VLTI, and the safety shutters to avoid the metrology light to propagate in the VLTI-lab. We present the results of the characterisation and validtion of these differrent sub-units.

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N. Blind, F. Eisenhauer, M. Haug, S. Gillessen, M. Lippa, L. Burtscher, O. Hans, F. Haussmann, S. Huber, A. Janssen, S. Kellner, Y. Kok, T. Ott, O. Pfuhl, E. Sturm, J. Weber, E. Wieprecht, A. Amorim, W. Brandner, G. Perrin, K. Perraut, C. Straubmeier. 2014-07-24. GRAVITY: the Calibration Unit. https://doi.org/10.1117/12.2055542

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