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Paper: Implementation of the Global Parameters Determination in Gaia’s Astrometric Solution (AGIS)
Volume: 434, Astronomical Data Analysis Software and Systems XIX
Page: 386
Authors: Raison, F.; Olias, A.; Hobbs, D.; Lindegren, L.
Abstract: Gaia is ESA’s space astrometry mission with a foreseen launch date in early 2012. Its main objective is to perform a stellar census of the 1000 Million brightest objects in our galaxy (completeness to V=20 mag) from which an astrometric catalog of micro-arcsec level accuracy will be constructed. A key element in this endeavor is the Astrometric Global Iterative Solution (AGIS). A core part of AGIS is to determine the accurate spacecraft attitude, geometric instrument calibration and astrometric model parameters for a well-behaved subset of all the objects (the ‘primary stars’). In addition, a small number of global parameters will be estimated, one of these being PPN γ. We present here the implementation of the algorithms dedicated to the determination of the global parameters.
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