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تسجيل مستخدم جديدThe Milky Ways halo in 6D: Gaias Radial Velocity Spectrometer performance
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George Seabroke
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Gaias Radial Velocity Spectrometer (RVS) has been operating in routine phase for over one year since initial commissioning. RVS continues to work well but the higher than expected levels of straylight reduce the limiting magnitude. The end-of-mission radial-velocity (RV) performance requirement for G2V stars was 15 km/s at V = 16.5 mag. Instead, 15 km/s precision is achieved at 15 < V < 16 mag, consistent with simulations that predict a loss of 1.4 mag. Simulations also suggest that changes to Gaias onboard software could recover ~0.14 mag of this loss. Consequently Gaias onboard software was upgraded in April 2015. The status of this new commissioning period is presented, as well as the latest scientific performance of the on-ground processing of RVS spectra. We illustrate the implications of the RVS limiting magnitude on Gaias view of the Milky Ways halo in 6D using the Gaia Universe Model Snapshot (GUMS).
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