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تسجيل مستخدم جديدVeloce Rosso: Australias new precision radial velocity spectrograph
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Veloce is an ultra-stable fibre-fed R4 echelle spectrograph for the 3.9 m Anglo-Australian Telescope. The first channel to be commissioned, Veloce Rosso, utilises multiple low-cost design innovations to obtain Doppler velocities for Sun-like and M-dwarf stars at <1 m/s precision. The spectrograph has an asymmetric white-pupil format with a 100-mm beam diameter, delivering R>75,000 spectra over a 580-950 nm range for the Rosso channel. Simultaneous calibration is provided by a single-mode pulsed laser frequency comb in tandem with a traditional arc lamp. A bundle of 19 object fibres provides a 2.4 field of view for full sampling of stellar targets from the AAT site. Veloce is housed in dual environmental enclosures that maintain positive air pressure at a stability of +/-0.3 mbar, with a thermal stability of +/-0.01 K on the optical bench. We present a technical overview and early performance data from Australias next major spectroscopic machine.
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