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تسجيل مستخدم جديدHectospec, the MMTs 300 Optical Fiber-Fed Spectrograph
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The Hectospec is a 300 optical fiber fed spectrograph commissioned at the MMT in the spring of 2004. A pair of high-speed six-axis robots move the 300 fiber buttons between observing configurations within ~300 s and to an accuracy ~25 microns. The optical fibers run for 26 m between the MMTs focal surface and the bench spectrograph operating at R~1000-2000. Another high dispersion bench spectrograph offering R~5,000, Hectochelle, is also available. The system throughput, including all losses in the telescope optics, fibers, and spectrograph peaks at ~10% at the grating blaze in 1 FWHM seeing. Correcting for aperture losses at the 1.5 diameter fiber entrance aperture, the system throughput peaks at $sim$17%. Hectospec has proven to be a workhorse instrument at the MMT. Hectospec and Hectochelle together were scheduled for 1/3 of the available nights since its commissioning. Hectospec has returned ~60,000 reduced spectra for 16 scientific programs during its first year of operation.
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