ABSTRACT. The Hectospec is a 300 optical fiber fed spectrograph commissioned at the MMT in the spring of 2004. In the configuration pioneered by the Autofib instrument at the Anglo-Australian Telescope, Hectospec's fiber probes are arranged in a radial "fisherman on the pond" geometry and held in position with small magnets. A pair of high-speed, six-axis robots move the 300 fiber buttons between observing configurations within ∼300 s, and to an accuracy of ∼25 mm. The optical fibers run for 26 m between the MMT's focal surface and the bench spectrograph, operating at . Hectochelle, another high-dispersion bench spectrograph R ∼ 1000-2000 offering , is also available. The system throughput, including all losses in the telescope optics, fibers, R ∼ 35,000 and spectrograph, peaks at ∼10% at the grating blaze in 1Љ FWHM seeing. Correcting for aperture losses at the 1Љ .5 diameter fiber entrance aperture, the system throughput peaks at ∼17%, close to our prediction of 20%. Hectospec has proven to be a workhorse instrument at the MMT. Together, Hectospec and Hectochelle have been scheduled for of the available nights since its commissioning. Hectospec has returned approximately 60,000 1 3 reduced spectra for 16 scientific programs during its first year of operation.

The Hectochelle is an optical band, fiber-fed, multiobject echelle spectrograph deployed at the MMT Observatory on Mount Hopkins, Arizona. The optical fibers that feed the Hectochelle are positioned by the Hectospec robot positioner on the MMT f/5 focal surface, and the Hectochelle shares an optical fiber feed system with the Hectospec, a moderate-dispersion spectrograph that is collocated with the Hectochelle. Hectochelle can record up to 240 spectra simultaneously at a resolution of 38,000. Spectra cover a single diffractive order that is approximately 150 Å wide. The total potential operating passband of the Hectochelle extends from 3800 Å to 9000 Å. Operated in conjunction with the MMT f/5 secondary, the MMT wide-field corrector, and the atmospheric dispersion compensator, the patrol field is 1°in diameter and the individual fiber slits are 1.5′′ in diameter. The throughput of the combined telescope, fiber feed, and spectrograph is measured to be 6.1% at 5275 Å, exclusive of atmospheric extinction. A 20 minute observation of a V ¼ 15 F-type star yields a signal-to-noise ratio of 35 per resolution element. Hectochelle had first light 2003 December 4 and continues to be operated at the MMT today.

A vacuum crystal spectrometer with nominal resolving power approaching 1000 is described for measuring emission lines with wavelength in the extreme ultraviolet region up to 60 Å. The instrument utilizes a flat octadecyl hydrogen maleate crystal and a thin-window 1D position-sensitive gas proportional detector. This detector employs a 1-m-thick 100ϫ 8 mm 2 aluminized polyimide window and operates at one atmosphere pressure. The spectrometer has been implemented on the Livermore electron beam ion traps. The performance of the instrument is illustrated in measurements of the newly discovered magnetic field-sensitive line in Ar 8+ .

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The low energy grating readout for the AXAF-I mission will be implemented with microchannel plates in conjunction with a novel semi-solid substrate strip charge detector. One axis of the charge detector will consist of a conventional wire grid. The other axis will consist of charge pickup strips formed on a ceramic substrate. This configuration will allow the construction of a three segment detector with the approximate curvature of the Rowland circle. A prototype detector has been built and tested. Spatial resolution is commensurate with conventional crossgrid detectors (< 251um FWHM).