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Hrynevych, Michael A.

Publications and source records attributed to Hrynevych, Michael A..

Mechanical Design of NESSI: New Mexico Tech Extrasolar Spectroscopic Survey Instrument

NESSI: the New Mexico Tech Extrasolar Spectroscopic Survey Instrument is a ground-based multi-object spectrograph that operates in the near-infrared. It will be installed on one of the Nasmyth ports of the Magdalena Ridge Observatory (MRO) 2.4-meter Telescope sited in the Magdalena Mountains, about 48 km west of Socorro-NM. NESSI operates stationary to the telescope fork so as not to produce differential flexure between internal opto-mechanical components during or between observations. An appropriate mechanical design allows the instrument alignment to be highly repeatable and stable for both short and long observation timescales, within a wide-range of temperature variation. NESSI is optically composed of a field lens, a field de-rotator, re-imaging optics, an auto-guider and a Dewar spectrograph that operates at LN2 temperature. In this paper we report on NESSI's detailed mechanical and opto-mechanical design, and the planning for mechanical construction, assembly, integration and verification.

exoplanet

Keck Interferometer autoaligner : algorithms and techniques

The Keck Interferometer includes an autoalignment system consisting of pop-up targets located at strategic locations along the beam trains of each arm of the instrument along with a sensor and control system. We briefly describe the hardware of the system and then proceed to a description of the two operational modes of the system.

Interferometry

Baseline Monitoring for Astrometry in Interferometry

One of the science goals of NASA's Navigator program is ground-based narrow-angle astrometry for extra-solar planet detection, which could be done as part of the proposed Outrigger Telescopes Project. The narrow-angle measurement process, which would use the outrigger telescopes, starts with the determination of the conventional interferometer astrometric baseline, determined from wide-angle astrometry of Hipparcos stars. A baseline monitor system would be employed at each outrigger telescope. This system monitors the pivot point of each telescope - the end point of the astrometric baseline - to measure telescope imperfections that would cause the baseline to vary with telescope rotation. The baseline monitor includes azimuth and elevation cameras that monitor runout along the azimuth and elevation axes of the telescopes. In conjunction with the baseline monitor system, a pivot monitor camera in the dual-star module is used to register the laser metrology corner-cube reflector to the telescope pivot, tying the narrow-angle baseline, which applies to the narrow-angle astrometric measurement, to the wide-angle baseline. In this paper we present the proposed designs for the baseline monitor and pivot-point camera.

pivot point