Grill, M., Radovan, M., Melchiorri, R., & Slanger, T. G. (2009, December). CESAR Opto-Mechanical Design. In AGU Fall Meeting Abstracts (Vol. 2009, pp. SA23A-1462).
The Compact Echelle Spectrograph for Aeronomical Research (CESAR) covers the wavelength range from 300 to 1000 nm with a spectral resolution of 20,000. It is being constructed at SRI International with funds from the National Science Foundation’s Major Research Instrumentation Program. Our goal is to significantly expand the range of upper atmospheric science investigations (nightglow, aurora, and dayglow emissions) by providing to aeronomers a high-throughput, high-dispersion, large-passband spectrograph by scaling an astronomical grade echelle spectrograph into a portable version capable of siting at multiple geophysically significant stations, heretofore only available to astronomers at a handful of large observatories. We present major aspects of the ongoing opto-mechanical design. The design incorporates lessons learned from the construction of the High Resolution Echelle Spectrometer (HiRES) and the Automated Planet Finder (APF) spectrometer, amongst others. All major optical components are mounted on kinematically fully determined hexapod structures, giving unprecedented three-dimensional adjustment capability. CESAR is designed to operate in an outdoors environment in remote locations such as the Poker Flat Research Range (PFRR) in Alaska. We present an enclosure concept that will allow CESAR to withstand the weather conditions found at such sites while still giving CESAR’s fore-optics full access to the sky.