The investigators will design, fabricate, calibrate, and commission a portable Compact Echelle Spectrograph for Aeronomical Research (CESAR), with 310 -1040 nm wavelength coverage, a resolution of 1/20,000 of the wavelength, and sensitivity specifically tailored to meet the needs of atmospheric researchers. In order to provide the enhanced spatial coverage required for atmospheric research, the CESAR will sample spectra from a 7 degree to 20 degree field-of-view slit with all-sky coverage and arbitrary slit orientation. The CESAR is designed for autonomous operation with support needs limited to power and internet access. Because of the great improvement in spectral resolution, sensitivity, response time, and the instrument's transportability, the spectrograph will enable new investigations of the dynamics, physics, and chemistry from the stratosphere to the exosphere. Co-locating the instrument with NSF's Advanced Modular Incoherent Scatter Radar (AMISR), currently situated at Alaska's Poker Flat Research Range, would enable detailed evaluation of the energy transfer between ions and neutrals and the vertical coupling of atmospheric regions within and below the aurora. By monitoring a broad range of wavelengths simultaneously, the changes in atmospheric composition following an aurora may be monitored as well as the primary electron energy driving the aurora. Alaska is also the site of the HAARP ionospheric heating facility, which would benefit from the additional diagnostic information provided by the instrument's high resolution and broad spectral range. The transportability of the instrument allows it to participate in non-auroral observational campaigns such as investigations of ionospheric bubbles occurring at Bear Lake Observatory in Utah, where it would contribute information on simultaneous emissions from important atomic and molecular species, and investigations of the mechanisms for long-lived meteor trains. SRI is committed to developing the CESAR so as to train students, stimulate new avenues of atmospheric investigation, and strengthen the support base for academic research. A CESAR development team has been formed with researchers from six universities to craft design and commissioning goals which will maximize the involvement of graduate students, postdoctoral fellows, and faculty level atmospheric researchers. Academic and industrial team members will give new students and postdoctoral fellows hands-on experience during CESAR fabrication. Senior personnel from the University of Alaska, Cornell University, University of Illinois, and Utah State University have created a set of science goals for CESAR at the Poker Flat Rocket Range (PFRR) in Fairbanks, Alaska. These goals will leverage CESAR's unique capabilities by investigating electron and proton precipitation, auroral impact on atmospheric composition, meteoric chemistry, and atomic oxygen response to thermospheric heating. The CESAR instrument will have a lasting effect on our nation's research infrastructure by enabling remote access by academic researchers to high value spectroscopic data from remote, yet geophysically significant regimes. This project will also reinvigorate the connections between space science field research and supportive physical chemistry laboratory studies.
