2019/02/20 by Paul Robertson, Robertson, Paul, Tyler Anderson +62
Earth and Planetary Sciences · Engineering · Chemistry · #Atmospheric Ozone and Climate #Calibration and Measurement Techniques #Spectroscopy and Laser Applications
paper · pdf · doi:10.48550/arxiv.1902.07729
Two key areas of emphasis in contemporary experimental exoplanet science are\nthe detailed characterization of transiting terrestrial planets, and the search\nfor Earth analog planets to be targeted by future imaging missions. Both of\nthese pursuits are dependent on an order-of-magnitude improvement in the\nmeasurement of stellar radial velocities (RV), setting a requirement on\nsingle-measurement instrumental uncertainty of order 10 cm/s. Achieving such\nextraordinary precision on a high-resolution spectrometer requires\nthermo-mechanically stabilizing the instrument to unprecedented levels. Here,\nwe describe the Environment Control System (ECS) of the NEID Spectrometer,\nwhich will be commissioned on the 3.5 m WIYN Telescope at Kitt Peak National\nObservatory in 2019, and has a performance specification of on-sky RV precision\n< 50 cm/s. Because NEID's optical table and mounts are made from aluminum,\nwhich has a high coefficient of thermal expansion, sub-milliKelvin temperature\ncontrol is especially critical. NEID inherits its ECS from that of the\nHabitable-zone Planet Finder (HPF), but with modifications for improved\nperformance and operation near room temperature. Our full-system stability test\nshows the NEID system exceeds the already impressive performance of HPF,\nmaintaining vacuum pressures below 10-6 Torr and an RMS temperature\nstability better than 0.4 mK over 30 days. Our ECS design is fully open-source;\nthe design of our temperature-controlled vacuum chamber has already been made\npublic, and here we release the electrical schematics for our custom\nTemperature Monitoring and Control (TMC) system.\n