A high-resolution Fourier transform spectrometer for astronomical observations and development of wavelength standards

摘要

At the Institute for Astrophysics Goettingen (IAG), we are purchasing a high resolutionFourier Transform Spectrograph (FTS) for astronomical observations and development ofcalibration standards aiming at high wavelength precision. Astronomical spectrographsthat work in the regime of very high resolution (resolving powers λ/δλ≥10sup5/sup) now achieveunprecedented precision and stability. Precise line shifts can be investigated to conclude foran objects radial velocity relative to the observer. As a long-term scientific goal, the evolutionof galaxy redshift due to dark energy can be monitored. Also, the detection of lower mass,down to Earth-like planets will become feasible. Here, M-dwarfs are promising objects wherean orbiting exo-Earth can cause a wavelength shift large enough to be detected. Emittingmainly in the near infrared (NIR), these objects require novel calibration standards. Currentschemes under consideration are gas cathode lamps (e.g. CN, UNe) and a highly stableFabry-Perot interferometer (FPI) to act as a cost-efficient alternative to the laser frequencycomb (LFC, [1]). In addition to experiments exploring novel wavelength calibration types,light will be fed from our telescopes at IAG. A Vacuum Tower Telescope (VTT) for solarobservations and the 50 cm Cassegrain telescope allow to investigate stellar and spatiallyresolved light at our facilities.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.