A New Method for Calibration of Gain Variation in Detector System

摘要: Transit spectroscopy of habitable planets orbiting late-type stars requires high relative spectro-photometric accuracy between wavelengths during transit/eclipse observation. The signal is not affected only by image movement and deformation due to wavefront error but also electrical variation in the detector system. These time-variation components, coupled transit signal, distort measurements atmospheric composition spectroscopy. Here we propose a new concept for improvement through calibration components system developing densified pupil that provides multiple spectra star-planet Owing group pixels exposed object light (i.e., science pixels), pixel-to-pixel variations can be smoothed out an averaging operation, thus common over remain. In addition, considering plane optically conjugated plane, mask completely block astronomical incoming into residual pixels. are reconstructed with reduced random term. Applying spectrograph mid-infrared large space cryogenic telescope such as Origins Space Telescope, show nearly achieves photon-noise-limited performance detects absorption features transmission secondary eclipse terrestrial M-type at 10 pc 60 observations. Thus, proposed method contributes measurement planetary habitability biosignatures nearby transiting candidates.