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تسجيل مستخدم جديدThe Pointing Limits of Transiting Exoplanet Light Curve Characterization with Pixel Level De-correlation
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We present scope (Simulated CCD Observations for Photometric Experimentation), a Python package to create a forward model of telescope detectors and simulate stellar targets with motion relative to the CCD. The primary application of this package is the simulation of the Kepler Space Telescope detector to predict and characterize increased instrumental noise in the spacecrafts final campaigns of observation. As the fuel powering the spacecrafts stabilizing thrusters ran out and thruster fires began to sputter and fail, stellar Point Spread Functions (PSFs) experienced more extreme and less predictable motion relative to regions of varied sensitivity on the spacecraft detector, generating more noise in transiting exoplanet light curves. Using our simulations, we demonstrate that current de-trending techniques effectively capture and remove systematics caused by sensitivity variation for spacecraft motion as high as about ten times that typically experienced by K2. The scope package is open-source and has been generalized to allow custom detector and stellar target parameters. Future applications include simulating observations made by the Transiting Exoplanet Survey Satellite (TESS) and ground based observations with synthetic atmospheric interference as testbeds for noise-removal techniques.
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