Non-detection of Contamination by Stellar Activity in the Spitzer Transit Light Curves of TRAPPIST-1

  title={Non-detection of Contamination by Stellar Activity in the Spitzer Transit Light Curves of TRAPPIST-1},
  author={Brett M. Morris and Eric Agol and Leslie Hebb and Suzanne L. Hawley and Micha{\"e}l Gillon and Elsa Ducrot and Laetitia Delrez and James G. Ingalls and B-O. Demory},
  journal={The Astrophysical Journal},
We apply the transit light curve self-contamination technique of Morris et al. (2018) to search for the effect of stellar activity on the transits of the ultracool dwarf TRAPPIST-1 with 2018 Spitzer photometry. The self-contamination method fits the transit light curves of planets orbiting spotted stars, allowing the host star to be a source of contaminating positive or negative flux which influences the transit depths but not the ingress/egress durations. We find that none of the planets show… 

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