We present a new analysis of the light curve of the young planet-hosting star TOI 451 in the light of new observations from TESS Cycle 3. Our joint analysis of the transits of all three planets, using all available TESS data, results in an improved ephemeris for TOI 451 b and TOI 451 c, which will help to plan follow-up observations. The updated mid-transit times are BJD−2,457000=1410.9896−0.0029+0.0032, 1411.7982−0.0020+0.0022, and 1416.63407−0.00100+0.00096 for TOI 451 b, c, and d, respectively, and the periods are 1.8587028−10e−06+08e−06, 9.192453−3.3e−05+4.1e−05, and 16.364932−3.5e−05+3.6e−05 days. We also model the out-of-transit light curve using a Gaussian Process with a quasi-periodic kernel and infer a change in the properties of the active regions on the surface of TOI 451 between TESS Cycles 1 and 3.
@article{arxiv.2103.09746,
title = {TESS re-observes the young multi-planet system TOI-451: refined ephemeris and activity evolution},
author = {Oscar Barragán and Suzanne Aigrain and Edward Gillen and Fernando Gutiérrez-Canales},
journal= {arXiv preprint arXiv:2103.09746},
year = {2021}
}