Transit Timing Variations for AU Microscopii b &amp; c
Creators: name: Wittrock, Justin M.
name: Dreizler, Stefan
name: Reefe, Michael
name: Plavchan, Peter
name: Gilbert, Emily A.
name: Barclay, Thomas
name: Morris, Brett M.
name: Demory, Brice-Olivier
name: Dragomir, Diana
name: Crossfield, Ian J. M.
name: Ingalls, James
name: Lowrance, Patrick
name: Gao, Peter
name: Kaye, Laurel
name: Wang, Songhu
name: Newton, Elisabeth R.
name: Gaidos, Eric
name: Cale, Bryson L.
name: El Mufti, Mohammed
name: Collins, Kevin I.
name: Kane, Stephen R.
name: Tanner, Angelle
name: Gagné, Jonathan
name: Quintana, Elisa V.
name: Vega, Laura D.
name: Schlieder, Joshua E.
name: Monsue, Teresa
name: Hebb, Leslie
name: Stassun, Keivan G.
name: Roccatagliata, Veronica
name: Schwarz, Richard P.
name: Tan, T. G.
name: Radford, Don J.
name: Stockdale, Christopher
Publisher: name: Zenodo
Year: 2021
Subjects: Exoplanets
Stars: activity
Stars: individual: AU Mic
Techniques: photometric
Techniques: transit
Techniques: transit timing variation

description: AU Mic is a relatively bright, nearby (9.7 pc), young (22 Myr) M1V pre-main sequence star hosting two transiting exoplanets AU Mic b and c and a spatially-resolved outer dusty debris disk. This research explores the transit timing variations (TTVs) of AU Mic b and c. For AU Mic b, we present three Spitzer/IRAC (4.5 μm) transits (two new), five TESS Cycle 1 and 3 transits, 11 LCO transits, one PEST-0.30m transit, one Brierfield-0.36m transit, and two transit timing measurements from Rossiter-McLaughlin observations; for AU Mic c, we present three TESS Cycle 1 and 3 transits. We use EXOFASTv2 to jointly model the transits and to obtain the midpoint transit times. We then construct an O-C diagram to map the TTVs. We model the TTVs for AU Mic b and c with Exo-Striker to recover constraints on the mass for AU Mic c. We compare the TTV-derived constraints to a recent radial-velocity mass determination. The results demonstrate that the AU Mic planetary system is dynamically interacting producing detectable TTVs, and the implied orbital dynamics may inform future constraints on the formation mechanisms for this young planetary system. However, stellar activity from flares and rotational spot modulation complicate our analysis of this young system. We recommend future TTV observations of AU Mic b and c to further constrain the dynamical masses and to search for additional planets in the system.
description: {"references": ["Agol, E., Steffen, J., Sari, R., &amp; Clarkson, W. 2005, MNRAS, 359, 567, doi: 10.1111/j.1365-2966.2005.08922.x", "Akeson, R. L., Chen, X., Ciardi, D., et al. 2013, PASP, 125, 989, doi: 10.1086/672273", "Bailer-Jones, C. A. L., Rybizki, J., Fouesneau, M., Mantelet, G., &amp; Andrae, R. 2018, AJ, 156, 58, doi: 10.3847/1538-3881/aacb21", "Becker, J. C., Vanderburg, A., Adams, F. C., Rappaport, S. A., &amp; Schwengeler, H. M. 2015, ApJL, 812, L18, doi: 10.1088/2041-8205/812/2/L18", "Butler, C. J., Byrne, P. B., Andrews, A. D., &amp; Doyle, J. G. 1981, MNRAS, 197, 815, doi: 10.1093/mnras/197.3.815", "Cale, B., Reefe, M., Plavchan, P., et al. 2021, submitted", "Collins, K. A., Kielkopf, J. F., Stassun, K. G., &amp; Hessman, F. V. 2017, AJ, 153, 77, doi: 10.3847/1538-3881/153/2/77", "Cully, S. L., Siegmund, O. H. W., Vedder, P. W., &amp; Vallerga, J. V. 1993, ApJL, 414, L49, doi: 10.1086/186993", "Eastman, J. D., Rodriguez, J. E., Agol, E., et al. 2019, arXiv e-prints, arXiv:1907.09480.https://arxiv.org/abs/1907.09480", "Gilbert, E. A., Barclay, T., Quintana, E., et al. 2021, submitted", "Gillon, M., Triaud, A. H. M. J., Demory, B.-O.,et al. 2017, Nature, 542, 456, doi: 10.1038/nature21360", "Grimm, S. L., Demory, B.-O., Gillon, M., et al. 2018, A&amp;A, 613, A68, doi: 10.1051/0004-6361/201732233", "Holman, M. J., &amp; Murray, N. W. 2005, Science, 307, 1288, doi: 10.1126/science.1107822", "Kalas, P., Liu, M. C., &amp; Matthews, B. C. 2004, Science, 303, 1990, doi: 10.1126/science.1093420", "Kundu, M. R., Jackson, P. D., White, S. M., &amp; Melozzi, M. 1987, ApJ, 312, 822, doi: 10.1086/164928", "Mamajek, E. E., &amp; Bell, C. P. M. 2014, MNRAS, 445, 2169, doi: 10.1093/mnras/stu1894", "Martioli, E., H\u00e9brard, G., Moutou, C., et al. 2020, A&amp;A, 641, L1,doi: 10.1051/0004-6361/202038695", "Mazeh, T., Nachmani, G., Holczer, T., et al. 2013, ApJS, 208, 16, doi: 10.1088/0067-0049/208/2/16", "Palle, E., Oshagh, M., Casasayas-Barris, N., et al. 2020, A&amp;A, 643, A25, doi: 10.1051/0004-6361/202038583", "Plavchan, P., Barclay, T., Gagn\u00e9, J., et al. 2020, Nature, 582, 497, doi: 10.1038/s41586-020-2400-z", "Trifonov, T. 2019, The Exo-Striker: Transit and radial velocity interactive fitting tool for orbital analysis and N-body simulations. http://ascl.net/1906.004", "Wittrock, J., Dreizler, S., Reefe, M., et al. 2021, in preparation"]}