Details

Autor(en) / Beteiligte

• Gilbert, Emily A.
• Barclay, Thomas
• Quintana, Elisa V.
• Walkowicz, Lucianne M.
• Vega, Laura D.
• Schlieder, Joshua E.
• Monsue, Teresa
• Cale, Bryson L.
• Collins, Kevin I.
• Gaidos, Eric
• El Mufti, Mohammed
• Reefe, Michael A.
• Plavchan, Peter
• Tanner, Angelle
• Wittenmyer, Robert A.
• Wittrock, Justin M.
• Jenkins, Jon M.
• Latham, David W.
• Ricker, George R.
• Rose, Mark E.
• Seager, S.
• Vanderspek, Roland K.
• Winn, Joshua N.

Titel

Flares, Rotation, and Planets of the AU Mic System from TESS Observations

Ist Teil von

• The Astronomical journal, 2022-04, Vol.163 (4), p.147

Ort / Verlag

Madison: The American Astronomical Society

Erscheinungsjahr

2022

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Abstract AU Mic is a young (∼24 Myr), pre-main-sequence M dwarf star that was observed in the first month of science observations of the Transiting Exoplanet Survey Satellite (TESS) and reobserved 2 years later. This target has photometric variability from a variety of sources that is readily apparent in the TESS light curves; spots induce modulation in the light curve, flares are present throughout (manifesting as sharp rises with slow exponential decay phases), and transits of AU Mic b may be seen by eye as dips in the light curve. We present a combined analysis of both TESS Sector 1 and Sector 27 AU Mic light curves including the new 20 s cadence data from TESS Year 3. We compare flare rates between both observations and analyze the spot evolution, showing that the activity levels increase slightly from Sector 1 to Sector 27. Furthermore, the 20 s data collection allows us to detect more flares, smaller flares, and better resolve flare morphology in white light as compared to the 2 minute data collection mode. We also refine the parameters for AU Mic b by fitting three additional transits of AU Mic b from Sector 27 using a model that includes stellar activity. We show that the transits exhibit clear transit timing variations with an amplitude of ∼80 s. We also detect three transits of a 2.8 R ⊕ planet, AU Mic c, which has a period of 18.86 days.