The L 98-59 System: Three Transiting, Terrestrial-Sized Planets Orbiting a Nearby M-dwarf
Creators: name: Kostov, Veselin B.
name: Schlieder, Joshua E.
name: Barclay, Thomas
name: Quintana, Elisa V.
name: Colon, Knicole D.
name: Brande, Jonathan
name: Collins, Karen A.
name: Feinstein, Adina D.
name: Hadden, Samuel
name: Kane, Stephen R.
name: Kreidberg, Laura
name: Kruse, Ethan
name: Lam, Christopher
name: Matthews, Elisabeth
name: Montet, Benjamin T.
name: Pozuelos, Francisco J.
name: Stassun, Keivan G.
name: Winters, Jennifer G.
name: Ricker, George
name: Vanderspek, Roland
name: Latham, David
name: Seager, Sara
name: Winn, Joshua
name: Jenkins, Jon M.
name: Afanasev, Dennis
name: Armstrong, James J. D.
name: Arney, Giada
name: Boyd, Patricia
name: Barentsen, Geert
name: Barkaoui, Khalid
name: Batalha, Natalie E.
name: Beichman, Charles
name: Bayliss, Daniel
name: Burke, Christopher
name: Burdanov, Artem
name: Cacciapuoti, Luca
name: Carson, Andrew
name: Charbonneau, David
name: Christiansen, Jessie
name: Ciardi, David
name: Clampin, Mark
name: Collins, Kevin I.
name: Conti, Dennis M.
name: Coughlin, Jeffrey
name: Covone, Giovanni
name: Crossfield, Ian
name: Delrez, Laetitia
name: Domagal-Goldman, Shawn
name: Dressing, Courtney
name: Ducrot, Elsa
name: Essack, Zahra
name: Everett, Mark E.
name: Fauchez, Thomas
name: Foreman-Mackey, Daniel
name: Gan, Tianjun
name: Gilbert, Emily
name: Gillon, Michael
name: Gonzales, Erica
name: Hamann, Aaron
name: Hedges, Christina
name: Hocutt, Hannah
name: Hoffman, Kelsey
name: Horch, Elliott P.
name: Horne, Keith
name: Howell, Steve
name: Hynes, Shane
name: Ireland, Michael
name: Irwin, Jonathan M.
name: Isopi, Giovanni
name: Jensen, Eric L. N.
name: Jehin, Emmanuel
name: Kaltenegger, Lisa
name: Kielkopf, John F.
name: Kopparapu, Ravi
name: Lewis, Nikole
name: Lopez, Eric
name: Lissauer, Jack J.
name: Mann, Andrew W.
name: Mallia, Franco
name: Mandell, Avi
name: Matson, Rachel A.
name: Mazeh, Tsevi
name: Monsue, Teresa
name: Moran, Sarah E.
name: Moran, Vickie
name: Morley, Caroline V.
name: Morris, Brett
name: Muirhead, Philip
name: Mukai, Koji
name: Mullally, Susan
name: Mullally, Fergal
name: Murray, Catriona
name: Narita, Norio
name: alle, EnricP
name: Pidhorodetska, Daria
name: Quinn, David
name: Relles, Howard
name: Rinehart, Stephen
name: Ritsko, Matthew
name: Rodriguez, Joseph E.
name: Rowden, Pamela
name: Rowe, Jason F.
name: Sebastian, Daniel
name: Sefako, Ramotholo
name: Shahaf, Sahar
name: Shporer, Avi
name: Reyes, Naylynn Tanon
name: Tenenbaum, Peter
name: Ting, Eric B.
name: Twicken, Joseph D.
name: van Belle, Gerard T.
name: Vega, Laura
name: Volosin, Jeffrey
name: Walkowicz, Lucianne M.
name: Youngblood, Allison
Publisher: name: arXiv
Year: 2019
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We report the Transiting Exoplanet Survey Satellite (TESS) discovery of three terrestrial-sized planets transiting L 98-59 (TOI-175, TIC 307210830) -- a bright M dwarf at a distance of 10.6 pc. Using the Gaia-measured distance and broad-band photometry we find that the host star is an M3 dwarf. Combined with the TESS transits from three sectors, the corresponding stellar parameters yield planet radii ranging from 0.8REarth to 1.6REarth. All three planets have short orbital periods, ranging from 2.25 to 7.45 days with the outer pair just wide of a 2:1 period resonance. Diagnostic tests produced by the TESS Data Validation Report and the vetting package DAVE rule out common false positive sources. These analyses, along with dedicated follow-up and the multiplicity of the system, lend confidence that the observed signals are caused by planets transiting L 98-59 and are not associated with other sources in the field. The L 98-59 system is interesting for a number of reasons: the host star is bright (V = 11.7 mag, K = 7.1 mag) and the planets are prime targets for further follow-up observations including precision radial-velocity mass measurements and future transit spectroscopy with the James Webb Space Telescope; the near resonant configuration makes the system a laboratory to study planetary system dynamical evolution; and three planets of relatively similar size in the same system present an opportunity to study terrestrial planets where other variables (age, metallicity, etc.) can be held constant. L 98-59 will be observed in 4 more TESS sectors, which will provide a wealth of information on the three currently known planets and have the potential to reveal additional planets in the system.
description: 27 pages, 22 figures, AJ accepted