Near-resonance in a System of Sub-Neptunes from TESS

Near-resonance in a System of Sub-Neptunes from TESSQuinn, Samuel N.Becker, Juliette C.Rodriguez, Joseph E.Hadden, SamHuang, Chelsea X.Morton, Timothy D.Adams, Fred C.Armstrong, DavidEastman, Jason D.Horner, JonathanKane, Stephen R.Lissauer, Jack J.Twicken, Joseph D.Vanderburg, AndrewWittenmyer, RobRicker, George R.Vanderspek, Roland K.Latham, David W.Seager, SaraWinn, Joshua N.Jenkins, Jon M.Agol, EricBarkaoui, KhalidBeichman, Charles A.Bouchy, FrançoisBouma, L. G.Burdanov, ArtemCampbell, JenniferCarlino, RobertoCartwright, Scott M.Charbonneau, DavidChristiansen, Jessie L.Ciardi, DavidCollins, Karen A.Collins, Kevin I.Conti, Dennis M.Crossfield, Ian J. M.Daylan, TansuDittmann, JasonDoty, JohnDragomir, DianaDucrot, ElsaGillon, MichaelGlidden, AnaGoeke, Robert F.Gonzales, Erica J.Hełminiak, Krzysztof G.Horch, Elliott P.Howell, Steve B.Jehin, EmmanuelJensen, Eric L. N.Kielkopf, John F.Kristiansen, Martti H.Law, NicholasMann, Andrew W.Marmier, MaximeMatson, Rachel A.Matthews, ElisabethMazeh, TseviMori, MayukoMurgas, FelipeMurray, CatrionaNarita, NorioNielsen, Louise D.Ottoni, GaëlPalle, EnricPawłaszek, RafałPepe, FrancescoPitogo de Leon, JeromePozuelos, Francisco J.Relles, Howard M.Schlieder, Joshua E.Sebastian, DanielSégransan, DamienShporer, AviStassun, Keivan G.Tamura, MotohideUdry, StéphaneWaite, IanWinters, Jennifer G.Ziegler, CarlDOI: info:10.3847/1538-3881/ab3f2bv. 158177
Quinn, Samuel N., Becker, Juliette C., Rodriguez, Joseph E., Hadden, Sam, Huang, Chelsea X., Morton, Timothy D., Adams, Fred C., Armstrong, David, Eastman, Jason D., Horner, Jonathan, Kane, Stephen R., Lissauer, Jack J., Twicken, Joseph D., Vanderburg, Andrew, Wittenmyer, Rob, Ricker, George R., Vanderspek, Roland K., Latham, David W., Seager, Sara, Winn, Joshua N., Jenkins, Jon M., Agol, Eric, Barkaoui, Khalid, Beichman, Charles A., Bouchy, François et al. 2019. "Near-resonance in a System of Sub-Neptunes from TESS." The Astronomical Journal 158:177.
ID: 154591
Type: article
Authors: Quinn, Samuel N.; Becker, Juliette C.; Rodriguez, Joseph E.; Hadden, Sam; Huang, Chelsea X.; Morton, Timothy D.; Adams, Fred C.; Armstrong, David; Eastman, Jason D.; Horner, Jonathan; Kane, Stephen R.; Lissauer, Jack J.; Twicken, Joseph D.; Vanderburg, Andrew; Wittenmyer, Rob; Ricker, George R.; Vanderspek, Roland K.; Latham, David W.; Seager, Sara; Winn, Joshua N.; Jenkins, Jon M.; Agol, Eric; Barkaoui, Khalid; Beichman, Charles A.; Bouchy, François; Bouma, L. G.; Burdanov, Artem; Campbell, Jennifer; Carlino, Roberto; Cartwright, Scott M.; Charbonneau, David; Christiansen, Jessie L.; Ciardi, David; Collins, Karen A.; Collins, Kevin I.; Conti, Dennis M.; Crossfield, Ian J. M.; Daylan, Tansu; Dittmann, Jason; Doty, John; Dragomir, Diana; Ducrot, Elsa; Gillon, Michael; Glidden, Ana; Goeke, Robert F.; Gonzales, Erica J.; Hełminiak, Krzysztof G.; Horch, Elliott P.; Howell, Steve B.; Jehin, Emmanuel; Jensen, Eric L. N.; Kielkopf, John F.; Kristiansen, Martti H.; Law, Nicholas; Mann, Andrew W.; Marmier, Maxime; Matson, Rachel A.; Matthews, Elisabeth; Mazeh, Tsevi; Mori, Mayuko; Murgas, Felipe; Murray, Catriona; Narita, Norio; Nielsen, Louise D.; Ottoni, Gaël; Palle, Enric; Pawłaszek, Rafał; Pepe, Francesco; Pitogo de Leon, Jerome; Pozuelos, Francisco J.; Relles, Howard M.; Schlieder, Joshua E.; Sebastian, Daniel; Ségransan, Damien; Shporer, Avi; Stassun, Keivan G.; Tamura, Motohide; Udry, Stéphane; Waite, Ian; Winters, Jennifer G.; Ziegler, Carl
Abstract: We report the Transiting Exoplanet Survey Satellite detection of a multi-planet system orbiting the V = 10.9 K0 dwarf TOI-125. We find evidence for up to five planets, with varying confidence. Three transit signals with high signal-to-noise ratio correspond to sub-Neptune-sized planets (2.76, 2.79, and 2.94 R ), and we statistically validate the planetary nature of the two inner planets (P b = 4.65 days, P c = 9.15 days). With only two transits observed, we report the outer object (P .03 = 19.98 days) as a planet candidate with high signal-to-noise ratio. We also detect a candidate transiting super-Earth (1.4 R ) with an orbital period of only 12.7 hr and a candidate Neptune-sized planet (4.2 R ) with a period of 13.28 days, both at low signal-to-noise ratio. This system is amenable to mass determination via radial velocities and transit-timing variations, and provides an opportunity to study planets of similar size while controlling for age and environment. The ratio of orbital periods between TOI-125 b and c (P c /P b = 1.97) is slightly lower than an exact 2:1 commensurability and is atypical of multiple planet systems from Kepler, which show a preference for period ratios just wide of first-order period ratios. A dynamical analysis refines the allowed parameter space through stability arguments and suggests that despite the nearly commensurate periods, the system is unlikely to be in resonance.