|   | 
Author Carleo, I.; Gandolfi, D.; Barragan, O.; Livingston, J.H.; Persson, C.M.; Lam, K.W.F.; Vidotto, A.; Lund, M.B.; D'Angelo, C.V.; Collins, K.A.; Fossati, L.; Howard, A.W.; Kubyshkina, D.; Brahm, R.; Oklopcic, A.; Molliere, P.; Redfield, S.; Serrano, L.M.; Dai, F.; Fridlund, M.; Borsa, F.; Korth, J.; Esposito, M.; Diaz, M.R.; Nielsen, L.D.; Hellier, C.; Mathur, S.; Deeg, H.J.; Hatzes, A.P.; Benatti, S.; Rodler, F.; Alarcon, J.; Spina, L.; Santos, A.R.G.; Georgieva, I.; Garcia, R.A.; Gonzalez-Cuesta, L.; Ricker, G.R.; Vanderspek, R.; Latham, D.W.; Seager, S.; Winn, J.N.; Jenkins, J.M.; Albrecht, S.; Batalha, N.M.; Beard, C.; Boyd, P.T.; Bouchy, F.; Burt, J.A.; Butler, R.P.; Cabrera, J.; Chontos, A.; Ciardi, D.R.; Cochran, W.D.; Collins, K.I.; Crane, J.D.; Crossfield, I.; Csizmadia, S.; Dragomir, D.; Dressing, C.; Eigmuller, P.; Endl, M.; Erikson, A.; Espinoza, N.; Fausnaugh, M.; Feng, F.B.; Flowers, E.; Fulton, B.; Gonzales, E.J.; Grieves, N.; Grziwa, S.; Guenther, E.W.; Guerrero, N.M.; Henning, T.; Hidalgo, D.; Hirano, T.; Hjorth, M.; Huber, D.; Isaacson, H.; Jones, M.; Jordan, A.; Kabath, P.; Kane, S.R.; Knudstrup, E.; Lubin, J.; Luque, R.; Mireles, I.; Narita, N.; Nespral, D.; Niraula, P.; Nowak, G.; Palle, E.; Patzold, M.; Petigura, E.A.; Prieto-Arranz, J.; Rauer, H.; Robertson, P.; Rose, M.E.; Roy, A.; Sarkis, P.; Schlieder, J.E.; Segransan, D.; Shectman, S.; Skarka, M.; Smith, A.M.S.; Smith, J.C.; Stassun, K.; Teske, J.; Twicken, J.D.; Van Eylen, V.; Wang, S.R.; Weiss, L.M.; Wyttenbach, A.
Title The Multiplanet System TOI-421* Type
Year 2020 Publication Astronomical Journal Abbreviated Journal Astron. J.
Volume 160 Issue 3 Pages 23 pp
Abstract We report the discovery of a warm Neptune and a hot sub-Neptune transiting TOI-421 (BD-14 1137, TIC 94986319), a bright (V = 9.9) G9 dwarf star in a visual binary system observed by the Transiting Exoplanet Survey Satellite (TESS) space mission in Sectors 5 and 6. We performed ground-based follow-up observations-comprised of Las Cumbres Observatory Global Telescope transit photometry, NIRC2 adaptive optics imaging, and FIbre-fed Echelle Spectrograph, CORALIE, High Accuracy Radial velocity Planet Searcher, High Resolution echelle Spectrometer, and Planet Finder Spectrograph high-precision Doppler measurements-and confirmed the planetary nature of the 16 day transiting candidate announced by the TESS team. We discovered an additional radial velocity signal with a period of five days induced by the presence of a second planet in the system, which we also found to transit its host star. We found that the inner mini-Neptune, TOI-421 b, has an orbital period of P-b = 5.19672 +/- 0.00049 days, a mass of M-b = 7.17 +/- 0.66 M-circle plus, and a radius of R-b = R-circle plus, whereas the outer warm Neptune, TOI-421 c, has a period of P-c = 16.06819 +/- 0.00035 days, a mass of M-c = 16.42(-1.04)(+1.06)M(circle plus), a radius of R-c = 5.09(-0.15)(+0.16)R(circle plus), and a density of rho(c) = 0.685(-0.072)(+0.080) cm(-3). With its characteristics, the outer planet (rho(c) = 0.685(-0.0072)(+0.080) cm(-3)) is placed in the intriguing class of the super-puffy mini-Neptunes. TOI-421 b and TOI-421 c are found to be well-suited for atmospheric characterization. Our atmospheric simulations predict significant Ly alpha transit absorption, due to strong hydrogen escape in both planets, as well as the presence of detectable CH4 in the atmosphere of TOI-421 c if equilibrium chemistry is assumed.
Address [Carleo, Ilaria; Redfield, Seth] Wesleyan Univ, Astron Dept, Middletown, CT 06459 USA, Email: icarleo@wesleyan.edu
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6256 ISBN Medium
Area Expedition Conference
Notes WOS:000561609000001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1254
Permanent link to this record

Author Osborn, A.; Armstrong, D.J.; Cale, B.; Brahm, R.; Wittenmyer, R.A.; Dai, F.; Crossfield, I.J.M.; Bryant, E.M.; Adibekyan, V.; Cloutier, R.; Collins, K.A.; Mena, E.D.; Fridlund, M.; Hellier, C.; Howell, S.B.; King, G.W.; Lillo-Box, J.; Otegi, J.; Sousa, S.; Stassun, K.G.; Matthews, E.C.; Ziegler, C.; Ricker, G.; Vanderspek, R.; Latham, D.W.; Seager, S.; Winn, J.N.; Jenkins, J.M.; Acton, J.S.; Addison, B.C.; Anderson, D.R.; Ballard, S.; Barrado, D.; Barros, S.C.C.; Batalha, N.; Bayliss, D.; Barclay, T.; Benneke, B.; Berberian, J.; Bouchy, F.; Bowler, B.P.; Briceno, C.; Burke, C.J.; Burleigh, M.R.; Casewell, S.L.; Ciardi, D.; Collins, K.I.; Cooke, B.F.; Demangeon, O.D.S.; Diaz, R.F.; Dorn, C.; Dragomir, D.; Dressing, C.; Dumusque, X.; Espinoza, N.; Figueira, P.; Fulton, B.; Furlan, E.; Gaidos, E.; Geneser, C.; Gill, S.; Goad, M.R.; Gonzales, E.J.; Gorjian, V.; Gunther, M.N.; Helled, R.; Henderson, B.A.; Henning, T.; Hogan, A.; Hojjatpanah, S.; Horner, J.; Howard, A.W.; Hoyer, S.; Huber, D.; Isaacson, H.; Jenkins, J.S.; Jensen, E.L.N.; Jordan, A.; Kane, S.R.; Kidwell, R.C.; Kielkopf, J.; Law, N.; Lendl, M.; Lund, M.; Matson, R.A.; Mann, A.W.; McCormac, J.; Mengel, M.W.; Morales, F.Y.; Nielsen, L.D.; Okumura, J.; Osborn, H.P.; Petigura, E.A.; Plavchan, P.; Pollacco, D.; Quintana, E.V.; Raynard, L.; Robertson, P.; Rose, M.E.; Roy, A.; Reefe, M.; Santerne, A.; Santos, N.C.; Sarkis, P.; Schlieder, J.; Schwarz, R.P.; Scott, N.J.; Shporer, A.; Smith, A.M.S.; Stibbard, C.; Stockdale, C.; Strom, P.A.; Twicken, J.D.; Tan, T.G.; Tanner, A.; Teske, J.; Tilbrook, R.H.; Tinney, C.G.; Udry, S.; Villasenor, J.N.; Vines, J.I.; Wang, S.X.; Weiss, L.M.; West, R.G.; Wheatley, P.J.; Wright, D.J.; Zhang, H.; Zohrabi, F.
Title TOI-431/HIP 26013: a super-Earth and a sub-Neptune transiting a bright, early K dwarf, with a third RV planet Type
Year 2021 Publication Monthly Notices Of The Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.
Volume 507 Issue 2 Pages 2782-2803
Keywords planets and satellites: detection; planets and satellites: fundamental parameters; planets and satellites: individual: (TOI-431, TIC 31374837)
Abstract We present the bright (V-mag = 9.12), multiplanet system TOI-431, characterized with photometry and radial velocities (RVs). We estimate the stellar rotation period to be 30.5 +/- 0.7 d using archival photometry and RVs. Transiting Exoplanet Survey Satellite (TESS) objects of Interest (TOI)-431b is a super-Earth with a period of 0.49 d, a radius of 1.28 +/- 0.04 R-circle plus, a mass of 3.07 +/- 0.35 M-circle plus, and a density of 8.0 +/- 1.0 g cm(-3); TOI-431 d is a sub-Neptune with a period of 12.46 d, a radius of 3.29 +/- 0.09 R-circle plus, a mass of M-circle plus, and a density of 1.36 +/- 0.25 g cm(-3). We find a third planet, TOI-431c, in the High Accuracy Radial velocity Planet Searcher RV data, but it is not seen to transit in the TESS light curves. It has an Msin i of M-circle plus, and a period of 4.85 d. TOI-431d likely has an extended atmosphere and is one of the most well-suited TESS discoveries for atmospheric characterization, while the super-Earth TOI-431b may be a stripped core. These planets straddle the radius gap, presenting an interesting case-study for atmospheric evolution, and TOI-431b is a prime TESS discovery for the study of rocky planet phase curves.
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0035-8711 ISBN Medium
Area Expedition Conference
Notes WOS:000697380800082 Approved
Call Number UAI @ alexi.delcanto @ Serial 1485
Permanent link to this record