TY - JOUR
T1 - TESS spots a mini- interior to a hot saturn in the TOI-2000 system
AU - Sha, Lizhou
AU - Vanderburg, Andrew M.
AU - Huang, Chelsea X.
AU - Armstrong, David J.
AU - Brahm, Rafael
AU - Giacalone, Steven
AU - Wood, Mackenna L.
AU - Collins, Karen A.
AU - Nielsen, Louise D.
AU - Hobson, Melissa J.
AU - Ziegler, Carl
AU - Howell, Steve B.
AU - Torres-Miranda, Pascal
AU - Mann, Andrew W.
AU - Zhou, George
AU - Delgado-Mena, Elisa
AU - Rojas, Felipe I.
AU - Abe, Lyu
AU - Trifonov, Trifon
AU - Adibekyan, Vardan
AU - Sousa, Srgio G.
AU - Fajardo-Acosta, Sergio B.
AU - Guillot, Tristan
AU - Howard, Saburo
AU - Littlefield, Colin
AU - Hawthorn, Faith
AU - Schmider, François Xavier
AU - Eberhardt, Jan
AU - Tan, Thiam Guan
AU - Osborn, Ares
AU - Schwarz, Richard P.
AU - Strøm, Paul
AU - Jordán, Andrs
AU - Wang, Gavin
AU - Henning, Thomas
AU - Massey, Bob
AU - Law, Nicholas
AU - Stockdale, Chris
AU - Furlan, Elise
AU - Srdoc, Gregor
AU - Wheatley, Peter J.
AU - Barrado Navascus, David
AU - Lissauer, Jack J.
AU - Stassun, Keivan G.
AU - Ricker, George R.
AU - Vanderspek, Roland K.
AU - Latham, David W.
AU - Winn, Joshua N.
AU - Seager, Sara
AU - Jenkins, Jon M.
AU - Barclay, Thomas
AU - Bouma, Luke G.
AU - Christiansen, Jessie L.
AU - Guerrero, Natalia
AU - Rose, Mark E.
N1 - Publisher Copyright:
© 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.
PY - 2023/9/1
Y1 - 2023/9/1
N2 - Hot jupiters (P < 10 d, M > 60 M?) are almost always found alone around their stars, but four out of hundreds known have inner companion planets. These rare companions allow us to constrain the hot jupiter's formation history by ruling out high-eccentricity tidal migration. Less is known about inner companions to hot Saturn-mass planets. We report here the discovery of the TOI-2000 system, which features a hot Saturn-mass planet with a smaller inner companion. The mini-neptune TOI-2000 b (2.70 ± 0.15 R?, 11.0 ± 2.4 M?) is in a 3.10-d orbit, and the hot saturn TOI-2000 c (R?, M?) is in a 9.13-d orbit. Both planets transit their host star TOI-2000 (TIC 371188886, V = 10.98, TESS magnitude = 10.36), a metal-rich ([Fe/H] = 0.439) G dwarf 173 pc away. TESS observed the two planets in sectors 9-11 and 36-38, and we followed up with ground-based photometry, spectroscopy, and speckle imaging. Radial velocities from CHIRON, FEROS, and HARPS allowed us to confirm both planets by direct mass measurement. In addition, we demonstrate constraining planetary and stellar parameters with MIST stellar evolutionary tracks through Hamiltonian Monte Carlo under the PyMC framework, achieving higher sampling efficiency and shorter run time compared to traditional Markov chain Monte Carlo. Having the brightest host star in the V band among similar systems, TOI-2000 b and c are superb candidates for atmospheric characterization by the JWST, which can potentially distinguish whether they formed together or TOI-2000 c swept along material during migration to form TOI-2000 b.
AB - Hot jupiters (P < 10 d, M > 60 M?) are almost always found alone around their stars, but four out of hundreds known have inner companion planets. These rare companions allow us to constrain the hot jupiter's formation history by ruling out high-eccentricity tidal migration. Less is known about inner companions to hot Saturn-mass planets. We report here the discovery of the TOI-2000 system, which features a hot Saturn-mass planet with a smaller inner companion. The mini-neptune TOI-2000 b (2.70 ± 0.15 R?, 11.0 ± 2.4 M?) is in a 3.10-d orbit, and the hot saturn TOI-2000 c (R?, M?) is in a 9.13-d orbit. Both planets transit their host star TOI-2000 (TIC 371188886, V = 10.98, TESS magnitude = 10.36), a metal-rich ([Fe/H] = 0.439) G dwarf 173 pc away. TESS observed the two planets in sectors 9-11 and 36-38, and we followed up with ground-based photometry, spectroscopy, and speckle imaging. Radial velocities from CHIRON, FEROS, and HARPS allowed us to confirm both planets by direct mass measurement. In addition, we demonstrate constraining planetary and stellar parameters with MIST stellar evolutionary tracks through Hamiltonian Monte Carlo under the PyMC framework, achieving higher sampling efficiency and shorter run time compared to traditional Markov chain Monte Carlo. Having the brightest host star in the V band among similar systems, TOI-2000 b and c are superb candidates for atmospheric characterization by the JWST, which can potentially distinguish whether they formed together or TOI-2000 c swept along material during migration to form TOI-2000 b.
KW - planets and satellites: detection
KW - planets and satellites: formation
KW - planets and satellites: gaseous planets
KW - stars: individual: TOI-2000 (TIC 371188886)
KW - techniques: photometric
KW - techniques: radial velocities
UR - http://www.scopus.com/inward/record.url?scp=85163815148&partnerID=8YFLogxK
U2 - 10.1093/mnras/stad1666
DO - 10.1093/mnras/stad1666
M3 - Article
AN - SCOPUS:85163815148
SN - 0035-8711
VL - 524
SP - 1113
EP - 1138
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -