New Mass and Radius Constraints on the LHS 1140 Planets: LHS 1140 b Is either a Temperate Mini-Neptune or a Water World

被引：15

作者：

Cadieux, Charles ^{[1
]}

Plotnykov, Mykhaylo ^{[2
]}

Doyon, Rene ^{[1
,3
]}

Valencia, Diana ^{[4
,5
]}

Jahandar, Farbod ^{[1
]}

Dang, Lisa ^{[1
]}

Turbet, Martin ^{[6
,7
]}

Fauchez, Thomas J. ^{[8
,9
,10
]}

Cloutier, Ryan ^{[11
]}

Cherubim, Collin ^{[12
,13
]}

Artigau, Etienne ^{[1
,3
]}

Cook, Neil J. ^{[1
]}

Edwards, Billy ^{[14
,15
]}

Hallatt, Tim ^{[1
,16
,17
]}

Charnay, Benjamin ^{[18
]}

Bouchy, Francois ^{[19
]}

Allart, Romain ^{[1
]}

Mignon, Lucile ^{[19
]}

Baron, Frederique ^{[1
]}

Barros, Susana C. C. ^{[20
,21
]}

Benneke, Bjorn ^{[1
]}

Canto Martins, B. L. ^{[22
]}

Cowan, Nicolas B. ^{[16
,17
,23
]}

De Medeiros, J. R. ^{[22
]}

Delfosse, Xavier ^{[24
]}

Delgado-Mena, Elisa ^{[20
]}

Dumusque, Xavier ^{[19
]}

Ehrenreich, David ^{[19
]}

Frensch, Yolanda G. C. ^{[19
]}

Gonzalez Hernandez, J. I. ^{[25
,26
]}

Hara, Nathan C. ^{[19
]}

Lafreniere, David ^{[1
]}

Lo Curto, Gaspare ^{[27
]}

Malo, Lison ^{[1
,3
]}

Melo, Claudio ^{[27
]}

Mounzer, Dany ^{[19
]}

Passeger, Vera Maria ^{[25
,26
,28
]}

Pepe, Francesco ^{[19
]}

Poulin-Girard, Anne-Sophie ^{[29
]}

Santos, Nuno C. ^{[20
,21
]}

Sosnowska, Danuta ^{[19
]}

Suarez Mascareno, Alejandro ^{[25
,26
]}

Thibault, Simon ^{[30
]}

Vaulato, Valentina ^{[19
]}

Wade, Gregg A. ^{[31
]}

Wildi, Francois ^{[19
]}

机构：

[1] Univ Montreal, Inst Trottier Rech Exoplanetes, 1375 Ave Therese Lavoie Roux, Montreal, PQ H2V 0B3, Canada

[2] Univ Toronto, Dept Phys, Toronto, ON M5S 3H4, Canada

[3] Univ Montreal, Observ Mt Megant, Montreal, PQ H3C 3J7, Canada

[4] Univ Toronto Scarborough, Dept Phys & Environm Sci, Scarborough, ON M1C 1A4, Canada

[5] Univ Toronto, David A Dunlap Dept Astron & Astrophys, 50 St George St, Toronto, ON M5S 3H4, Canada

[6] PSL Res Univ, Sorbonne Univ, Ecole Normale Super, Lab Meteorol Dynam,IPSL,CNRS,Ecole Polytech, F-75005 Paris, France

[7] Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France

[8] NASA, Goddard Space Flight Ctr, 8800 Greenbelt Rd, Greenbelt, MD 20771 USA

[9] Amer Univ, Dept Phys, Integrated Space Sci & Technol Inst, Washington, DC 20016 USA

[10] NASA GSFC Sellers Exoplanet Environments Collabor, 8800 Greenbelt Rd, Greenbelt, MD 20771 USA

[11] McMaster Univ, Dept Phys & Astron, 1280 Main St West, Hamilton, ON L8S 4L8, Canada

[12] Harvard Univ, Earth & Planetary Sci, 20 Oxford St, Cambridge, MA 02138 USA

[13] Ctr Astrophys Harvard & Smithsonian, 60 Garden St, Cambridge, MA 02138 USA

[14] SRON Netherlands Inst Space Res, SRON, Niels Bohrweg 4, NL-2333 CA Leiden, Netherlands

[15] UCL, Dept Phys & Astron, London, England

[16] McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada

[17] McGill Univ, Trottier Space Inst, Montreal, PQ H3A 2T8, Canada

[18] Univ Paris Cite, Sorbonne Univ, Univ PSL, LESIA,Observ Paris,CNRS, 5 Pl Jules Janssen, F-92195 Meudon, France

[19] Univ Geneva, Dept Astron, Chemin Pegasi 51, CH-1290 Versoix, Switzerland

[20] Univ Porto, CAUP, Inst Astrofis & Ciencias Espaco, Rua Estrelas, PT-4150762 Porto, Portugal

[21] Univ Porto, Fac Ciencias, Dept Fis & Astron, Rua Campo Alegre, P-4169007 Porto, Portugal

[22] Univ Fed Rio Grande do Norte, Dept Fis Teor & Expt, Campus Univ, BR-59072970 Natal, RN, Brazil

[23] McGill Univ, Dept Earth & Planetary Sci, 3450 Rue Univ, Montreal, PQ H3A 0E8, Canada

[24] Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France

[25] Inst Astrofis Canarias, E-38205 Tenerife, Spain

[26] Univ La Laguna, Dept Astrofis, E-38206 Tenerife, Spain

[27] European Southern Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany

[28] Hamburger Sternwarte, Gojenbergsweg 112, D-21029 Hamburg, Germany

[29] ABB, Quebec City, PQ G1P 0B2, Canada

[30] Univ Laval, Ctr Opt Photon & Lasers, Laval, PQ G1V 0A6, Canada

[31] Royal Mil Coll Canada, Dept Phys & Space Sci, POB 17000, Kingston, ON, Canada

来源：

ASTROPHYSICAL JOURNAL LETTERS | 2024年 / 960卷 / 01期

基金：

加拿大自然科学与工程研究理事会; 欧洲研究理事会; 瑞士国家科学基金会;

关键词：

LIMB-DARKENING COEFFICIENTS; M DWARF; SUPER-EARTH; HABITABLE-ZONE; ERROR-CORRECTION; TERRESTRIAL; EXOPLANET; KEPLER; EVOLUTION; ROCKY;

D O I：

10.3847/2041-8213/ad1691

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The two-planet transiting system LHS 1140 has been extensively observed since its discovery in 2017, notably with Spitzer, HST, TESS, and ESPRESSO, placing strong constraints on the parameters of the M4.5 host star and its small temperate exoplanets, LHS 1140 b and c. Here, we reanalyze the ESPRESSO observations of LHS 1140 with the novel line-by-line framework designed to fully exploit the radial velocity content of a stellar spectrum while being resilient to outlier measurements. The improved radial velocities, combined with updated stellar parameters, consolidate our knowledge of the mass of LHS 1140 b (5.60 +/- 0.19 M circle plus) and LHS 1140 c (1.91 +/- 0.06 M circle plus) with an unprecedented precision of 3%. Transits from Spitzer, HST, and TESS are jointly analyzed for the first time, allowing us to refine the planetary radii of b (1.730 +/- 0.025 R circle plus) and c (1.272 +/- 0.026 R circle plus). Stellar abundance measurements of refractory elements (Fe, Mg, and Si) obtained with NIRPS are used to constrain the internal structure of LHS 1140 b. This planet is unlikely to be a rocky super-Earth, as previously reported, but rather a mini-Neptune with a similar to 0.1% H/He envelope by mass or a water world with a water-mass fraction between 9% and 19%, depending on the atmospheric composition and relative abundance of Fe and Mg. While the mini-Neptune case would not be habitable, a water-abundant LHS 1140 b potentially has habitable surface conditions according to 3D global climate models, suggesting liquid water at the substellar point for atmospheres with relatively low CO2 concentration, from Earth-like to a few bars.

引用

页数：24