It Takes Two Planets in Resonance to Tango around K2-146
(2020) In Astronomical Journal 159(3).- Abstract
K2-146 is a cool, 0.358M⊙ dwarf that was found to host a mini-Neptune with a 2.67 day period. The planet exhibited strong transit timing variations (TTVs) of greater than 30 minutes, indicative of the presence of an additional object in the system. Here we report the discovery of the previously undetected outer planet in the system, K2-146 c, using additional photometric data. K2-146 c was found to have a grazing transit geometry and a 3.97 day period. The outer planet was only significantly detected in the latter K2 campaigns presumably because of precession of its orbital plane. The TTVs of K2-146 b and c were measured using observations spanning a baseline of almost 1200 days. We found strong anti-correlation in the TTVs, suggesting... (More)
K2-146 is a cool, 0.358M⊙ dwarf that was found to host a mini-Neptune with a 2.67 day period. The planet exhibited strong transit timing variations (TTVs) of greater than 30 minutes, indicative of the presence of an additional object in the system. Here we report the discovery of the previously undetected outer planet in the system, K2-146 c, using additional photometric data. K2-146 c was found to have a grazing transit geometry and a 3.97 day period. The outer planet was only significantly detected in the latter K2 campaigns presumably because of precession of its orbital plane. The TTVs of K2-146 b and c were measured using observations spanning a baseline of almost 1200 days. We found strong anti-correlation in the TTVs, suggesting the two planets are gravitationally interacting. Our TTV and transit model analyses revealed that K2-146 b has a radius of 2.25 ± 0.10 R⊕ and a mass of 5.6 ± 0.7 M⊕, whereas K2-146 c has a radius of 2.59-0.39+1.81 R⊕ and a mass of 7.1 ± 0.9 M⊕. The inner and outer planets likely have moderate eccentricities of e = 0.14 ± 0.07 and 0.16 ± 0.07, respectively. Long-term numerical integrations of the two-planet orbital solution show that it can be dynamically stable for at least 2 Myr. We show that the resonance angles of the planet pair are librating, which may be an indication that K2-146 b and c are in a 3:2 mean motion resonance. The orbital architecture of the system points to a possible convergent migration origin.
(Less)
- author
- publishing date
- 2020-03
- type
- Contribution to journal
- publication status
- published
- in
- Astronomical Journal
- volume
- 159
- issue
- 3
- article number
- 120
- publisher
- IOP Publishing
- external identifiers
-
- scopus:85088709041
- ISSN
- 0004-6256
- DOI
- 10.3847/1538-3881/ab66c9
- language
- English
- LU publication?
- no
- additional info
- Funding Information: 2020-03-01 2020-02-24 15:14:32 cgi/release: Article released bin/incoming: New from .zip DFG Schwerpunkt RA714/14-1 DFG Schwerpunkt PA525/18-1 DFG Schwerpunkt PA525/19-1 DFG Schwerpunkt PA525/20-1 DFG Schwerpunkt HA3279/12-1 Swedish National Space Agency DNR 163/16 Swedish National Space Agency DNR 174/18 JSPS KAKENHI JP18H01265 JSPS KAKENHI JP18H05439 JST PRESTO JPMJPR1775 UK Science and Technology Facilities Council (STFC) ST/S000488/1 UK Science and Technology Facilities Council (STFC) ST/R004846/1 Spanish Ministry - Ramon y Cajal fellowship RYC-2015-17697 GACR 17-01752J yes Publisher Copyright: © 2020. The American Astronomical Society. All rights reserved..
- id
- 7d759049-a482-4576-b837-b9be2911a3d7
- date added to LUP
- 2023-02-02 09:25:58
- date last changed
- 2023-02-21 10:43:20
@article{7d759049-a482-4576-b837-b9be2911a3d7,
abstract = {{<p>K2-146 is a cool, 0.358M⊙ dwarf that was found to host a mini-Neptune with a 2.67 day period. The planet exhibited strong transit timing variations (TTVs) of greater than 30 minutes, indicative of the presence of an additional object in the system. Here we report the discovery of the previously undetected outer planet in the system, K2-146 c, using additional photometric data. K2-146 c was found to have a grazing transit geometry and a 3.97 day period. The outer planet was only significantly detected in the latter K2 campaigns presumably because of precession of its orbital plane. The TTVs of K2-146 b and c were measured using observations spanning a baseline of almost 1200 days. We found strong anti-correlation in the TTVs, suggesting the two planets are gravitationally interacting. Our TTV and transit model analyses revealed that K2-146 b has a radius of 2.25 ± 0.10 R⊕ and a mass of 5.6 ± 0.7 M⊕, whereas K2-146 c has a radius of 2.59<sub>-0.39</sub><sup>+1.81</sup> R⊕ and a mass of 7.1 ± 0.9 M⊕. The inner and outer planets likely have moderate eccentricities of e = 0.14 ± 0.07 and 0.16 ± 0.07, respectively. Long-term numerical integrations of the two-planet orbital solution show that it can be dynamically stable for at least 2 Myr. We show that the resonance angles of the planet pair are librating, which may be an indication that K2-146 b and c are in a 3:2 mean motion resonance. The orbital architecture of the system points to a possible convergent migration origin.</p>}},
author = {{Lam, Kristine W.F. and Korth, Judith and Masuda, Kento and Csizmadia, Szilárd and Eigmüller, Philipp and Stefánsson, Gumundur Kári and Endl, Michael and Albrecht, Simon and Robertson, Paul and Luque, Rafael and Livingston, John H. and Hirano, Teruyuki and Sobrino, Roi Alonso and Barragán, Oscar and Cabrera, Juan and Carleo, Ilaria and Chaushev, Alexander and Cochran, William D. and Dai, Fei and Leon, Jerome de and Deeg, Hans J. and Erikson, Anders and Esposito, Massimiliano and Fridlund, Malcolm and Fukui, Akihiko and Gandolfi, Davide and Georgieva, Iskra and Cuesta, Lucá Gonzalez and Grziwa, Sascha and Guenther, Eike W. and Hatzes, Artie P. and Hidalgo, Diego and Hjorth, Maria and Kabath, Petr and Knudstrup, Emil and Lund, Mikkel N. and Mahadevan, Suvrath and Mathur, Savita and Rodríguez, Pilar Montantildes and Murgas, Felipe and Narita, Norio and Nespral, David and Niraula, Prajwal and Palle, Enric and P tzold, Martin and Persson, Carina M. and Prieto-Arranz, Jorge and Rauer, Heike and Redfield, Seth and Ribas, Ignasi and Skarka, Marek and Smith, Alexis M.S. and Subjak, Jan and Eylen, Vincent Van}},
issn = {{0004-6256}},
language = {{eng}},
number = {{3}},
publisher = {{IOP Publishing}},
series = {{Astronomical Journal}},
title = {{It Takes Two Planets in Resonance to Tango around K2-146}},
url = {{http://dx.doi.org/10.3847/1538-3881/ab66c9}},
doi = {{10.3847/1538-3881/ab66c9}},
volume = {{159}},
year = {{2020}},
}