The K2-24 planetary system revisited by CHEOPS

V. Nascimbeni; L. Borsato; P. Leonardi; S. G. Sousa; T. G. Wilson; A. Fortier; A. Heitzmann; G. Mantovan; R. Luque; T. Zingales; G. Piotto; Y. Alibert; R. Alonso; T. Bárczy; D. Barrado Navascues; S. C. C. Barros; W. Baumjohann; T. Beck; W. Benz; N. Billot; F. Biondi; A. Brandeker; C. Broeg; M. -D. Busch; A. Collier Cameron; A. C. M. Correia; Sz Csizmadia; P. E. Cubillos; M. B. Davies; M. Deleuil; A. Deline; L. Delrez; O. D. S. Demangeon; B. -O. Demory; A. Derekas; B. Edwards; D. Ehrenreich; A. Erikson; L. Fossati; M. Fridlund; D. Gandolfi; K. Gazeas; M. Gillon; M. Güdel; M. N. Günther; Ch Helling; K. G. Isaak; F. Kerschbaum; L. L. Kiss; J. Korth; K. W. F. Lam; J. Laskar; A. Lecavelier des Etangs; A. Leleu; M. Lendl; D. Magrin; P. F. L. Maxted; B. Merín; C. Mordasini; G. Olofsson; R. Ottensamer; I. Pagano; E. Pallé; G. Peter; D. Pollacco; D. Queloz; R. Ragazzoni; N. Rando; H. Rauer; I. Ribas; N. C. Santos; G. Scandariato; D. Ségransan; A. E. Simon; A. M. S. Smith; R. Southworth; M. Stalport; S. Sulis; M. Gy Szabó; S. Udry; B. Ulmer; V. Van Grootel; J. Venturini; E. Villaver; N. A. Walton

doi:10.1051/0004-6361/202450852

The K2-24 planetary system revisited by CHEOPS

V. Nascimbeni, L. Borsato, P. Leonardi, S. G. Sousa, T. G. Wilson, A. Fortier, A. Heitzmann, G. Mantovan, R. Luque, T. Zingales, G. Piotto, Y. Alibert, R. Alonso, T. Bárczy, D. Barrado Navascues, S. C. C. Barros, W. Baumjohann, T. Beck, W. Benz, N. BillotF. Biondi, A. Brandeker, C. Broeg, M. -D. Busch, A. Collier Cameron, A. C. M. Correia, Sz Csizmadia, P. E. Cubillos, M. B. Davies, M. Deleuil, A. Deline, L. Delrez, O. D. S. Demangeon, B. -O. Demory, A. Derekas, B. Edwards, D. Ehrenreich, A. Erikson, L. Fossati, M. Fridlund, D. Gandolfi, K. Gazeas, M. Gillon, M. Güdel, M. N. Günther, Ch Helling, K. G. Isaak, F. Kerschbaum, L. L. Kiss, J. Korth, K. W. F. Lam, J. Laskar, A. Lecavelier des Etangs, A. Leleu, M. Lendl, D. Magrin, P. F. L. Maxted, B. Merín, C. Mordasini, G. Olofsson, R. Ottensamer, I. Pagano, E. Pallé, G. Peter, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, H. Rauer, I. Ribas, N. C. Santos, G. Scandariato, D. Ségransan, A. E. Simon, A. M. S. Smith, R. Southworth, M. Stalport, S. Sulis, M. Gy Szabó, S. Udry, B. Ulmer, V. Van Grootel, J. Venturini, E. Villaver, N. A. Walton

Research output: Contribution to journal › Article › peer-review

Abstract

The planetary system K2-24 is composed of two transiting low-density Neptunians locked in an almost perfect 2:1 resonance and showing large transit time variations (TTVs), and it is an excellent laboratory to search for signatures of planetary migration. Previous studies performed with K2, Spitzer, and RV data tentatively claimed a significant non-zero eccentricity for one or both planets, possibly high enough to challenge the scenario of pure disk migration through resonant capture. With 13 new CHEOPS light curves (seven of planet b, six of planet c), we carried out a global photometric and dynamical re-analysis by including all the available literature data as well. We obtained the most accurate set of planetary parameters to date for the K2-24 system, including radii and masses at 1% and 5% precision (now essentially limited by the uncertainty on stellar parameters) and non-zero eccentricities eb = 0.0498−0.0018+0.0011, ec = 0.0282−0.0007+0.0003 detected at very high significance for both planets. Such relatively large values imply the need for an additional physical mechanism of eccentricity excitation during or after the migration stage. Also, while the accuracy of the previous TTV model had drifted by up to 0.5 days at the current time, we constrained the orbital solution firmly enough to predict the forthcoming transits for the next ~15 years, thus enabling efficient follow-up with top-level facilities such as JWST or ESPRESSO.

Original language	English
Article number	A349
Number of pages	16
Journal	Astronomy & Astrophysics
Volume	690
Early online date	22 Oct 2024
DOIs	https://doi.org/10.1051/0004-6361/202450852
Publication status	Published - Oct 2024

Keywords

Techniques: photometric
Techniques: spectroscopic
Planets and satellites: detection
Planets and satellites: dynamical evolution and stability
Planets and satellites: gaseous planets

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https://www.arxiv.org/abs/2409.02995Licence: CC BY-SA

Cite this

Nascimbeni, V., Borsato, L., Leonardi, P., Sousa, S. G., Wilson, T. G., Fortier, A., Heitzmann, A., Mantovan, G., Luque, R., Zingales, T., Piotto, G., Alibert, Y., Alonso, R., Bárczy, T., Barrado Navascues, D., Barros, S. C. C., Baumjohann, W., Beck, T., Benz, W., ... Walton, N. A. (2024). The K2-24 planetary system revisited by CHEOPS. Astronomy & Astrophysics, 690, Article A349. https://doi.org/10.1051/0004-6361/202450852

@article{63813f4d682541cc9b960959e5db3616,

title = "The K2-24 planetary system revisited by CHEOPS",

abstract = "The planetary system K2-24 is composed of two transiting low-density Neptunians locked in an almost perfect 2:1 resonance and showing large transit time variations (TTVs), and it is an excellent laboratory to search for signatures of planetary migration. Previous studies performed with K2, Spitzer, and RV data tentatively claimed a significant non-zero eccentricity for one or both planets, possibly high enough to challenge the scenario of pure disk migration through resonant capture. With 13 new CHEOPS light curves (seven of planet b, six of planet c), we carried out a global photometric and dynamical re-analysis by including all the available literature data as well. We obtained the most accurate set of planetary parameters to date for the K2-24 system, including radii and masses at 1\% and 5\% precision (now essentially limited by the uncertainty on stellar parameters) and non-zero eccentricities eb = 0.0498−0.0018+0.0011, ec = 0.0282−0.0007+0.0003 detected at very high significance for both planets. Such relatively large values imply the need for an additional physical mechanism of eccentricity excitation during or after the migration stage. Also, while the accuracy of the previous TTV model had drifted by up to 0.5 days at the current time, we constrained the orbital solution firmly enough to predict the forthcoming transits for the next \textasciitilde{}15 years, thus enabling efficient follow-up with top-level facilities such as JWST or ESPRESSO.",

keywords = "Techniques: photometric, Techniques: spectroscopic, Planets and satellites: detection, Planets and satellites: dynamical evolution and stability, Planets and satellites: gaseous planets",

author = "V. Nascimbeni and L. Borsato and P. Leonardi and Sousa, \{S. G.\} and Wilson, \{T. G.\} and A. Fortier and A. Heitzmann and G. Mantovan and R. Luque and T. Zingales and G. Piotto and Y. Alibert and R. Alonso and T. B{\'a}rczy and \{Barrado Navascues\}, D. and Barros, \{S. C. C.\} and W. Baumjohann and T. Beck and W. Benz and N. Billot and F. Biondi and A. Brandeker and C. Broeg and Busch, \{M. -D.\} and Cameron, \{A. Collier\} and Correia, \{A. C. M.\} and Sz Csizmadia and Cubillos, \{P. E.\} and Davies, \{M. B.\} and M. Deleuil and A. Deline and L. Delrez and Demangeon, \{O. D. S.\} and Demory, \{B. -O.\} and A. Derekas and B. Edwards and D. Ehrenreich and A. Erikson and L. Fossati and M. Fridlund and D. Gandolfi and K. Gazeas and M. Gillon and M. G{\"u}del and G{\"u}nther, \{M. N.\} and Ch Helling and Isaak, \{K. G.\} and F. Kerschbaum and Kiss, \{L. L.\} and J. Korth and Lam, \{K. W. F.\} and J. Laskar and \{Lecavelier des Etangs\}, A. and A. Leleu and M. Lendl and D. Magrin and Maxted, \{P. F. L.\} and B. Mer{\'i}n and C. Mordasini and G. Olofsson and R. Ottensamer and I. Pagano and E. Pall{\'e} and G. Peter and D. Pollacco and D. Queloz and R. Ragazzoni and N. Rando and H. Rauer and I. Ribas and Santos, \{N. C.\} and G. Scandariato and D. S{\'e}gransan and Simon, \{A. E.\} and Smith, \{A. M. S.\} and R. Southworth and M. Stalport and S. Sulis and Szab{\'o}, \{M. Gy\} and S. Udry and B. Ulmer and \{Van Grootel\}, V. and J. Venturini and E. Villaver and Walton, \{N. A.\}",

note = "Funding: ACC acknowledges support from STFC consolidated grant number ST/V000861/1, and UKSA grant number ST/X002217/1. TWi acknowledges support from the UKSA and the University of Warwick. CHe acknowledges support from the European Union H2020-MSCA-ITN-2019 under Grant Agreement no. 860470 (CHAMELEON). PM acknowledges support from STFC research grant number ST/R000638/1. NCSa acknowledges funding by the European Union (ERC, FIERCE, 101052347). NAW acknowledges UKSA grant ST/R004838/1.",

year = "2024",

month = oct,

doi = "10.1051/0004-6361/202450852",

language = "English",

volume = "690",

journal = "Astronomy \& Astrophysics",

issn = "0004-6361",

publisher = "EDP Sciences",

}

Nascimbeni, V, Borsato, L, Leonardi, P, Sousa, SG, Wilson, TG, Fortier, A, Heitzmann, A, Mantovan, G, Luque, R, Zingales, T, Piotto, G, Alibert, Y, Alonso, R, Bárczy, T, Barrado Navascues, D, Barros, SCC, Baumjohann, W, Beck, T, Benz, W, Billot, N, Biondi, F, Brandeker, A, Broeg, C, Busch, M-D, Cameron, AC, Correia, ACM, Csizmadia, S, Cubillos, PE, Davies, MB, Deleuil, M, Deline, A, Delrez, L, Demangeon, ODS, Demory, B-O, Derekas, A, Edwards, B, Ehrenreich, D, Erikson, A, Fossati, L, Fridlund, M, Gandolfi, D, Gazeas, K, Gillon, M, Güdel, M, Günther, MN, Helling, C, Isaak, KG, Kerschbaum, F, Kiss, LL, Korth, J, Lam, KWF, Laskar, J, Lecavelier des Etangs, A, Leleu, A, Lendl, M, Magrin, D, Maxted, PFL, Merín, B, Mordasini, C, Olofsson, G, Ottensamer, R, Pagano, I, Pallé, E, Peter, G, Pollacco, D, Queloz, D, Ragazzoni, R, Rando, N, Rauer, H, Ribas, I, Santos, NC, Scandariato, G, Ségransan, D, Simon, AE, Smith, AMS, Southworth, R, Stalport, M, Sulis, S, Szabó, MG, Udry, S, Ulmer, B, Van Grootel, V, Venturini, J, Villaver, E & Walton, NA 2024, 'The K2-24 planetary system revisited by CHEOPS', Astronomy & Astrophysics, vol. 690, A349. https://doi.org/10.1051/0004-6361/202450852

TY - JOUR

T1 - The K2-24 planetary system revisited by CHEOPS

AU - Nascimbeni, V.

AU - Borsato, L.

AU - Leonardi, P.

AU - Sousa, S. G.

AU - Wilson, T. G.

AU - Fortier, A.

AU - Heitzmann, A.

AU - Mantovan, G.

AU - Luque, R.

AU - Zingales, T.

AU - Piotto, G.

AU - Alibert, Y.

AU - Alonso, R.

AU - Bárczy, T.

AU - Barrado Navascues, D.

AU - Barros, S. C. C.

AU - Baumjohann, W.

AU - Beck, T.

AU - Benz, W.

AU - Billot, N.

AU - Biondi, F.

AU - Brandeker, A.

AU - Broeg, C.

AU - Busch, M. -D.

AU - Cameron, A. Collier

AU - Correia, A. C. M.

AU - Csizmadia, Sz

AU - Cubillos, P. E.

AU - Davies, M. B.

AU - Deleuil, M.

AU - Deline, A.

AU - Delrez, L.

AU - Demangeon, O. D. S.

AU - Demory, B. -O.

AU - Derekas, A.

AU - Edwards, B.

AU - Ehrenreich, D.

AU - Erikson, A.

AU - Fossati, L.

AU - Fridlund, M.

AU - Gandolfi, D.

AU - Gazeas, K.

AU - Gillon, M.

AU - Güdel, M.

AU - Günther, M. N.

AU - Helling, Ch

AU - Isaak, K. G.

AU - Kerschbaum, F.

AU - Kiss, L. L.

AU - Korth, J.

AU - Lam, K. W. F.

AU - Laskar, J.

AU - Lecavelier des Etangs, A.

AU - Leleu, A.

AU - Lendl, M.

AU - Magrin, D.

AU - Maxted, P. F. L.

AU - Merín, B.

AU - Mordasini, C.

AU - Olofsson, G.

AU - Ottensamer, R.

AU - Pagano, I.

AU - Pallé, E.

AU - Peter, G.

AU - Pollacco, D.

AU - Queloz, D.

AU - Ragazzoni, R.

AU - Rando, N.

AU - Rauer, H.

AU - Ribas, I.

AU - Santos, N. C.

AU - Scandariato, G.

AU - Ségransan, D.

AU - Simon, A. E.

AU - Smith, A. M. S.

AU - Southworth, R.

AU - Stalport, M.

AU - Sulis, S.

AU - Szabó, M. Gy

AU - Udry, S.

AU - Ulmer, B.

AU - Van Grootel, V.

AU - Venturini, J.

AU - Villaver, E.

AU - Walton, N. A.

N1 - Funding: ACC acknowledges support from STFC consolidated grant number ST/V000861/1, and UKSA grant number ST/X002217/1. TWi acknowledges support from the UKSA and the University of Warwick. CHe acknowledges support from the European Union H2020-MSCA-ITN-2019 under Grant Agreement no. 860470 (CHAMELEON). PM acknowledges support from STFC research grant number ST/R000638/1. NCSa acknowledges funding by the European Union (ERC, FIERCE, 101052347). NAW acknowledges UKSA grant ST/R004838/1.

PY - 2024/10

Y1 - 2024/10

N2 - The planetary system K2-24 is composed of two transiting low-density Neptunians locked in an almost perfect 2:1 resonance and showing large transit time variations (TTVs), and it is an excellent laboratory to search for signatures of planetary migration. Previous studies performed with K2, Spitzer, and RV data tentatively claimed a significant non-zero eccentricity for one or both planets, possibly high enough to challenge the scenario of pure disk migration through resonant capture. With 13 new CHEOPS light curves (seven of planet b, six of planet c), we carried out a global photometric and dynamical re-analysis by including all the available literature data as well. We obtained the most accurate set of planetary parameters to date for the K2-24 system, including radii and masses at 1% and 5% precision (now essentially limited by the uncertainty on stellar parameters) and non-zero eccentricities eb = 0.0498−0.0018+0.0011, ec = 0.0282−0.0007+0.0003 detected at very high significance for both planets. Such relatively large values imply the need for an additional physical mechanism of eccentricity excitation during or after the migration stage. Also, while the accuracy of the previous TTV model had drifted by up to 0.5 days at the current time, we constrained the orbital solution firmly enough to predict the forthcoming transits for the next ~15 years, thus enabling efficient follow-up with top-level facilities such as JWST or ESPRESSO.

AB - The planetary system K2-24 is composed of two transiting low-density Neptunians locked in an almost perfect 2:1 resonance and showing large transit time variations (TTVs), and it is an excellent laboratory to search for signatures of planetary migration. Previous studies performed with K2, Spitzer, and RV data tentatively claimed a significant non-zero eccentricity for one or both planets, possibly high enough to challenge the scenario of pure disk migration through resonant capture. With 13 new CHEOPS light curves (seven of planet b, six of planet c), we carried out a global photometric and dynamical re-analysis by including all the available literature data as well. We obtained the most accurate set of planetary parameters to date for the K2-24 system, including radii and masses at 1% and 5% precision (now essentially limited by the uncertainty on stellar parameters) and non-zero eccentricities eb = 0.0498−0.0018+0.0011, ec = 0.0282−0.0007+0.0003 detected at very high significance for both planets. Such relatively large values imply the need for an additional physical mechanism of eccentricity excitation during or after the migration stage. Also, while the accuracy of the previous TTV model had drifted by up to 0.5 days at the current time, we constrained the orbital solution firmly enough to predict the forthcoming transits for the next ~15 years, thus enabling efficient follow-up with top-level facilities such as JWST or ESPRESSO.

KW - Techniques: photometric

KW - Techniques: spectroscopic

KW - Planets and satellites: detection

KW - Planets and satellites: dynamical evolution and stability

KW - Planets and satellites: gaseous planets

UR - https://www.scopus.com/pages/publications/85207399984

U2 - 10.1051/0004-6361/202450852

DO - 10.1051/0004-6361/202450852

M3 - Article

SN - 0004-6361

VL - 690

JO - Astronomy & Astrophysics

JF - Astronomy & Astrophysics

M1 - A349

ER -

The K2-24 planetary system revisited by CHEOPS

Abstract

Keywords

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