A new mass and radius determination of the ultra-short period planet K2-106b and the fluffy planet K2-106c

E W Guenther; E Goffo; D Sebastian; A M S Smith; C M Persson; M. Fridlund; D. Gandolfi; J Korth

doi:10.1093/mnras/stae494

A new mass and radius determination of the ultra-short period planet K2-106b and the fluffy planet K2-106c

E W Guenther^*, E Goffo, D Sebastian, A M S Smith, C M Persson, M. Fridlund, D. Gandolfi, J Korth

^*Corresponding author for this work

Physics and Astronomy

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

2 Downloads (Pure)

Abstract

Ultra-short period planets have orbital periods of less than one day. Since their masses and radii can be determined to a higher precision than long-period planets, they are the preferred targets to determine the density of planets which constrains their composition. The K2-106 system is particularly interesting because it contains two planets of nearly identical masses. One is a high density USP, the other is a low-density planet that has an orbital period of 13 days. Combining the Gaia DR3 results with new ESPRESSO data allows us to determine the masses and radii of the two planets more precisely than before. We find that the USP K2-106b has a density consistent with an Earth-like composition, and K2-106c is a low-density planet that presumably has an extended atmosphere. We measure a radius of R_p= 1.676_-0.037^+0.037R_⊕, a mass of M_p= 7.80_-0.70^+0.71 M_⊕ and a density of ρ = 9.09_-0.98^+0.98 gcm^-3for K2-106b. For K2-106c, we derive R_p= 2.84_-0.08^+0.10 R_⊕, M_p = 7.3_-2.4^+2.5 M_⊕, and a density of ρ = 1.72_-0.58^+0.66 gcm^-3. We finally discuss the possible structures of the two planets with respect to other low-mass planets.

Original language	English
Journal	Monthly Notices of the Royal Astronomical Society
Early online date	21 Feb 2024
DOIs	https://doi.org/10.1093/mnras/stae494
Publication status	E-pub ahead of print - 21 Feb 2024

Bibliographical note

Acknowledgments:
This work was generously supported by the Deutsche Forschungsgemeinschaft (DFG) in the framework of the priority programme “Exploring the Diversity of Extrasolar Planets” (SPP 1992) in program GU 464/22, and by the Thuringer Ministerium fur Wirtschaft, Wissenschaft und Digitale Gesellschaft.

E. G. acknowledges the generous support from the Deutsche Forschungsgemeinschaft (DFG) of the grant HA3279/14-1.

J. K. gratefully acknowledges the support of the Swedish National Space Agency (SNSA; DNR 2020-00104) and of the Swedish Research Council (VR; Etableringsbidrag 2017-04945).

This research is also supported work funded from the European Research Council (ERC) the European Union’s Horizon 2020 research and innovation programme (grant agreement n◦803193/BEBOP).

Keywords

planetary systems
planets and satellites: composition
planets and satellites: fundamental parameters
planets and satellites: individual K2-106b and K2-106c
stars: fundamental parameters
stars: late-type

Access to Document

10.1093/mnras/stae494Licence: Creative Commons: Attribution (CC BY)

GuentherE2024NewAccepted author manuscript, 2.36 MBLicence: Creative Commons: Attribution (CC BY)

H2020_ERC_BEBOP
Triaud, A.
European Commission
1/11/18 → 31/10/24
Project: EU

Cite this

@article{64498e46e215450b91e336452900b4df,

title = "A new mass and radius determination of the ultra-short period planet K2-106b and the fluffy planet K2-106c",

abstract = "Ultra-short period planets have orbital periods of less than one day. Since their masses and radii can be determined to a higher precision than long-period planets, they are the preferred targets to determine the density of planets which constrains their composition. The K2-106 system is particularly interesting because it contains two planets of nearly identical masses. One is a high density USP, the other is a low-density planet that has an orbital period of 13 days. Combining the Gaia DR3 results with new ESPRESSO data allows us to determine the masses and radii of the two planets more precisely than before. We find that the USP K2-106b has a density consistent with an Earth-like composition, and K2-106c is a low-density planet that presumably has an extended atmosphere. We measure a radius of Rp = 1.676-0.037+0.037 R⊕, a mass of Mp = 7.80-0.70+0.71 M⊕ and a density of ρ = 9.09-0.98+0.98 gcm-3 for K2-106b. For K2-106c, we derive Rp = 2.84-0.08+0.10 R⊕, Mp = 7.3-2.4+2.5 M⊕, and a density of ρ = 1.72-0.58+0.66 gcm-3. We finally discuss the possible structures of the two planets with respect to other low-mass planets. ",

keywords = "planetary systems, planets and satellites: composition, planets and satellites: fundamental parameters, planets and satellites: individual K2-106b and K2-106c, stars: fundamental parameters, stars: late-type",

author = "Guenther, {E W} and E Goffo and D Sebastian and Smith, {A M S} and Persson, {C M} and M. Fridlund and D. Gandolfi and J Korth",

note = "Acknowledgments: This work was generously supported by the Deutsche Forschungsgemeinschaft (DFG) in the framework of the priority programme “Exploring the Diversity of Extrasolar Planets” (SPP 1992) in program GU 464/22, and by the Thuringer Ministerium fur Wirtschaft, Wissenschaft und Digitale Gesellschaft. E. G. acknowledges the generous support from the Deutsche Forschungsgemeinschaft (DFG) of the grant HA3279/14-1. J. K. gratefully acknowledges the support of the Swedish National Space Agency (SNSA; DNR 2020-00104) and of the Swedish Research Council (VR; Etableringsbidrag 2017-04945). This research is also supported work funded from the European Research Council (ERC) the European Union{\textquoteright}s Horizon 2020 research and innovation programme (grant agreement n◦803193/BEBOP). ",

year = "2024",

month = feb,

day = "21",

doi = "10.1093/mnras/stae494",

language = "English",

journal = "Monthly Notices of the Royal Astronomical Society",

issn = "0035-8711",

publisher = "SIPRI/Oxford University Press",

}

TY - JOUR

T1 - A new mass and radius determination of the ultra-short period planet K2-106b and the fluffy planet K2-106c

AU - Guenther, E W

AU - Goffo, E

AU - Sebastian, D

AU - Smith, A M S

AU - Persson, C M

AU - Fridlund, M.

AU - Gandolfi, D.

AU - Korth, J

N1 - Acknowledgments: This work was generously supported by the Deutsche Forschungsgemeinschaft (DFG) in the framework of the priority programme “Exploring the Diversity of Extrasolar Planets” (SPP 1992) in program GU 464/22, and by the Thuringer Ministerium fur Wirtschaft, Wissenschaft und Digitale Gesellschaft. E. G. acknowledges the generous support from the Deutsche Forschungsgemeinschaft (DFG) of the grant HA3279/14-1. J. K. gratefully acknowledges the support of the Swedish National Space Agency (SNSA; DNR 2020-00104) and of the Swedish Research Council (VR; Etableringsbidrag 2017-04945). This research is also supported work funded from the European Research Council (ERC) the European Union’s Horizon 2020 research and innovation programme (grant agreement n◦803193/BEBOP).

PY - 2024/2/21

Y1 - 2024/2/21

N2 - Ultra-short period planets have orbital periods of less than one day. Since their masses and radii can be determined to a higher precision than long-period planets, they are the preferred targets to determine the density of planets which constrains their composition. The K2-106 system is particularly interesting because it contains two planets of nearly identical masses. One is a high density USP, the other is a low-density planet that has an orbital period of 13 days. Combining the Gaia DR3 results with new ESPRESSO data allows us to determine the masses and radii of the two planets more precisely than before. We find that the USP K2-106b has a density consistent with an Earth-like composition, and K2-106c is a low-density planet that presumably has an extended atmosphere. We measure a radius of Rp = 1.676-0.037+0.037 R⊕, a mass of Mp = 7.80-0.70+0.71 M⊕ and a density of ρ = 9.09-0.98+0.98 gcm-3 for K2-106b. For K2-106c, we derive Rp = 2.84-0.08+0.10 R⊕, Mp = 7.3-2.4+2.5 M⊕, and a density of ρ = 1.72-0.58+0.66 gcm-3. We finally discuss the possible structures of the two planets with respect to other low-mass planets.

AB - Ultra-short period planets have orbital periods of less than one day. Since their masses and radii can be determined to a higher precision than long-period planets, they are the preferred targets to determine the density of planets which constrains their composition. The K2-106 system is particularly interesting because it contains two planets of nearly identical masses. One is a high density USP, the other is a low-density planet that has an orbital period of 13 days. Combining the Gaia DR3 results with new ESPRESSO data allows us to determine the masses and radii of the two planets more precisely than before. We find that the USP K2-106b has a density consistent with an Earth-like composition, and K2-106c is a low-density planet that presumably has an extended atmosphere. We measure a radius of Rp = 1.676-0.037+0.037 R⊕, a mass of Mp = 7.80-0.70+0.71 M⊕ and a density of ρ = 9.09-0.98+0.98 gcm-3 for K2-106b. For K2-106c, we derive Rp = 2.84-0.08+0.10 R⊕, Mp = 7.3-2.4+2.5 M⊕, and a density of ρ = 1.72-0.58+0.66 gcm-3. We finally discuss the possible structures of the two planets with respect to other low-mass planets.

KW - planetary systems

KW - planets and satellites: composition

KW - planets and satellites: fundamental parameters

KW - planets and satellites: individual K2-106b and K2-106c

KW - stars: fundamental parameters

KW - stars: late-type

U2 - 10.1093/mnras/stae494

DO - 10.1093/mnras/stae494

M3 - Article

SN - 0035-8711

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

ER -

A new mass and radius determination of the ultra-short period planet K2-106b and the fluffy planet K2-106c

Abstract

Bibliographical note

Keywords

Access to Document

Fingerprint

Projects

H2020_ERC_BEBOP

Cite this