A new mass and radius determination of the ultra-short period planet K2-106b and the fluffy planet K2-106c
(2024) In Monthly Notices of the Royal Astronomical Society 529(1). p.141-154- Abstract
Ultra-short period planets (USPs) have orbital periods of less than 1 d. 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 d. 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 K2-106 b has a density consistent with an Earth-like composition, and K2-106 c is a low-density planet... (More)
Ultra-short period planets (USPs) have orbital periods of less than 1 d. 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 d. 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 K2-106 b has a density consistent with an Earth-like composition, and K2-106 c is a low-density planet that presumably has an extended atmosphere. We measure a radius of R p = 1 . 676 + 0 . 037 -0 . 037 R ⊕, a mass of M p = 7 . 80 + 0 . 71 -0 . 70 M ⊕, and a density of ρ= 9 . 09 + 0 . 98 -0 . 98 g cm -3 for K2-106 b. For K2-106 c, we derive R p = 2 . 84 + 0 . 10 -0 . 08 R ⊕, M p = 7 . 3 + 2 . 5 -2 . 4 M ⊕, and a density of ρ= 1 . 72 + 0 . 66 -0 . 58 g cm -3 . We finally discuss the possible structures of the two planets with respect to other low-mass planets.
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- author
- Guenther, E. W. ; Goffo, E. ; Sebastian, D. ; Smith, A. M.S. ; Persson, C. M. ; Fridlund, M. ; Gandolfi, D. and Korth, J. LU
- organization
- publishing date
- 2024-03
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- planets and satellites: fundamental parameters, planets and satellites: individual: K2-106b and K2-106c, planets and satellites: interiors, stars: fundamental parameters, stars: late-type
- in
- Monthly Notices of the Royal Astronomical Society
- volume
- 529
- issue
- 1
- pages
- 14 pages
- publisher
- Oxford University Press
- external identifiers
-
- scopus:85186400979
- ISSN
- 0035-8711
- DOI
- 10.1093/mnras/stae494
- language
- English
- LU publication?
- yes
- id
- 4133e420-76cb-4223-ba06-c7eae395ca1f
- date added to LUP
- 2024-03-26 15:32:13
- date last changed
- 2024-03-26 15:32:47
@article{4133e420-76cb-4223-ba06-c7eae395ca1f,
abstract = {{<p>Ultra-short period planets (USPs) have orbital periods of less than 1 d. 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 d. 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 K2-106 b has a density consistent with an Earth-like composition, and K2-106 c is a low-density planet that presumably has an extended atmosphere. We measure a radius of R p = 1 . 676 + 0 . 037 -0 . 037 R ⊕, a mass of M p = 7 . 80 + 0 . 71 -0 . 70 M ⊕, and a density of ρ= 9 . 09 + 0 . 98 -0 . 98 g cm -3 for K2-106 b. For K2-106 c, we derive R p = 2 . 84 + 0 . 10 -0 . 08 R ⊕, M p = 7 . 3 + 2 . 5 -2 . 4 M ⊕, and a density of ρ= 1 . 72 + 0 . 66 -0 . 58 g cm -3 . We finally discuss the possible structures of the two planets with respect to other low-mass planets.</p>}},
author = {{Guenther, E. W. and Goffo, E. and Sebastian, D. and Smith, A. M.S. and Persson, C. M. and Fridlund, M. and Gandolfi, D. and Korth, J.}},
issn = {{0035-8711}},
keywords = {{planets and satellites: fundamental parameters; planets and satellites: individual: K2-106b and K2-106c; planets and satellites: interiors; stars: fundamental parameters; stars: late-type}},
language = {{eng}},
number = {{1}},
pages = {{141--154}},
publisher = {{Oxford University Press}},
series = {{Monthly Notices of the Royal Astronomical Society}},
title = {{A new mass and radius determination of the ultra-short period planet K2-106b and the fluffy planet K2-106c}},
url = {{http://dx.doi.org/10.1093/mnras/stae494}},
doi = {{10.1093/mnras/stae494}},
volume = {{529}},
year = {{2024}},
}