TOI-2458 b: A mini-Neptune consistent with in situ hot Jupiter formation
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F25%3A00617428" target="_blank" >RIV/67985815:_____/25:00617428 - isvavai.cz</a>
Result on the web
<a href="https://hdl.handle.net/11104/0365971" target="_blank" >https://hdl.handle.net/11104/0365971</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1051/0004-6361/202451057" target="_blank" >10.1051/0004-6361/202451057</a>
Alternative languages
Result language
angličtina
Original language name
TOI-2458 b: A mini-Neptune consistent with in situ hot Jupiter formation
Original language description
We report on the discovery and spectroscopic confirmation of TOI-2458 b, a transiting mini-Neptune around an F-type star leaving the main-sequence with a mass of M-star = 1.05 +/- 0.03 M-circle dot, a radius of R-star = 1.31 +/- 0.03 R-circle dot, an effective temperature of T-eff = 6005 +/- 50 K, and a metallicity of0.10 +/- 0.05 dex. By combining TESS photometry with high-resolution spectra acquired with the HARPS spectrograph, we found that the transiting planet has an orbital period of3.74 days, a mass of M-p = 13.31 +/- 0.99 M-circle plus and a radius of R-p = 2.83 +/- 0.20 R-circle plus. The host star TOI-2458 shows a short activity cycle of similar to 54 days revealed in the HARPS S-index and Ha times series. We took the opportunity to investigate other F stars showing activity cycle periods comparable to that of TOI-2458 and found that they have shorter rotation periods than would be expected based on the gyrochronology predictions. In addition, we determined TOI-2458's stellar inclination angle to be i(*) = 10.6(-10.6)(+13.3) degrees. We discuss that both phenomena (fast stellar rotation and planet orbit inclination) could be explained by in situ formation of a hot Jupiter interior to TOI-2458 b. It is plausible that this hot Jupiter was recently engulfed by the star. Analysis of HARPS spectra has identified the presence of another planet with a period of P = 16.55 +/- 0.06 days and a minimum mass of M-p sin i = 10.22 +/- 1.90 M-circle plus. Using dynamical stability analysis, we constrained the mass of this planet to the range M-c similar or equal to (10, 25) M-circle plus.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10308 - Astronomy (including astrophysics,space science)
Result continuities
Project
Result was created during the realization of more than one project. More information in the Projects tab.
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Astronomy & Astrophysics
ISSN
0004-6361
e-ISSN
1432-0746
Volume of the periodical
693
Issue of the periodical within the volume
Jan.
Country of publishing house
FR - FRANCE
Number of pages
19
Pages from-to
A235
UT code for WoS article
001404890500009
EID of the result in the Scopus database
2-s2.0-85216404674