In:
The Astronomical Journal, American Astronomical Society, Vol. 166, No. 4 ( 2023-10-01), p. 165-
Abstract:
Observations and statistical studies have shown that giant planets are rare around M dwarfs compared with Sun-like stars. The formation mechanism of these extreme systems has remained under debate for decades. With the help of the TESS mission and ground-based follow-up observations, we report the discovery of TOI-4201b, the most massive and densest hot Jupiter around an M dwarf known so far with a radius of 1.22 ± 0.04 R J and a mass of 2.48 ± 0.09 M J , about 5 times heavier than most other giant planets around M dwarfs. It also has the highest planet-to-star mass ratio ( q ∼ 4 × 10 −3 ) among such systems. The host star is an early M dwarf with a mass of 0.61 ± 0.02 M ⊙ and a radius of 0.63 ± 0.02 R ⊙ . It has significant supersolar iron abundance ([Fe/H] = 0.52 ± 0.08 dex). However, interior structure modeling suggests that its planet TOI-4201b is metal-poor, which challenges the classical core-accretion correlation of stellar−planet metallicity, unless the planet is inflated by additional energy sources. Building on the detection of this planet, we compare the stellar metallicity distribution of four planetary groups: hot/warm Jupiters around G/M dwarfs. We find that hot/warm Jupiters show a similar metallicity dependence around G-type stars. For M-dwarf host stars, the occurrence of hot Jupiters shows a much stronger correlation with iron abundance, while warm Jupiters display a weaker preference, indicating possible different formation histories.
Type of Medium:
Online Resource
ISSN:
0004-6256
,
1538-3881
DOI:
10.3847/1538-3881/acf56d
Language:
Unknown
Publisher:
American Astronomical Society
Publication Date:
2023
detail.hit.zdb_id:
2207625-6
detail.hit.zdb_id:
2003104-X
SSG:
16,12
