J/A+A/695/A27 Gas-giant planet-metallicity correlation (Maldonado+, 2025)
Intermediate-mass stars and the origin of the gas-giant planet-metallicity
correlation.
Maldonado J., Mirouh G.M., Mendigutia I., Montesinos B., Gragera-Mas J.L.,
Villaver E.
<Astron. Astrophys. 695, A27 (2025)>
=2025A&A...695A..27M 2025A&A...695A..27M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, giant ; Exoplanets ;
Stars, masses ; Abundances, [Fe/H] ; Stars, ages
Keywords: techniques: spectroscopic - planets and satellites: formation -
stars: abundances - stars: early-type
Abstract:
Currently, the number of known planets around intermediate-mass stars
(1.5M☉<M*<3.5M☉) is rather low and, as a consequence,
models of planet formation have their strongest observational evidence
on the chemical signature of mostly low-mass (FGK) Main-Sequence (MS)
stars with planets.
We aim to test whether the well-known correlation between the
metallicity of the star and the presence of gas-giant planets found
for MS low-mass stars still holds for intermediate-mass stars. In
particular, we aim to understand whether or not the planet-metallicity
relation changes as stars evolve from the pre-MS to the red giant
branch.
We compile the basic stellar parameters (metallicity, mass and age) of
a sample of intermediate-mass stars at different evolutionary phases
with and without evidence suggesting that they host gas-giant planets.
The metallicities of the different susbsamples are compared and set in
the context of current models of planet formation and stellar
evolution.
Our results confirm that pre-MS stars with transitional discs with
gaps show lower metallicities than pre-MS with flat discs. We show a
tendency of intermediate-mass stars in the MS to follow the gas-giant
planet-metallicity correlation, although the differences in metal
content between planet and non-planet hosts are rather modest and the
strength of the correlation is significantly lower than for the less
massive FGK MS stars. For stars in the red giant branch, we find a
strong planet-metallicity correlation, compatible with that found for
FGK MS stars. We discuss how the evolution of the mass in the
convective zone of the star's interior might affect the measured
metallicity of the star. In particular, if the planet-metallicity
correlation were of primordial origin, one would expect it to be
stronger for less massive stars, as they are longer convective during
the stellar evolution. However, within our sample, we find the
opposite.
The lack of a well-established planet-metallicity correlation in
pre-MS and MS intermediate-mass stars can be explained by a scenario
in which planet formation leads to an accretion of metal-poor material
on the surface of the star. As intermediate-mass stars are mainly
radiative the metallicity of the star does not reflect its bulk
composition but the composition of the accreted material. When the
star leaves the MS and develops a sizeable convective envelope, a
strong-planet metallicity correlation is recovered. Thus, our results
are in line with core-accretion
Description:
File tableA.1.dat lists the properties of the pre-MS stars. Parameters
are taken from Guzman-Diaz et al., 2021A&A...650A.182G 2021A&A...650A.182G,
Cat. J/A+A/650/A182 and 2023A&A...671A.140G 2023A&A...671A.140G.
File tableA.2.dat provides the properties of the MS stars. The sample
is drawn from Saffe et al., 2021A&A...647A..49S 2021A&A...647A..49S, Cat. J/A+A/647/A49
and 2022A&A...668A.157S 2022A&A...668A.157S.
File tableA.3.dat lists the properties of the red giant stars. The
sample comes mainly from Maldonado et al., 2013A&A...554A..84M 2013A&A...554A..84M,
Cat. J/A+A/554/A84 and Maldonado & Villaver, 2016A&A...588A..98M 2016A&A...588A..98M,
Cat. J/A+A/588/A98.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 60 44 Properties of the pre-MS sample
(corrected version, 29-Apr-2025)
tablea2.dat 56 28 Properties of the MS sample
tablea3.dat 51 59 Properties of the red giant stars sample
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See also:
J/A+A/554/A84 : Abundances of evolved stars (Maldonado+, 2013)
J/A+A/588/A98 : Metallicities and abundances of evolved stars
(Maldonado+, 2016)
J/A+A/650/A182 : Homogeneous study of Herbig Ae/Be stars (Guzman-Diaz+, 2021)
J/A+A/647/A49 : Chemical analysis of early-type stars with planets
(Saffe+, 2021)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Star Star identifier
15- 16 A2 --- Group Group I/II classification
19- 23 I5 [K] Teff Effective temperature
25- 27 I3 [K] e_Teff Uncertainty on Teff
29- 33 F5.2 [Sun] [Fe/H] Metallicity
35- 38 F4.2 [Sun] e_[Fe/H] Uncertainty on [Fe/H]
40 A1 --- l_Mass Upper limit flag on Mass
41- 44 F4.2 [Sun] Mass Stellar mass
46- 49 F4.2 [Sun] e_Mass ?=- Uncertainty on Mass (1)
51 A1 --- l_Age Upper limit flag on Age
52- 55 F4.1 [Myr] Age ? Age
57- 60 F4.2 [Myr] e_Age ? Uncertainty on Age (1)
--------------------------------------------------------------------------------
Note (1): A missing value indicates an upper limit.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Star Star identifier
11 A1 --- Planet [y] Planet_host (1)
13- 17 I5 [K] Teff Effective temperature
19- 21 I3 [K] e_Teff Uncertainty on Teff
23- 27 F5.2 [Sun] [Fe/H] Metallicity
29- 32 F4.2 [Sun] e_[Fe/H] Uncertainty on [Fe/H]
34- 38 F5.3 [Sun] Mass Stellar mass
40- 44 F5.3 [Sun] e_Mass Uncertainty on Mass
46- 50 F5.3 [Gyr] Age Age
52- 56 F5.3 [Gyr] e_Age Uncertainty on Age
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Note (1): 'y' indicates that the star hosts at least one gas-giant planet.
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Byte-by-byte Description of file: tablea3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Star Star identifier
12 A1 --- Planet [y] Planet_host (1)
14- 17 I4 [K] Teff Effective temperature
19- 20 I2 [K] e_Teff Uncertainty on Teff
22- 26 F5.2 [Sun] [Fe/H] Metallicity
28- 31 F4.2 [Sun] e_[Fe/H] Uncertainty on [Fe/H]
33- 36 F4.2 [Sun] Mass Stellar mass
38- 41 F4.2 [Sun] e_Mass Uncertainty on Mass
43- 46 F4.2 [Gyr] Age Age
48- 51 F4.2 [Gyr] e_Age Uncertainty on Age
--------------------------------------------------------------------------------
Note (1): 'y' indicates that the star hosts at least one gas-giant planet.
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Acknowledgements:
Jesus Maldonado, jesus.maldonado(at)inaf.it
History:
28-Feb-2025: on-line version
29-Apr-2025: corrected table A1
(End) Patricia Vannier [CDS] 03-Feb-2025