J/A+A/684/A28 Evolution of lithium in FGK dwarfs (Llorente de Andres+, 2024)
The evolution of lithium in FGK dwarf stars.
Influence of planets and Galactic migration.
Llorente de Andres, F., de la Reza R., Cruz P., Cuenda-Munoz D.,
Alfaro E. J., Chavero C., Cifuentes C.
<Astron. Astrophys. 684, A28 (2024)>
=2024A&A...684A..28L 2024A&A...684A..28L (SIMBAD/NED BibCode)
ADC_Keywords: Stars, dwarfs ; Stars, G-type ; Abundances ; Stars, diameters ;
Optical
Keywords: planet-star interactions - stars: abundances - stars: solar-type -
Galaxy: stellar content
Abstract:
This work aims to investigate the behaviour of the lithium abundance
in stars with and without detected planets. Our study is based on a
sample of 1332 FGK main-sequence stars with measured lithium
abundances, for 257 of which planets were detected. Our method reviews
the sample statistics and is addressed specifically to the influence
of tides and orbital decay, with special attention to planets on close
orbits, whose stellar rotational velocity is higher than the orbital
period of the planet. In this case, tidal effects are much more
pronounced. The analysis also covers the orbital decay on a short
timescale, with planets spiralling into their parent star.
Furthermore, the sample allows us to study the relation between the
presence of planets and the physical properties of their host stars,
such as the chromospheric activity, metallicity, and lithium
abundance. In the case of a strong tidal influence, we cannot infer
from any of the studies described that the behaviour of Li differs
between stars that host planets and those that do not. Our sample
includes stars with super-solar metallicity ([Fe/H]>0.15dex) and a
low lithium abundance (A(Li)<1.0dex). This enabled us to analyse
scenarios of the origin and existence of these stars. Considering the
possible explanation of the F dip, we show that it is not a plausible
scenario. Our analysis is based on a kinematic study and concludes
that the possible time that elapsed in the travel from their birth
places in the central regions of the Galaxy to their current positions
in the solar neighbourhood is not enough to explain the high lithium
depletion. It is remarkable that those of our high-metallicity
low-lithium stars with the greatest eccentricity (e>0.2) are closest
to the Galactic centre. A dedicated study of a set of high-metallicity
low-Li stars is needed to test the migration-depletion scenario.
Description:
Table A.1 shows the parameters of stars with detected planets, as
described in Sect. 2. This table is complementary to the table
published in Llorente de Andres et al. (2021A&A...654A.137L 2021A&A...654A.137L, Cat.
J/A+A/654/A137). The last column presents the calculated orbital decay
(as logOD), as described Sect. 3.
Table A.2 shows [Ti/H] and [Ti/Fe] values for the objects with a
negative Galactic velocity, U, that are older than 8Ga, as described
in Sect. 5.2. Values marked with an asterisk are [alpha/Fe] instead,
when [Ti/Fe] is not available.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 165 256 Parameters of stars and their host planets
tablea2.dat 87 142 [Ti/H] and [Ti/Fe] values for objects with
negative U that are older than 8 Ga
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See also:
J/A+A/654/A137 : Evolution of Li in FGK dwarf stars (Llorente de Andres+, 2021)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Id Identifier
13- 25 A13 --- Name Name
27- 28 I2 h RAh Right Ascension (J2000)
30- 31 I2 min RAm Right Ascension (J2000)
33- 37 F5.2 s RAs Right Ascension (J2000)
39 A1 --- DE- Declination sign (J2000)
40- 41 I2 deg DEd Declination (J2000)
43- 44 I2 arcmin DEm Declination (J2000)
46- 49 F4.1 arcsec DEs Declination (J2000)
51- 64 A14 --- SpType Spectral type
66 I1 --- Nplanet Number of planets hosted by the star
68- 73 F6.3 Mjup Mt Total mass of the planets in Jovian units
75- 87 F13.8 d P ? Orbital period of the closest planet
89- 94 F6.4 AU a ? Semi-major axis of the closest planet
96-102 F7.5 --- e Eccentricity of the closest planet
104-112 F9.6 d Prot ? Stellar rotational period
114-132 A19 --- r_Prot Stellar rotational period reference
134-138 F5.3 Rsun Rad Stellar radius
140-158 A19 --- r_Rad Stellar radius reference
160-165 F6.3 [-] logOD ? Decimal logarithm of the orbital decay
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Id Identifier
14- 25 A12 --- Name Name
27- 28 I2 h RAh Right Ascension (J2000)
30- 31 I2 min RAm Right Ascension (J2000)
33- 37 F5.2 s RAs Right Ascension (J2000)
39 A1 --- DE- Declination sign (J2000)
40- 41 I2 deg DEd Declination (J2000)
43- 44 I2 arcmin DEm Declination (J2000)
46- 49 F4.1 arcsec DEs Declination (J2000)
51- 55 F5.2 --- [Ti/H] ? Titanium to Hydrogen ratio
57- 61 F5.2 --- [Ti/Fe] ? Titanium to Iron ratio
63- 81 A19 --- r_[Ti/H] References for the Titanium ratios
83- 87 A5 --- Alpha [False True] Boolean flag for [alpha/Fe]
instead of [Ti/Fe]
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Acknowledgements:
Felix Llorente de Andres, fllorente(at)cab.inta-csic.es
(End) Patricia Vannier [CDS] 05-Mar-2024