J/other/NatAs/5.640 MW chronologically dating early assembly (Montalban+, 2021)
Chronologically dating the early assembly of the Milky Way.
Montalban J., Mackereth J.T., Miglio A., Vincenzo F., Chiappini C.,
Buldgen G., Mosser B., Noels A., Scuflaire R., Vrard M., Willett E.,
Davies G.R., Hall O.J., Nielsen M.B., Khan S., Rendle B.M.,
Van Rossem W.E., Ferguson J.W., Chaplin W.J.
<Nature Astronomy, 5, 640-647 (2021)>
=2021NatAs...5..640M 2021NatAs...5..640M (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Stars, variable ; Asteroseismology ;
Effective temperatures ; Stars, masses ; Stars, ages
Abstract:
The standard cosmological model predicts that galaxies are built
through hierarchical assembly on cosmological timescales. The Milky
Way, like other disk galaxies, underwent violent mergers and accretion
of small satellite galaxies in its early history. Owing to Gaia Data
Release 2 and spectroscopic surveys, the stellar remnants of such
mergers have been identified. The chronological dating of such events
is crucial to uncover the formation and evolution of the Galaxy at
high redshift, but it has so far been challenging due to difficulties
in obtaining precise ages for these oldest stars. Here we combine
asteroseismology the study of stellar oscillations with kinematics
and chemical abundances to estimate precise stellar ages (∼11%) for a
sample of stars observed by the Kepler space mission. Crucially, this
sample includes not only some of the oldest stars that were formed
inside the Galaxy but also stars formed externally and subsequently
accreted onto the Milky Way. Leveraging this resolution in age, we
provide compelling evidence in favour of models in which the Galaxy
had already formed a substantial population of its stars (which now
reside mainly in its thick disk) before the infall of the satellite
galaxy Gaia-Enceladus/Sausage around 10 billion years ago.
Description:
Stellar parameters for the final sample of 95 targets.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables1.dat 108 95 Stellar parameters for the final sample
of 95 targets
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
Byte-by-byte Description of file: tables1.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC KIC identification number
10 A1 --- Group Selection group
12 I1 --- Nmodes Number of radial modes detected
14- 19 F6.2 uHz numax Maximun frequency value
21- 24 F4.2 uHz e_numax Maximun frequency value error
26- 31 F6.3 uHz deltanu Large frequency separation from linear
fitting of individual frequencies
33- 36 I4 K Teff Effective temperature from APOGEE-DR14
38- 40 I3 K e_Teff Effective temperature error
42- 46 F5.2 [-] [Fe/H] Metallicity from APOGEE-DR14
48- 51 F4.2 [-] [alpha/Fe] Abundance of alpha-elements from APOGEE-DR14
53- 57 F5.3 --- ecc Orbital eccentricity
59- 62 F4.2 Msun Mass16 16th percentile of Mass
64- 67 F4.2 Msun Mass Mass
69- 72 F4.2 Msun Mass64 64th percentile of Mass
74- 78 F5.2 Rsun Rad16 16th percentile of Radius
80- 84 F5.2 Rsun Rad Radius
86- 90 F5.2 Rsun Rad64 64th percentile of Radius
92- 96 F5.2 Gyr Age16 16th percentile of Age
98-102 F5.2 Gyr Age Age
104-108 F5.2 Gyr Age64 64th percentile of Age
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 07-Aug-2023