J/MNRAS/485/L68 The evolution of stellar rotation (Lorenzo-Oliveira+, 2019)
Constraining the evolution of stellar rotation using solar twins.
Lorenzo-Oliveira D., Melendez J., Yana Galarza J., Ponte G.,
dos Santos L.A., Spina L., Bedell M., Ramirez I., Bean J.L., Asplund M.
<Mon. Not. R. Astron. Soc., 485, L68-72 (2019)>
=2019MNRAS.485L..68L 2019MNRAS.485L..68L (SIMBAD/NED BibCode)
ADC_Keywords: Stars, fundamental ; Stars, masses ; Stars, G-type ; Optical
Keywords: Sun: rotation - stars: fundamental parameters - stars: rotation -
stars: solar-type
Abstract:
The stellar rotation versus age relation is commonly considered a
useful tool to derive reliable ages for Sun-like stars. However, in
the light of Kepler data, the presence of apparently old and fast
rotators that do not obey the usual gyrochronology relations led to
the hypothesis of weakened magnetic breaking in some stars. In this
letter, we constrain the solar rotation evolutionary track using solar
twins. Predicted rotational periods as a function of mass, age,
[Fe/H], and given critical Rossby number (Rocrit) were estimated for
the entire rotational sample. Our analysis favours the smooth
rotational evolution scenario and suggests that if the magnetic
weakened breaking scenario takes place at all, it should arise after
Rocrit≳2.29 or ages ≳5.3Gyr (at 95 per cent confidence level).
Description:
We compiled 79 solar twins (plus the Sun) presented in Spina et al.
(2018MNRAS.474.2580S 2018MNRAS.474.2580S, Cat. J/MNRAS/474/2580). Our sample was
extensively observed over the years (2011-2016) with HARPS
spectrograph (Mayor et al. 2003Msngr.114...20M 2003Msngr.114...20M) fed by the 3.6m
telescope at La Silla Observatory, to search for planets around solar
twins (program 188.C-0265, Melendez et al. 2017A&A...597A..34M 2017A&A...597A..34M). To
prevent the inclusion of anomalously fast rotators due to binarity
effects, 17 spectroscopic binary (SB) stars and other solar twins with
a close companion within 4in. were discarded from the analysis (dos
Santos et al. 2017MNRAS.472.3425D 2017MNRAS.472.3425D). Other interesting solar twins
spectroscopically analysed in the past by our group were added to our
sample (HIP30503 and HIP78399 in Galarza, Melendez & Cohen
2016A&A...589A..65G 2016A&A...589A..65G). The resulting HARPS sample of this work is
composed of 65 stars.
In order to estimate rotational velocities and other stellar
parameters of interest, we used the updated atmospheric parameters
(Teff, logg, [Fe/H], and [α/Fe]) provided by Spina et al.
(2018MNRAS.474.2580S 2018MNRAS.474.2580S, Cat. J/MNRAS/474/2580). Gaia DR2 G band
photometry and parallaxes (Gaia Collaboration 2018A&A...616A...1G 2018A&A...616A...1G,
Cat. I/345) were combined to the spectroscopic data to obtain stellar
ages, masses, logg, and other evolutionary parameters following the
procedures described in Grieves et al. (2018MNRAS.481.3244G 2018MNRAS.481.3244G, Cat.
J/MNRAS/481/3244).
Stellar atmospheric and evolutionary parameters, projected Prot, and
other relevant information of the entire sample is shown in tables 1a,
1b and 1c.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1a.dat 103 15 Relevant parameters of solar twins stars
table1b.dat 83 40 Relevant parameters for our rotation sample of
solar twins stars analysed in this paper
(selected sample)
table1c.dat 62 5 Averaged parameters for our rotation sample of
solar twins stars
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Byte-by-byte Description of file: table1a.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Star name
13- 15 F3.1 Gyr Age Star age
17- 19 F3.1 Gyr e_Age Lower error on Age
21- 23 F3.1 Gyr E_Age Upper error on Age
25- 28 F4.2 Msun Mstar Star mass
30- 33 F4.2 Msun e_Mstar Error on Mstar
35- 40 F6.3 [-] [Fe/H] Iron to hydrogen abundance ratio
42- 46 F5.3 [-] e_[Fe/H] Error on [Fe/H]
48- 51 F4.1 d Psini ? Rotational period divided by the projection
factor sini
53- 55 F3.1 d e_Psini ? Error on Psini
57- 60 F4.1 d Prot Rotational period
62- 64 F3.1 d e_Prot Error on Prot
66- 69 F4.1 d ProtP Median rotational period
71- 74 F4.1 d e_ProtP Error on ProtP
76- 79 F4.1 d ProtPRo2 Median rotational period for Rocrit=2.0 (G1)
81- 83 F3.1 d e_ProtPRo2 Error on ProtPRo2
85-103 A19 --- Remarks References and remarks (1)
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Note (1): References as follows:
see17 = See et al. 2017MNRAS.466.1542S 2017MNRAS.466.1542S
suarez17 = Suarez Mascareno et al. 2017MNRAS.468.4772S 2017MNRAS.468.4772S
petit08 = Petit et al. 2008MNRAS.388...80P 2008MNRAS.388...80P
wright11 = Wright et al. 2011ApJ...743...48W 2011ApJ...743...48W, Cat. J/ApJ/743/48
mcquillan13 = McQuillan et al. 2013ApJ...775L..11M 2013ApJ...775L..11M, Cat. J/ApJ/775/L11
mazeh15 = Mazeh et al. 2015ApJ...801....3M 2015ApJ...801....3M, Cat. J/ApJ/801/3
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Byte-by-byte Description of file: table1b.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Star name
12- 14 F3.1 Gyr Age Star age
16- 18 F3.1 Gyr e_Age Lower error on Age
20- 22 F3.1 Gyr E_Age Upper error on Age
24- 27 F4.2 Msun Mstar Star mass
29- 32 F4.2 Msun e_Mstar Error on Mstar
34- 39 F6.3 [-] [Fe/H] Iron to hydrogen abundance ratio
41- 45 F5.3 [-] e_[Fe/H] Error on [Fe/H]
47- 50 F4.1 d Psini Rotational period divided by the projection
factor sini
52- 54 F3.1 d e_Psini Error on Psini
56- 59 F4.1 d Prot ? Rotational period
61- 63 F3.1 d e_Prot ? Error on Prot
65- 68 F4.1 d ProtP Median rotational period
70- 73 F4.1 d e_ProtP Error on ProtP
75- 78 F4.1 d ProtPRo2 Median rotational period for Rocrit=2.0 (G1)
80- 83 F4.1 d e_ProtPRo2 Error on ProtPRo2
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Byte-by-byte Description of file: table1c.dat
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Bytes Format Units Label Explanations
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1- 4 A4 Gyr BinAge Age bin on which the means where computed
6- 8 F3.1 Gyr Agemean Average of the star ages for each age bin
10- 12 F3.1 Gyr e_Agemean Error on Agemean
14- 17 F4.2 Msun Mstarmean Average of the star masses for each age bin
19- 22 F4.2 Msun e_Mstarmean Error on Mstarmean
24- 29 F6.3 [-] [Fe/H] Average iron to hydrogen abundance ratio
31- 35 F5.3 [-] e_[Fe/H] Error on [Fe/H]
37- 40 F4.1 d Psinimean Average rotational period divided by the
projection factor sini for each age bin
42- 44 F3.1 d e_Psinimean Error on Psini
46- 49 F4.1 d ProtPmean Average median rotational period for each
age bin
51- 53 F3.1 d e_ProtPmean Error on ProtPmean
55- 58 F4.1 d ProtPRo2mean Average median rotational period for
Rocrit=2.0 for each age bin (G1)
60- 62 F3.1 d e_ProtPRo2mean Error on ProtPRo2mean
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Global Notes:
Note (G1): Median rotational period obtained for a critical Rossby number Ro=2,
where Ro=Prot/τCZ with τCZ the convective turnover time
(Noyes et al. 1984ApJ...279..763N 1984ApJ...279..763N)
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 07-Sep-2022