J/A+A/678/A138 Toward more accurate RR Lyrae metallicities (Kovacs+, 2023)
Toward more accurate RR Lyrae metallicities.
Kovacs G., Jurcsik J.
<Astron. Astrophys. 678, A138 (2023)>
=2023A&A...678A.138K 2023A&A...678A.138K (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Stars, horizontal branch ; Abundances, [Fe/H]
Keywords: stars: abundances - stars: variables: RR Lyrae -
stars: horizontal branch
Abstract:
By using a large sample of fundamental mode RR Lyrae stars with
published spectroscopic iron abundances and gravities, we point out
the importance of correcting these abundances by using more accurate
temporal gravities. For the 197 stars with multiple spectra we find
overall [Fe/H] standard deviations of 0.167 (as published), 0.145
(shifted by data source zero points) and 0.121 (both zero point
shifted and corrected to the static gravity). These improvements are
significant at the ∼2 sigma level at each correction step, leading to
a clearly significant improvement after both corrections applied. The
higher quality of the gravity-corrected metallicities is strongly
supported also by the tighter correlation with the metallicities
predicted from the period and Fourier phase phi31. This work
underlines the need for using some external estimates of the temporal
gravity in the chemical abundance analysis rather than relying on a
full-fetched spectrum fit that leads to large correlated errors in the
estimated parameters.
Description:
These are the data files relevant in producing the results presented
in the paper.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 77 1109 *Star-by-star and source-by-source HDS parameters
for 269 stars
tablea2.dat 185 269 *Average HDS metallicities
tablea3.dat 89 392 *LDS, HDS and combined metallicities
tablea4.dat 88 676 *Fourier parameters for 394 stars
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Note on tablea*.dat: all files have detailed description in their comment lines
(above the headers) to aid full understanding of their content.
Headers and comment lines start with hashmark.
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Byte-by-byte Description of file (#): tablea1.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Star Name of the variable
22- 27 F6.4 [K] logTeff log effective temperature,
as given by the source
31- 35 F5.3 [cm/s2] loggS Surface gravity, as given by the source
39- 43 F5.3 [cm/s2] loggP An approximation of the static surface gravity
48- 53 F6.3 [-] [Fe/H]S Metallicity, [Fe/H], as given by the source
58- 63 F6.3 [-] [Fe/H]P logg and zero point (ZP) corrected [Fe/H]
66- 71 F6.3 --- DZP Source-dependent differential ZP correction
74- 77 A4 --- r_[Fe/H] Acronym for the [Fe/H] source (G1)
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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- 20 A20 --- Star Name of the variable
23- 29 F7.4 [-] [Fe/H]S Mean of the original (source given) [Fe/H]
32- 37 F6.4 [-] e_[Fe/H]S Standard error of the mean
40- 46 F7.4 [-] [Fe/H]P Mean of the corrected [Fe/H] (1)
49- 54 F6.4 [-] e_[Fe/H]P Standard error of the mean
58- 59 I2 --- Nsp Number of spectra
62- 65 A4 --- Ref1 List of data sources (G1)
67- 70 A4 --- Ref2 List of data sources (G1)
72- 75 A4 --- Ref3 List of data sources (G1)
77- 80 A4 --- Ref4 List of data sources (G1)
82- 85 A4 --- Ref5 List of data sources (G1)
87- 90 A4 --- Ref6 List of data sources (G1)
92- 95 A4 --- Ref7 List of data sources (G1)
97-100 A4 --- Ref8 List of data sources (G1)
102-105 A4 --- Ref9 List of data sources (G1)
107-110 A4 --- Ref10 List of data sources (G1)
112-115 A4 --- Ref11 List of data sources (G1)
117-120 A4 --- Ref12 List of data sources (G1)
122-125 A4 --- Ref13 List of data sources (G1)
127-130 A4 --- Ref14 List of data sources (G1)
132-135 A4 --- Ref15 List of data sources (G1)
137-140 A4 --- Ref16 List of data sources (G1)
142-145 A4 --- Ref17 List of data sources (G1)
147-150 A4 --- Ref18 List of data sources (G1)
152-155 A4 --- Ref19 List of data sources (G1)
157-160 A4 --- Ref20 List of data sources (G1)
162-165 A4 --- Ref21 List of data sources (G1)
167-170 A4 --- Ref22 List of data sources (G1)
172-175 A4 --- Ref23 List of data sources (G1)
177-180 A4 --- Ref24 List of data sources (G1)
182-185 A4 --- Ref25 List of data sources (G1)
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Note (1): [Fe/H]P is the mean of the logg- and zero point-corrected [Fe/H]
values, as described in the paper.
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Byte-by-byte Description of file (#): tablea3.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Star Name of the variable
24- 29 F6.3 [-] LA94a Published [Fe/H] by Layden
(1994AJ....108.1016L 1994AJ....108.1016L, Cat. J/AJ/108/1016)
31- 36 F6.3 [-] LA94b Transformed [Fe/H], as given in the paper (1)
39 I1 --- NLA Number of spectra in Layden
(1994AJ....108.1016L 1994AJ....108.1016L, Cat. J/AJ/108/1016)
43- 48 F6.3 [-] SU94a Published [Fe/H] by Suntzeff
(1994AJ....108.1016L 1994AJ....108.1016L, Cat. J/AJ/108/1016)
50- 55 F6.3 [-] SU94b Transformed [Fe/H], as given in the paper (2)
57- 58 I2 --- NSU Number of spectra in Suntzeff
(1994AJ....108.1016L 1994AJ....108.1016L, Cat. J/AJ/108/1016)
62- 67 F6.3 [-] HDS Average HDS [Fe/H], as given in the paper
69- 70 I2 --- NHD Number of HDS spectra (3)
74- 79 F6.3 [-] [Fe/H]avg Average [Fe/H] from the LDS and HDS sources,
weighted by the number of spectra in
each source
82- 86 F5.3 [-] e_[Fe/H]avg Error assigned to [Fe/H]avg
88- 89 I2 --- NLD LDS exclusivity flag (4)
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Note (1): Transformed [Fe/H] from LA94 via Table 2 of the paper (the
transformation eliminates the systematic differences between the HDS and
LDS metallicities).
Note (2): Transformed [Fe/H] from SU94 via Table 2 of the paper.
Note (3): the same value as given in column [Fe/H]P of tablea1.dat.
Note (4): Notes:
- All single spectrum (i.e., NLA+NSU+NHD=1) items have the same (arbitrary)
[Fe/H] error assigned to (which is set equal to 0.300dex).
- For single source LDS items with multiple spectra, the assigned errors
are given by 0.300/sqrt(Nsp), where Nsp is the number of spectra.
- If HDS is the only source, but it has multiple spectra, the errors are
taken from tablea1.dat (containing the average HDS metallicities and
their errors)
- If there are multiple sources available (such as LA94+SU94, LA94+HDS,
SU94+HDS or LA94+SU94+HDS), then the error is calculated from the RMS
(with respect to [Fe/H]avg) of the various source values by dividing
this RMS with the square root of the number of the available sources
(2 or 3).
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Byte-by-byte Description of file (#): tablea4.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Star Name of the variable
22- 31 F10.8 d Per Fundamental pulsation period
34- 38 F5.3 mag Amptot Total (peak-to-peak) amplitude
41- 45 F5.3 rad phi31 Epoch-independent 3rd-harmonics Fourier phase
48- 52 F5.3 rad phi41 Epoch-independent 4th-harmonics Fourier phase
55- 58 I4 --- N Number of data points
61- 66 F6.4 mag RMS Root mean square of the residuals
69- 70 I2 --- NF Number of Fourier components
73- 76 I4 d TimeTot Total time span of the data analyzed
79 I1 --- Qual [0/3] Quality of the fit
82- 88 A7 --- Tel Telescope (system) used in the observations
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Global notes:
Note (G1): References as follows:
an18 = Andrievsky et al., 2018PASP..130b4201A 2018PASP..130b4201A
an21 = Andrievsky et al., 2021AN....342..997A 2021AN....342..997A
ch17 = Chadid et al., 2017ApJ...835..187C 2017ApJ...835..187C
cl95 = Clementini et al., 1995AJ....110.2319C 1995AJ....110.2319C, Cat. J/AJ/110/2319
cr21 = Crestani et al., 2021ApJ...914...10C 2021ApJ...914...10C, Cat. J/ApJ/914/10
fe96 = Fernley & Barnes, 1996A&A...312..957F 1996A&A...312..957F
fe97 = Fernley & Barnes, 1997A&AS..125..313F 1997A&AS..125..313F, Cat. J/A+AS/125/313
fo11 = For et al., 2011ApJS..197...29F 2011ApJS..197...29F, Cat. J/ApJS/197/29
gala = Buder et al., 2021MNRAS.506..150B 2021MNRAS.506..150B, Cat. J/MNRAS/506/150
la96 = Lambert et al., 1996ApJS..103..183L 1996ApJS..103..183L
lal5 = Luo et al., LAMOST DR5, Cat. V/164; LAMOST DR7, Cat. V/156
lam5 = Xiang et al., 2019ApJS..245...34X 2019ApJS..245...34X, Cat. J/ApJS/245/34
li13 = Liu et al., 2013RAA....13.1307L 2013RAA....13.1307L
ne13 = Nemec et al., 2013ApJ...773..181N 2013ApJ...773..181N
pa15 = Pancino et al., 2015MNRAS.447.2404P 2015MNRAS.447.2404P, Cat. J/MNRAS/447/2404
so97 = Solano et al., 1997A&AS..125..321S 1997A&AS..125..321S, Cat. J/A+AS/125/321
ta22 = Takeda, 2022MNRAS.514.2450T 2022MNRAS.514.2450T
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Acknowledgements:
Geza Kovacs, kovageza(at)gmail.com
(End) Patricia Vannier [CDS] 03-Sep-2023