J/A+A/661/A104 Physical parameters of classical Cepheids (da Silva+, 2022)
A new and homogeneous metallicity scale for Galactic classical Cepheids.
II. The abundance of iron and alpha elements.
da Silva R., Crestani J., Bono G., Braga V.F., D'Orazi V., Lemasle B.,
Bergemann M., Dall'Ora M., Fiorentino G., Francois P., Groenewegen M.A.T.,
Inno L., Kovtyukh V., Kudritzki R.-P., Matsunaga N., Monelli M.,
Pietrinferni A., Porcelli L., Storm J., Tantalo M., Thevenin F.
<Astron. Astrophys. 661, A104 (2022)>
=2022A&A...661A.104D 2022A&A...661A.104D (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Stars, variable ; Abundances ; Spectroscopy ; Optical
Keywords: Galaxy: disk - stars: abundances - stars: fundamental parameters -
stars: variables: Cepheids
Abstract:
Classical Cepheids are the most popular distance indicators and
tracers of young stellar populations. The key advantage is that they
are bright and they can be easily identified in Local Group and Local
Volume galaxies. Their evolutionary and pulsation properties depend on
their chemical abundances. The main aim of this investigation is to
perform a new and accurate abundance analysis of 20 calibrating
Galactic Cepheids. We used high spectral resolution
(R∼40000-115000) and high S/N spectra (∼400), covering the entire
pulsation cycle. We focused our attention on plausible systematics
that would affect the estimate of atmospheric parameters and elemental
abundances along the pulsation cycle. We cleaned the line list by
using atomic transition parameters based on laboratory measurements
and by removing lines that are either blended or that display
abundance variations along the pulsation cycle. The spectroscopic
approach we developed brings forward small dispersions in the
variation of the atmospheric parameters (sigma(Teff)∼50K,
sigma(logg)∼0.2dex, and sigma(xi)∼0.2km/s) as well as in the abundance
of both iron (≲0.05dex) and alpha elements (≲0.10dex) over the
entire pulsation cycle. We also provide new and accurate effective
temperature templates by splitting the calibrating Cepheids into four
different period bins, ranging from short to long periods. For each
period bin, we performed an analytical fit with Fourier series
providing theta=5040/Teff as a function of the pulsation phase. The
current findings are a good viaticum for tracing the chemical
enrichment of the Galactic thin disk by using classical Cepheids as a
fundamental stepping stone for further investigations into the more
metal-poor regime that is typical of Magellanic Cepheids.
Description:
The atomic parameters for a list of FeI and FeII atomic lines and for
a list of alpha elements (MgI, SiI, SiII, SI, CaI, CaII, TiI, and
TiII) are presented. A quality flag indicating if a line was used (1)
or not used (0) in the current work is also shown. The Fe lines were
used to derive the atmospheric parameters (effective temperature,
surface gravity, and microturbulent velocity) and the stellar
metallicity for each spectrum (collected with HARPS, FEROS, UVES,
and/or STELLA spectrographs) of the 20 calibrating Cepheids. The
atomic lines of the alpha elements were used to derive their
abundances for each spectrum. The mean atmospheric parameters and the
mean abundances computed for each star together with the estimated
uncertainties and the number of spectra used are also presented.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 67 20 Sample of 20 calibrating Cepheids with
high-resolution spectra covering either a
substantial portion or the entire pulsation cycle
table9.dat 196 20 Abundances of alpha elements for each star
table8.dat 201 432 Abundances of alpha elements for each spectrum
table4.dat 103 503 Atmospheric parameters, Fe abundances, and
radial velocities for each spectrum
table2.dat 40 521 Atomic parameters of Fe I and Fe II lines
table3.dat 40 129 Atomic parameters of alpha-element lines
refs.dat 172 35 References
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See also:
J/A+A/616/A82 : Physical parameters of classical Cepheids (Proxauf+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Name
11- 12 I2 h RAh Right ascension (ICRS)
14- 15 I2 min RAm Right ascension (ICRS)
17- 22 F6.3 s RAs Right ascension (ICRS)
24 A1 --- DE- Declination sign (ICRS)
25- 26 I2 deg DEd Declination (ICRS)
28- 29 I2 arcmin DEm Declination (ICRS)
31- 36 F6.3 arcsec DEs Declination (ICRS)
38- 39 A2 --- Mode Pulsation mode (1)
41- 45 F5.2 [-] [Fe/H]lit Iron abundance from literature
47- 50 F4.2 [-] e_[Fe/H]lit Iron abundance from literature error
52 I1 --- r_[Fe/H]lit Reference for [Fe/H]lit (2)
54- 55 I2 --- NF ?=- Number of optical spectra used for
spectrograph FEROS
57- 58 I2 --- NH ?=- Number of optical spectra used for
spectrograph HARPS
60 I1 --- NU ?=- Number of optical spectra used for
spectrograph UVES
62- 63 I2 --- NS ?=- Number of optical spectra used for
spectrograph STELLA.
65- 67 I3 --- Ntot Total number of spectra per target
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Note (1): Pulsation mode as follows:
0 = fundamental
1 = first overtone
0B = fundamental with bump
Note (2): References as follows:
1 = Genovali et al. (2014A&A...566A..37G 2014A&A...566A..37G, Cat. J/A+A/566/A37);
for TVul, FF Aql, Cep, and S Sge we assumed a typical error of 0.1dex
since they were not provided by the original authors
2 = Proxauf et al. (2018A&A...616A..82P 2018A&A...616A..82P, Cat. J/A+A/616/A82), from which the
uncertainty adopted is the largest value between σ and std
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Cepheid name
12- 16 F5.2 --- [Mg/H] Mean Magnesium abundance from MgI lines
19- 22 F4.2 --- e_[Mg/H] Error in the mean Mg abundance
25- 28 F4.2 --- s_[Mg/H] Standard deviation of the mean Mg abundance
31- 33 I3 --- o_Mg Number of spectra used for Mg lines
36- 39 F4.2 --- [SiI/H] Mean Silicon abundance from SiI lines
42- 45 F4.2 --- e_[SiI/H] Error in the mean SiI abundance
48- 51 F4.2 --- [SiII/H] ? Mean Silicon abundance from SiII lines
54- 57 F4.2 --- e_[SiII/H] ? Error in the mean SiII abundance
60- 63 F4.2 --- [Si/H] Mean Silicon abundance from SiI,SiII lines
66- 69 F4.2 --- e_[Si/H] Error in the mean Si abundance
72- 75 F4.2 --- s_[Si/H] Standard deviation of the mean Si abundance
78- 80 I3 --- o_Si Number of spectra used for Si lines
83- 87 F5.2 --- [SI/H] ? Mean Sulfur abundance from SI lines
90- 93 F4.2 --- e_[SI/H] ? Error in the mean S abundance
96 I1 --- o_SI ? Number of spectra used for S lines
99-103 F5.2 --- [CaI/H] Mean Calcium abundance from CaI lines
106-109 F4.2 --- e_[CaI/H] Error in the mean CaI abundance
112-116 F5.2 --- [CaII/H] ? Mean Calcium abundance from CaII lines
119-122 F4.2 --- e_[CaII/H] ? Error in the mean CaII abundance
125-129 F5.2 --- [Ca/H] Mean Calcium abundance from CaI,CaII lines
132-135 F4.2 --- e_[Ca/H] Error in the mean Ca abundance
138-141 F4.2 --- s_[Ca/H] Standard deviation of the mean Ca abundance
144-146 I3 --- o_Ca Number of spectra used for Ca lines
149-153 F5.2 --- [TiI/H] Mean Titanium abundance from TiI lines
156-159 F4.2 --- e_[TiI/H] Error in the mean TiI abundance
162-166 F5.2 --- [TiII/H] Mean Titanium abundance from TiII lines
169-172 F4.2 --- e_[TiII/H] Error in the mean TiII abundance
175-179 F5.2 --- [Ti/H] Mean Titanium abundance from TiI,TiII lines
182-185 F4.2 --- e_[Ti/H] Error in the mean Ti abundance
188-191 F4.2 --- s_[Ti/H] Standard deviation of the mean Ti abundance
194-196 I3 --- o_Ti Number of spectra used for Ti lines
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Cepheid name
12- 17 A6 --- Dataset Spectroscopic dataset
20- 32 F13.7 d MJD Modified Julian Date
35- 39 F5.2 --- [MgI/H] ? Magnesium abundance from MgI lines
42- 45 F4.2 --- e_[MgI/H] ? Error in the MgI abundance
48 I1 --- o_MgI ? Number of MgI lines adopted
51- 55 F5.2 --- [SiI/H] Silicon abundance from SiI lines
58- 61 F4.2 --- e_[SiI/H] Error in the SiI abundance
64 I1 --- o_SiI Number of SiI lines adopted
67- 71 F5.2 --- [SiII/H] ? Silicon abundance from SiII lines
74- 77 F4.2 --- e_[SiII/H] ? Error in the SiII abundance
80 I1 --- o_SiII ? Number of SiII lines adopted
83- 87 F5.2 --- [Si/H] Silicon abundance from SiI,SiII lines
90- 93 F4.2 --- e_[Si/H] Error in the Si abundance
96-100 F5.2 --- [SI/H] ? Sulfur abundance from SI lines
103-106 F4.2 --- e_[SI/H] ? Error in the SI abundance
109 I1 --- o_SI ? Number of SI lines adopted
112-116 F5.2 --- [CaI/H] ? Calcium abundance from CaI lines
119-122 F4.2 --- e_[CaI/H] ? Error in the CaI abundance
125-126 I2 --- o_CaI ? Number of CaI lines adopted
129-133 F5.2 --- [CaII/H] ? Calcium abundance from CaII lines
136-139 F4.2 --- e_[CaII/H] ? Error in the CaII abundance
142 I1 --- o_CaII ? Number of CaII lines adopted
145-149 F5.2 --- [Ca/H] ? Calcium abundance from CaI,CaII lines
152-155 F4.2 --- e_[Ca/H] ? Error in the Ca abundance
158-162 F5.2 --- [TiI/H] Titanium abundance from TiI lines
165-168 F4.2 --- e_[TiI/H] Error in the TiI abundance
171-172 I2 --- o_TiI Number of TiI lines adopted
175-179 F5.2 --- [TiII/H] ? Titanium abundance from TiII lines
182-185 F4.2 --- e_[TiII/H] ? Error in the TiII abundance
188 I1 --- o_TiII ? Number of TiII lines adopted
191-195 F5.2 --- [Ti/H] Titanium abundance from TiI,TiII lines
198-201 F4.2 --- e_[Ti/H] Error in the Ti abundance
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Cepheid name
12- 17 A6 --- Dataset Spectroscopic dataset
20- 32 F13.7 d MJD Modified Julian Date
35- 38 I4 K Teff ? Effective temperature
41- 43 I3 K e_Teff ? Error in the effective temperature
46- 48 F3.1 [cm/s2] logg ? Surface gravity
51- 53 F3.1 km/s vt ? Microturbulent velocity
56- 60 F5.2 --- [FeI/H] ? Iron abundance from FeI lines
63- 66 F4.2 --- e_[FeI/H] ? Error in the FeI abundance
69- 71 I3 --- o_[FeI/H] ? Number of FeI lines adopted
74- 78 F5.2 --- [FeII/H] ? Iron abundance from FeII lines
81- 84 F4.2 --- e_[FeII/H] ? Error in the FeII abundance
87- 88 I2 --- o_[FeII/H] ? Number of FeII lines adopted
91- 97 F7.2 km/s RV Radial velocity
100-103 F4.2 km/s e_RV Error in the radial velocity
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Byte-by-byte Description of file: table2.dat table3.dat
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Bytes Format Units Label Explanations
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1- 9 F9.3 0.1nm lambda Wavelength of the atomic line
12- 16 A5 --- Species Atomic species
19- 23 F5.3 eV xi Lower-level excitation potential
26- 31 F6.3 --- log(gf) Logarithmic weighted oscillator strength
34 I1 --- Qflag Quality flag indicating if a line is used
37- 40 A4 --- Refs Reference(s) for the atomic parameters,
in refs.dat file
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode BibCode
24- 45 A22 --- Aut Author's name
46-172 A127 --- Com Comments
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Acknowledgements:
Ronaldo Oliveira, ronaldo.oliveira(at)inaf.it
References:
Proxauf et al., Paper I 2018A&A...616A..82P 2018A&A...616A..82P, Cat. J/A+A/616/A82
(End) Patricia Vannier [CDS] 24-Feb-2022