J/AJ/117/981 Estimation of stellar metal abundance. II. (Beers+, 1999)
Estimation of stellar metal abundance. II. A recalibration of the Ca II K
technique, and the autocorrelation function method.
Beers T.C., Rossi S., Norris J.E., Ryan S.G., Shefler T.
<Astron. J. 117, 981 (1999)>
=1999AJ....117..981B 1999AJ....117..981B
ADC_Keywords: Abundances, [Fe/H] ; Radial velocities ; Photometry
Keywords: Galaxy: abundances - Galaxy: halo - stars: Population II
Abstract:
We have recalibrated a method for the estimation of stellar metal
abundance, parameterized as [Fe/H], based on medium-resolution
(1-2Å) optical spectra (the majority of which cover the wavelength
range 3700-4500Å). The equivalent width of the Ca II K line
(3933Å) as a function of [Fe/H] and broadband B-V color, as
predicted from spectrum synthesis and model atmosphere calculations,
is compared with observations of 551 stars with high-resolution
abundances available from the literature (a sevenfold increase in the
number of calibration stars that were previously available). A second
method, based on the Fourier autocorrelation function technique first
described by Ratnatunga & Freeman (1989, Cat. V/65), is used to
provide an independent estimate of [Fe/H], as calibrated by comparison
with 405 standard-star abundances.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 141 551 Observed quantities for program stars
table6.dat 147 551 Derived quantities for program stars
refs.dat 139 24 References to table6.dat
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See also:
J/AJ/107/1577 : Halo red giants reddening (Anthony-Twarog+, 1994)
J/AJ/115/168 : Kinematics of red giant and RR Lyrae stars (Chiba+ 1998)
V/65 : Spectroscopically Selected Halo K Giants (Ratnatunga+ 1989)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Star Star name
18- 27 A10 --- HD HD (Cat. III/135) designation
29- 40 A12 --- DM Durchmustering; BD (Cat. I/122), CD (I/114)
or CPD (I/108) designation
42- 49 A8 --- G Giclas (Cat. I/79) designation
51- 55 F5.2 mag Vmag V magnitude
57- 60 F4.2 mag B-V B-V colour index
62- 65 F4.2 mag E(B-V) Reddening
67- 70 F4.2 mag (B-V)0 Dereddened B-V colour index
72- 75 F4.2 mag (B-V)HP2 ? Estimated broadband B-V color obtained from
the calibrated Balmer-line indices HP2
77- 80 F4.2 mag (B-V)H8 ? Estimated broadband B-V color obtained from
the calibrated Balmer-line indices H8
83- 86 I4 km/s RV Radial velocity
87 A1 --- n_RV [*] *: Radial velocity from Ryan & Norris
(1991AJ....101.1835R 1991AJ....101.1835R)
89- 92 F4.2 0.1nm H8 ? Balmer-line index H8 (3889Å)
94- 98 F5.2 0.1nm KP Ca II K index KP
100-103 F4.2 0.1nm HP2 ? Balmer-line index HP2
105-109 F5.2 0.1nm LACF ? Metallicity index log ACF
111-141 A31 --- Tel Telescope code (1)
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Note (1): contents of table5:
Observational setups for intermediate-resolution spectroscopy
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Code Telescope Detector Grating Coverage Dispersion
lines/mm 0.1nm 0.1nm/pix
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A1 Mount Stromlo Obs. 1.9 m PCA Coude 3750-4100 0.4
A2 Siding Spring Obs. 2.3 m PCA 1200 3800-4300 0.5
A3 Siding Spring Obs. 2.3 m Loral 1024x1024 1200 3800-4400 0.5
A4 Siding Spring Obs. 2.3 m SITe 1752x532 1200 3750-4600 0.5
BL Las Campanas 2.5 m Reticon 1200 3700-4500 0.3 (0.65)
BL Paper I 2D-FRUTTI 1200 3700-4500 0.6 (0.65)
BP Palomar 5 m Reticon 1200 3700-4500 0.3 (0.65)
BP Paper I 2D-FRUTTI 1200 3700-4500 0.6 (0.65)
E1 European Southern Obs. 1.5m Ford 2048x2048 900 3750-4750 0.65
E2 European Southern Obs. 1.5m Loral 2048x2048 HOLO 3750-4600 0.5
KP Kitt Peak National Obs. 2.1m Tek 2048x2048 600 3750-5000 0.65
I Isaac Newton 2.5m Tek 1024x1024 1200 3750-4700 0.9
L Lowell Obs. 1.8m Tek 512x512 900 4000-4250 1.0
O Obs.Haute-Provence 1.9m Tek 512x512 1200 3750-4250 0.9
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Note : In dispersion column, rebinned spectra are in parentheses.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Star Star designation
19- 21 A3 --- Class Star classification (1)
22 A1 --- n_Class [abc] Note (2)
24- 28 F5.2 mag VMAG Absolute V magnitude
29 A1 --- u_VMAG Uncertainty flag on VMAG
31- 34 I4 pc Dist ? Distance
35 A1 -- u_Dist Uncertainty flag on Dist
37- 41 F5.2 [Sun] [Fe/H]0 Adopted standard abundance
43- 60 A18 ---- r_Star Comma-separated references in file refs.dat
62- 66 F5.2 [Sun] [Fe/H]K1 Estimated abundance based on KP index
68- 72 F5.2 [Sun] [Fe/H]A1 ? Fisrt-pass estimated abundance
based on LACF index
74- 78 F5.2 [Sun] [Fe/H]K2 Fisrt-pass estimated abundance
based on KP index
80- 83 F4.2 [Sun] e_[Fe/H]K2 rms uncertainty on [Fe/H]K2
85- 89 F5.2 [Sun] [Fe/H]A2 ? Second-pass estimated abundance
based on LACF index
91- 94 F4.2 [Sun] e_[Fe/H]A2 ? rms uncertainty on [Fe/H]A2
96-100 F5.2 [Sun] [Fe/H]AK1 Joint abundance estimate (KP and LACF)
102-106 F5.2 [Sun] resAK1 Resulting residual ([Fe/H]AK1-[Fe/H]0)
108-112 F5.2 [Sun] [Fe/H]K3 Third-pass estimated abundance
based on KP index (3)
114-117 F4.2 [Sun] e_[Fe/H]K3 rms uncertainty on [Fe/H]K3
119-123 F5.2 [Sun] [Fe/H]A3 ? Third-pass estimated abundance
based on LACF index
125-128 F4.2 [Sun] e_[Fe/H]A3 ? rms uncertainty on [Fe/H]A3
130-134 F5.2 [Sun] [Fe/H]AK2 ? Final abundance estimate
136-139 F4.2 [Sun] e_[Fe/H]AK2 ? rms uncertainty on [Fe/H]AK2
141-145 F5.2 [Sun] resAK2 Resulting residual ([Fe/H]AK2-[Fe/H]0)
146-147 A2 --- n_resAK2 [def] Note (4)
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Note (1): Classification:
AGB: Asymptotic giant branch
D: dwarf
G: giant
HB: horizontal branch
SG: supergiant
TO: main-sequence turnoff
Note (2): the symbols are:
a: Colors too blue for 15 Gyr isochrone; see text
b: Colors too red for 15 Gyr isochrone; see text
c: Near or beyond main-sequence terminus; see text
Note (3): [Fe/H]K3 = [Fe/H]K2 - RES2p, where RES2p is the predicted residual
obtained from the above fit
Note (4): the symbols are:
d: Colors outside nominal calibration region; see text
e: |K3- A3|>+0.5dex; see text
f: |resAK2|>3.0σ; see text
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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- 51 A28 --- Aut Author names
53-142 A90 --- Com Comments
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History:
* 19-Apr-1999: From AJ electronic version
In Table 4 : NGC 6297 717 misprint of 6397 717.
"BS" replaced by "BPS"
References:
Beers et al., Paper I. 1990AJ....100..849B 1990AJ....100..849B
(End) James Marcout, Patricia Bauer [CDS] 19-Apr-1999