J/MNRAS/456/1294 Limb-darkening coefficients (Reeve+, 2016)
Limb-darkening coefficients from line-blanketed non-LTE hot-star model
atmospheres.
Reeve D.C., Howarth I.D.
<Mon. Not. R. Astron. Soc. 456, 1294 (2016)>
=2016MNRAS.456.1294R 2016MNRAS.456.1294R (SIMBAD/NED BibCode)
ADC_Keywords: Models, atmosphere
Keywords: radiative transfer - stars: atmospheres
Abstract:
We present grids of limb-darkening coefficients computed from
non-LTE, line-blanketed TLUSTY model atmospheres, covering
effective-temperature and surface-gravity ranges of 15-55kK and
4.75dex (cgs) down to the effective Eddington limit, at 2x, 1x, 0.5x
(Large Magellanic Cloud), 0.2x (Small Magellanic Cloud), and 0.1x
solar. Results are given for the Bessell UBVRICJKHL, Sloan ugriz,
Stromgren ubvy, WFCAM ZYJHK , Hipparcos, Kepler, and Tycho passbands,
in each case characterized by several different limb-darkening 'laws'.
We examine the sensitivity of limb darkening to temperature, gravity,
metallicity, microturbulent velocity, and wavelength, and make a
comparison with LTE models. The dependence on metallicity is very
weak, but limb darkening is a moderately strong function of logg in
this temperature regime.
Description:
Detailed limb-darkening coefficients for individual stellar models, as
described in the paper.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
summary1.dat 245 35119 All linear and quadratic limb-darkening LDCs
in condensed form
summary2.dat 172 35119 'Claret' 4-parameter LDCs in condensed form
models/* . 1211 *Individual model files
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Note on models/*: Each file contains a series of blocks.
In each block, the first line lists
- the passband identifier
- the effective wavelength (in angstroms)
- the broad-band physical flux Flambda
(=4πHlambda, in erg/cm2/s/Å);
- the broad-band surface-normal intensity Ilambda(1)
(in erg/cm2/s/Å/sr)
Subsequent lines list coefficients for the limb-darkening laws
discussed in the paper
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Byte-by-byte Description of file (#) : summary1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- FileName Name of individual-model source file (G1)
16- 27 A12 --- Filter Identifies filter passband (G2)
29- 40 E12.6 10mW/m2/nm/sr I(1) Surface-normal intensity in passband
(in erg/cm2/s/Å/sr)
42- 53 E12.6 --- lin1.1 I(1,fit)/I(1,model) for
least-squares linear fit 1
55- 66 E12.6 --- lin1.2 linear LDC 'u' for linear fit 1
68- 81 E14.6 --- lin2.1 I(1,fit)/I(1,model) for
least-squares linear fit 2
83- 94 E12.6 --- lin2.2 linear LDC 'u' for linear fit 2
96-109 E14.6 --- linF.1 I(1,fit)/I(1,model) for
flux-conserving linear fit
111-122 E12.6 --- linF.2 linear LDC 'u' for
flux-conserving linear fit
124-137 E14.6 --- quad2.1 I(1,fit)/I(1,model) for
least-squares quadratic fit 1
139-150 E12.6 --- quad2.2 quadratic LDC u1 for
least-squares quadratic fit 1
152-163 E12.6 --- quad2.3 quadratic LDC u2 for
least-squares quadratic fit 1
165-178 E14.6 --- quad3.1 I(1,fit)/I(1,model) for
least-squares quadratic fit 2
180-191 E12.6 --- quad3.2 quadratic LDC u1 for
least-squares quadratic fit 2
193-204 E12.6 --- quad3.3 quadratic LDC u2 for
least-squares quadratic fit 2
206-219 E14.6 --- quadF.1 I(1,fit)/I(1,model) for
flux-conserving quadratic fit
221-232 E12.6 --- quadF.2 quadratic LDC u1 for
flux-conserving quadratic fit
234-245 E12.6 --- quadF.3 quadratic LDC u2 for
flux-conserving quadratic fit
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Byte-by-byte Description of file (#): summary2.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- FileName Name of individual-model source file (G1)
16- 27 A12 --- Filter Identifies filter passband (G2)
29- 40 E12.6 10mW/m2/nm/sr I(1) Surface-normal intensity in passband
(in erg/cm2/s/Å/sr)
42- 53 E12.6 --- a1.0 I(1,fit)/I(1,model) for
least-squares 4-coefficient fit 1
55- 66 E12.6 --- a1.1 a1 coefficient for
least-squares 4-coefficient fit 1
68- 79 E12.6 --- a1.2 a2 coefficient for
least-squares 4-coefficient fit 1
81- 92 E12.6 --- a1.3 a3 coefficient for
least-squares 4-coefficient fit 1
94-105 E12.6 --- a1.4 a4 coefficient for
least-squares 4-coefficient fit 1
109-120 E12.6 --- a2.0 I(1,fit)/I(1,model) for
least-squares 4-coefficient fit 2
122-133 E12.6 --- a2.1 a1 coefficient for
least-squares 4-coefficient fit 2
135-146 E12.6 --- a2.2 a2 coefficient for
least-squares 4-coefficient fit 2
148-159 E12.6 --- a2.3 a3 coefficient for
least-squares 4-coefficient fit 2
161-172 E12.6 --- a2.4 a4 coefficient for
least-squares 4-coefficient fit 2
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Byte-by-byte Description of file (#): models/*
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Bytes Format Units Label Explanations
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3- 13 A11 --- Param Parameter (1)
17- 29 E13.5 --- If/Im Ratio of the fitted surface-normal intensity
to the model-atmosphere value,
I(1,fit)/I(1,model) (1)
30- 42 E13.5 --- Coeff1 First limb-darkening coefficient
43- 55 E13.5 --- Coeff2 ? Second limb-darkening coefficient
56- 68 E13.5 --- Coeff3 ? Third limb-darkening coefficient
69- 81 E13.5 --- Coeff4 ? Fourth limb-darkening coefficient
86- 95 E10.4 --- fitQual Fit quality (being the r.m.s.)
97-106 E10.4 --- O-Cmax Maximum O-C value of
Ilambda(mu)/Ilambda(1) (2)
109-112 F4.2 --- mu Value of mu for which the absolute value of
the mismatch is greatest
117-122 F6.3 --- Perr Percentage error in the flux (3)
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Note (1): List of parameters:
linear - 1, linear - 2, lin - FCLS, quad - 2, quad - 3, quad - FCLS, 1+4-coeff
and 4-coeff
Note (2): where O and C refer to model-atmosphere and analytical-fit values.
Note (3): Percentage error in the flux obtained by integrating the analytical
representation of the intensity to obtain the first moment of the radiation
field (Eddington flux, Hlambda=Flambda/4π).
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Global notes:
Note (G1): in the form SAtttttgGGGvVV, encoding model details;
-S is spectral-type regime ('O' or 'B')
-A is abundance code ('G' for 'Galactic', etc.; see Table 1 below)
-ttttt is the model effective temperature (K)
-GGG is 100 times the surface gravity (dex cgs)
-VV is the turbulent velocity (km/s)
Table 1: Summary of models:
----------------------------------------------------------------------------
Grid Teff logg (min) (max) vt Z/Z_☉ coding N
(kK) [Teff(lo) Teff(hi)] (km/s)
----------------------------------------------------------------------------
OStar02 27.5-55.0 3.00 4.00 4.75 10 2 1 0.5 0.2 0.1 345
BStar06 15.0-30.0 1.75 3.00 4.75 2 C G L S T 817
BStar06 15.0-30.0 1.75 3.00 3.00 10 G 49
----------------------------------------------------------------------------
with metallicity codings identified in columns 7-11 (e.g.,
the L grid corresponds to Z=Z☉=0.5);
vt the microturbulence and N N the number of models
Note (G2): List of passbands:
Bessell-UX , Bessell-BX, Bessell-B, Bessell-V, Bessell-R, Bessell-I,
Bessell-J, Bessell-H, Bessell-K, Bessell-L Bessell-Lp
Sloan-u, Sloan-g, Sloan-r, Sloan-i, Sloan-z
Stromgren-u, Stromgren-v, Stromgren-b, Stromgren-y
Kepler, WFCAM-Z, WFCAM-Y, WFCAM-J, WFCAM-H, WFCAM-K
Hipparcos-Hp, Tycho-BT, Tycho-VT
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Acknowledgements:
Ian Howarth, i.howarth(at)ucl.ac.uk
(End) Ian Howarth [UCL], Patricia Vannier [CDS] 07-Dec-2015