J/AJ/106/2096Limb-darkening coefficients in binaries (Van Hamme 1993)

New limb-darkening coefficients for modeling binary star light curves VAN HAMME W. <Astron. J. 106, 2096 (1993)> =1993AJ....106.2096VADC_Keywords: Binaries, eclipsing; Models, atmosphereAbstract: We present monochromatic, passband-specific, and bolometric limb-darkening coefficients for a linear as well as nonlinear logarithmic and square root limb-darkening laws. These coefficients, including the bolometric ones, are needed when modeling binary star light curves with the latest version of the Wilson-Devinney light curve program. We base our calculations on the most recent ATLAS stellar atmosphere models for solar chemical composition stars with a wide range of effective temperatures and surface gravities. We examine how well various limb-darkening approximations represent the variation of the emerging specific intensity across a stellar surface as computed according to the model. For binary star light curve modeling purposes, we propose the use of a logarithmic or a square root law. We design our tables in such a manner that the relative quality of either law with respect to another can be easily compared. Since the computation of bolometric limb-darkening coefficients first requires monochromatic coefficients, we also offer tables of these coefficients (at 1221 wavelength values between 0.09 nm and 160 µm) and tables of passband-specific coefficients for commonly used photometric filters.File Summary:

FileName Lrecl Records Explanations

ReadMe 80 . This file table1 79 410 Bolometric limb-darkening coefficients table2 87 6970 Passband-specific limb-darkening coefficients table3a 29 410 Models parameters table3b 79 410 Bolometric coefficients table3c 79 466367 Monochromatic coefficients

Byte-by-byte Description of file: table1

Bytes Format Units Label Explanations

1- 3 I3 --- Model Model number 4- 9 I6 K Teff Effective temperature 10- 14 F5.1 [cm/s2] log(g) Logarithm of the surface gravity 15- 22 F8.3 --- xBol Bolometric linear limb-darkening coefficient x 25- 30 F6.4 --- QBol Quality factor (1) 32- 39 F8.3 --- xLog Logarithmic law x coefficient 40- 46 F7.3 --- yLog Logarithmic law y coefficient 49- 54 F6.4 --- QLog Quality factor (1) 56- 63 F8.3 --- xSqu Square root law x coefficient 64- 70 F7.3 --- ySqu Square root law y coefficient 73- 78 F6.4 --- QSqu Quality factor (1)

Note (1): see below on table3b

Byte-by-byte Description of file: table2

Bytes Format Units Label Explanations

1- 3 I3 --- Model Model number 4- 9 I6 K Teff Effective temperature 10- 14 F5.1 [cm/s2] log(g) Logarithm of the surface gravity 17- 20 A4 --- Pass Passband (2) 24- 28 F5.3 --- xLin Linear limb-darkening coefficient 31- 36 F6.4 --- QLin Quality factor (1) 42- 46 F5.3 --- xLog Logarithmic law x coefficient 48- 53 F6.3 --- yLog Logarithmic law y coefficient 56- 61 F6.4 --- QLog Quality factor (1) 66- 71 F6.3 --- xSqu Square root law x coefficient 73- 78 F6.3 --- ySqu Square root law y coefficient 81- 86 F6.4 --- QSqu Quality factor (1)

Note (1): see below on table3bNote (2): The passbands are: Johnson : UBVRIJKLMN Cousins : Ic Rc Stroemgren : uvby bolo = bolometric

Byte-by-byte Description of file: table3a

Bytes Format Units Label Explanations

1- 3 I3 --- Model Model number 6- 10 I5 K Teff Effective temperature 12- 14 F3.1 [cm/s2] log(g) Logarithm of the surface gravity 16- 19 F4.2 Sun A Abundance (always solar abundance) 22- 24 F3.1 km/s Vturb Microturbulent velocity 26- 29 F4.2 --- l/H []? Convective parameter

Byte-by-byte Description of file: table3b table3c

Bytes Format Units Label Explanations

1- 3 I3 --- Model Model number 5- 15 F11.2 nm lambda []? Wavelength 17- 21 F5.3 --- xBol Linear limb-darkening coefficient 23- 28 F6.4 --- QBol Quality factor (1) 30- 34 F5.3 --- xLog Logarithmic law x coefficient 36- 41 F6.3 --- yLog Logarithmic law y coefficient 43- 48 F6.4 --- QLog Quality factor (1) 50- 55 F6.3 --- xSqu Square root law x coefficient 57- 62 F6.3 --- ySqu Square root law y coefficient 64- 69 F6.4 --- QSqu Quality factor (1) 71- 79 E9.3 mW/m2/sr/nm I ? Intensity, I(lambda, mu=1)

Note (1): Quality factor Q defined as (all parameters refer to monochromatic values): Q={sum(for i=1 to 17)[D(mu_{i})-D'(mu_{i})]/(17-m)}1/2 where D(mu) = I(mu)/I(1) D'(mu) = I'(mu)/I'(1) and I(mu) is the theoretical specific intensity I'(mu) is the specific intensity according to the limb-darkening approximation This number may help in choosing which limb-darkening law to use in any particular case

Origin: AAS CD-ROM series, Volume 1, 1993(End)Patricia Bauer [CDS] 30-Jun-1994

The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line |

catalogue service

© UDS/CNRS