Access to Astronomical Catalogues

← Click to display the menu
J/A+A/611/A68       3D correction in 5 photometric systems    (Bonifacio+, 2018)

Using the CIFIST grid of CO5BOLD 3D model atmospheres to study the effects of stellar granulation on photometric colours. I. Grids of 3D corrections in the UBVRI, 2MASS, Hipparcos, Gaia, and SDDS systems. Bonifacio P., Caffau E., Ludwig H.-G., Steffen M.,Castelli F., Gallagher A.J., Kucinskas A., Prakapavicius D., Cayrel R., Freytag B., Plez B., Homeier D. <Astron. Astrophys. 611, A68 (2018)> =2018A&A...611A..53B
ADC_Keywords: Stars, atmospheres ; Effective temperatures ; Colors ; Models Keywords: hydrodynamics - radiative transfer - methods: numerical - techniques: photometric - stars: atmospheres Abstract: The atmospheres of cool stars are temporally and spatially inhomogeneous due to the effects of convection. The influence of this inhomogeneity, referred to as granulation, on colours has never been investigated over a large range of effective temperatures and gravities. We aim to study, in a quantitative way, the impact of granulation on colours. We use the CIFIST (Cosmological Impact of the FIrst Stars) grid of CO5BOLD (COnservative COde for the COmputation of COmpressible COnvection in a BOx of L Dimensions, L=2,3) hydrodynamical models to compute emerging fluxes. These in turn are used to compute theoretical colours in the UBVRI, 2MASS, Hipparcos, Gaia and SDSS systems. Every CO5BOLD model has a corresponding one dimensional (1D) plane-parallel LHD (Lagrangian HydroDynamics) model computed for the same atmospheric parameters, which we used to define a "3D correction" that can be applied to colours computed from fluxes computed from any 1D model atmosphere code. As an example, we illustrate these corrections applied to colours computed from ATLAS models. The 3D corrections on colours are generally small, of the order of a few hundredths of a magnitude, yet they are far from negligible. We find that ignoring granulation effects can lead to underestimation of Teff by up to 200K and overestimation of gravity by up to 0.5dex, when using colours as diagnostics.We have identified a major shortcoming in how scattering is treated in the current version of the CIFIST grid, which could lead to offsets of the order 0.01mag, especially for colours involving blue and UV bands. We have investigated the Gaia and Hipparcos photometric systems and found that the (G-Hp),(BP-RP) diagram is immune to the effects of granulation. In addition, we point to the potential of the RVS photometry as a metallicity diagnostic. Our investigation shows that the effects of granulation should not be neglected if one wants to use colours as diagnostics of the stellar parameters of F,G,K stars. A limitation is that scattering is treated as true absorption in our current computations, thus our 3D corrections are likely an upper limit to the true effect. We are already computing the next generation of the CIFIST grid, using an approximate treatment of scattering. Description: We have used the CIFIST grid of CO5BOLD models to investigate the effects of granulation on fluxes and colours of stars of spectral type F, G, and K. We publish tables with 3D corrections that can be applied to colours computed from any 1D model atmosphere. For Teff≥5000K, the corrections are smooth enough, as a function of atmospheric parameters, that it is possible to interpolate the corrections between grid points; thus the coarseness of the CIFIST grid should not be a major limitation. However at the cool end there are still far too few models to allow a reliable interpolation. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tablea1.dat 93 27 Colours and corrections for the Johnson-Cousins system for metallicity [M/H]=0.0 tablea2.dat 93 26 Colours and corrections for the Johnson-Cousins system for metallicity [M/H]=-1.0 tablea3.dat 93 27 Colours and corrections for the Johnson-Cousins system for metallicity [M/H]=-2.0 tablea4.dat 93 27 Colours and corrections for the Johnson-Cousins system for metallicity [M/H]=-3.0 tablea5.dat 93 27 Colours and corrections for the 2MASS and Hipparcos-Tycho systems for metallicity [M/H]=0.0 tablea6.dat 93 26 Colours and corrections for the 2MASS and Hipparcos-Tycho systems for metallicity [M/H]=-1.0 tablea7.dat 93 27 Colours and corrections for the 2MASS and Hipparcos-Tycho systems for metallicity [M/H]=-2.0 tablea8.dat 93 26 Colours and corrections for the 2MASS and Hipparcos-Tycho systems for metallicity [M/H]=-3.0 tablea9.dat 93 27 Colours and corrections for the Gaia system for metallicity [M/H]=0.0 tablea10.dat 93 26 Colours and corrections for the Gaia system for metallicity [M/H]=-1.0 tablea11.dat 93 27 Colours and corrections for the Gaia system for metallicity [M/H]=-2.0 tablea12.dat 93 27 Colours and corrections for the Gaia system for metallicity [M/H]=-3.0 tablea13.dat 93 27 Colours and corrections for SDSS u-g, g-z, g-r and g-i for metallicity [M/H]=0.0 tablea14.dat 93 26 Colours and corrections for SDSS u-g, g-z, g-r and g-i for metallicity [M/H]=-1.0 tablea15.dat 93 27 Colours and corrections for SDSS u-g, g-z, g-r and g-i for metallicity [M/H]=-2.0 tablea16.dat 93 27 Colours and corrections for SDSS u-g, g-z, g-r and g-i for metallicity [M/H]=-3.0 tablea17.dat 93 27 Colours and corrections for SDSS r-i, i-z, u-i and u-z for metallicity [M/H]=0.0 tablea18.dat 93 26 Colours and corrections for SDSS r-i, i-z, u-i and u-z for metallicity [M/H]=-1.0 tablea19.dat 93 27 Colours and corrections for SDSS r-i, i-z, u-i and u-z for metallicity [M/H]=-2.0 tablea20.dat 93 27 Colours and corrections for SDSS r-i, i-z, u-i and u-z for metallicity [M/H]=-3.0
Byte-by-byte Description of file: tablea[1234].dat
Bytes Format Units Label Explanations
1- 4 I4 K Teff Effective temperature 6- 9 F4.2 [cm/s2] logg Surface gravity 11- 16 F6.3 mag U-BA ATLAS U-B colour correction 18- 23 F6.3 mag U-BAc ATLAS U-B colour correction with 3D correction added to the ATLAS colour 25- 30 F6.3 mag dU-B U-B correction difference, U-BA - U-BAc 32- 37 F6.3 mag B-VA ATLAS B-V colour correction 39- 44 F6.3 mag B-VAc ATLAS B-V colour correction with 3D correction added to the ATLAS colour 46- 51 F6.3 mag dB-V B-V correction difference, B-VA - B-VAc 53- 58 F6.3 mag V-RA ATLAS V-R colour correction 60- 65 F6.3 mag V-RAc ATLAS V-R colour correction with 3D correction added to the ATLAS colour 67- 72 F6.3 mag dV-R V-R correction difference, V-RA - V-RAc 74- 79 F6.3 mag V-IA ATLAS V-I colour correction 81- 86 F6.3 mag V-IAc ATLAS V-I colour correction with 3D correction added to the ATLAS colour 88- 93 F6.3 mag dV-I V-I correction difference, V-IA - V-IAc
Byte-by-byte Description of file: tablea[5678].dat
Bytes Format Units Label Explanations
1- 4 I4 K Teff Effective temperature 6- 9 F4.2 [cm/s2] logg Surface gravity 11- 16 F6.3 mag J-KA ATLAS J-K colour correction 18- 23 F6.3 mag J-KAc ATLAS J-K colour correction with 3D correction added to the ATLAS colour 25- 30 F6.3 mag dJ-K J-K correction difference, J-KA - J-KAc 32- 37 F6.3 mag V-KA ATLAS V-K colour correction 39- 44 F6.3 mag V-KAc ATLAS V-K colour correction with 3D correction added to the ATLAS colour 46- 51 F6.3 mag dV-K B-K correction difference, V-KA - V-KAc 53- 58 F6.3 mag V-HpA ATLAS V-Hp colour correction 60- 65 F6.3 mag V-HpAc ATLAS V-Hp colour correction with 3D correction added to the ATLAS colour 67- 72 F6.3 mag dV-Hp V-Hp correction colour difference, V-HpA - V-HpAc 74- 79 F6.3 mag BT-VTA ATLAS BT-VT colour correction 81- 86 F6.3 mag BT-VTAc ATLAS BT-VT colour correction with 3D correction added to the ATLAS colour 88- 93 F6.3 mag dBT-VT BT-VT correction difference, BT-VTA - BT-VTAc
Byte-by-byte Description of file: tablea9.dat tablea1[012].dat
Bytes Format Units Label Explanations
1- 4 I4 K Teff Effective temperature 6- 9 F4.2 [cm/s2] logg Surface gravity 11- 16 F6.3 mag G-HpA ATLAS G-Hp colour correction 18- 23 F6.3 mag G-HpAc ATLAS G-Hp colour correction with 3D correction added to the ATLAS colour 25- 30 F6.3 mag dG-Hp G-Hp correction difference, G-HpA - G-HpAc 32- 37 F6.3 mag BP-RPA ATLAS BT-RP colour correction 39- 44 F6.3 mag BP-RPAc ATLAS BT-RP colour correction with 3D correction added to the ATLAS colour 46- 51 F6.3 mag dBP-RP BP-RP correction difference, BP-RPA - BP-RPAc 53- 58 F6.3 mag CaTA ATLAS CaT (=(G-RVS)-(BP-RP)) colour correction 60- 65 F6.3 mag CaTAc ATLAS CaT (=(G-RVS)-(BP-RP)) colour correction with 3D correction added to the ATLAS colour 67- 72 F6.3 mag dCaT CaT (=(G-RVS)-(BP-RP)) correction difference, CaTA - CaTAc 74- 79 F6.3 mag BolGA ATLAS bolometric correction 81- 86 F6.3 mag BolGAc ATLAS bolometric correction with 3D correction added to the ATLAS colour 88- 93 F6.3 mag dBolG Bolometric correction difference, BolGA - BolGAc
Byte-by-byte Description of file: tablea1[3456].dat
Bytes Format Units Label Explanations
1- 4 I4 K Teff Effective temperature 6- 9 F4.2 [cm/s2] logg Surface gravity 11- 16 F6.3 mag u-gA ATLAS u-g colour correction 18- 23 F6.3 mag u-gAc ATLAS u-g colour correction with 3D correction added to the ATLAS colour 25- 30 F6.3 mag du-g u-g correction difference, u-gA - u-gAc 32- 37 F6.3 mag g-zA ATLAS g-z colour correction 39- 44 F6.3 mag g-zAc ATLAS g-z colour correction with 3D correction added to the ATLAS colour 46- 51 F6.3 mag dg-z g-z correction difference, g-zA - g-zAc 53- 58 F6.3 mag g-rA ATLAS g-r colour correction 60- 65 F6.3 mag g-rAc ATLAS g-r colour correction with 3D correction added to the ATLAS colour 67- 72 F6.3 mag dg-r g-r correction difference, g-rA - g-rAc 74- 79 F6.3 mag g-iA ATLAS g-i colour correction 81- 86 F6.3 mag g-iAc ATLAS g-i colour correction with 3D correction been added to the ATLAS colour 88- 93 F6.3 mag dg-i g-i correction difference, g-iA - g-iAc
Byte-by-byte Description of file: tablea1[789].dat tablea20.dat
Bytes Format Units Label Explanations
1- 4 I4 K Teff Effective temperature 6- 9 F4.2 [cm/s2] logg Surface gravity 11- 16 F6.3 mag r-iA ATLAS r-i colour correction 18- 23 F6.3 mag r-iAc ATLAS r-i colour correction with 3D correction added to the ATLAS colour 25- 30 F6.3 mag dr-i r-i correction colour difference, r-iA - r-iAc 32- 37 F6.3 mag i-zA ATLAS i-z colour correction 39- 44 F6.3 mag i-zAc ATLAS i-z colour correction with 3D correction added to the ATLAS colour 46- 51 F6.3 mag di-z i-z correction colour difference, i-zA - i-zAc 53- 58 F6.3 mag u-iA ATLAS u-i colour correction 60- 65 F6.3 mag u-iAc ATLAS u-i colour correction with 3D correction added to the ATLAS colour 67- 72 F6.3 mag du-i u-i correction colour difference, u-iA - u-iAc 74- 79 F6.3 mag u-zA ATLAS u-z colour correction 81- 86 F6.3 mag u-zAc ATLAS u-z colour correction with 3D correction added to the ATLAS colour 88- 93 F6.3 mag du-z u-z correction difference, u-zA - u-zAc
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 25-Jan-2018
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

Contact