Input Data Files

All the data used by mcfost is generally read from the directory $MCFOST_UTILS. An additional environment variable MY_MCFOST_UTILS can be defined (giving the path to another directory) by the user to add her/his own data file. This has to advantage to ensure that no personal data file will be overwritten during an update.

When looking for data files, mcfost will first look in the local working directory, then in MY_MCFOST_UTILS if it is defined and finally in MCFOST_UTILS. If the data file used is in the local directory, it will be copied into the output directory as well.

The data directory also has a version number which correponds to the minimum MCFOST version which can use this data set (ie MCFOST version > MCFOST_UTILS version). MCFOST will ask the user to update the data directory if needed (note this also means that you won’t be able to use an old MCFOST version if the data directory is updated).

Dust Optical Constants

Filenames that are underlined in the following list indicate well-identified dust species (i.e., the origin of the file can be tracked in the literature with reasonable certainty). Comments at the top the files must start with a #.

The first line contains the material density in g/cm3 and the sublimation temperature. It is followed by an empty line and then 3 columns containing the wavelengths (in microns) and the real and imaginary parts of the optical indices. Wavelengths can be in ascending or descending order but must be ordered.

  • CO2_50K-reduit.dat: CO2 ice at 50K (origin?)

  • Draine_Si.dat "Astronomical silicates” from Bruce Draine (very similar though not exactly the same as those shown in Fig 3 of Draine & Lee 1984, ApJ, 285, 89 - use dlsi_opct.dat instead); file Draine_Si_sUV.dat is the version which has been smoothed in the UV.

  • Graphite_para.dat graphite with a “parallel” orientation (from Draine & Lee 1984, ApJ, 285, 89?)

  • Graphite_perp.dat graphite with a “perpendicular” orientation (from Draine & Lee 1984, ApJ, 285, 89?)

  • MW89.dat Highly porous composite interstellar grains. From Mathis and Whiffen 1989.

  • Olivine_modif.dat Amorphous MgFeSiO4 olivine. From Dorschner, Begemann, et al. 1995. A&A 300 503, see their Fig 5). File Olivine.dat contains the same optical indices but has no information for lambda > 500 micron, forcing the code to extrapolate. File Olivine_no_SI.dat contains the same optical indices as Olivine_modif.dat, except for an artificial linear interpolation across the 10 and 20 micron features to suppress them (no obvious reason why that would be useful…).

  • ac_opct.dat (amorphous) carbonaceous dust, Rouleau & Martin 1991, ApJ, 377, 526

  • crstsi_opct.dat crystalline silicate dust (olivine), optical constants derived by Li, A., & Draine, B. T. 2001, ApJ, 550, L213, no corresponding optical constants figure in the literature

  • dlsi_opct.dat amorphous silicate dust (“astronomical silicates”) from Draine, B. T., & Lee, H. M. 1984, ApJ, 285, 89

  • ice_opct.dat H2O-dominated “dirty” ice (mostly crystalline) compiled from several sources described in Li, A., & Greenberg, J. M. 1998, A&A, 331, 291. no corresponding optical constants figure in the literature

  • indices_acar.dat “amorphous carbon” optical indices file used by Sebastian Wolf with MC3D (origin?). Judging from the shape of the plots, this material also contain some silicates, though.

  • indices_acar2.dat “amorphous carbon” with high porosity (~85%) optical indices file used by Sebastian Wolf with MC3D (origin?). Judging from the shape of the plots, this material also contain some silicates, though.

  • indices_mc3d.dat “silicates” optical indices file used by Sebastian Wolf with MC3D; identical to the indices in file dlsi_opct.dat, except that this file has no coverage for lambda < 0.2 micron. File indices_mc3d_sil.dat is identical.

  • lgsi_opct.dat amorphous olivine (MgFeSiO_4), based on lab data and synthesized by Li, A., & Greenberg, J. M. 1997, A&A, 323, 566, optical constants displayed as solid line in Figure 1 of Li, A., & Greenberg, J. M. 1997, A&A, 323, 566

  • porousice_james.dat Water ice with optical indices only provided at two wavelengths (very limited usefulness)

  • waterice210K.dat Water ice (at 210K?), as compiled in Pollack et al. 1994, ApJ, 421, 615

  • PAHion.dat ionized PAHs computed by B. T. Draine (compiled from Laor, A., & Draine, B.T. 1993, ApJ 402:441, Draine, B.T., & Lee, H.M. 1984, ApJ 285:89, and Li, A., & Draine, B.T. 2001, ApJ 554:778)

  • PAHneu.dat neutral PAHs computed by B. T. Draine (compiled from Laor, A., & Draine, B.T. 1993, ApJ 402:441, Draine, B.T., & Lee, H.M. 1984, ApJ 285:89, and Li, A., & Draine, B.T. 2001, ApJ 554:778)

Stellar Models

mcfost includes a database of stellar spectra, computed by the Lyon group (F. Allard, I. Baraffe), as well as as the models from R. Kurucz. Models are stored as fits files, each of them with 3 columns : wavelength in micron, flux F_lambda in W/m-2 / micron, and black-body flux at the same Teff.