Atlas9 Materials


This page provides products related to the Atlas9 grids described in the paper "New limb-darkening coefficients and synthetic photometry for model-atmosphere grids at Galactic, LMC, and SMC abundances", MNRAS 413, 1515, 2011 (available as submitted version and MN edit; I prefer my version!).

ODFs

The ODFs directory contains opacity-distribution functions for use with the Trieste port of Atlas9 (by Castelli and others). The standard syntax is used; e.g.,
      P03bigvt04.bdf
is the ODF for [M/H]=+0.3 ('P' for 'plus') with 'big' sampling intervals, and v(turb) = 4 km/s. The matching Rosseland opacity file is kapP03.ros (and the corresponding abundances are listed in the file 00abund.P03).

The ODFs available here are a superset of those used in the paper, including scaled solar-abundance models at steps of [M/H]=0.1 from -1.0 to +1.0; files are gzipped to save space.

Atlas9.C04

The Atlas9.C04 directory contains grids of products (fluxes and limb-darkening coefficients, described below) newly generated from the atmospheric structures published by Castelli & Kurucz (2004). Subdirectories have names of the form, e.g., "m20v02" or "p05av02", where
      m20v02 means [M/H] = -2.0 ('m' for 'minus'), v(turb) = 2 km/s
      p05av02 means [M/H] = +0.5 ('p' for 'plus'), alpha elements enhanced, v(turb) = 2 km/s
The Atlas9.C04 models use Grevesse & Sauval (1998) solar abundances, and mixing-length parameter l/H=1.25

Atlas9.A10

The Atlas9.A10 directory contains grids of products from newly calculated structures. Subdirectory naming follows that in Atlas9.C04, except that M/P are used as abundance ([M/H]) -/+ prefixes.

The models are based on Asplund et al. (2005) solar abundances, and mixing-length parameter l/H=1.25; subdirectories suffixed "r" are for models with l/H=0.5. Model grids at notionally LMC and SMC abundances are included.

Data products

Within each grid subdirectory there are three plain-text files for each model, with names of the form 't12345g67.(ext)', where the base identifies the effective temperature and log(g), and the extension identifies the file content. (The abundance and turbulent velocity are identified by the subdirectory name.)

Files with '.flx' extensions contain listings of physical fluxes at 1221 wavelengths, from 90 angstrom to 160 micron (with 20-angstrom sampling through the optical). Fluxes are tabulated in erg/cm2/s/ang, as a function of wavelength (in angstrom).

Limb-darkening coefficients are provided in files with extensions '.ucP' (for photon-counting detectors) and '.ucE' (for energy-integrating detectors). Broad-band limb-darkening coefficients are in the following format, illustrated by V-band results for the 9.55kK Vega model:

Here the first line lists

  1. the passband,
  2. the effective wavelength (in angstrom),
  3. the broad-band physical flux (in erg/cm2/s/A),
  4. the broad-band surface-normal intensity (in erg/cm2/s/A/sr), and
  5. the bolometric correction (for Johnson passbands only).

Subsequent lines list coefficients for various limb-darkening laws (see paper for details). The final two numbers in each row are the r.m.s. and maximum differences between input and modelled values of I(mu)/I(1).

Single-file downloads

For convenience, all files of a given file type (e.g., "flx" files) for a given subdirectory (i.e., for given abundance and v_turb) are provided as individual gzipped tar files. For example, the file
      ucE_SMCv02.tgz
contains the 'ucE' files for all the models in the SMCv02 directory.

As a further aid to anyone interested only in limb-darkening coefficients, the 'ucP' limb-darkening coefficients for all models in each Atlas9.C04/A10 grid have been reformatted into single ascii files, available in the uCoeffs directory

CDS links

The CDS provides a permanent repository for the most important plain-text data files:

ftp://cdsarc.u-strasbg.fr/pub/cats/J/MNRAS/413/1515

http://cdsarc.u-strasbg.fr/cgi-bin/VizieR?-source=J/MNRAS/413/1515