ATLAS9 Model Atmospheres for the APOGEE survey

Current updates are described in the News section.

This website contains ATLAS9 model atmospheres, fluxes, ODFs and Rosseland opacity files calculated for the APOGEE sky survey. The website contains ATLAS9 model atmospheres spanning temperatures from 3500K to 30000K, and log g from 0 to 5 for 2099 individual compositions with varying [C/M] and [A/M] content (see below). The data are available for download from the menus on the left side. Carbon rich models with C/O > 1.7 and Teff < 4000K are not published, because polyatomic carbon molecules not included in the linelists significantly change the atmospheric structures.

Quick download of all models with [C/M]=[A/M]=0 can be found here:

[C/M] = [A/M] = 0
Models ODFs Fluxes Statistics
[M/H] from -5 to +1.5 (22 comp.) Download(28.7MB) Download(557MB) Download(25.7MB) Download

Quick download of all models with [C/M]=0, [A/M]=+0.4 can be found here:

[C/M] = 0, [A/M] = +0.4
Models ODFs Fluxes Statistics
[M/H] from -5 to +1.0 (21 comp.) Download(27.0MB) Download(521MB) Download(24.1MB) Download

All model atmospheres and fluxes can be downloaded from here (the [A/M]=+0.4 models are currently not included in these tar files):

All [C/M] and [A/M] variations Models Fluxes
[M/H] from -5 to +1.5 (2099 comp.) Download(2.5GB) Download(2.2GB)

Individual compositions are available from the left panel.

Model Atmospheres

There are three main differences from previous model grids:

  1. a new H2O linelist provided by Robert Kurucz,
  2. wide range of carbon ([C/M]) and alpha-element [A/M]
  3. abundances from Asplund et al. 2005

 The common physical parameters of all ATLAS9 models:

  1. vmicro = 2 km/s
  2. alpha elements: O, Ne, Mg, Si, S, Ca
  3. mixing length parameter: l/H = 1.25
  4. 72 layers from log tau_Ross = -6.875 to 2, step is 0.125

The effective temperature and log g grid for each metallicity is the following:

 S.T. Teff Min. Teff Max. Teff step log g Min. log g Max. log g step
M, K, G
3500 6000 250 0 5 0.5
F 6250 8000 250 1 5 0.5
A 8250 12000 250 2 5 0.5
B 12500 20000 500 3 5 0.5
B, O 21000 30000 1000 4 5 0.5

 

ODFs and Rosseland Opacity Files

ODFs and Rosseland opacity files are available for 2099 different compositions (for missing compositions please see this page):

  Min. Max. Step
[M/H] +1.0 +1.5 0.5
[C/M] -1.5 +1.0 0.5
[A/M] -1.5 +1.0 0.5
 
[M/H] -3.0
+0.75 0.25
[C/M] -1.5 +1.0 0.25
[A/M] -1.5 +1.0 0.25
 
[M/H] -5.0  -3.5 0.5
[C/M] -1.0 +1.0 0.5
[A/M] -1.0 +1.0
0.5

ODFs with big intervals are available for vmicro = 0, 1, 2, 4 and 8 km/s.