This site informs about the structure of files of the COMPTRA database. The files contain information on the composition and transport coefficients of plasmas.

Composition files *_comp

Composition files contain lists of fractions of atoms (alpha_0) and the different ions (alpha_x...alpha_y) on the amount of heavy particles at given temperatures and densities, as well as an average ionisation degree alpha_e = n_e / n_heavy. The information in the first lines mean:

• output as compositions of constant temperature
• element, defined by ordering number
• no molecules are considered
• number of temperatures
• number of densities that also occure in SESAME file

After that, the instability region known in PIP is defined for each given temperature by the number of the last value that doesn't belong to the temperature, and the number of points that belong to said instability region. The next line specifies the fractions of ions with a charge x...y that will be shown afterwards.

Example: If you have a look at file al10-30K_comp, you will find 3 lists of compositions - one for each temperature. Usually, these lists contain 50 densities. An exception is T=10000 K: Here, an instability region was found with PIP. Therefore, you have 6 additional density values that start at the 40^th value (ρ=0.566 g/cm³), and belong to said instability. Shown are mass density, number density of heavy particles, average ionization degree, and fractions of particles Al^Z+ with charges Z=0..2 in case of 10000 K, Z=0...3 else.

Transport Coefficient files *_trans

These files contain lists of electrical conductivities σ, thermal conductivities λ, thermopower κ, and Lorentz number L for the set of densities and temperatures given in the respective composition file *_comp. The structure is similar to *_comp files: The first lines define the output format (lists for constant temperature), the material, number of temperatures and densities that occur in the SESAME file. The instability region is handled similarly to the composition: If you look at al10-30K_trans, only for 10000 K an instability occurs. The densities belonging to that region start at the 40^th value and end at the 46^th.

SESAME files *_sesa

SESAME files are originally created to store state variables z(x,y). Since the SESAME equation of state database is widely used, so is the file structure of SESAME files. Here, we provide data from the transport coefficient files *_trans in the SESAME format: We give data for σ, λ, and κ as functions of mass density ρ and temperature T.
SESAME files start with a number that defines the material. Originally, a special number from a list is used, but here you will find the ordering number. Also in this line you will find the atom mass and the number of values ρ₁...ρ_m... and T₁...T_n. That is the first line. The next lines are given in columns of four values. They contain ρ₁...ρ_m, followed by T₁...T_n. Then, the values σ_1,1... σ, _m,1,σ_1,2... σ_m,n are given, followed by λ_1,1... λ_m,n and κ_1,1... κ_m,n

Example: If you have a look at al10-30K_sesa, you find 13 as ordering number, 0.26982E+02 as atom mass, 50 density points, and 3 temperature points in the first line. Then you find the density and temperature values from al10-30K_trans that do not belong to the instability. After those 50+3=53 values, the output for the electrical conductivity starts with σ(0.001 g/cm³,T=10000 K).