Generating density effect correction files with ESTAR - nrc-cnrc/EGSnrc GitHub Wiki

Custom materials can be added by creating your own density correction files. This is done using the ESTAR program provided by NIST, though currently some manual steps are required to adjust the format to be compatible with EGSnrc.

Go to the ESTAR web application.
Click on unique material to specify a compound or mixture.
Enter a Material Name, density and the formulae and relative weights. Click Submit.
In order to use the same energy grid for the data as in EGSnrc, create a new text file. Copy the data below into a text file. On the ESTAR page, click on the Choose File button under Additional Energies and select the file.

1.00E-03
1.25E-03
1.50E-03
1.75E-03
2.00E-03
2.50E-03
3.00E-03
3.50E-03
4.00E-03
4.50E-03
5.00E-03
5.50E-03
6.00E-03
7.00E-03
8.00E-03
9.00E-03
1.00E-02
1.25E-02
1.50E-02
1.75E-02
2.00E-02
2.50E-02
3.00E-02
3.50E-02
4.00E-02
4.50E-02
5.00E-02
5.50E-02
6.00E-02
7.00E-02
8.00E-02
9.00E-02
1.00E-01
1.25E-01
1.50E-01
1.75E-01
2.00E-01
2.50E-01
3.00E-01
3.50E-01
4.00E-01
4.50E-01
5.00E-01
5.50E-01
6.00E-01
7.00E-01
8.00E-01
9.00E-01
1.00E+00
1.25E+00
1.50E+00
1.75E+00
2.00E+00
2.50E+00
3.00E+00
3.50E+00
4.00E+00
4.50E+00
5.00E+00
5.50E+00
6.00E+00
7.00E+00
8.00E+00
9.00E+00
1.00E+01
1.25E+01
1.50E+01
1.75E+01
2.00E+01
2.50E+01
3.00E+01
3.50E+01
4.00E+01
4.50E+01
5.00E+01
5.50E+01
6.00E+01
7.00E+01
8.00E+01
9.00E+01
1.00E+02
1.25E+02
1.50E+02
1.75E+02
2.00E+02
2.50E+02
3.00E+02
3.50E+02
4.00E+02
4.50E+02
5.00E+02
5.50E+02
6.00E+02
7.00E+02
8.00E+02
9.00E+02
1.00E+03
1.25E+03
1.50E+03
1.75E+03
2.00E+03
2.50E+03
3.00E+03
3.50E+03
4.00E+03
4.50E+03
5.00E+03
5.50E+03
6.00E+03
7.00E+03
8.00E+03
9.00E+03
1.00E+04

Uncheck the Include default energies checkbox. Now, click Submit.
Copy the table data in a spreadsheet and export the two columns Kinetic Energy and Density Effect Parameter to a text file. (You can also use the Download data button; however if you entered a custom mean ionization energy, the downloaded data might be wrong!)
This data is the foundation of your new density correction file for EGSnrc. However, it is necessary to insert the 3-line file header expected by EGSnrc:

line 1: description
line 2: numberOfEnergies meanIonizationEnergy density numberOfElements
line 3: for each element: atomicNumber massFraction
remaining lines: data from ESTAR

The description on line 1 is a comment. On the second line the numberOfEnergies is the number of energies that you saved into the file in step 4 (which should be 113). The meanIonizationEnergy and density are the values in the ESTAR output. The numberOfElements is the number of atomic elements in the material. Finally, line 3 is a list of atomicNumber and massFraction pairs for each atomic element. For example, below is a sample density correction file for water. Save this file with a .density extension, in your $EGS_HOME/pegs4/density/ directory.

water_icru90 calculated with ESTAR, I = 78 eV, rho = 0.998 g/cm3 (20 degree C)
         113   78.00000       0.998000               2
  1 0.111894  8 0.888106
1.000E-03  0.000E+00
1.250E-03  0.000E+00
1.500E-03  0.000E+00
1.750E-03  0.000E+00
2.000E-03  0.000E+00
2.500E-03  0.000E+00
3.000E-03  0.000E+00
3.500E-03  0.000E+00
4.000E-03  0.000E+00
4.500E-03  0.000E+00
5.000E-03  0.000E+00
5.500E-03  0.000E+00
6.000E-03  0.000E+00
7.000E-03  0.000E+00
8.000E-03  0.000E+00
9.000E-03  0.000E+00
1.000E-02  0.000E+00
1.250E-02  0.000E+00
1.500E-02  0.000E+00
1.750E-02  0.000E+00
2.000E-02  0.000E+00
2.500E-02  0.000E+00
3.000E-02  0.000E+00
3.500E-02  0.000E+00
4.000E-02  0.000E+00
4.500E-02  0.000E+00
5.000E-02  0.000E+00
5.500E-02  0.000E+00
6.000E-02  0.000E+00
7.000E-02  0.000E+00
8.000E-02  0.000E+00
9.000E-02  0.000E+00
1.000E-01  0.000E+00
1.250E-01  0.000E+00
1.500E-01  0.000E+00
1.750E-01  0.000E+00
2.000E-01  0.000E+00
2.500E-01  0.000E+00
3.000E-01  0.000E+00
3.500E-01  0.000E+00
4.000E-01  0.000E+00
4.500E-01  0.000E+00
5.000E-01  0.000E+00
5.500E-01  6.126E-04
6.000E-01  1.501E-02
7.000E-01  5.338E-02
8.000E-01  1.005E-01
9.000E-01  1.529E-01
1.000E+00  2.086E-01
1.250E+00  3.535E-01
1.500E+00  4.982E-01
1.750E+00  6.377E-01
2.000E+00  7.704E-01
2.500E+00  1.014E+00
3.000E+00  1.231E+00
3.500E+00  1.426E+00
4.000E+00  1.601E+00
4.500E+00  1.760E+00
5.000E+00  1.906E+00
5.500E+00  2.041E+00
6.000E+00  2.165E+00
7.000E+00  2.390E+00
8.000E+00  2.589E+00
9.000E+00  2.767E+00
1.000E+01  2.928E+00
1.250E+01  3.276E+00
1.500E+01  3.567E+00
1.750E+01  3.817E+00
2.000E+01  4.039E+00
2.500E+01  4.417E+00
3.000E+01  4.734E+00
3.500E+01  5.009E+00
4.000E+01  5.252E+00
4.500E+01  5.469E+00
5.000E+01  5.665E+00
5.500E+01  5.845E+00
6.000E+01  6.010E+00
7.000E+01  6.305E+00
8.000E+01  6.563E+00
9.000E+01  6.792E+00
1.000E+02  6.998E+00
1.250E+02  7.436E+00
1.500E+02  7.796E+00
1.750E+02  8.102E+00
2.000E+02  8.367E+00
2.500E+02  8.810E+00
3.000E+02  9.173E+00
3.500E+02  9.481E+00
4.000E+02  9.747E+00
4.500E+02  9.982E+00
5.000E+02  1.019E+01
5.500E+02  1.038E+01
6.000E+02  1.056E+01
7.000E+02  1.086E+01
8.000E+02  1.113E+01
9.000E+02  1.137E+01
1.000E+03  1.158E+01
1.250E+03  1.202E+01
1.500E+03  1.239E+01
1.750E+03  1.270E+01
2.000E+03  1.296E+01
2.500E+03  1.341E+01
3.000E+03  1.377E+01
3.500E+03  1.408E+01
4.000E+03  1.435E+01
4.500E+03  1.458E+01
5.000E+03  1.480E+01
5.500E+03  1.499E+01
6.000E+03  1.516E+01
7.000E+03  1.547E+01
8.000E+03  1.574E+01
9.000E+03  1.597E+01
1.000E+04  1.618E+01