Simulating bremsstrahlung incident on Ra226 target

Hello everyone,

I have simulated an electron beam incident on a tungsten target to produce bremsstrahlung.
I am attempting now to place a Ra226 target directly behind the tungsten.
I have tried several ways to assign Ra226 as the target material in my .tg file, but noting has worked.
Is it possible to assign an isotope to the material using text based geometry files?
If so can someone explain the proper syntax to use please?


You can put something like:
:ISOT Ra220_I 88 220 216.003
:ELEM_FROM_ISOT Ra220_E Ra220_E 1 Ra220_I 1.
:MIXT Ra220 5 1 Ra220_E 1.

Hi arce,

That worked thanks!
could you point me towards the relevant documentation for this please?

The Geant4 Bool for Application Developers, section
4.1.14 Importing ASCII Text Models
points you the text geometry manual