allows to alter material density for dE/dx and nuclear processes on a
region-by-region basis
See also ASSIGNMAt, COMPOUND, LOW--MAT, MATERIAL, MAT-PROP
WHAT(1) >= 0.0 : density scaling factor for charged particle ionisation
processes (dE/dx, delta ray production, M\oller and Bhabha
scattering)
= 0.0 : ignored
< 0.0 : reset to default
Default: 1.0
WHAT(2) >= 0.0 : density scaling factor for all other processes
= 0.0 : ignored
< 0.0 : reset to default
Default: 1.0
WHAT(3): not used
WHAT(4): lower index bound of regions where the scaling factors shall apply
"From region WHAT(4)..."
Default: 2.0
WHAT(5): upper index bound of regions where the scaling factors shall apply
"...to region WHAT(5)..."
Default: WHAT(4)WHAT(6): step length in assigning region numbers
"...in steps of WHAT(6)"
Default: 1.0
SDUM : not used
Default (option CORRFACT not requested): no density scaling factors are
applied
Note:
1) Option CORRFACT is mainly used in connection with voxel geometries
derived from a CT scan, where particle transport is done often in an
equivalent material (e.g., water), but accounting for the density
variations provided by scan at the voxel level. While this approach
is reliable for what concerns ionisation, other reactions, which do
not scale with density, must be simulated for the actual material
composition.
Example:
*...+....1....+....2....+....3....+....4....+....5....+....6....+....7...
* Multiply density by a 0.85 factor for what concerns atomic processes
* in regions 7, 8, 9, 10, 11, 12
CORRFACT 0.85 0.0 0.0 7.0 12.
