Energy Deposition

Hi;
 
 I am a new user for FLUKA and i have a question.
 
 /I want to have energy deposition in each meshed volume (dx=0.5mm, dy=0.5mm,
 dz=1.7mm) in W75Re25 amorphous target from electron beam and i used USRBIN
 card for that.
 
 My parameters;
 
 for Beam;
 Beam energy=2GeV
 Beam Size=1.6(r) mm
 N e- per pulse=208*1010 e-
 
 for Target;
 Target Material=W75Re25
 //Target Thickness=4.5X0 (X0=0.3439cm)
 
 The simulation were performed to the depth of 10 X0 to see the whole
shape of the shower distribution around the peak energy-deposition density.
 The peak density resides around the depth of 4.0 X0. Everything is right
 except max energy deposited value. It has to be 0.64*1010 but my result is
 0.28*1010. There is a difference about factor 2.
 
 And also, which value should i select for beam radius? for gauss,
 fwhm=sigma*2.355. and my value is 0.16cm. x(fwhm)=y(fwhm)= 0.16 or 0.16*2.355
 and so i selected both of them but there is not a big difference.
 
 I am sending you my input file. Can you help me?
 
 Thanks in advance
 Emre

 
 TITLE
 Positron production at Linear Collider
 BEAM -2.0 0.0 0.0 -0.16 -0.16 0.0ELECTRON
 BEAMPOS 0.0 0.0 0.0
 GEOBEGIN COMBNAME
    0 0 Thick slab geometry
 RPP exVoid -10000.0 10000.0 -10000.0 10000.0 -10000.0 10000.0
 RPP inVoid -100.0 100.0 -100.0 100.0 -5.0 30.0
 RPP box -0.8 0.8 -0.8 0.8 0.0 20.0
 XYP cutZ 3.439
 END
 * Black hole around the geometry
 blkHole 5 +exVoid -inVoid
 expHole 5 +inVoid -box
 * Target
 target 5 +box +cutZ
 * vacuum after Target
 magnet 5 +box -cutZ
 END
 GEOEND
 MATERIAL 75.0 186.207 21.02 26. RHENIUM
 MATERIAL 0.0 0.0 19.613 27. W75RE25
 MATERIAL 0.0 0.0 0.0012048 28. AIR
 COMPOUND 1.24D-4 CARBON 0.755267 NITROGEN 0.231781 OXYGENAIR
 COMPOUND 0.012827 ARGON 0.0 0.0 AIR
 COMPOUND 75.0 TUNGSTEN 25.0 RHENIUM W75RE25
 ASSIGNMA BLCKHOLE blkHole
 ASSIGNMA VACUUM expHole
 ASSIGNMA W75RE25 target
 ASSIGNMA VACUUM magnet 1.
 MGNFIELD 0.0125
 DEFAULTS PRECISIO
 SCORE ENERGY EM-ENRGY ALL-PART
 * deposited energy in Target
 USRBIN 10. ENERGY -21. 0.8 0.8 3.439edep
 USRBIN -0.8 -0.8 0.0 32. 32. 20.&
 
 RANDOMIZ 1.
 START 10000. 0.0
 STOP
 
Received on Mon Jun 08 2009 - 17:56:37 CEST