Re: Particle LET, Part II

From: Joel DeWitt (joel.m.dewitt@gmail.com)
Date: Wed Oct 31 2007 - 20:38:40 CET

  • Next message: Vitaly Pronskikh: "Re: low energy neutrons, binning and complementary software"

    Since LET is proportional to the square of the particle charge, I would like
    to score pretty much everything with some measure of charge
    (fragments+primaries). Attached is an experimental sample to illustrate
    what I mean. Input contents:

    TITLE
    Arthur
    #if 0
    * Example from page 90
    DELTARAY 0.01 30.0 0.0 ALUMINUM PE NOPRINT
    #endif
    #if 0
    DELTARAY 0.02 0.0 1.05 AIR WATER 8.0NOPRINT
    #endif
    * blackhole
    ASSIGNMA BLCKHOLE BLKHOLE
    * air
    MATERIAL 0.001225 AIR
    * air
    COMPOUND -9.256D-4 NITROGEN -2.837D-4 OXYGEN -1.572D-5 ARGONAIR
    * air
    ASSIGNMA AIR VAC
    * air
    STERNHEI 10.5961 1.7418 4.2759 0.10914 3.3994 AIR
    DEFAULTS NEW-DEFA
    * 1 GeV/n 56Fe
    BEAM -56.0 -0.082425 -1.7 1.0 1.0 1.0HEAVYION
    HI-PROPE 26.0 56.0
    #if 0
    * Example 1 from page 157
    * MULSOPT is very CPU-time consuming; however, it gives the highest accuracy compatible with the Moli`ere theory.
    * In order to get the most accurate treatment of Multiple Coulomb Scattering, a step optimisation and higher
    * order corrections can be requested by option MULSOPT (but with an important increase in CPU time).
    MULSOPT 1.0 1.0 2.0 ALUMINUM PE 5.0
    #endif
    #if 0
    * Example from page 158
    MUPHOTON 1.0 0.0 0.0 ALUMINUM PE
    #endif
    #if 0
    PAIRBREM 3.0 0.0 0.0005 ALUMINUM PE
    #endif
    #if 0
    * Example 1 from page 173
    PAIRBREM 3.0 0.0 0.0012 ALUMINUM PE 3.0
    #endif
    #if 0
    MUPHOTON 1.0 0.0 0.0 ALUMINUM PE 3.0
    #endif
    BEAMPOS 0.0 0.0 -100.0 0.0 0.0
    GEOBEGIN COMBNAME
    0 0 Arthur
    SPH BLK 0.0 0.0 0.0 10000.0
    RPP VOI -1000.0 1000.0 -1000.0 1000.0 -1000.0 1000.0
    YZP x2down -2.0
    YZP x2up 2.0
    XZP y2down -2.0
    XZP y2up 2.0
    YZP x5down -5.0
    YZP x5up 5.0
    XZP y5down -5.0
    XZP y5up 5.0
    * aluminum START
    XYP z1AL 0.0
    * aluminum END (5 g/cm^2, 2.70 g/cm^3, 1.85 cm)
    XYP z2AL 1.85
    * polyethylene START
    XYP z1PE 1.85
    * polyethylene END (5 g/cm^2, 0.92 g/cm^3, 5.43 cm)
    XYP z2PE 7.28
    * CR-39 START (water)
    XYP z1CR39 7.28
    * CR-39 END (water; detector thickness: 0.05 cm)
    XYP z2CR39 7.33
    END
    BLKHOLE 5 +BLK -VOI
    * aluminum
    AL 5 -x5down +x5up -y5down +y5up -z1AL +z2AL
    * polyethylene
    PE 5 -x5down +x5up -y5down +y5up -z1PE +z2PE
    * CR-39 (water)
    CR39 5 -x2down +x2up -y2down +y2up -z1CR39 +z2CR39
    VAC 5 +VOI -( -x5down +x5up -y5down +y5up -z1AL +z2AL ) -( -x5down +x5up
    -y5down +y5up -z1PE +z2PE ) -( -x2down +x2up -y2down +y2up -z1CR39 +z2CR39 )
    END
    GEOEND
    * aluminum
    ASSIGNMA ALUMINUM AL
    * aluminum
    STERNHEI 4.2395 0.1708 3.0127 0.08024 3.6345 0.12ALUMINUM
    * polyethylene
    MATERIAL 0.92 PE
    * polyethylene
    COMPOUND 1.0 CARBON 2.0 HYDROGEN PE
    * polyethylene
    ASSIGNMA PE PE
    * polyethylene
    STERNHEI 3.0016 0.137 2.5177 0.12108 3.4292 PE
    * CR-39 (water)
    MATERIAL 1.0 WATER
    * CR-39 (water)
    COMPOUND 2.0 HYDROGEN 1.0 OXYGEN WATER
    * CR-39 (water)
    ASSIGNMA WATER CR39
    * CR-39 (water)
    STERNHEI 3.5017 0.24 2.8004 0.09116 3.4773 WATER
    #if 0
    * Example from page 143
    LOW-NEUT 72.0 22.0 0.0196 0.0 -11.0
    #endif
    #if 0
    * Example from page 152
    MCSTHRES 1.0 -0.01
    #endif
    #if 0
    STEPSIZE 0.3 AL PE
    #endif
    * energy deposition
    USRBIN 10.0 -40.0 6.0 6.0 8.0Energy
    USRBIN -6.0 -6.0 -1.0 100.0 100.0 100.0&
    * score the LET spectrum (in water) of charged particles
    USRYIELD 2323.0 ALL-CHAR -41.0 PE CR39 1.0Yield
    USRYIELD 200.0 0.0 200.0 200.0 0.0 2803.0&
    RANDOMIZ 1.0
    * From Dreamweaver (BF1112_0.ASF): 3,267 cm^-2*16 cm^2 = 52,272 ions
    START 52272.0 0.0
    STOP

    At the time being I'm only seeing the primary peak for 1 GeV/n 56Fe (behind some shielding), but no
    low- or high-charge fragments. The sample does not represent my FLUKA
    system; it's just an example.

    I have been through the manual and played with some of the physics and
    transport cards to see if something wasn't "on". But I think the simplest
    solution (i.e. how I'm scoring) is probably at fault.

    Any input you can provide will be vastly appreciated.

    Many thanks,
    Joel DeWitt
    Eril Research, Inc.




    Blank_Bkgrd.gif
    sample.gif
  • Next message: Vitaly Pronskikh: "Re: low energy neutrons, binning and complementary software"

    This archive was generated by hypermail 2.1.6 : Thu Nov 01 2007 - 11:17:15 CET