Re: FLUKA: ntuple output from FLUKA?

[Alberto Fasso' <fasso@slac.stanford.edu>]

Hi,

On Wed, 31 Jan 2001, Bob Zwaska wrote:

> I'm working on creating particle distributions from proton collisions
> with various targets in FLUKA.  So far I have been using the USRBDX
> option and generating a histogram.  But now we would like more
> particular information on the particles and would like to create an
> ntuple (suitable for use with PAW) carrying a limited, individual record
> for each particle.  Does anyone know if there have been any routines
> created for ntuple output from FLUKA?  And if not, what is the best way
> to access information on individual events?  Would the collision tape be
> the best way going about getting the data?


You don't need to write a collision type: it is easier to
modify the user routine GEODEN, under ENTRY GEOBDX.

I copy here part of a new chapter I am writing for the manual
about the preparation of user routines, which could be useful
for your case.
Note that HBOOK takes only single precision data. Don't forget to
convert to single [ SNGL(RULL) ] all FLUKA floating point data, which are
in double precision

    Alberto

************************************************************************
 --------
 geoden.f FLUKA general scoring routine
 --------
          Subroutine GEODEN is the highest level scoring routine in FLUKA,
          which is called at all events where something happens which
          could contribute to an estimator response (energy deposition,
          end of a step, crossing of a region boundary, elastic or
          inelastic interaction).
          It is not really a user routine, but it has been included in the
          list of user routines because it can be modified to replace
          standard FLUKA scoring with alternative histogramming packages).
          Each type of scorable event corresponds to a different ENTRY
          with its own argument list, which acts as a "switch" to call one
          or more corresponding specific lower-level subroutines. These
          calls can be replaced by calls to other packages desired by the
          user. Please remember that the scored amount (variable RULL), as
          all other FLUKA variables, is in double precision and may need
          to be converted to SNGL(RULL) if transmitted to single precision
          histogramming packages.

          Entries:

          GEODEN  (energy deposition events).
                  Estimators: SCORE, USRBIN, EVENTBIN, DETECT
          Argument list (all variables are input only):
            IJ :    particle or generalized particle type
            XA,YA,ZA: particle position
            MREG:   current region
            RULL:   amount of energy to be deposited (multiplied by particle's
                    weight)
            ICALL:  internal code calling flag (not for general use)
            LLO:    particle generation
            ECONTR: kinetic energy of contributing particle
            ICNTR:  flag = 1 for particle escaping from system, discarded, or
                    in general depositing energy in the blackhole;
                    otherwise = 0
    ....... skip ...............


          GEOSTR  (spallations and fission events).
    ....... skip ...............


          GEOTRK (particle step event)
    ....... skip ...............


          GEOBDX (boundary crossing event)  <===== THIS IS WHAT YOU NEED
                  Estimator: USRBDX
          Argument list (all variables are input only):
            IJ, XA, YA, ZA: see GEODEN above
            TXX, TYY, TZZ: direction cosines of the particle
            MREG:  region before boundary crossing
            NWREG: region after boundary crossing
            RULL:  amount to be scored (weight of the particle if current
                   is being scored; weight of the particle divided by the
                   cosine between its trajectory and the normal to the
                   surface if fluence is being scored)
            ICALL, LLO, ECONTR: see GEODEN above

            GEOBDX handles indirectly boundary crossing fluence (requested
                   by the USRBDX commands) via a call to USRSCX.
                   Note that fluence weighting via user routine FLUSCW is
                   done only inside USRSCX: if the latter are bypassed by
                   the user, no weighting can be applied, even if
                   EXTRAWEIgh has been requested.


          GEOCLL (collision events)
    ....... skip ...............


          GEORSN (production of residual nuclei)
    ....... skip ...............

************************************************************************


-- 
Alberto Fasso'
Stanford Linear Accelerator Center
Radiation Physics Dept. ms 48, 2575 Sand Hill Road, Menlo Park, CA 94025
Tel. +1 650 926 4062        Fax: +1 650 926 3569
fasso@slac.stanford.edu

>From March 1st, 2001:
CERN-EP
CH-1211 Geneve 23 (Switzerland)
Alberto.Fasso@cern.ch