[Brahms-dev-l] geant track corrections

As we have discussed this has made it into a correction object that it should be fairly easy to use in 
the analysis stages.

i)    The correction ascii files are generated thorugh the steps of brag-brat-dst-dstanalysis and results in
data files with names  Eff_<runperiod>_<Particle>_<angle>_<physicsoption>[_<cut<cutfactor>].data
Rather than using runs, it seems these are basically independent of runno, and for run5 there is no difference between
pp and cucu. Run 4 is really only auau, and run3 dau and pp with same physics setup.

ii) A subdirectory geant has been added to banapp/corrections.

iii) The easiest way to see the usage of the class is to look into the example script TestFsCorrections.C that
      plots corrections from a official data in /brahms/data08/corrections/geantSim/ and TestEval.C that illustrates
      how to get a correction from the class.

iv) The correction is estimated from a cubic spline function to the supplied data. Since such description do go through all
     datapoints, it sometimes do show small wiggles at the <=1% level. This is probably ok.
     The Eval method return 1.0/eff i.e. the factor you want to multiply (a number >1) . In addition it return 0. if p< minimum momenta and
     the correction at the highest momenta if p> range. Note that p has to be positive. 

v)  The scripts that generates files in brahms_app/fv_app/Simu/eff has been updated to reflect the chang in naming convention, as well
     as the output to the first couple of lines in the ascii files. Note that the GeantCorrection class can only use files with this specific format.

Flemming



--------------------------------------------
Flemming Videbaek
Physics Department 
Bldg 510-D
Brookhaven National Laboratory
Upton, NY11973

phone: 631-344-4106
fax:        631-344-1334
e-mail: videbaek @ bnl.gov


_______________________________________________
Brahms-dev-l mailing list
Brahms-dev-l@lists.bnl.gov
http://lists.bnl.gov/mailman/listinfo/brahms-dev-l