RE: fluence spectra

 Hello Mario

Thank you very much, this was helpful.
I have divided my water target volume into 6 regions for 6 USRTRACKs each
with one energy bin. However, I could not load them in FLAIR. Instead, I
have uesd the standard output file (events by region scoring) to observe the
results. Unfortunatley I have found firist region result only while the
others were zero. Please refer to the attached input file and tell me where
the error is.
I have also tried to divide the initial proton energy to 1/6 for each
USRTRACK. Please let me know if this was correct. Also would you please tell
me if there is away to see the output result in FLAIR since I have to do it
for so many regions.

Thanks once again and best regards
Leena
________________________________________
From: owner-fluka-discuss_at_mi.infn.it [owner-fluka-discuss_at_mi.infn.it] On Behalf Of Santana, Mario [msantana_at_slac.stanford.edu]
Sent: 23 July 2010 04:07
To: Al-Sulaiti L Ms (PG/R - Physics)
Cc: fluka-discuss_at_fluka.org
Subject: Re: fluence spectra

Laena,

In your input file you are scoring PROTON fluence in a R-PHI mesh centered
at x=0, of radius 4 and depth (z) 3.2 cm. The fluence is the density
of track-lengths for your protons, so the units are
cm/cm^3=cm^2. Now, of course FLUKA expresses the results per primary
particle. So 1/cm^2/starting_proton. You need to multiply the result by the
number of protons per second that you shoot into your target.

If you want to have the spectra of your fluence then use USERTRACK. In that
  case you will obtain the differential spectra dfluence/dE (units are
1/cm^2/GeV/starting_proton) for the energy grid (linear or logarithmic) that you request, but you will not be able to simultaneously sort the results in a
3-D grid (like with USRBIN). Instead, you will have to request your spectra
for the PROTONS that cross a given region of your geometry. I suggest that
you split your volume in several disk regions and that you use several
USERTRACK cards associated with those regions. Then you could load all those
in FLAIR (or gnuplot) to see how your spectrum changes with the depth.

In case of further doubt I suggest you to read this:
http://www.fluka.org/fluka.php?id=n_onl&sub?
http://www.fluka.org/fluka.php?id=n_onl&sub?

Mario