FLUKA: Re: NEW-DEFA settings

[Alfredo Ferrari <alfredo.ferrari@cern.ch>]

Dear Fan

now I understand better the different timings. Solved this problem, let me
explain the other issue, the protons you see "below threshold".

For all charged hadronic particles and for muons the code transports
accurately (-> with precise dE/dx, multiple scattering etc) down to the
threshold set by the user (10 MeV). Then it ranges them out to 0 energy
JUST IN ONE STEP. If a boundary is met during this step, you can get
particles below the nominal threshold. This approximate range out is
designed to minimize the effect of the threshold, however of course if one
is interested in a precise treatment he should take care to lower the
threshold to a sensible value.

This is NOT done for e- and e+ since a straight-ahead range approximations
would make no sense.

                          Ciao
                         Alfredo

On Mon, 9 Apr 2001, Fan Lei wrote:

> Hi Alfredo,
>
> >
> > why do you use ICARUS at all?? These are very special cuts!!!! They take a
>
> I used ICARUS simply to take the advantage of its default settings for whole
> analogue MC and the low energy thresholds.
>
> > HUGE amount of CPU. To my benchmarks Fluka is usually using the same CPU
> > as GCALOR for the same cuts and geometry (but be sure you have really the
> > same cuts!) within a factor of 2.
>
> The reason for the huge difference in performance between GCALOR and FLUKA
> I mentioned in my previous email is due to delta ray production which was
> not
> switched on in my GCALOR run. After I switched off delta-ray production in
> FLUKA,
> the performance of of these two have become much closer.
>
> I have now used the NEW-DEFA for defaults, see the attached inp file. The
> manual
> says the default cut-off for proton transport is 10 MeV. However as show in
> the attached
> result file, there are many protons below 10 MeV are detected crossing the
> the banduary
> surface, which implies the actual cut-off is lower than 10 MeV!? Is there a
> way to find out
> the exact cut-off values during the run?
>
> Cheers.
>
> Fan
>
>
>
>
>
> The information contained in this e-mail and any subsequent correspondence 
>is private and is intended solely for the intended recipient(s). For those 
>other than the intended recipient any disclosure, copying, distribution, or 
>any action taken or omitted to be taken in reliance on such information is 
>prohibited and may be unlawful.
>

-- 

+----------------------------------------------------------------------------+
|  Alfredo Ferrari                ||  Tel.: +41.22.767.6119                  |
|  CERN-SL                        ||  Fax.: +41.22.767.7555                  |
|  1211 Geneva 23                 ||  e-mail: Alfredo.Ferrari@cern.ch        |
|  Switzerland                    ||          Alfredo.Ferrari@mi.infn.it     |
+----------------------------------------------------------------------------+