Re: Multiple particle types in beam

Hi Joe

there is no particular subtle issue. The BEAM card is essential in
determining up to which energy xsec and dE/dx tabulations are initialized,
but for this purpose only the beam energy is relevant not the beam id.
In practice a proton or whatever beam of energy larger or equal than the
maximum energy you are using in the source routine will work.

                 Ciao
                Alfredo

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On Wed, 5 Oct 2011, Joseph Comfort wrote:

> I am using a source.f file to read events from a file. The 'beam' file
> has a a mixture of particles, each with its own id, in addition to
> position and momentum components. It comes, for example, from an
> intermediate stage of the full MC calculation.
>
> Because IJBEAM is set by a BEAM card, I set a variable ibbeam to the
> particle id. The section of the code labeled 'Normal hadron' is
> modified so that the variables IONID and ILOFLK(NPFUKA) are set to
> ibbeam. This seems to work.
>
> Two questions: (1) Are there any subtle issues that could cause
> problems? (2) What is the meaning/role of the BEAM card? I have
> included a card for the most abundant particles in the file, to set an
> energy range. But I don't know if this is meaningful. What happens if
> the card is left out?
>
> Thank you,
> Joe Comfort
>
Received on Thu Oct 06 2011 - 09:44:14 CEST