RE: multigroup technique for low neutrons- a deterministic method or Monte Carlo?

Hi Carolin,

The multigroup technique is a method to describe the neutron cross sections and the outcome of the neutron interactions in an implicit way. The other method is to use point-wise cross section and handle explicitly all interactions.

Look the beginners course lecture on low energy neutrons. The Cross section is "weighted" and averaged over each energy group, with a typical neutron spectrum, Maxwell Boltzmann distribution in the thermal region and isolethargic above. Most of the interactions are handled with the down-scattering matrix but some are treated explicitly.

You can use the multigroup method both in deterministic methods as well in Monte Carlo. FLUKA is using it in a MC way. Therefore your simulation with FLUKA is ONLY a Monte Carlo simulation.

Regards
Vasilis

________________________________________
From: owner-fluka-discuss_at_mi.infn.it [owner-fluka-discuss_at_mi.infn.it] on behalf of Carolin Pezenka [carolin.pezenka_at_student.tu-freiberg.de]
Sent: 19 November 2012 21:36
To: fluka-discuss_at_fluka.org
Subject: multigroup technique for low neutrons- a deterministic method or Monte Carlo?

Dear FLUKA-Experts,

while writing the theoretical background of my master thesis about
monte carlo simulations in well logging problems I get confused. In
the simulations I am using neutrons with energies below 20 MeV and so
the multigroup technique is used. Isn't this technique a deterministic
method and not a Monte Carlo Method? Does my simulation consist of
both methods or is the simulation in spite of the multigroup approach
still a Monte Carlo Simulation?

I hope, that somebody can help me with an explanation.
Kind regards
Carolin Pezenka
Received on Fri Nov 23 2012 - 16:41:57 CET