[fluka-discuss]: RE: Carbon cross section

From: Vasilis Vlachoudis <Vasilis.Vlachoudis_at_cern.ch>
Date: Tue, 10 Jun 2014 08:15:42 +0000

Hi Eleni,

the LOW-MAT library do not set the density, it only affects the low energy neutron cross sections.
"Free gas natural Carbon" refers to the cross section of carbon assuming it behaves like a free gas.
Each atom is in depended of the others, there is no bond between them.

The density you have to set it with the appropriate MATERIAL card.

The "bound nat." affects mostly the thermal treatment of the cross sections of materials assuming that are bounded inside
some lattice/molecule, known as S(a,b) treatment.

Vasilis

________________________________
From: owner-fluka-discuss_at_mi.infn.it [owner-fluka-discuss_at_mi.infn.it] on behalf of Eleni Aza [eleni.aza_at_cern.ch]
Sent: 10 June 2014 09:40
To: fluka-discuss_at_fluka.org
Subject: [fluka-discuss]: Carbon cross section


Dear all,



I am trying to simulate the response function of a neutron moderating sphere, made of what I think is graphite.



Apparenlty when I use "Carbon gas" for the LOW-MAT card I get more interactions than when I use "Carbon graphite", which doesn't sound right to me.



It seems that there are 3 options for carbon in the fluka library:



1. Carbon gas (density ?)

2. Carbon graphite (density 2.26)

3. Carbon amorphous (density 2)



I would like your help with the Carbon gas density and also information about which material is more appropriate for my application.



Thank you!



Regards,
Aza Eleni
+41 (0)22/76 77326
Received on Tue Jun 10 2014 - 11:27:58 CEST