From: adwasil@poczta.onet.pl
Date: Fri Apr 29 2005 - 08:49:55 CEST
I've defined AIR material myself. But something is still not correct. I've obtained a massage **** Low energy neutron xsec not found for some media 4 5 ****. I think all used materials such as NITROGEN, OXYGEN, ARGON and CARBON are defined in FLUKA neutron library. Should I switch some option/command on to use cross section of these elements for compound (AIR)?
What am I still doing wrong?
Best regards
Adam
file.inp:
TITLE
Electron to photon to neutron on tungsten
DEFAULTS PRECISIO
*23456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789
BEAM -0.007 ELECTRON
BEAMPOS 0. 0. -30. 0. 0.
EVENTYPE 2. DPMJET
GEOBEGIN COMBINAT
geometry definition
SPH 1 0. 0. 0. +9000000.
RPP 2-1000000. +1000000. -1000000. +1000000. -1000000. +1000000.
SPH 3 0. 0. 0. +100.
RCC 4 0. 0. -3.5 0. 0. 7.
10.
RPP 5 -20. +20. -20. +20. +100.1 +100.2
END
* black hole region
1 5 +1 -2
* vacuum around (outer)
2 5 +2 -3 -5
* air around (inner)
3 5 +3 -4
* tungsten target region (7cm thick, 10cm radius)
4 5 +4
* forward detector region
5 5 +5
END
GEOEND
*---o---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7----
* Z Mass Dens[g/cm3] Index Not.used Name
*MATERIAL 74. 184. 19.3 23. TUNGSTEN
*MATERIAL 4. 9.0122 1.848 5. BERYLLIU
MATERIAL 18. 39.948 1.662E-3 26. ARGON
MATERIAL 0. 0. 0.0012048 24. AIR
COMPOUND -9.1E-4 7. 2.79E-4 8. 1.55E-5 26. AIR
COMPOUND 1.49E-7 6. AIR
*
*---o---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7----
*
*ASSIGNMAT (material==>region)
* tungsten target
ASSIGNMAT 23. 4.
* forward detector region
ASSIGNMAT 24. 5.
* Outer vacuum
ASSIGNMAT 2. 2.
* Inner air
ASSIGNMAT 24. 3.
* External Black Hole
ASSIGNMAT 1. 1.
PHOTONUC 1. 0. 0. 4. 24. 1.
LAM-BIAS 0. 0.00005 0. 7.
*23456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789
*---o---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7----
*EMF EMF-OFF
* **** Scoring ****
USRBDX +1. 7. -31. 3. 2. PHOTON
USRBDX +0.02 300. 1. &
USRBDX +1. 3. -32. 3. 2. ELECTRON
USRBDX +0.02 300. 1. &
USRBDX +1. 8. -33. 3. 2. NEUTRON
USRBDX +0.02 +1.E-5 300. 1. &
*---o---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7----
USRBDX +1. 7. -41. 5. 2. PHOTON
USRBDX +0.02 300. 1. &
USRBDX +1. 3. -42. 5. 2. ELECTRON
USRBDX +0.02 300. 1. &
USRBDX +1. 8. -43. 5. 2. NEUTRON
USRBDX +0.02 +1.E-5 300. 1. &
RANDOMIZE 1.
*---o---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7----
START 50. 1.0
STOP
On Thu, 28 Apr 2005, 20:10 Alberto Fasso wrote
> FLUKA neutron cross sections are for single elements or isotopes, not for
> compounds and mixtures. The error message is due to the fact that no cross
> section with a name AIR* can be found in the neutron library.
> But this just one of many reasons why pre-defined compound materials
> (those with a * in their name) should NEVER be used. They are there for
> historical reasons, but their use can give problems, or at least
> inaccurate results. I hope that they will disappear in the next FLUKA
> release.
>
> Alberto
>
> On Thu, 28 Apr 2005 adwasil@poczta.onet.pl wrote:
> > I try to find a difference in neutron transport in vacuum and air. that
> > While I'm using vacuum instead of air everything is OK, but wile I'm
> > using fluka material 24 I obtain an error massage **** Low energy neutron
> > xsec not found for some media 1 2 ****.
> > What am I doing wrong?
> > Best regards
> > Adam
This archive was generated by hypermail 2.1.6 : Fri Apr 29 2005 - 09:15:33 CEST