Dear Vittorio,
Thank you for the answer. I repeated my simple simulation and these are the complete results for some scored quantities:
10000 primaries, 4 cycles. USRBIN X-Y-Z, 1bin along each volume dimension
-- MULSOPT disabled (total multiple scatt. = 6.265E+4, single scat. = 0) 0.05 ms/ primary
DPA-SCO 2.7064E-013 (err. 1.6351E-003%)
DOSE 1.8507E+006 (err. 1.3555E-002%)
NIEL-DEP 4.4372E+003 (err. 1.5940E-003%)
-- MULSOPT enabled (total multiple scatt. = 0, single scatt. = 1.8E+6) 30 ms/ primary
DPA-SCO 2.7044E-013 (err. 1.9703E-003%)
DOSE 1.8502E+006 (err. 1.0102E-002%)
NIEL-DEP 4.4338E+003 (err. 1.9007E-003%)
Since the results show negligible differences, despite a longer simulation time, has single scattering no influence in the scored quantities that I have considered? Moreover, I am a beginner user of FLUKA, so, please, can you suggest me how to set LAM-BIAS for my specific geometry/ problem, or indicate me some example about this bias?
Best regards,
Giuseppe
__________________________________________________________
Giuseppe Prestopino
Università di Roma "Tor Vergata"
Dipartimento di Ingegneria Industriale
Via del Politecnico 1
I-00133 Roma, Italy
Tel. +390672597238
<mailto:giuseppe.prestopino_at_uniroma2.it> giuseppe.prestopino_at_uniroma2.it
Da: Vittorio Boccone [mailto:dr.vittorio.boccone_at_ieee.org]
Inviato: lunedì 24 novembre 2014 22.58
A: Giuseppe Prestopino
Cc: fluka-discuss_at_fluka.org
Oggetto: Re: [fluka-discuss]: radiation damage in thin target
Dear Giuseppe,
I don't understand what would you expect? Which is the statistical uncertainty of the scoring for both simulations?
All the score dose, DPA, non ionizing energy losses etc are cause by the prompt radiation and fragments.
You already implemented most of the suggestion coming from the threads in within this reply (one of which is actually your thread):
http://www.fluka.org/web_archive/earchive/new-fluka-discuss/7375.html
1) Summarizing: Use LAMBIAS
2) Coalescent On (you already have it)
Best,
Vittorio
On Fri, Nov 21, 2014 at 6:26 PM, Giuseppe Prestopino <giuseppe.prestopino_at_uniroma2.it> wrote:
Dear FLUKA experts,
I am trying to evaluate radiation damage by low energy heavy ions in a carbon thin target. I am using 4 MeV (total energy) Carbon primaries that hit a small volume target 500 nm thick 20x20 um2. I attach my input files. I have set PRECISIO as default and also a MULSOPT card, but I have noticed that the results, and error in scored quantities too, are the same both with MULSOPT card enabled and with this card disabled. Moreover, if MULSOPT is enabled simulation time is about 25 ms/primary, whereas if disabled it is 0.05 ms/primary, but there is no difference in results. Is there something wrong in my simulation parameters? Many thanks.
MULS. ENABLED MULS. disabled
xyzDOSE 1.8503E+006 1.8513E+006
xyzDPAsco 2.7045E-013 2.7065E-013
xyzRESniel 3.3533E+003 3.3557E+003
xyzNIELdep 4.4340E+003 4.4372E+003
__________________________________________________________
Giuseppe Prestopino
<
http://web.uniroma2.it> Università di Roma "Tor Vergata"
Dipartimento di Ingegneria Industriale
Via del Politecnico 1
I-00133 Roma, Italy
Tel. <tel:%2B390672597238> +390672597238
<mailto:giuseppe.prestopino_at_uniroma2.it> giuseppe.prestopino_at_uniroma2.it
Received on Tue Nov 25 2014 - 17:56:02 CET