...Besides that. Using the Pencil beam and a single 'large' bin in the
USRBIN you might obtain results which are going to be averaged on the
target and will only partially indicative of the real DPA, DOSE and NIELs
you get where the beam is impinging.
Vittorio
On Sun, Nov 30, 2014 at 5:21 PM, Vittorio Boccone <
dr.vittorio.boccone_at_ieee.org> wrote:
> Caro Giuseppe,
> in fact your comparison is not indicative as the result with errors
> should be compared for equivalent execution times.
>
> Second I realized you just one bin in the USRBIN having at the same time a
> pencil beam (dimensionless) which will help you clearly in having the value
> you want with fewer primaries.
>
> I'm not sure anymore biasing the decaying products (LAM-BIAS) will help
> you more in case you care interested in having just one number out of the
> simulation.
>
> Best
> V.
>
>
> On Tue, Nov 25, 2014 at 4:32 PM, Giuseppe Prestopino <
> giuseppe.prestopino_at_uniroma2.it> wrote:
>
>> 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" <http://web.uniroma2.it>
>>
>> Dipartimento di Ingegneria Industriale
>>
>> Via del Politecnico 1
>>
>> I-00133 Roma, Italy
>>
>> Tel. +390672597238
>>
>> giuseppe.prestopino_at_uniroma2.it
>>
>>
>>
>> *Da:* Vittorio Boccone [mailto:dr.vittorio.boccone_at_ieee.org
>> <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
>>
>> Università di Roma "Tor Vergata" <http://web.uniroma2.it>
>>
>> Dipartimento di Ingegneria Industriale
>>
>> Via del Politecnico 1
>>
>> I-00133 Roma, Italy
>>
>> Tel. +390672597238
>>
>> giuseppe.prestopino_at_uniroma2.it
>>
>>
>>
>>
>>
>
>
Received on Sun Nov 30 2014 - 23:21:52 CET