Re: Differences in Flux and Dose Equivalent Errors in USRTRACK

Alberto,

Many thanks for your response. Apologies for my delay, I have been on holiday
for a short while.

In my AUXSCORE I have used WHAT(2) = Neutron and SDUM = AMB74. My USRTRACK,
WHAT(2) was DOSE-EQ. I have attached my input file. I would have expected
31.sum.lis and 41.sum.lis to have the same standard deviations given that
they should be the same results, albeit with the latter having flux-dose
conversion factors applied. However they do not have the same standard
deviations. I have attached the input file as suggested,

Many thanks again!
Lewis.

-----Original Message-----
From: owner-fluka-discuss_at_mi.infn.it [mailto:owner-fluka-discuss_at_mi.infn.it] On Behalf Of Alberto Fasso'
Sent: 21 April 2011 21:21
To: fluka-discuss_at_fluka.org; Macfarlane, Lewis
Subject: Re: Differences in Flux and Dose Equivalent Errors in USRTRACK

Lewis,

in your USRTRACK detector, did you put WHAT(2)=DOSE-EQ?
in your AUXSCORE card, did you put WHAT(2)=NEUTRON and SDUM=AMB74,
or WHAT(2) blank and SDUM=AMB7?
In the second case, you would get dose equivalent for all particles,
as you suggest.

But it is always difficult to answer questions if the user doesn't send the
input file

Alberto

On Thu, 21 Apr 2011, Macfarlane, Lewis wrote:

> Dear Experts,
>
> In a recent FLUKA case I have undertaken, I've scored both neutron
> fluence and neutron dose equivalent in the same geometry region, using
> USRTRACK.
>
> I have used two separate USRTRACK cards with different names. The first
> scores neutron fluence. The second scores dose equivalent and applies
> AMB74 flux-dose conversion factors for neutrons only through an AUXSCORE
> card. I ran the case for 10 cycles, 1.e7 primary particles per cycle.
> The sources is a proton beam with a rectangular spectrum, energy range
> 190-210 MeV.
>
> Upon viewing the results, I noticed that the 2 USRTRACKS had very
> different associated standard deviations when I would expect that
> neutron fluence and neutron dose equivalent should have the same
> standard deviation as the only difference is the application of
> fluence-dose equivalent conversion coefficients! Can anyone tell me the
> reason why this is the case? I'm suspecting maybe the standard deviation
> in the dose equivalent output is in fact for all particles, whereas the
> result has been filtered for neutrons only, is =
> this the case?
>
> Many thanks,
> Lewis MacFarlane.