Re: AW: AW: Energy deposition

Dear Dr. Cerutti,
          thank you for solving my problem; I would like to deepen the
point on the use of RADDECAY, however.
I understand that, by not using IRRPROFI and DCYTIMES (so no
RADDECAY), I get GeV/(cm3 primary), while using USRBINs connected to
IRRPROFI and DCYTIMES (and RADDECAY) I get GeV/(cm3 s). But I think
this is what I need: I was interested in estimating the temperature
field in concrete during and after many cycles of irradiation. I can
get it by energy deposition results, but in this case I need not only
immediate results (due only to prompt radiation), but also after long
periods of irradiation (due to decay radiation).
Is it, then, correct if I activate the RADDECAY card, read my results
as GeV/(cm3 s) for the specific time instant of the scoring detector
associated to each USRBIN, then without rescaling them by the beam
current, I have the energy deposition at that specific time? In this
case may I use the default settings for RADDECAY?

My DCYTIMES are also negative, i.e. I want to score also during
irradiation; is in this case the energy deposition due only to
radioactive decay, too? I guess that for negative DCYTIMES
corresponding to the beginning of irradiation profile I get the
results of an istantaneus analysis (that is without using IRRPROFI)
because energy deposition is due to prompt radiation only.

Thank you very much
Sincerely,

Beatrice

At 12.35 27/01/2011, Francesco Cerutti wrote:

>Dear Beatrice,
>
>meaningless negative energy deposition values and infinite statistical
>errors just come from the fact that your USRBIN energy detectors are
>associated to ... undefined cooling times: you input 8 cooling times and
>you ask over the range 13-22.
>
>But I would like to point out a more fundamental misunderstanding. You
>have to bear in mind the distinction between prompt and decay radiation,
>being the latter generated by the (late=not instantaneous) decay of the
>radioactive nuclei produced by the first.
>If you search - as usually - for prompt energy deposition values (indeed
>expressed in GeV/cm3 per beam proton), then irradiation profile and decay
>times are totally unrelevant. You do not need to ask FLUKA to perform the
>radioisotope decay (no need for RADDECAY) and you have to rescale the
>results by the beam current, getting instantaneous power density at
>any time during irradiation.
>On the other hand, by associating the USRBIN energy scoring to a given
>cooling time (referred to the input irradiation profile), you will
>directly get the power density at that time (in GeV/(cm3*s)) *only due to
>the decay (electromagnetic) radiation*.
>
>Ciao
>
>Francesco
>
>**************************************************
>Francesco Cerutti
>CERN-EN/STI
>CH-1211 Geneva 23
>Switzerland
>tel. ++41 22 7678962
>fax ++41 22 7668854
>
>On Thu, 27 Jan 2011, beatrice pomaro wrote:
>
> > Dear Dr. Sommerer,
> > I disabled the Sternheimer and
> > Mat-prop card associated to Material UC2, however
> > I get the same negative energy deposition results
> > and INF values. The error messages you noticed
> > before (me too), are not anymore after disabling the cards, as
> you confirm.
> > But is there another problem in my input file,
> > then? I wonder if it is correct to activate RADDECAY with its default
> > values?
> > Sorry, to ask again
> >
> > Thank you,
> > Beatrice
> >
> >
> > At 18.29 26/01/2011, Sommerer, Florian wrote:
> >> Dear Beatrice,
> >>
> >> When rerunning your simulation I found the
> >> following lines written in the out and err file:
> >>
> >>
> >> *** dp/dx:d,imat,ztar,ij,po,eo -0.00179035082 31 34.6662384
> 1 0.572616202
> >> 1.09920164 ***
> >> *** x,xoster,ccster,d0ster -0.214465268 -0.2191 -6.0247 0. ***
> >> *** dp/dx:d,imat,ztar,ij,po,eo -0.0134390424 31 34.6662384
> 1 0.618808585
> >> 1.12395685 ***
> >> *** x,xoster,ccster,d0ster -0.18077257 -0.2191 -6.0247 0. ***
> >> *** dp/dx:d,imat,ztar,ij,po,eo -0.0225896654 31 34.6662384
> 1 0.668727261
> >> 1.15219403 ***
> >> ***
> >>
> >> Did you observe the same?
> >> I could be wrong but in my opinion these lines
> >> indicate a serious problem in the initialisation
> >> of the stopping power for Uranium dicarbide.
> >> That might be the reason for the negative values in the energy
> deposition.
> >>
> >> You are using Sternheimer parameters and you are
> >> assigning the ionization potential for Uranium
> >> dicarbide according to the values that are
> >> available in the flair data base. This is the recommended way to do it.
> >> However I think exactly there is the problem.
> >> When I omit Sternheimer values and ionization
> >> potential and run again, I don't get the error
> >> messages any more. I think the transport will
> >> still be reasonable without these parameters.
> >>
> >>
> >>
> >> Cheers, Florian
> >>
> >>
> >>
> >>
> >>
> >>
> >> --
> >> Dipl.-Ing. Dr. techn. Florian Sommerer
> >> Physiker
> >> Radiologische Klinik / Heidelberger Ionenstrahl-Therapiezentrum
> >> Florian.Sommerer_at_med.uni-heidelberg.de
> >> Im Neuenheimer Feld 450
> >> 69120 Heidelberg
> >> Germany
> >> -----Urspr=FCngliche Nachricht-----
> >> Von: beatrice pomaro [mailto:pomaro_at_dic.unipd.it]
> >> Gesendet: Mittwoch, 26. Januar 2011 17:14
> >> An: Sommerer, Florian
> >> Betreff: Re: AW: Energy deposition
> >>
> >> Dear Dr. Sommerer,
> >> I had the same problem but I run
> >> flupix-2010 and, by reducing the number of
> >> binning, I had no more problems of stopping because of memory.
> >> I give in attachment the same input file, with
> >> less binning (I kept results requirement after
> >> 1hour, 1year, 10years and 50years from t0,
> >> suitably converted into seconds from the end of
> >> radiation profile), but I have the same problem
> >> of negative values and INF values for energ
> >> deposition (I put, in addition, just the USRBIN34 results).
> >> Many thanks for the support,
> >>
> >> Sincerely,
> >> Beatrice
> >>
> >>
> >> At 09.43 26/01/2011, you wrote:
> >> >Dear Beatrice,
> >> >
> >> > are you sure that you are using the input file you attached to the
> >> >previous mail?
> >> >I tried to rerun it (using FLUKA2008.3d.1) but it stops at
> >> >initialisation due to a lack of memory positions. Which is - I guess -
> >> >due to the big number of binnings you are using.
> >> >Can you please send the right file?
> >> >
> >> >Cheers, Florian
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >--
> >> >Dipl.-Ing. Dr. techn. Florian Sommerer
> >> >Physiker
> >> >Radiologische Klinik / Heidelberger Ionenstrahl-Therapiezentrum
> >> >Florian.Sommerer_at_med.uni-heidelberg.de
> >> >Im Neuenheimer Feld 450
> >> >69120 Heidelberg
> >> >Germany
> >> >-----Urspr=FCngliche Nachricht-----
> >> >Von: owner-fluka-discuss_at_mi.infn.it
> >> >[mailto:owner-fluka-discuss_at_mi.infn.it] Im Auftrag von beatrice pomaro
> >> >Gesendet: Montag, 24. Januar 2011 18:26
> >> >An: fluka-discuss_at_fluka.org
> >> >Betreff: Energy deposition
> >> >
> >> >Dear Fluka users,
> >> > can you please have a look to the input file in attachment:
> >> >the problem is represented by a target made of
> >> >UC2 which is directly impinged by a proton beam (300microA, 70MeV),
> >> >within a concrete target bunker. I used IRRPROFI to model a beam
> >> >working 5000hours/year than stopping, for totally 9years.
> >> >I am interested in the results in terms of energy deposition
> >> >[Gev/(cm3 primary)] on the slice of shielding just in front of the
> >> >target source. However in the USRBIN files I have negative values of
> >> >energy deposition and 'INF' strings.
> >> >Can you address me where the problem is, please?
> >> >If I do not assign an IRRPROFI card for the beam irradiation profile
> >> >does, in this case, the energy deposition correspond to time=3D0?
> >> >
> >> >Many thanks for your help,
> >> >
> >> >Sincerely,
> >> >Beatrice Pomaro
> >
> > **************************************************
> > Ing. Beatrice Pomaro
> >
> > Universita' degli Studi di Padova
> > Dipartimento di Costruzioni e Trasporti
> > via Marzolo, 9 - 35131 Padova (Italy)
> > tel: +39 049 8275605
> > e-mail: pomaro_at_dic.unipd.it
> >
> >
> >
> >

**************************************************
Ing. Beatrice Pomaro

Universita' degli Studi di Padova
Dipartimento di Costruzioni e Trasporti
via Marzolo, 9 - 35131 Padova (Italy)
tel: +39 049 8275605
e-mail: pomaro_at_dic.unipd.it
Received on Thu Jan 27 2011 - 22:00:34 CET