---
**************************************************
Ing. Beatrice Pomaro
Universita' degli Studi di Padova
Dipartimento di Ingegneria Civile, Edile e Ambientale
Via F. Marzolo, 9 - 35131 Padova (Italy)
tel.: +39 049 8275592
e-mail: beatrice.pomaro_at_dicea.unipd.it
Il 22-11-2016 17:31 Joachim Vollaire ha scritto:
> Dear Beatrice
>
> So for the flux you get 2.54 E -04 photons/cm2 per primary using single photons with an energy averaged over the ones of the two Co60 gammas and 5E-04 photons/(cm2 Bq) which seems consistent with the fact that two photons are emitted per decay.
>
> I have used nucleonica, a 8.97e12 Bq source corresponds to an exposure Rate 6.85E+07 µGy/h at 20 cm.
>
> For concrete here is the corresponding attenuation thickness reported by Nucleonica....
>
> Half-Value Shield Thickness(cm) 13.10
>
> Tenth-Value Shield Thickness(cm) 30.53
>
> Cheers
>
> Joachim
>
> FROM: Beatrice Pomaro [mailto:beatrice.pomaro_at_dicea.unipd.it]
> SENT: 19 November 2016 09:51
> TO: Joachim Vollaire <joachim.vollaire_at_cern.ch>
> CC: FLUKA discussion <fluka-discuss_at_fluka.org>; owner-fluka-discuss_at_mi.infn.it
> SUBJECT: RE: [fluka-discuss]: Fwd: Gamma-ray experiment
>
> Dear Joachim and dear Fluka experts,
> thank you for your reply; I checked the results in terms of photon flux at the face of the samples in front of the source by using ISOTOPE in the BEAM card but I can not reach the same value for the photon flux:
>
> - if I use the BEAM card with PHOTONs and the average energy of the gamma rays (1.25MeV) I get 2.5E-4 photons/(cm2 primary) from the USRBIN results in terms of photon flux. Then I multiply it by 7.36E+10 photons/(s kg), which corresponds to the primary flux as checked with Dr. Cerutti in the mail below, and by the sample density (2.398 kg/dm3) and by the sample volume (1dm3) so that I obtain: 4.6E+07 photons/(cm2 s);
>
> - if I use the BEAM card with ISOTOPE I get 5E-04 photons/(cm2 Bq) from the USRBIN results in terms of photon flux. Then I multiply it by the source activity (8.97E+12 Bq) so that I obtain: 4.5E+09 photons/(cm2 s).
>
> Can you explain to me what is wrong, since I find 2 orders of magnitude more photon flux with the ISITOPE sdum, than with the PHOTONs sdum?
> Also, I noticed that in both cases the ratio of the photon flux out and in of the sample leads to an attenuation coefficient of 0.14cm-1 for the sample (ordinary concrete), which corresponds to a half-value thickness of 4.8cm only. Is it realistic? Can you suggest me anything to improve the analysis in case?
>
> Thank you very much for your help,
> Best regards
> Beatrice
>
> ---
>
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
>
> Il 17-11-2016 22:01 Joachim Vollaire ha scritto:
>
> Hi Beatrice
>
> Your assumption is correct, quantities normalized per primary photons with your previous approach are now normalized to one decay : 1 Bq, thus you can use the source activity to compare with your experimental data.
>
> Cheers
>
> Joachim
>
> FROM: Beatrice Pomaro [mailto:beatrice.pomaro_at_dicea.unipd.it]
> SENT: 17 November 2016 11:41
> TO: Joachim Vollaire <joachim.vollaire_at_cern.ch>
> CC: FLUKA discussion <fluka-discuss_at_fluka.org>; owner-fluka-discuss_at_mi.infn.it
> SUBJECT: RE: [fluka-discuss]: Fwd: Gamma-ray experiment
>
> Dear Joachim,
> thank you very much. Does it mean that photon energies and deposited energies are no more per unit primary (photons/s) but per unit activity of the source (Bq), now that the source is modeled via ISOTOPE?
> Shall I multiply by Bq to get [photons/(cm2 s)] or [GeV/(cm3 s)]?
> Thank you in advance
> Best regards,
> Beatrice
>
> ---
>
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
>
> Il 17-11-2016 10:31 Joachim Vollaire ha scritto:
>
> Dear Beatrice
>
> You have to activate the decay in semi-analogue mode :
>
> RADDECAY 2.
>
> You don't need to the DCYTIMES card and you need
>
> DCYSCORE -1. FREF3 FBAR1 1.USRBIN
>
> = -1.0 : if option RADDECAY [1] has been requested with WHAT(1) > 1.0,
>
> i.e. for radioactive decays activated in semi-analogue mode,
>
> the detectors defined by WHAT(4)-WHAT(6) will score both
>
> prompt and radioactive decay particles
>
> Be sure to associate all detectors (including USRBDX) to DCYSCORE.
>
> Il also noticed that you want to see photon fluence spectra with USRBDX. For radioactive decay of isotopes you may want to consider a different energy binning (linear ?) in the 0 few MeV range
>
> USRBDX 99. PHOTON -33. rAir1 rSample2 ABAR2
>
> USRBDX 1. 1E-30 80. &
>
> Hoping this help
>
> Joachim
>
> FROM: Beatrice Pomaro [mailto:beatrice.pomaro_at_dicea.unipd.it]
> SENT: 16 November 2016 17:51
> TO: Joachim Vollaire <joachim.vollaire_at_cern.ch>
> CC: FLUKA discussion <fluka-discuss_at_fluka.org>; owner-fluka-discuss_at_mi.infn.it
> SUBJECT: RE: [fluka-discuss]: Fwd: Gamma-ray experiment
>
> Dear Joachim,
> in replay to your last mail I have considered to use ISOTOPE for the Cobalt 60 source (so by using RADDECAY and DCAYSCORE) as suggested, however with these modifications to the input file, it stops with 'TIME OUT' signal.
> Could you please have a check if the cards associated to the radioactive decay of the source are correct?
> With the introduction of ISOTOPE, does it mean that the USRBIN results (photon flux and deposited energy) must be multiplied by the initial activity of the source and by the duration of the decay times?
> Thank you very much,
> Best regards,
> Beatrice
>
> ---
>
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
>
> Il 19-10-2016 11:01 Beatrice Pomaro ha scritto:
>
> Dear Joachim,
> thank you very much for your reply. The problem with normalization to me is: if I use PHOTONs as primary particles instead of directly simulating the 60Co through ISOTOPE, results should be normalized per [photons/s] correct?
> Do I get this flux rate from the dose and energy of the source _at_ 20cm (where the samples are placed) or the dose and energy exactly at the source?
> I understand that the results are normalized per activity of the source if I use ISOTOPE, instead.
> Thank you in advance,
> Best regards,
> Beatrice
>
> ---
>
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
>
> Il 18-10-2016 17:35 Joachim Vollaire ha scritto:
>
> Dear Beatrice
>
> Maybe a first suggestion (as already mentioned by Francesco) is to use the decay of Co-60 in the source definition (it is more elegant than averaging the two gamma rays) and would allow you to use your source activity for the normalization. Consider the following cards:
>
> BEAM 0.0 ISOTOPE
>
> HI-PROPE 27. 60.
>
> RADDECAY 1.
>
> And don't forget DCYSCORE otherwise you will not get any contribution associated to the decay of Co-60....
>
> DCYSCORE -1.0 0. 0. ***** ***** USRBIN
>
> *
>
> Concerning the transport threshold I would use something lower for electrons (1 MeV is high), what about using 100 keV as for photons....
>
> Could you please reformulate your question on the normalization, not sure I understand properly. You source is calibrated and you know it gives 53 Gy/h _at_ 20 cm ? If this is the case, you should use this value to derive the corresponding Co-60 activity (1 Bq leading to two photons in 99.88 % branching ratio) and use this for normalization all quantities scored with FLUKA.
>
> Looking at analytical codes based on gamma conversion factor, your source strength should be of the order of 6.5 TBq, does it make sense ?
>
> Greetings
>
> Joachim
>
> FROM: owner-fluka-discuss_at_mi.infn.it [mailto:owner-fluka-discuss_at_mi.infn.it] ON BEHALF OF Beatrice Pomaro
> SENT: 13 October 2016 10:56
> TO: Francesco Cerutti <Francesco.Cerutti_at_cern.ch>
> CC: FLUKA discussion <fluka-discuss_at_fluka.org>
> SUBJECT: RE: [fluka-discuss]: Fwd: Gamma-ray experiment
>
> Dear Dr. Cerutti,
> sorry but I'd have another question about the photon flux rate of the experiment with gamma-ray source that I submitted to the forum's attention: since 53 Gy/h is the declared dose at 20cm from the source (in contact with the irradiated concrete sample) shall I use 53Gy/h for the computation below (which leads to 7.668E10 photons/(s kg_concrete) ) or shall I use the dose exactly at the source?
> And should I multiply the photon flux obtained from Fluka (particle/(cm2 primary)) by the same quantity: photons/(s kg_concrete) to get the flux rate: photons/(cm2 s kg_concrete) ?
> In the input file I used NEW-DEFA and card EMFCUT with sdum: PROD-CUT for electron kinetic energy threshold 0.001: GeV and photon production threshold: 0.0001 GeV . Hope it is fine.
> Many thanks for your kind attention,
> Best regards,
> Beatrice
>
> ---
>
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
>
> Il 09-10-2016 23:07 Francesco Cerutti ha scritto:
>
> actually the average gamma energy is 1.25 MeV, giving 7.36E10 photons/(s kg)
>
> On Sun, 9 Oct 2016, Francesco Cerutti wrote:
>
> Dear Beatrice,
>
> fine with the first point. Then, when one divides by 1.2 MeV transformed into J [assuming the all energy is absorbed in the sample], the result is 7.668E10 photons/(s kg), to be multiplied by the sample mass [assuming an uniform irradiation].
> I understand that you already multiplied by the concrete density and are left with the volume normalization, that's correct.
>
> Kind regards
>
> Francesco
>
> **************************************************
> Francesco Cerutti
> CERN-EN/STI
> CH-1211 Geneva 23
> Switzerland
> tel. ++41 22 7678962
> fax ++41 22 7668854
>
> On Sun, 9 Oct 2016, Beatrice Pomaro wrote:
>
> Dear Dr. Cerutti,
>
> thank you very much for your explanation. I agree with you in the
> definition of the
> energy deposition in a volume. Also I am using PHOTONs as primary
> particle, yes.
> If I want to compute the photon rate, the 60Co source working at
> 53Gy/h=0.01472
> Gy/s and 1.2MeV, shall I transform 0.01472 Gy/s into 0.01472 W/kg where
> this
> quantity is per kg of the concrete sample placed around the source (to be
> tested),
> is it correct?
> Then I need to divide it for the electronic charge (1.6*10-19 C) and the
> energy of
> the gamma rays (1.2*10+6 eV) so to obtain: 1.92*10+8 photons/(cm3 s) where
> cm3 is
> the volume of the concrete sample?
> Is it correct?
> Thank you in advance,
> Best regards,
> Beatrice
>
> ---
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
>
> Il 07-10-2016 19:17 Francesco Cerutti ha scritto:
>
> Dear Beatrice,
>
> I miss the expected meaning of GeV/(cm2 s). Energy is deposited in a
> volume and with a cartesian or cylindrical USRBIN [*not* with a
> USRBIN
> per region] you get GeV/(cm3 primary) as you wrote. Multiplying by
> the
> photon rate (I assume you decided to use PHOTONs as primary
> particles
> instead of directly simulating the 60Co decay through ISOTOPE), you
> will get power deposition density (that can be expressed in W/cm3)
> and
> I would be pretty happy with that, with no need for a further
> manipulation by an ill-defined quantity.
> Do not hesitate to come back with your thoughts if in fact you turn
> out
> not to be happy.
>
> Cheers
>
> Francesco
>
> **************************************************
> Francesco Cerutti
> CERN-EN/STI
> CH-1211 Geneva 23
> Switzerland
> tel. ++41 22 7678962
> fax ++41 22 7668854
>
> On Thu, 6 Oct 2016, Beatrice Pomaro wrote:
>
> Dear Anton,
> thank you very much for your advice, may I ask you also about the output
> results of a USRBIN score? We read in fact from the manual: "The results
> from USRBIN are normalised per unit volume and per unit primary weight,"
> does it mean that for energy deposition in order to get GeV/(cm2 s) out of
> GeV/(cm3 primary) one needs to multiply Fluka result by the particle flux
> (particle/s) and the length in direction orthogonal to the flux of the
> region of interest for the scoring?
> Thank you in advance for your explanation,
> Best regards,
> Beatrice
>
> Il 27-09-2016 15:49 Anton Lechner ha scritto:
>
> Dear Beatrice,
>
> Running your input file, one gets following error message:
>
> *** Too many terms in parenthesis expansion ***
> *** Execution terminated ***
>
> I think the message is quite self-explaining. The issue lies in
> the definition of the second zone of the rAir region. As a good
> practice, I would try not to use too many parenthesis (you can
> equally define the geometry without using any parenthesis at
> all). Also note that if you have too many bodies in a zone
> definition this can also slow down the simulation. It is better
> to have more zones with fewer bodies than to have one zone with
> many bodies.
>
> Besides, on the EMFCUT card you set the production cuts for
> e-/e+ and photons to 0. Note that physics models are no longer
> applicable at very low energies and one should respect the
> minimum values recommended in the manual. I quote:
> "The minimum threshold energy for transport and production of
> photons is 100 eV. For electrons and positrons, it is 1 keV."
>
> Cheers, Anton
>
> ____________________________________________________________________________
> From: owner-fluka-discuss_at_mi.infn.it
> [owner-fluka-discuss_at_mi.infn.it] on behalf of Beatrice Pomaro
> [beatrice.pomaro_at_dicea.unipd.it]
> Sent: 27 September 2016 15:00
> To: fluka-discuss
> Subject: [fluka-discuss]: Fwd: Gamma-ray experiment
>
> Dear Fluka experts,
> I am trying to reproduce an irradiation experiment due to gamma-rays
> from a Cobalt60 source.
> I am using Flair. I can not run the input file because the 001.out
> file stops before reading regions, while the file .out gives a
> generic error message (that I am reporting here below):
>
> Dir: /home/flupix/Desktop/Prova
> Cmd: /usr/bin/nohup /usr/local/fluka/flutil/rfluka -e
> /home/flupix/Desktop/Prova/Prova.flair -M 2 Prova
> $TARGET_MACHINE = Linux
> $FLUPRO = /usr/local/fluka
>
> Initial seed copied from /usr/local/fluka
> Running fluka in /home/flupix/Desktop/Prova/fluka_2030
>
> ======================= Running FLUKA for cycle # 1
> =======================
> /usr/local/fluka/flutil/rfluka: line 359: 2058
> Aborted (core dumped) "${EXE}" < "$INPN" 2> "$LOGF" >
> "$LOGF"
>
> No .err files are produced yet, since the analysis stops before.
> I am attaching here my input file. Would you tell me what I am doing
> wrong, please?
> Thank you in advance,
> Best regards,
> Beatrice Pomaro
>
> --
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
> --
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
>
> --
> **************************************************
> Ing. Beatrice Pomaro
>
> Universita' degli Studi di Padova
> Dipartimento di Ingegneria Civile, Edile e Ambientale
> Via F. Marzolo, 9 - 35131 Padova (Italy)
> tel.: +39 049 8275592
> e-mail: beatrice.pomaro_at_dicea.unipd.it
Links:
------
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