RE: [fluka-discuss]: USRYIELD two-way vs. one-way

From: Francesco Cerutti <Francesco.Cerutti_at_cern.ch>
Date: Thu, 27 Mar 2014 14:29:19 +0100

> I believe what you are saying is the difference between the WHAT(6) code
> in the second line...the 1006 vs. 1003 designation? Right? In the past,
> I've used the plan double differential (i.e. xx03) and that was why I
> was getting a difference.

Exactly

> I was also wondering why it didn't matter on the material selection in
> the case when I used the 1/cos term.

The material selection just impacts LET calculation (in the sense that,
irrespective of the actual material in the geometry, you can ask the
code to score as a function of LET in water, as typical example) and
scaling from yield to cross section (in the sense that the computed yield
is multiplied by the microscopic inelastic cross section of BEAM particles
on nuclei of the selected material)

Cheers

Francesco

> -----Original Message-----
> From: Francesco Cerutti [mailto:Francesco.Cerutti_at_cern.ch]
> Sent: Wednesday, March 26, 2014 6:29 PM
> To: REDDELL, BRANDON D. (JSC-EV511)
> Cc: fluka-discuss_at_fluka.org
> Subject: RE: [fluka-discuss]: USRYIELD two-way vs. one-way
>
>
> Dear Brandon,
>
> in order to separate entering and exiting particles you have to ask for plain double differential yield, which is a *current* scoring. Also in real life such a separation is achievable only when you measure a directional current. You asked instead for fluence, which is most often the relevant quantity (see the famous thread http://www.fluka.org/web_archive/earchive/new-fluka-discuss/0543.html),
> though it is not USRYIELD the typical card to score it. In that case, the code, as reality, does not distinguish between entering and exiting particles, giving the total tracklength density.
>
> USRBDX is a different story, since there one-way scoring is a specific option made available in addition to two-way scoring, both for current and fluence.
>
> (Note that your material selection in USRYIELD is in fact immaterial, since you are not asking for LET scoring, nor for cross section
> normalization)
>
> Ciao
>
> Francesco
>
> **************************************************
> Francesco Cerutti
> CERN-EN/STI
> CH-1211 Geneva 23
> Switzerland
> tel. ++41 22 7678962
> fax ++41 22 7668854
>
> On Mon, 17 Mar 2014, REDDELL, BRANDON D. (JSC-EV511) wrote:
>
>>
>> Hi Mary,
>>
>>  
>>
>> I am finally back at my office where I have access to FLAIR and SimpleGeo.
>> I¢m sorry to keep bugging you on this, but I am not replicating your
>> information below with respect to USRYIELD.
>>
>>  
>>
>> In the below cards that you edited, you used code 2374 in the WHAT(1)
>> column for the forward direction (Bod1->Bod2) and tabulated the
>> neutron and proton fluxes using the polar angle in degrees as the 2nd
>> variable, however, for the backwards direction (the 2nd two USRYIELD
>> CARDs) you used the same code
>> 2374 but left my original settings for using particle charge instead
>> of polar angle (-0.5 to 0.5 for neutrons, and 0.5 to 1.5 for protons).
>> If those are indeed the inputs you ran, then of course the USRYIELD
>> results in files
>> 21-24 will all be different. Is this what you really did or am I
>> misunderstanding your response?
>>
>>  
>>
>> Also, I did find the extra 0.0 in my input geometry files, however
>> correcting them made no change. I wouldn¢t expect it to in this case
>> since both numbers bounded my geometry of my target (i.e. if FLUKA
>> reads to the first decimal place, get same result). I¢ve cleaned up
>> the test file and I have no errors in my FLUKA run, not any in FLAIR,
>> and none listed by SimpleGEO. In this simple case, can you or somebody
>> else tell my why USRYIELD is giving the same result for forward and
>> backward differential flux? As I mentioned in another email, I have
>> used USRYIELD many times and haven¢t had a problem like this before. I
>> would prefer to use USRYIELD so that I can swap out the codes to score other quantities.
>>
>>  
>>
>> I appreciate your help and feedback.
>>
>>  
>>
>> Brandon
>>
>>  
>>
>>  
>>
>> From: me_at_marychin.org [mailto:me_at_marychin.org]
>> Sent: Thursday, March 13, 2014 1:13 AM
>> To: REDDELL, BRANDON D. (JSC-EV511)
>> Cc: fluka-discuss_at_fluka.org
>> Subject: RE: [fluka-discuss]: USRYIELD two-way vs. one-way
>>
>>  
>>
>> Hi Brandon,
>>
>>  
>>
>> As pointed out earlier, the following are not something we should
>> expect FLUKA to digest:
>>
>> - numbers 100.0000.0 and 50.000.0
>>
>> - USRBDX scoring from angle zero to angle zero in zero bin
>>
>>  
>>
>> In addition to the above which FLAIR flashes in red, I modified as
>> follow, since you still haven't divulged what you've been trying to score:
>>
>> $ grep ^USR brandon.inp
>>
>> USRYIELD 2374. NEUTRON 21. BOD1 BOD2 1.0Nu35 USRYIELD 2.5 1.0E-14 1.
>> 180. 0.0 1006. & USRYIELD 2374. PROTON 22. BOD1 BOD2 1.0Pr35 USRYIELD
>> 2.5 1E-14 1. 180. 0.0 1006. & USRYIELD 2374. NEUTRON 23. BOD2 BOD1
>> 1.0Nu35b USRYIELD 2.5 1.0E-14 1. 0.5 -0.5 1006. & USRYIELD 2374.
>> PROTON 24. BOD2 BOD1 1.0Pr35b USRYIELD 2.5 1.0E-14 1. 1.5 0.5 1006. &
>> USRBDX -1.0 NEUTRON 25. BOD1 BOD2 N1c USRBDX 2.5 1E-14 1. 1. & USRBDX
>> -1. NEUTRON 26. BOD2 BOD1 N1f USRBDX 2.5 1E-14 1. 1. & USRBDX 9.
>> NEUTRON 27. BOD1 BOD2 N2c USRBDX 2.5 1E-14 1. 1. & USRBDX 9. NEUTRON
>> 28. BOD2 BOD1 N2f USRBDX 2.5 1E-14 1. 1. &
>>
>> The change of fortran output units is only for the convenience which
>> follows:
>>
>> Results: there is no symmetry in one-way scoring whether in USRYIELD
>> or USRBDX. The only symmetry is in USRBDX two-way scoring:
>>
>> $ ls brandon001_fort.2[1-4] | while read f; do echo -n $f; tail -n 1
>> $f ; done
>> brandon001_fort.21 2.9876E-03
>> brandon001_fort.22 3.2540E-02
>> brandon001_fort.23 0.0000E+00
>> brandon001_fort.24 1.8812E+00
>>
>> $ ls brandon001_fort.2[5-8] | while read f; do awk 'NR==19{print
>> FILENAME,$0}' $f ; done
>> brandon001_fort.25 1.1459E-03
>> brandon001_fort.26 6.3662E-05
>> brandon001_fort.27 6.0479E-04
>> brandon001_fort.28 6.0479E-04
>>
>> There is indeed mis-positioning of spaces in the above .inp excerpt I
>> pasted inline, which is good to prevent further cut-and-paste at this
>> point ;)
>>
>> Mis-positioning of spaces, however, was obviously not an issue when I
>> recommended the three steps for solving your problem.
>>
>> :) mary
>>
>>  
>>
>> On 11 March 2014 at 09:31 "REDDELL, BRANDON D. (JSC-EV511)"
>> <brandon.d.reddell_at_nasa.gov> wrote:
>>
>> Hi Mary,
>>
>>  
>>
>> I think perhaps the input CARD items below (in the email) got
>> shifted in the email. In a separate email, I sent an attached
>> input file that runs in FLUKA. I am trying to score the proton
>> and neutron flux across a plane in the solid. I use USRYIELD all
>> the time and it works usually.  For the USRYIELD cards, there is
>> not angular binning. I am obtaining the differential flux in
>> energy of protons or neutrons. The second differential is over
>> charge. The simulation works fine and the results look good
>> compared with other codes. The only problem is that forward and
>> backward fluxes are exactly the same.
>>
>>  
>>
>> As for the USRBDX cards, I added those to the input file for
>> comparison to see if they give the same for 1-way and 2-way
>> scoring.  They do as well. Have you had a chance to look at that
>> file?
>>
>>  
>>
>> Brandon
>>
>>  
>>
>>  
>>
>> From: me_at_marychin.org [mailto:me_at_marychin.org]
>> Sent: Monday, March 10, 2014 11:33 PM
>> To: fluka-discuss_at_fluka.org; REDDELL, BRANDON D. (JSC-EV511)
>> Subject: RE: [fluka-discuss]: USRYIELD two-way vs. one-way
>>
>>  
>>
>> Brandon,
>>
>> Both of your input files appear to contain multiple errors, including
>> numerical formats and the request for zero angular binning from omega
>> zero to omega zero. What are you trying to score? Have you checked
>> with FLAIR? Did FLUKA actually run?
>>
>> On 09 March 2014 at 22:12 "REDDELL, BRANDON D.
>> (JSC-EV511)" <brandon.d.reddell_at_nasa.gov> wrote:
>>
>> My expectation was that switching the upstream and
>> downsteam assignments will give forward or backward
>> USRYIELD distributions. I have a simple slab, a proton
>> beam normally incident and I am looking at the
>> differential flux of neutrons crossing the surface. I have
>> the following USRYIELD CARDS for the forward flux of
>> neutrons and the backward flux of neutrons between two
>> adjacent bodies. The two files are exactly the same?  I
>> haven¢t seen this before in previous versions of FLUKA, so
>> I am wondering if I am doing something wrong. My source is
>> a beam of protons normally incident on a slab surface. I
>> must be overlooking something very simple here?
>>
>>  
>>
>> RPP BLKH -500000.0 500000.0 -500000.0 500000.0 -500000.0
>> 100.0000.0
>>
>> RPP SPCE -50000.0 50000.0 -50000.0 50000.0 -50000.0
>> 50.000.0
>>
>> RPP TARG  -5000.0 500.0 -5000.0 5000.0 0.0 14.9
>>
>> XYP    P1 12.967766
>>
>> XYP    P2 14.820304
>>
>>   END
>>
>> BLKH     5  +BLKH -SPCE
>>
>> SPCE     5  +SPCE -TARG
>>
>> BOD1     5  +TARG +P1
>>
>> BOD2     5  +TARG +P2 -P1
>>
>> BOD3     5  +TARG -P2
>>
>>   END
>>
>> GEOEND
>>
>> *
>>
>> ASSIGNMA    BLCKHOLE      BLKH
>>
>> ASSIGNMA      VACUUM      SPCE
>>
>> ASSIGNMA    ALUMINUM      BOD1
>>
>> ASSIGNMA    ALUMINUM      BOD2
>>
>> ASSIGNMA    ALUMINUM      BOD3
>>
>> * Forward
>>
>> USRYIELD        2174   NEUTRON     -50.0      BOD1     
>> BOD2       1.0Nu35
>>
>> USRYIELD         2.5    1.0D-5      50.0       0.5     
>> -0.5      1006&
>>
>> * Backward
>>
>> USRYIELD        2174   NEUTRON     -60.0      BOD2     
>> BOD1       1.0Nu35
>>
>> USRYIELD         2.5    1.0D-5      50.0       0.5     
>> -0.5      1006&
>>
>> *
>>
>> From: me_at_marychin.org [mailto:me_at_marychin.org]
>> Sent: Sunday, March 09, 2014 8:46 PM
>> To: fluka-discuss_at_fluka.org; REDDELL, BRANDON D.
>> (JSC-EV511)
>> Subject: Re: [fluka-discuss]: USRYIELD two-way vs. one-way
>>
>>  
>>
>> Hi Brandon,
>>
>> Swapping the upstream and downstream regions generally would not
>> produce the same results. Is there any corresponding symmetry of some
>> sort in your set up?
>>
>> Cheers,
>>
>> mary
>>
>> On 08 March 2014 at 05:35 "REDDELL, BRANDON D.
>> (JSC-EV511)" <brandon.d.reddell_at_nasa.gov> wrote:
>>
>> Hello,
>>
>>  
>>
>> I recently performed a simulation and used the
>> USRYIELD card to get the double differential
>> spectrum crossing a boundary defined by reg1 and
>> reg2. I swapped the upstream and downstream
>> assignments in WHAT(4) and WHAT(5) expecting
>> different results to get both forward and backward
>> estimates. I got the same results in both cases. Can
>> someone tell me if this is the expected result? In
>> the past, I was under the impression that it would
>> give me forward or backward double differential
>> scoring and not just the total.
>>
>>  
>>
>> I am aware that I can use USRBDX to do this same
>> problem.
>>
>>  
>>
>> Thanks,
>>
>>  
>>
>> Brandon
>>
>>
>>  
>>
>>
>>  
>>
>>
>>  
>>
>>
>>
>
Received on Thu Mar 27 2014 - 15:42:18 CET

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