RE: tab.lis file different to plot, what are the correct units

Dear Francesco and Joachim,

Thankyou both for your responses. I understand better now.

Just one query, why is what 6 in the first card for usryield named norm
and not area in FLAIR?

So to confirm if I choose plain double differential yield in my usryield
card and choose energy and momentum as dx1 and dx2 and enter nothing in
what 6 on the first card then I get units of [GeV*primary*(GeV/c)]**-1

If I multiply each value in the tab.lis file by the width of the
corresponding energy bin and the width of the single momentum bin then I
have units of [primary]**-1 which is what I am hoping to get. Sorry if
this seems really basic, but well it is quite important for us that
there are no mistakes as these results are influencing design decisions
on a future target station.

Thanks again for your help.

Best Regards
Tristan

-----Original Message-----
From: owner-fluka-discuss_at_mi.infn.it
[mailto:owner-fluka-discuss_at_mi.infn.it] On Behalf Of Francesco Cerutti
Sent: 12 May 2010 08:58
To: Joachim Vollaire
Cc: Davenne, Tristan (STFC,RAL,EID); fluka-discuss_at_fluka.org
Subject: RE: tab.lis file different to plot, what are the correct units

Dear Tristan,

if you choose to score as a function of energy and angle and select, as=20
usually, the plain double differential yield (WHAT(6) in the=20
continuation card), then in the tab.lis file (as well as in the sum.lis)

you will get values in [(GeV*primary*cm2*sr)**-1] as you wrote, provided

that you input the scoring boundary area (in WHAT(6) on the first card).

In Flair, you are free to plot different things. If you select to plot
"Y"=20
in the Y menu, you will get exactly the file values and nothing else.=20
However, the Y default is "Y * <Xgeo>", where <Xgeo>=3Dsqrt(Emin*Emax),
i.e.=20
the geometric mean as specified in the X menu. This is especially
intended=20
for lethargy plot, where you have a logarithmic scale on X (=3DE, energy =

axis) and plot dA/d(log(E))=3DE*dA/dE. So I guess you left the default=20
choice and got the file values multiplied by sqrt(Emin*Emax). Note that=20
the default choice for many purposes makes no sense.

Ciao

Francesco

**************************************************
Francesco Cerutti
CERN-EN/STI
CH-1211 Geneva 23
Switzerland
tel. ++41 22 7678962
fax ++41 22 7668854

On Tue, 11 May 2010, Joachim Vollaire wrote:

> Dear Tristan
>
> I think that the conversion factor between what is being plotted by
> flair (what you see on gnuplot) and the numerical value in the output
> file is equal to (Emax-Emin)*(log (Emax-Emin) ), where Emax and Emin
are
> respectively the higher and lower boundaries of each bin. Please check
> and let me know if this does not explain the difference you are
> observing. Hope it helps.
> Joachim
>
> ________________________________
>
> From: owner-fluka-discuss_at_mi.infn.it on behalf of
tristan.davenne_at_stfc.ac.uk
> Sent: Tue 4/27/2010 4:07 PM
> To: fluka-discuss_at_fluka.org
> Subject: tab.lis file different to plot, what are the correct units
>
> Hi,
>
> I have used a usryield scoring card to try and calculate pion+/- yield
> from a target. I used usryield because I want to make a cut in
> transverse momentum (only score pions that have a transverse momentum
> below 0.5GeV/c) with energies in a defined range. I have specified
> 13bins in the energy range between 1.5GeV and 8GeV, i.e. 0.5GeV bin
> width.
>
> I looked at the tab.lis file that is created and I also plotted the
> result using FLAIR and gnuplot. I found that the numbers in the plot
> were higher than the values in the tab.lis file. I then found that the
> numbers in the plot are a transformation of the numbers in the file.
> Each number in the file has been multiplied by the energy in the
centre
> of the bin.
>
> I have not multiplied by the surface area of the target or 2pi() at
this
> stage. Does that mean the numbers in the file have units of
> pions/GeV/primary/cm2/sr and the numbers on the graph have units of
> pions/primary/cm2/sr? I would appreciate confirmation on these units
> from an expert as I was a little surprised to find the numbers in the
> tab.lis file were different to the numbers on the plot.
>
> I attach my input file if that is of any help.
>
> Many Thanks
>
> Tristan
>
> Tristan Davenne
> STFC Technology
> G19 R65
> Rutherford Appleton Laboratory
> Chilton, Didcot, Oxfordshire OX11 0QX, UK
> Tel: +44 (0)1235 445485
> Email: tristan.davenne_at_stfc.ac.uk <mailto:t.r.davenne_at_rl.ac.uk>
>
>

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