From: Alberto Fasso' (fasso@SLAC.Stanford.EDU)
Date: Mon Oct 22 2007 - 09:47:45 CEST
Dear Mary,
there are "electromagnetic showers" (or cascades) and "hadronic showers"
(or cascades). Often, if not specified, people mean electromagnetic, as you
did. But in general one speaks of showers or cascades only at high energies
(higher than 1 GeV, let's say). I have the impression that in your
message you were talking about gammas in the MeV energy range.
Regards,
Alberto
On Sat, 20 Oct 2007, me@marychin.org wrote:
> Dear Alberto,
>
> Thanks for pointing out my used of the term, 'radiation showers'. I reali=
sed=20
> that I used the term losely -- partly due to my earlier exposure to=20
> e+/e-/photons (started to work with heavier particles only much later) --=
no=20
> excuse though. I must be careful next time and would like to be sure that=
I=20
> understand correctly at this point: do radiation showers apply to=20
> electromagnetic ones only? How about 'cascade'?
>
> Thanks very much,
> mary
>
>
> -------------------------------------------------------------------------=
-------
> From: Alberto Fasso' [mailto:fasso@slac.stanford.edu]
> Sent: Mon 10-Sep-07 09:47
> To: me@marychin.org
> Cc: fluka-discuss@fluka.org
> Subject: Re: individual isotope
>
>
> Dear Mary,
>
> (g,n) and (n,g) reactions are different on different nuclei, so you can e=
xpect
> to get different results concerning nuclear effects (e.g., neutron yield,
> residual nuclei). On the other hand, "radiation showers" (you are meaning
> electromagnetic showers, I guess) depend on the charge (Z) but very littl=
e on
> the mass (A) of the nuclei: so it is no surprise that you don't see any
> difference.
> And even (g,n) reactions have a very weak dependence on A, that cannot gi=
ve
> substantial differences between A =3D 63 and 65, which differ by less tha=
n 2%.
> Concerning (n,g) reactions, perhaps one could expect some differences
> in the production of residual nuclei between Cu-63 and Cu-65: but the
> present neutron library of FLUKA contains only natural copper (see Chap. =
10
> of the manual). In the new library which is just now in preparation,
> also the two individual isotopes will be available (probably near the end=
of
> this year).
>
> Alberto
>
> On Sat, 8 Sep 2007, me@marychin.org wrote:
>
>> Hi.
>>
>> I ran 3 separate simulations containing the following lines respectively=
:
>> MATERIAL 29 62.9296 1. 26.0 63. CO=
PPER
>> MATERIAL 29 63.546 1. 26.0 CO=
PPER
>> MATERIAL 29 64.928 1. 26.0 65. CO=
PPER
>>
>> I'm looking for (g,n) and (n,g) reactions, and expected the 3 simulation=
s to
>> produce different radiation showers. However, I've got identical showers=
from
>> the three. Could someone please help?
>>
>> Thanks,
>> mary
>
>
--=20
Alberto Fass=F2
SLAC-RP, MS 48, 2575 Sand Hill Road, Menlo Park CA 94025
Phone: (1 650) 926 4762 Fax: (1 650) 926 3569
fasso@slac.stanford.edu
--1334195030-1495511423-1193039265=3D:8619--
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