Dear Marius,
the reason why you get some activation from your deuteron beam is that you
switched on electromagnetic dissociation. However, as commented before,
your simulation is not reliable because the nuclear interaction
contribution, which is the main one, is not there.
As a side note, PAIRBREM is not really relevant as well as electronuclear
reactions, which by the way are actually not available at all in the
distributed version (there is no mention of them in the manual, although
the Flair menu already embeds this option).
Best regards
Francesco
**************************************************
Francesco Cerutti
CERN-EN/STI
Esplanade des Particules 1
1211 Geneva 23
Switzerland
tel. +41 22 7678962
On Mon, 28 Oct 2019, Marius Arenz wrote:
> Dear Francesco,
>
> no, I don't have the ionsplit card activated. The alloy does not contain
> hydrogen but some other elements (obviously). I'll attach the input file and
> the residual nuclei. (Please note that the comment of the beam card contains
> wrong information)
>
> Best regards
> Marius
>
>
> On 24.10.19 18:36, Francesco Cerutti wrote:
>>
>> Hi Marius,
>>
>> they are definitely tracked down to their transport threshold. Moreover,
>> there is the possibility to split them into one neutron and one proton at
>> their interaction point computed by the code. This artificial splitting
>> 'reaction' can be activated by the card
>>
>> PHYSICS 1. 0.005 0.15 2.0 2.0
>> 3.IONSPLIT
>>
>> as documented in the manual.
>>
>> For the mentioned 28 MeV deuteron beam, do you have hydrogen in your
>> Al-alloy? Or the above card?
>>
>> Best wishes
>> Francesco
>>
>> **************************************************
>> Francesco Cerutti
>> CERN-EN/STI
>> Esplanade des Particules 1
>> 1211 Geneva 23
>> Switzerland
>> tel. +41 22 7678962
>>
>> On Thu, 24 Oct 2019, Marius Arenz wrote:
>>
>>> Dear Francesco, dear Kriti
>>>
>>> thanks for the quick replies. This explains a lot. For me, three
>>> questions remain:
>>> - What happens to secondary deuterons that are produced during nuclear
>>> reactions? Are these not tracked at all if they have a lower energy than
>>> 200 MeV?
>>> - In a simulation of deuterons (28 MeV) on a Al-alloy, I get results in
>>> form of radioactive nuclei. What is Fluka doing? Where do they come from?
>>> - Is support for deuterons planned in the future?
>>>
>>> Best regards
>>> Marius Arenz
>>>
>>> On 24.10.19 17:06, Francesco Cerutti wrote:
>>>>
>>>> Dear all,
>>>>
>>>> note that (low energy) deuteron interactions are simply not
>>>> implemented,
>>>> as formerly recalled:
>>>> http://www.fluka.org/web_archive/earchive/new-fluka-discuss/8921.html
>>>>
>>>> At higher energies, they are crudely performed by the rQMD module in
>>>> its
>>>> application range, i.e. above 200 MeV deuteron energy.
>>>>
>>>> Kind regards
>>>>
>>>> Francesco
>>>>
>>>> **************************************************
>>>> Francesco Cerutti
>>>> CERN-EN/STI
>>>> Esplanade des Particules 1
>>>> 1211 Geneva 23
>>>> Switzerland
>>>> tel. +41 22 7678962
>>>>
>>>> On Thu, 24 Oct 2019, Kriti Gupta wrote:
>>>>
>>>>> Hi Marius,
>>>>>
>>>>> In your RESNUCLE card, you have not specified WHAT(3), that is the
>>>>> max. Z
>>>>> for the activated nuclei. Default is max. Z of all elements in the
>>>>> system, which in your case is Z=7. To get activation for O and F
>>>>> products, you need to have atleast Z=9.
>>>>>
>>>>> Hope it helps.
>>>>>
>>>>> Best regards,
>>>>> Kriti Gupta
>>>>>
>>>>> -----Original Message-----
>>>>> From: owner-fluka-discuss_at_mi.infn.it <owner-fluka-discuss_at_mi.infn.it>
>>>>> On
>>>>> Behalf Of Marius Arenz
>>>>> Sent: 24 October 2019 14:49
>>>>> To: fluka discuss <fluka-discuss_at_fluka.org>
>>>>> Subject: [fluka-discuss]: Deuteron activation of N
>>>>>
>>>>> Dear Fluka users,
>>>>>
>>>>> I am using Fluka for simulations of activation in various particle
>>>>> beams.
>>>>> At the moment, I am particularly interested in the activation of air.
>>>>> I
>>>>> used 14 MeV proton, 28 MeV deuteron and 56 MeV alpha beams for my
>>>>> simulations. While obtaining reasonable results for protons and
>>>>> alphas,
>>>>> the result for deuterons was no activation at all. This result is in
>>>>> contrast to my expectations and to cross section values given e.g.
>>>>> here:
>>>>> http://www.oecd-nea.org/janisweb/
>>>>> for e.g. deuteron induced reactions like N14 (d,n) O15, C12 (d,n) N13
>>>>> or
>>>>> O16 (d,n) F17 just to name a few. All these cross sections differ
>>>>> significantly from zero for deuteron energies below 28 MeV.
>>>>>
>>>>> I am not a long-term Fluka user and I was not able to find the mistake
>>>>> in
>>>>> my input file, hence, I decided to ask this question to the mailing
>>>>> list.
>>>>>
>>>>> To give a minimal example, I have simplified the geometry and setup to
>>>>> a
>>>>> deuteron irradiation of Nitrogen in a 4 m cylindrical black hole
>>>>> container. The four metre length should allow for all deuterons to be
>>>>> stopped. From the cross sections I would at least expect the N14 (d,n)
>>>>> O15 reaction to happen and produce a significant amount of F17.
>>>>> What I get is a small amount of 11C with an uncertainty of 99% despite
>>>>> 40 cycles with 10^7 primaries. According to
>>>>> http://www.oecd-nea.org/janisweb/ , N14 (d,n + alpha) C11 is a
>>>>> possible
>>>>> reaction. However, the cross section is not significantly higher than
>>>>> the
>>>>> well-documented N14 (d,n) O15 reaction which is not happening at all.
>>>>> Additionally there are some N14 (n, something) something reactions
>>>>> possible that do not seem to take place.
>>>>>
>>>>> I expect some basic mistake in my input file that I fail to find
>>>>> myself.
>>>>> I'd be grateful if someone would point me towards the origin of the
>>>>> problem or maybe even present a solution. I'm appending my input and
>>>>> the
>>>>> tab.lis file.
>>>>>
>>>>> Thank you very much.
>>>>> Best regards
>>>>>
>>>>> Marius Arenz
>>>>>
>>>>> __________________________________________________________________________
>>>>>
>>>>> You can manage unsubscription from this mailing list at
>>>>> https://www.fluka.org/fluka.php?id=acc_info
>>>>>
>>>>>
>>>
>>>
>
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Received on Mon Oct 28 2019 - 17:34:58 CET