Thank you Mario and Francesco. I am clear on this now.
I do have another question. Does FLUKA handle magnetic field through
non-vacuum regions?
We have a case here where the vacuum box region of a bending magnet
upstream of the 100 kW beam dump can be filled with stainless steel.
This is to get the back-scattered electrons shower in the s.s. region
with the s.s. providing some attenuation for photons. The energy of the
back-scattered electrons (going through the beam pipe is below 10 MeV.
I don't see any obvious bending happening when I turn the material in
the B field region to s.s. Maybe it is because the B field immediately
steers the electrons into the s.s. region.
Just wanted to make sure the FLUKA allows for having magnetic field
inside a non-vacuum region.
Thanks a lot,
Mina
On 14-02-18 12:43 PM, Santana, Mario wrote:
> No, you always need to set the appropriate flag in ASSIGNMAT, regardless
> whether you use a simple field (MAGNFIELD only) or a programmed one
> (magfld.f) .
>
On 14-02-18 11:50 AM, Francesco Cerutti wrote:
>
> Not at all. A region will be considered as magnetic only if it is
> declared as such in the respective ASSIGNMAT card. And the reason for
> that is what I indicated below as second and more important argument.
>
> Cheers
>
> Francesco
>
> **************************************************
> Francesco Cerutti
> CERN-EN/STI
> CH-1211 Geneva 23
> Switzerland
> tel. ++41 22 7678962
> fax ++41 22 7668854
> On 2/18/14 11:17 AM, "Mina Nozar" <nozarm_at_triumf.ca> wrote:
>
>> Dear Francesco,
>>
>> So do I understand correctly that if one needs to assign/associate a
>> magnetic field to a region of interest in the ASSIGNMAT card, if one
>> uses the MAGNFIELD card for a simple magnetic field setting but NOT if
>> one uses the magfld.f to set and assign the magnetic field to a given
>> region.
>>
>> Thanks and best wishes,
>> Mina
>>
>> On 14-02-14 12:57 PM, Francesco Cerutti wrote:
>>> Dear Mina,
>>>
>>> first of all we just saw with Brandon that, if you are fine with a
>>> constant field, you do not need to write a magfld.f routine but it is
>>> enough to define it in the MGNFIELD card. Then ASSIGNMAT is essential
>>> to tell the code in which regions that field should be applied.
>>>
>>> Furthermore and more important, you definitely do not want to ask the
>>> code to go always through the magnetic tracking algorithm - by far
>>> more complex than a straight step - despite the fact that no magnetic
>>> field is present in your region, and to call the magfld.f routine at
>>> each substep to get back a humiliating zero.
>>>
>>> Ciao
>>>
>>> Francesco
>>>
>>> **************************************************
>>> Francesco Cerutti
>>> CERN-EN/STI
>>> CH-1211 Geneva 23
>>> Switzerland
>>> tel. ++41 22 7678962
>>> fax ++41 22 7668854
>>>
>>> On Fri, 14 Feb 2014, Mina Nozar wrote:
>>>
>>>> Hello Francesco and everyone else.
>>>>
>>>> Just trying to understand the flow/logic of assigning magnetic fields
>>>> in a region.
>>>>
>>>> Here is my understanding and a question where I lack understanding...
>>>>
>>>> 1) MGNFIELD card activates calling the subroutine MAGFLD defined in
>>>> mgfld.f
>>>> 2) In subroutine MAGFLD, one defines the intensity and direction of
>>>> the magnetic field(s) and assigns it to a given region(s).
>>>> 3) Set Field to Magfiled in the ASSINMAT card for the region(s) with
>>>> magnetic field.
>>>>
>>>> What I don't understand is why do we need to turn on magnetic field
>>>> in the ASSIGNMAT card? Is this not already set via MAGFLD?
>>>>
>>>> Best wishes,
>>>> Mina
>>>>
>>>> On 14-02-14 01:57 AM, Francesco Cerutti wrote:
>>>>> Hallo,
>>>>>
>>>>> actually, in case of constant magnetic field in all magnetic
>>>>> regions, the
>>>>> MGNFIELD card is enough (as stated in the manual). It will
>>>>> automatically
>>>>> feed the default magfld routine (the one provided in usermvax,
>>>>> where in
>>>>> fact the comment
>>>>> * 2 Tesla uniform field along +z:
>>>>> does not apply) and you do NOT need to link the latter into a
>>>>> customized
>>>>> executable, unless you want to modify it, since it is already in the
>>>>> standard FLUKA library and linked in the standard executable.
>>>>>
>>>>> Cheers
>>>>>
>>>>> Francesco
>>>>>
>>>>> **************************************************
>>>>> Francesco Cerutti
>>>>> CERN-EN/STI
>>>>> CH-1211 Geneva 23
>>>>> Switzerland
>>>>> tel. ++41 22 7678962
>>>>> fax ++41 22 7668854
>>>>>
>>>>> On Thu, 13 Feb 2014, Dr. Vittorio Boccone wrote:
>>>>>
>>>>>> No you should still include and link the default magfld routine
>>>>> which is
>>>>>> configured for a uniform magnetic field, as explained in the
>>>>> lecture and > the
>>>>>> tutorial.
>>>>>> Best
>>>>>> V.
>>>>>> Sent from my iPad
>>>>>>> On 13/feb/2014, at 22:42, "REDDELL, BRANDON D. (JSC-EV511)"
>>>>>> <brandon.d.reddell_at_nasa.gov> wrote:
>>>>>>> Thanks Vittorio.
>>>>>>> So in my simple problem, I am not using the magfld.f
>>>>> routine,
>>>>>> just only the MGNFIELD card. So, could you confirm if these
>>>>>> cards should work:
>>>>>>> MGNFIELD 20.0 0.2 0.10 0.0
>>>>>> 0.0 1.0
>>>>>> STEPSIZE 0.5 0.0 VAC2 0.0
>>>>>> 0.0 0.0
>>>>>> EMF
>>>>>> EMF-OFF
>>>>>> .
>>>>>> .
>>>>>> .
>>>>>> ASSIGNMA VACUUM VAC2 1.0
>>>>>> (the 1 here is at WHAT(5)
>>>>>>> Thanks.
>>>>>>> Brandon
>>>>> _______________________________________________________________________
>>>>> _____
>>>>>>> From: Vittorio Boccone [dr.vittorio.boccone_at_ieee.org]
>>>>>> Sent: Thursday, February 13, 2014 2:47 PM
>>>>>> To: REDDELL, BRANDON D. (JSC-EV511); fluka-discuss_at_fluka.org
>>>>>> Subject: Re: [fluka-discuss]: magnetic field in vacuum
>>>>>>> Sure, check out the magnetic field exercise (solution) on the
>>>>> advanced
>>>>>> course:
>>>>>>
>>>>> http://www.fluka.org/fluka.php?id=course&sub=program&navig=2&which=triu
>>>>> mf20
>>>>>>> 12
>>>>>> Best
>>>>>> V.
>>>>>>> On 2/13/2014 8:47 PM, REDDELL, BRANDON D. (JSC-EV511) wrote:
>>>>>>> FLUKA Users/Experts,
>>>>>>>>> Do the magnetic field settings in a region (using
>>>>> MGNFIELD
>>>>>> card along with WHAT card 5 in ASSIGNMA Card) work if the
>>>>>> region of the B field is a vacuum?
>>>>>>>>> Brandon
>>>>>>>>>
>>>>
>
Received on Mon Feb 24 2014 - 22:32:53 CET