boundary crossing - energy deposition

Dear Ioannis,

I forward your mail to the discussion list, to which I ask you to send
any further correspondence.
I am retired now, and I am not able to give you the advice you expect.

Best regards,

Alberto

On Tue, 28 Aug 2012, Ioannis Kantemiris wrote:

> Dear Dr. Fasso,
>
> as a continuousness to our previous communication,
> I followed your hints but the results aren't the expected one as you can see in the following table:
>
> without MULSOPT I get the best results
> accuracy: 2.8% (error <2% of the value in all calculations)
>
> MULSOPT 1 scattering -->2.95%
> MULSOPT 2 scattering -->2.85%
> MULSOPT 3 scattering -->3.1%
>
> Am I missing something?
>
> MATERIAL 6. 12.011 1.7 20. 0.GRAPHITE
> MATERIAL 6. 12.011 1.7E-03 21. 0.GRAPH_CAV
> LOW-MAT GRAPHITE 6. -3. 296. 0.0 0.CARBON
> LOW-MAT GRAPH_CAV 6. -3. 296. 0.0 0.CARBON
> EMFFIX 20. .00007 21. .00007
>
> EMFCUT -0.000005 1. 0.0 20. 21. 1.
> MULSOPT 1. 1. 1. 1. 1. 3. GLOBEMF
>
>
> Thank you in advance,
>
> Ioannis
>
>
> On Jul 12, 2012, at 5:12 PM, Alberto Fasso' <fasso_at_slac.stanford.edu> wrote:
>
>> Dear Ioannis,
>>
>> then you should use MULSOPT to force one or more single scattering steps
>> when crossing a boundary.
>>
>> Alberto
>>
>>
>> On Wed, 11 Jul 2012, Ioannis Kantemiris wrote:
>>
>>> Dear Dr. Fasso,
>>>
>>> the simulation of the ionizing chambers is difficult and different from
>>> our initial goal.
>>> Our initial goal is to check the condensed simulation of electrons (e.g.
>>> Sempau et al PMB 51 (2006) 3533?3548).
>>>
>>> Thank you very much for your help and wish you all the best.
>>>
>>> Ioannis
>>>
>>>
>>>
>>>
>>>> Dear Ioannis,
>>>>
>>>> crossing a boundary is a geometry event, not a physics one. The electron
>>>> energy
>>>> when they cross the boundary depends on the electron tracking inside the
>>>> region
>>>> where the electron comes from.
>>>> You can optimize the multiple scattering with MULSOPT (look at the
>>>> Examples 1
>>>> and 2), and you can also optimize the step with EMFFIX.
>>>> But simulating ion chambers is a more difficult task, because you must
>>>> take
>>>> into account the ion recombination.
>>>>
>>>> Alberto
>>>>
>>>> On Mon, 9 Jul 2012, Ioannis Kantemiris wrote:
>>>>
>>>>> Dear Dr. Fasso,
>>>>>
>>>>> My post to FLUKA forum was very misleading and I'm sorry for this.
>>>>> This email is addressed to you and not to the forum because it is part
>>>>> (at
>>>>> least this is our intention) of a small project and we want to publish
>>>>> the
>>>>> data.
>>>>> I would like to calculate FLUKA's accuracy when electrons cross a
>>>>> boundary
>>>>> (and not depositing energy at the boundary). As you know, this is very
>>>>> important for the simulation of ionization chambers.
>>>>>
>>>>> Sincerely yours,
>>>>> Ioannis Kantemiris
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>> Dear Ioannis,
>>>>>>
>>>>>> when electrons traverse a boundary they don't deposit any energy!
>>>>>> They do when they travel INSIDE a region, not when they cross
>>>>>> a boundary.
>>>>>>
>>>>>> Please send again your question in a more clear way. In general, you
>>>>>> need to adjust EMFCUT (both with a SDUM blank and equal to PROD-CUT).
>>>>>> Forget about EMFFIX and MULSOPT.
>>>>>>
>>>>>> Alberto
>>>>>>
>>>>>>> Dear experts,
>>>>>>> I would like to increase the accuracy of the calculated energy
>>>>>> deposition
>>>>>>> when electrons transverse a boundary.
>>>>>>> I'm trying to adjust the EMFCUT, EMFFIX and MULSOPT cards in order to
>>>>>>> achieve this.
>>>>>>> Please inform me if I'm missing something.
>>>>>>> Thank you in advance
>>>>>>> Ioannis
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>> --
>>>> Alberto Fasso`
>>>> SLAC-RP, MS 48, 2575 Sand Hill Road, Menlo Park CA 94025
>>>> Phone: (1 650) 926 4762 Fax: (1 650) 926 3569
>>>> fasso_at_slac.stanford.edu
>>>>
>>>
>>>
>>>
>>
>> --
>> Alberto Fasso`
>> SLAC-RP, MS 48, 2575 Sand Hill Road, Menlo Park CA 94025
>> Phone: (1 650) 926 4762 Fax: (1 650) 926 3569
>> fasso_at_slac.stanford.edu
>
>

-- 
Alberto Fasso`
SLAC-RP, MS 48, 2575 Sand Hill Road, Menlo Park CA 94025
Phone: (1 650) 926 4762   Fax: (1 650) 926 3569
fasso_at_slac.stanford.edu