Re: [fluka-discuss]: user biasing using usimbs.f *** Doeimb: importance splitting not performed for missing room, in Emf stack ***

From: Vittorio Boccone <dr.vittorio.boccone_at_ieee.org>
Date: Sat, 25 Apr 2015 11:35:49 +0200

Hi Mina,

sorry for the previous mail. I see that the meaning of my previous message
was heavily affected by the automatic corrector.

It would be nice to see your custom routing as well as the input.

All your region have *importance* 2 and *RR ratio* 2.
If all the regions have the same importance nothing will change.
Vittorio
On Apr 24, 2015 4:20 AM, "Mina Nozar" <nozarm_at_triumf.ca> wrote:

>
> Hi Vittorio,
>
> I am sorry, I don't understand your message.
>
> Do you mean you think I might be doing splitting and RR at the same
time? How could this be?
>
> From the advanced course slides, I see:
> "The Russian Roulette / Splitting will take place at the middle (defined
by the ENTRY) of the step. "
>
> The same routine seems to be working for the proton beam on the target.
So it is an issue with the electron beam. But I don't know how to go about
investigating this. Can one of the experts/developers help please? I am
stuck.
>
> Thank you,
> Mina
>
>
> On 15-04-23 01:45 PM, Vittorio Boccone wrote:
>>
>> HI Mina,
>> I see you might Importance biasing and RR.
>> Beware that the Russian Roulette massacre happens in the middle (defined
by the ENTRY) of the steps, and not o
>> It would be nice to see your custom usimbs.f
>>
>> Best,
>> Vittorio
>>
>> On Thu, Apr 23, 2015 at 2:37 AM, Mina Nozar <nozarm_at_triumf.ca> wrote:
>>>
>>> Thanks Mario.
>>>
>>> But I don't think I have been too aggressive in the biasing.
>>>
>>> I start biasing 1 meter from the center of the target (RMIN = 100 cm)
and bias by a factor of 2 every 35 cm (RINC) until R = 800 cm (RMAX). See
attached image. This is what I print in the output file (for lfirst).
>>>
>>> ***** usimbs CALLED *****
>>> AETE_Cx -1278.
>>> AETE_Cy 8183.88
>>> AETE_Cz 5948.
>>> DMIN_IMP 0.0001
>>> RMIN 100.
>>> RMAX 800.
>>> RINC 35.
>>> 1 99999 99999
0.0000000E+00 1.0000000E+30 0
>>> NEXT SEEDS: E9 0 0 0 0 0 C6AD
2A4C 0 0
>>> 2000 98000 98000
5.6441402E-04 1.0000000E+30 133
>>> NEXT SEEDS: 2C8E4A 0 0 0 0 0 C6AD
2A4C 0 0
>>> 4000 96000 96000
5.5066633E-04 1.0000000E+30 255
>>> NEXT SEEDS: 57629D 0 0 0 0 0 C6AD
2A4C 0 0
>>> ...
>>> ...
>>>
>>> In the .err file, I see:
>>>
>>>
>>> NEXT SEEDS: 0 0 0 0 0 0 C6AD
2A4C 0 0
>>> 1 99999 99999
0.0000000E+00 1.0000000E+30 0
>>> NEXT SEEDS: E9 0 0 0 0 0 C6AD
2A4C 0 0
>>> 2000 98000 98000
5.7591248E-04 1.0000000E+30 133
>>> NEXT SEEDS: 2C8E4A 0 0 0 0 0 C6AD
2A4C 0 0
>>> 4000 96000 96000
5.6066513E-04 1.0000000E+30 255
>>> NEXT SEEDS: 57629D 0 0 0 0 0 C6AD
2A4C 0 0
>>> 6000 94000 94000
5.9057713E-04 1.0000000E+30 409
>>> NEXT SEEDS: 8987D8 0 0 0 0 0 C6AD
2A4C 0 0
>>> 8000 92000 92000
5.9815907E-04 1.0000000E+30 530
>>> NEXT SEEDS: B9BD7F 0 0 0 0 0 C6AD
2A4C 0 0
>>> 10000 90000 90000
6.0090866E-04 1.0000000E+30 666
>>> NEXT SEEDS: E9782F 0 0 0 0 0 C6AD
2A4C 0 0
>>> 12000 88000 88000
6.2340530E-04 1.0000000E+30 808
>>> NEXT SEEDS: 120B7BB 0 0 0 0 0 C6AD
2A4C 0 0
>>> 14000 86000 86000
6.2054852E-04 1.0000000E+30 939
>>> NEXT SEEDS: 14F66E4 0 0 0 0 0 C6AD
2A4C 0 0
>>> 16000 84000 84000
6.1765611E-04 1.0000000E+30 1058
>>> NEXT SEEDS: 17DC3F2 0 0 0 0 0 C6AD
2A4C 0 0
>>> *** Doeimb: importance splitting not performed for missing room
>>> in Emf stack ***
>>> *** Doeimb: importance splitting not performed for missing room
>>> in Emf stack ***
>>> *** Doeimb: importance splitting not performed for missing room
>>> in Emf stack ***
>>> *** Doeimb: importance splitting not performed for missing room
>>> in Emf stack ***
>>> *** Doeimb: importance splitting not performed for missing room
>>> in Emf stack ***
>>> *** Doeimb: importance splitting not performed for missing room
>>> in Emf stack ***
>>> *** Doeimb: importance splitting not performed for missing room
>>> ...
>>> ...
>>>
>>>
>>> Thanks,
>>> Mina
>>>
>>>
>>>
>>> On 15-04-22 02:31 PM, Santana, Mario wrote:
>>>>
>>>> From the message, and given that you were setting importances via
usimbs.f, it seems that you have gone too aggressive in the biasing and you
have filled the emf stack.
>>>>
>>>> This means that you set a step biasing split that was much bigger than
the attenuation for your electrons and photons through your shielding. As a
result, the population of electrons and photons was growing larger every
step, and you filled the memory.
>>>>
>>>> Reduce the parameter by which you bias. Normally you would want to set
that parameter so that the population of your particles of interest stays
more or less constant.
>>>>
>>>> - Mario
>>>>
>>>> From: Mina Nozar <nozarm_at_triumf.ca>
>>>> Date: Wednesday, April 22, 2015 12:36 PM
>>>> To: fluka-discuss <fluka-discuss_at_fluka.org>
>>>> Subject: [fluka-discuss]: user biasing using usimbs.f *** Doeimb:
importance splitting not performed for missing room, in Emf stack ***
>>>>
>>>> Hello everyone,
>>>>
>>>> I have been trying to do biasing via usimbs.f. It has taken me few
days of trial and error. I think I have fixed few issues (one of which
resulted in a core dump).
>>>>
>>>> Now, I am seeing the following message repeated ad nauseam in the
.err file. What does this message mean and how can I go about fixing it?
>>>>
>>>>
>>>> *** Doeimb: importance splitting not performed for missing room
>>>> in Emf stack ***
>>>>
>>>>
>>>>
>>>> Thanks in advance,
>>>> Mina
>>>
>>>
>>
>


__________________________________________________________________________
You can manage unsubscription from this mailing list at https://www.fluka.org/fluka.php?id=acc_info
Received on Sat Apr 25 2015 - 13:05:28 CEST

This archive was generated by hypermail 2.3.0 : Sat Apr 25 2015 - 13:05:41 CEST