RE: [fluka-discuss]: Turning off biasing with RADDECAY

From: Paul Miyagawa <Paul.Miyagawa_at_cern.ch>
Date: Thu, 17 Oct 2013 14:28:36 +0000

Hello Paola,

I am very much interested in delayed radiation. What I am trying to do is compare results from running two-step and one-step methods in FLUKA. At the moment I am getting discrepancies in these results, so I am trying to trace the source of these. In the two-step I believe the biasing is off, so I am trying to run one-step also with biasing off. (I tried to turn on biasing in two-step prompt radiation step using RADDECAY, but that caused FLUKA to crash.)

Cheers,
Paul

-----Original Message-----
From: Paola Sala [mailto:paola.sala_at_mi.infn.it]
Sent: 17 October 2013 15:16
To: Paul Miyagawa
Cc: Alberto Fasso; Paola Sala; fluka-discuss_at_fluka.org
Subject: RE: [fluka-discuss]: Turning off biasing with RADDECAY

Hello
sorry, but I start being puzzled a bit. What I do not understand is whether you are interested or not in delayed radiation. By delayed radiation I mean decay products of radioactive isotopes that are generated during the beam propagation in matter.
If the answer is not, which is the case for most simulations, then you should forget about the RADDECAY card. The transport thresholds for prompt
("normal") radiation have to be set through the EMFCUT card.
If the answer is yes, then you must use the RADDECAY card, to enable the simulation of radiaoctive decays. The transport thresholds will still have to be set with the EMFCUT card as well, and, only in this case, you can set different thresholds for prompt particles and for particles coming from radioactive decays.
 Hope this helps
Paola

> Hi Paola and Alberto,
>
> Thank you for your explanations. I'm using DEFAULTS PRECISIO, but I
> assume that any biasing introduced by that will be negated by the
> GLOBAL card you suggested.
>
> If I don't use RADDECAY, is there another way I can get the e/m
> transport cutoff behaviour of RADDECAY WHAT(5)? I'm assuming that EMF
> EMF-OFF and EMFCUT apply to both prompt and decay radiation.
>
> Thanks again,
> Paul
>
> -----Original Message-----
> From: Alberto Fasso
> Sent: 17 October 2013 13:35
> To: Paul Miyagawa
> Cc: Paola Sala; fluka-discuss_at_fluka.org
> Subject: RE: [fluka-discuss]: Turning off biasing with RADDECAY
>
> Hi Paul,
>
> don't do it with RADDECAY: the easiest way is to comment all the
> biasing commands you have in input (LAM-BIAS, BIASING, WW-FACTOr,
> EMF-BIAS, LOW-DOWN, LOW-BIAS), and to add at the beginning of input a
> GLOBAL command card with WHAT(2) = -1 (declaration that this run must be fully analogue).
>
> Alberto
>
> On Thu, 17 Oct 2013, Paul Miyagawa wrote:
>
>>
>> Hello Paola,
>>
>>  
>>
>> Thank you for your suggestion. Unfortunately it seems I didn¢t make
>> myself clear. I want biasing OFF for prompt radiation and OFF for
>> decay radiation as well (i.e., I do NOT want biasing on at all).
>>
>>  
>>
>> Cheers,
>>
>> Paul
>>
>>  
>>
>> From: Paola Sala
>> Sent: 17 October 2013 12:38
>> To: Paul Miyagawa
>> Cc: fluka-discuss_at_fluka.org
>> Subject: Re: [fluka-discuss]: Turning off biasing with RADDECAY
>>
>>  
>>
>> Hello
>> The value 0 is ignored. To set bias for decay radiation only the flag
>> should be set to 2  (sse manual :
>>
>> 2.0 = applied to decay radiation only)
>>
>> cheers
>> Paola
>> On 10/17/2013 12:12 PM, Paul Miyagawa wrote:
>>
>> Hello,
>>
>> I am trying to turn off biasing for both prompt and decay
>> radiation using WHAT(4) of the RADDECAY card. I am finding that
>> any flags I set to 0 are treated as 1 (i.e., biasing is turned
>> on for prompt radiation for those particles). Is this expected,
>> and if so then does that mean it is impossible to turn off
>> biasing for both prompt and decay radiation? Thanks for any
>> help.
>>
>> Cheers,
>> Paul
>>
>>  
>>
>>
>>
>
> --
> Alberto Fass
>
>


Paola Sala
INFN Milano
tel. Milano +39-0250317374
tel. CERN +41-227679148
Received on Thu Oct 17 2013 - 17:13:57 CEST