It is the physical age of the particle, not anything related to when (CPU time) FLUKA generates that particle.
If you set AGESTK(NPFLKA) = FLRNDM() * 10e-6 (beware of '*' instead of '/' that you used) the initial age of your particles will be uniformly distributed between 0 and 1E-6 s.
From: Zhiyi Liu <zhiyil_at_triumf.ca<mailto:zhiyil_at_triumf.ca>>
Organization: AAPS_at_TRIUMF
Date: Friday, July 25, 2014 5:32 PM
To: Mario Santana <msantana_at_slac.stanford.edu<mailto:msantana_at_slac.stanford.edu>>, fluka-discuss <fluka-discuss_at_fluka.org<mailto:fluka-discuss_at_fluka.org>>
Subject: Re: [fluka-discuss]: pulsed neutron source
Hi Mario,
I am not sure I fully understand the variable, AGESTK (NPFLKA). It is said that it is the age of primary particles. What does that exactly mean? It means the start time for a particle to be generated? or life time to be allowed? What I need in my issue is to generate neutrons in 10e-6 seconds (a neutron burst). If I set AGESTK(NPFLKA) = FLRNDM()/10e-6, due to my understanding, it means neutrons will be generated in 10-6 seconds?
Thanks.
On 14-07-18 05:25 PM, Santana, Mario wrote:
Hi Zhiyi,
Most likely, the beam on/off function that you remember is that which can be set with the IRRPROFI card, but this is for activation/decay studies and would not work for the purpose you describe.
What Francesco wrote in the thread that you refer at is perfectly valid for your studies. You will need to sample and assign a non-zero start time for the age of your neutrons through the AGESTK (NPFLKA) variable (NPFLKA is the pointer) in the source.f routine. You can then consult that value (the particle age) in user-routines like mgdraw.f and use it do define your time/space spectra.
Mario
From: Zhiyi Liu <zhiyil_at_triumf.ca<mailto:zhiyil_at_triumf.ca>>
Organization: AAPS_at_TRIUMF
Date: Friday, July 18, 2014 10:47 AM
To: fluka-discuss <fluka-discuss_at_fluka.org<mailto:fluka-discuss_at_fluka.org>>
Subject: [fluka-discuss]: pulsed neutron source
Hi,
My question is very similar to the one in the thread:
http://www.fluka.org/web_archive/earchive/new-fluka-discuss/4416.html
We want to set up a pulsed neutron source with a certain pulse width, say 100 us, then we are interested in all neutron transportation afterwards. The pulse width is important for neutron space distributions and time spectra and cannot be handled by normalization. So I am curious if a user can set beam on and off with specific time? I vaguely remember FLUKA has such a function. Please confirm and if not, any solution?
Thanks,
Zhiyi.
--
Zhiyi Liu AAPS_at_TRIUMF
4004 Wesbrook Mall
Vancouver, BC, Canada V6T 2A3
Tel: (604)222-7705
Email: zhiyil_at_triumf.ca<mailto:zhiyil_at_triumf.ca>
--
Zhiyi Liu AAPS_at_TRIUMF
4004 Wesbrook Mall
Vancouver, BC, Canada V6T 2A3
Tel: (604)222-7705
Email: zhiyil_at_triumf.ca<mailto:zhiyil_at_triumf.ca>
Received on Sat Jul 26 2014 - 04:08:20 CEST