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Forum: Hadronic Processes
Re: Question protons from neutrons (Andrea Di Simone)
Re: None Re: protons from neutrons (Dennis H. Wright)
Date: 24 Feb, 2010
From: Andrea Di Simone <Andrea Di Simone>

Hello Dennis,

and thanks for your quick answer.

I made some investigation, and the processes involved in limiting the step appear to be hElastic and Transportation. As far as the material is concerned, I see these clone particles in several materials (quartz, plastic scintillator, CsI).

I have prepared two verbose outputs of two tracks showing this sort of behavior. The first one is in

You'll have to go up to event 6 to see the output from verbose tracking (level 5) of one of the neutron tracks.

Interesting steps are, for example, 95 and 96, where two identical protons are created. I also found one more strange effect. Step 99 is creating the same proton as steps 95 and 96, plus a second one, with different momentum. In steps 100 and 238 the same proton pair is created again.

To quickly find interesting steps, even in the events/tracks with no verbose tracking, look for "*** ", which will show you all secondaries from neutrons. The line contains the index of the secondary, the material name, the neutron track id, the process name (from GetProcessDefinedStep), the secondary pdg id, the 3 components of the momentum, process and subprocess id.

One more verbose tracking from an interesting neutron is in the file

where at steps 9,10,13,14 you can see the same secondary being created, except that now it is a Fe56, not a proton. If you look at the second event in this file (with no verbose tracking unfortunately) you'll notice the same proton being created in three different materials.

I still hope this is not a bug, but I really don't have any clue about what could be producing these secondaries, so any help is much appreciated.

Thanks for your help,


PS: material names (quartz, emcCsI, *scin*) should be self explicative. If you need information about a particular material just let me know.


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1 None: Re: protons from neutrons   (Andrea Di Simone - 03 Mar, 2010)
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