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Forum: Hadronic Processes
Re: Question unrealistic result with Hadr02 (Robert Nnaemeka)
Re: Idea Re: unrealistic result with Hadr02 (Vladimir Ivanchenko)
Date: 07 Mar, 2015
From: Robert Nnaemeka <Robert Nnaemeka>

Thanks Vladmir. I used the approximate mean ionization potential of element given by 10*Z eV, where Z is atomic number of the element to set the lowest energy. For Al target, just like other metals, I couldn't get count for electrons until around proton energy of ~ 80keV upward. Even at that, the number of electrons per incident protons is much higher than the experimental data. A little research revealed that the physics process occurring at that energy is impact ionization and hence need G4ImpactIonization. Is this implemented in all the modular physics list present in the Hadron examples or do I have to add it? Also, I observed that deuteron needs a higher energy to produce electron secondaries on being fired into metalic targets, even though the lowEdge and cut value are such that the electron threshold cut in energy is 2 eV? Our experiment using 100 - 120 KeV deuteron is giving copious electrons at these energies.

On Tue, 03 Mar 2015 10:31:46 GMT, Vladimir Ivanchenko wrote:

> Hello,
> 
> Unfortunately, default EM models for ionization have an internal
> limitation: production threshold for delta-electrons cannot be below
> mean ionization potential. This limit is needed because models for
> differential cross section become not applicable.
> 
> We have models which may work with zero threshold but for today they are
> applicable to liquid water (DNA) and for Silicon (MicroElec) only.
> 
> So, there is no model for Molybdenum for production of very low-energy
> e-.
> 
> VI
> 

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1 Idea: Re: unrealistic result with Hadr02   (Vladimir Ivanchenko - 10 Mar, 2015)
2 Idea: Re: unrealistic result with Hadr02   (Vladimir Ivanchenko - 10 Mar, 2015)
1 Feedback: Re: unrealistic result with Hadr02   (Robert Nnaemeka - 10 Mar, 2015)
2 None: Re: unrealistic result with Hadr02   (Robert Nnaemeka - 10 Mar, 2015)
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