energy absorption coefficients

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energy absorption coefficients

I am working in the field of Radiotherapy using G4.
  I have a technical problem in accessing information in G4
  that I don't know how to resolve it. 
  The question concerns the fact of how to access the photon 
  interaction coefficients in G4. 
  In our study we use variance reduction techniques to estimate kerma 
  in water. For this study we need the energy absorption coefficients 
  mu_en.
  Do you know how can we obtain this data in G4?

  Thanks in advance.
  --

Re: energy absorption coefficients by michel maire <michel maire>, 18 Nov, 2002 Re: energy absorption coefficients (Domingo Granero) User Domingo Granero wrote: >> I am working in the field of Radiotherapy using G4. >> I have a technical problem in accessing information in G4 >> that I don't know how to resolve it. >> The question concerns the fact of how to access the photon >> interaction coefficients in G4. >> In our study we use variance reduction techniques to estimate kerma >> in water. For this study we need the energy absorption coefficients >> mu_en. >> Do you know how can we obtain this data in G4? >> >> Thanks in advance. >> -- >> Each process (GammaConversion, Compton, PhotoEffect, Rayleigh) is treated independently. For each of them the input is cross section per atom and mean free path. Never G4 use the concept of total cross section nor interaction or absoption coefficients. Therefore to compute them, adds the individual cross sections or perfoms a simulation and extract it from a fit.

Re: energy absorption coefficients by Vladimir Ivanchenko <Vladimir Ivanchenko>, 18 Nov, 2002
Re: energy absorption coefficients (Domingo Granero)

On Mon, 18 Nov 2002, Domingo Granero wrote: > *** Discussion title: Electromagnetic Processes > Email replies to PublicHyperNews@slac.stanford.edu must include: > In-Reply-To: <"/emprocess/63"@geant4-hn.slac.stanford.edu> > Subject: ...change this to be about your reply. > > I am working in the field of Radiotherapy using G4. > I have a technical problem in accessing information in G4 > that I don't know how to resolve it. > The question concerns the fact of how to access the photon > interaction coefficients in G4. > In our study we use variance reduction techniques to estimate kerma > in water. For this study we need the energy absorption coefficients > mu_en. > Do you know how can we obtain this data in G4? > > Thanks in advance. > -- Hello, There is a problem - may be other users can help you. The problem is that in G4 we are working with cross sections. One can access G4 cross section for given particle and material. If you know a good way how to obtain absorbsion coefficients from the cross sections - you problem is solved. VI

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