Missing cross section data sets from TENDL and NDL (with AllHP physics)

Hi,

I am having trouble with the G4TENDL1.3.2 (and G4NDL4.6) database. I am trying to simulate where neutron induced activity ends up in the surrounding walls near the target chamber. The main reaction used is the p+18O-> 18F+n reaction at 18 MeV. I am using the QGSP_BIC_AllHP physics package with Geant4.10.6. However the cross section data for the nuclei 18O,17O and 16O seem to be missing from the TENDL dataset.

So if I am using the STCyclotron example from advanced examples with the target modified to 98.3% of 18O, 0.7 of 17O and 1% of 16O with the G4PROTONHPDATA pointing to /TENDL1.3.2/Proton and the G4NEUTRONHPDATA pointing to /G4NDL4.5. the program will run and use the wrong cross sections. When initiating the run the following shows up:

NeutronHP: 4TENDL1.3.2/Proton/Inelastic file for Z = 8, A = 10 is not found and NeutronHP will use /home/aton3/joaslott/Geant4/source/geant4.10.06-install/share/Geant4-10.6.0/data/G4TENDL1.3.2/Proton/Inelastic/CrossSection/8_16_Oxygen

NeutronHP: 4TENDL1.3.2/Proton/Inelastic file for Z = 8, A = 9 is not found and NeutronHP will use /home/aton3/joaslott/Geant4/source/geant4.10.06-install/share/Geant4-10.6.0/data/G4TENDL1.3.2/Proton/Inelastic/CrossSection/8_16_Oxygen

NeutronHP: 4TENDL1.3.2/Proton/Inelastic file for Z = 8, A = 8 is not found and NeutronHP will use /home/aton3/joaslott/Geant4/source/geant4.10.06-install/share/Geant4-10.6.0/data/G4TENDL1.3.2/Proton/Inelastic/CrossSection/8_16_Oxygen

@@@ G4ParticleHPInelastic instantiated for particle proton data directory variable is G4PROTONHPDATA pointing to /home/aton3/joaslott/Geant4/source/geant4.10.06-install/share/Geant4-10.6.0/data/G4TENDL1.3.2/Proton/Inelastic

NeutronHP: /Capture file for Z = 8, A = 10 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Capture/CrossSection/8_16_Oxygen

NeutronHP: /Elastic file for Z = 8, A = 10 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Elastic/CrossSection/8_16_Oxygen

NeutronHP: /Inelastic file for Z = 8, A = 10 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Inelastic/CrossSection/8_16_Oxygen

NeutronHP: /Capture file for Z = 8, A = 9 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Capture/CrossSection/8_16_Oxygen

NeutronHP: /Elastic file for Z = 8, A = 9 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Elastic/CrossSection/8_16_Oxygen

NeutronHP: /Inelastic file for Z = 8, A = 9 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Inelastic/CrossSection/8_16_Oxygen

NeutronHP: /Capture file for Z = 8, A = 8 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Capture/CrossSection/8_16_Oxygen

NeutronHP: /Elastic file for Z = 8, A = 8 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Elastic/CrossSection/8_16_Oxygen

NeutronHP: /Inelastic file for Z = 8, A = 8 is not found and NeutronHP will use /home/aton3/joaslott/GEANT4/geant4.10.06-install/share/Geant4-10.6.0/data/G4NDL4.6/Inelastic/CrossSection/8_16_Oxygen

Litterature suggests that the TENDL database seems to be the right way to go with the 18O(p,n)18F reaction at 17-18 MeV. At least for older versions. I am therefore hesitant to change to other data sets.

Any advice on how to proceed?

Thank you for your time.

Oh! I have the same question with you.

8_18_Oxygen does not exist in the G4TENDL database and therefore Geant4 gets the closer isotope, or it sets the O18 cross section to 0 if you have set the environmental variable
export G4NEUTRONHP_SKIP_MISSING_ISOTOPES=1

But 8_17_Oxygen is included, and indeed I cannot reproduce your problem for this isotope.

For 8_18_Oxygen I can give you a cross section based on TENDL 2009 (G4TENDL132 uses TENDL 2014) which has the O18(p,n)F18 cross section corrected to match the experimental data found in the IAEA medical physics database, which you can use at your discretion.

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Hello,

If you copy the database locally you may replace or add any file. If this will work for you you may propose to update Geant4 database.

VI

We would be very interested in this data, too.

I am attaching the 8_18_Oxygen cross section following the IAEA medical cross section database: 18O9p,n)18F

Just delete the .XS.txt, .F02.txt
8_18_Oxygen.F02.txt (1.1 MB)
suffixes and place them in the corresponding directories.
8_18_Oxygen.XS.txt (1.9 KB)

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Hi, joaslott, I also got a question when employ the STCyclotron example.
I calculate Ni64(p,n)Cu64 reaction cross section with G4Tendl1.3.2, but the result seems wrong.
When proton energy is 10 MeV, cross section is about 440 mb, while the data form IAEA and talys websit is 814 mb and 772 mb.
I can’t find the reason, hope get you help, thanks!

Hi, I am interested in the simulations of this proton reaction, so I would really like to thank you for sharing these files with us. For future development, I would like to ask you, how are you transfering ordinary ENDF files into files that are readable by Geant4 and how do you know in which directory you have to upload them? I was trying to find out it by myself but I found a little bit difficult and confusing. Thank you for your answer.
Marek

Changing the ENDF format to the G4 one is a non-trivial thing, and there is only one guy who has the code to do it: Emilio Mendoza. So, with any new file you will have to ask him.

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Good job!And, i have some questions about it.What’s the meaning of each row and column of the txt file?How can i write the cross section file?

You just have to delete the files $G4PROTONHPDATA/Inelastic/CrossSection/8_18_Oxygen.z $G4PROTONHPDATA/F02/CrossSection/8_18_Oxygen.z, und put the files in those directories (named only 8_18_Oxygen)

Thank You! And, i also want to learn the meaning of the file. Could you give me some help?