Low energy neutron xsec not found for Tellurium

Hi Experts!

I want to look for the gamma shielding behavior of 30TeO2-30B2O3-30Bi2O3-10TiO2 glasses and need to obtain relevant quantities (e.g, LAC,MAC,HVL,MFP etc.) with varying thickness of attenuator. As Tellurium isn’t in the list of low energy neutron sxec library of FLUKA Available cross sections — FLUKA Manual, so LOW-MAT card isn’t helpful. Also i downloaded and successfully installed the JEFF 3.3 neutron library into my FLUKA package v4-1.1 and updated my Flair to v3.2-4.5 to be able to use the LOW-PWXS card. I added into my input an empty field LOW-PWXS card but the error rests same. Later on i m also interested in photonuclear reactions, activation and neutrons shielding problem for this material under (0.015-20)MeV gamma energy.

I have red almost all the relevant threads on the forum but i m still unable to resolve my problem. My necessary questions are:

1- Is there any way other than i have tried to overcome the error.
2- LOW-MAT card is required if i used name other than the FLUKA predefined for materials to link it to the low energy neutron xsec library. Is this card still requires if i override other parameters of material (e.g density).
3-Are my material cards looks good and correctly defining the mentioned glass material and threshold parameters for the attenuation under the gamma range.

Kindly guide me.
bdx crystal.inp (3.7 KB)

Dear @zahi,

I managed to run your input without any problems.
I suggest installing the latest version of FLUKA - v 4.3.3.


Thank you for your reply.
It sounds good to me but unfortunately i am not able to download the latest version of FLUKA. Would you like to suggest any other way to resolve my issue on a current versions of Flair and FLUKA that i have mentioned.

Best regards

Can you please share your .out file?

Since the low-energy neutron cross sections are not defined for Tellurium, I think that the only workaround (if you are not able to upgrade the FLUKA version in order to have the PW treatment available) is to find a material with similar cross sections that is on the list.


Yes here is the file i have attached.
bdx crystal001.out (30.9 KB)

Yes you are right i came through this point under the thread before but i don’t know how can i best choose the material which shows similar cross secction as Tellurium. And also i want to know by setting neutron cross section to other material, will it affect the results for photonuclear reactions, activation and neutron shielding parameters/studies for my material?

Kind regards

You can compare the cross section for Te with the ones corresponding to other materials by using this website: ENDF: Evaluated Nuclear Data File

Yes, it will affect the results since the various isotopes production is strongly dependent on the xs.

1 Like

Thank you very much, i got it now.
My last question is, If i override or change the density of the predefined FLUKA materials after importing into input then LOW-MAT card is still required or not?

Yes, you need to add the LOW-MAT card.

Please note that, as already pointed out, using a (very) obsolete version is definitely not a meaningful solution to your problem (it’s actually its reason, as indicated by @Mihaela_Parvu ) and this forum, in the interest of everybody, is intended to provide support for the latest release only, which is the one actually representative of the FLUKA results.
If you are unable to download the latest version, make sure to have a valid registration and use the contact form if needed.