# 67Ga and 68Ga cross sections for Li7 beam on Cu target

Dear experts, I hope all is well. I try to reproduce the results from Production cross section of 67Ga and 68Ga from interaction of Li7 beam on Cu target but I ran into the following problems:

1. When I ran the program with the geometry Settings of the input file posted by Riya, all the results were zero. However, upon increasing the thickness of the target, the output displayed results. Could you please tell me why?
2. In the output file, my sigma value is 1922.22522 mb, whereas Riya’s value is 1821.6062mb. This difference could be due to variations in our materials or other factors. Also, I would like to know if the natural copper material is set up as it is in my input file.
3. Based on the method suggested by Riya to calculate the cross-section, the number of stars generated per beam particle is 3.8248E-03 and the total response I received was 9.1815571E-04. However, when I divided 9.1815571E-04 by 3.8248E-03, I got 0.24mb, which is 3 orders of magnitude different from the expected value of 200 mb. Therefore, I am certain that my calculation is incorrect, but I am unsure where the mistake lies. I would greatly appreciate it if you could identify where I went wrong.

Li_Cu.inp (2.7 KB)
Best regards,
Yue Yu

You sent a 7Li beam of 295 MeV per particle (i.e. 42 MeV/n or, more precisely, 42 MeV/nmu, being nmu the nuclear mass unit, i.e. 1/12 of the 12C nucleus mass), while there we were considering a 7Li beam energy of 42 MeV. Read the manual.

Thanks for the clarifying answer! @ceruttif
I have found the source of the solution in the manual and now my simulation results are comparable to those in # Production cross section of 67Ga and 68Ga from interaction of Li7 beam on Cu target

Now, I am interested in the cross-section of the reaction 100Mo(p,2n)99mTc. However, in the AUXSCORE card, I wonder how 99mTc is filtered, and what parameter should represent this “m”?

Regards,
Yue Yu

Unfortunately, no metastable from ground level distinction is presently available at production level. Nevertheless, this is planned to come in the future.

I understand, so I’ll switch to a different tool to study the reaction 100Mo(p,2n)99mTc. Thanks again for your help.