MONACO missing Carbon nuclide information in libraries

[Zeyu Chen]

Dear SCALE users,

         I was running some simple bench marking examples in MONACO. (SCALE version 6.2)

         the case is quite simple: 

         look at the neutron spectrum from a point(small sphere) source penetrating a sphere surrounding it. The sphere is filled with CO2 gas in this case.

         Previously I have tested this with void space and water, and they both worked very well.

         However, when I changed the material to CO2, the program gives an error saying: " Could not find nuclide 6012 with mixid 2 on working library on 4"

         the error exists for 6013 as well, and any composition that contains carbon. I have also tested pure Carbon and UC and they both showed the same error. However, Graphite was working because it uses the id: 3006000.

         I have also tried to use different MG libraries such as V7-252 and tried both ENDF/B-VII.0 and ENDF/B-VII.1 version, neither of them worked.

         

         

         I suspect this issue is with "ampxfileunit=4" but Chapter 10 in the manual didn't really tells how to choose a correct file unit for AMPX libraries.

         I would be very glad if somebody can help me on this.

Thanks you!

Zeyu Chen

[Cihangir]

Dear Zeyu,

There are no isotopic evaluations of carbon in ENDF/B-VII (VII.0 nor VII.1), and only elemental carbon (6000) exists. Although the StdComp (used by Fulcrum and other SCALE modules) lists 6012 and 6013 by decomposing element 600 into its isotopes, modules only work with the available cross section data which only has elemental (6000) one. Please remove 6012 and 6013 entries in your "crossSections" block of MONACO and add 6000 with total number densities of 6012 and 6013.

Cheers,

Cihangir

[Zeyu Chen]

That worked, thank you! 

Best,

Zeyu Chen