Reference used to build database of Xray_lines intensity weights?

[Andrea-gm]

I was wondering if somebody knows from which source the intensity weights of elemental xray lines have been taken. They can be found at exspy.material.elements.(ELEMENT SYMBOL HERE).Atomic_properties.Xray_lines

Also, somehow the M lines are missing for elements from Z = 30 (Zn) to Z = 56 (Ba)

[ericpre]

Based on a comment in the code,, they come from https://www.nist.gov/pml/x-ray-form-factor-attenuation-and-scattering-tables.

It would be good to include this comment in the corresponding docstring.

[Andrea-gm]

Thanks for the quick reply!

[Andrea-gm]

I confirm that the M lines are missing up to Z = 56. I suspect this is because the Ma1 lines do not exist for these elements. But the Mz do.