I attempt to calculate the Lα and Lβ photon spectrum of X-ray characteristic radiation from lead atoms irradiated with a beam of monoenergetic photons of energy 60keV. In principle, I identified most of the lines characteristic of Pb. Some of the lines are not visible, but this can still be OK. On the other hand, I have a problem because I have a line in the spectrum with an energy of ~12.65keV and I can’t identify it meaningfully. The lead transition table doesn’t show anything with that energy, and it shows everything that has been identified in the area (Table of Isotopes decay data).
I suggest that, you first find all the X-ray lines (found in modern references) with their intensity ratios first. Take into account that it is possible to find some lines as sum peaks, such as:
12.7913 keV= 10.449 + 2.3423,
14.797 keV=12.1432 + 2.6538
and then after you are sure that the calculations are good, and the strongest lines is ok with its intensities. You start examining what belongs to you or not.
This is because I searched alot and I couldn’t fiend any relation to the 12.65 keV
Best Regards
Mohamed Fayez
The following table summarizes the origin of the various lines you’re witnessing, detailing the subshell where the vacancy was left (as well as its binding energy in FLUKA), the subshell from which an electron transitioned to fill the vacancy (as well as its binding energy in FLUKA), the resulting x-ray line energy and its spectroscopic labeling (following table 2 of this reference). I’ve just focused on the two lines immediately at ~12.65 keV:
Vacancy subshell
Binding energy (keV)
Subshell from which e- transitions
Binding energy (keV)
Gamma energy (keV)
Transition
L2
15.251
M4
2.5947
12.6563
L \beta_1
L3
13.04
N5
0.41249
12.62751
L \beta_2
What you’re witnessing are differences at the level of mere 10s of eV (!) in atomic (sub)shell binding energies among various references, which should not be an issue provided lines energies are self-consistently determined from energy level differences.
To have an idea of what’s in the market, see the second paragraph of page 3 of this NIST database manual.
