The Tech Basement

So there is a possible bug that I am trying to wrap my head around. In the OBTD log files from KSHELL, the OBTDs are listed in blocks where each block represents an initial and a final state aka. one specific transition. For example

w.f.  J1=  0/2(    3)     J2=  2/2(    1)
 B(L;=>), B(L ;<=)      0.00622     0.00207
 <||L||>      3    1    -0.13590     0.11892

  i  j      OBTD    <i||L||j>  OBTD*<||>
  1  1     0.00244     5.79655     0.01416
  1  2    -0.00012     1.54919    -0.00018
  1  9     0.00000     0.00000     0.00000
  1 10     0.00000     0.00000     0.00000
  ...

This block represents the OBTDs for the transition from the 3rd 0- state to the 1st 1- state (the parity is not listed in the block, but I know it is negative). Now, there is no guarantee that the 3rd 0- state has higher energy than the 1st 1- state. It might be so, but it is not guaranteed. If the initial state however has lower excitation energy than the final state then the OBTD indices in the blocks ($i, j$) have to be swapped in order to make it so that the final state is of lower energy.

So I made a short script which runs through all of the OBTD blocks and looks up the excitation energy of the initial and final state for the given block. The result was that 628337 of 1280000 (49.09 %) blocks had initial state excitation energy lower than the final state. Thats good, as expected, some of the final states are of lower energy and some are of higher. The puzzle however is that when I make a sub-set of transitions, selecting only the transitions which are present within the $E_\gamma = [0, 3]$ MeV region of the $M1$ GSF then only 3 of 230397 (0.00 %) transitions have initial energies lower than final. I don't understand where in the process of calculating the GSF that this kind of energy sorting happens.

So if you take a look at the loader function on lines 159 and 174 here, you can see that transitions with negative gamma energy are skipped in the case where the initial and final state are the same, or flipped in the case where the initial state and final state are different. Therefore there should be no transitions loaded into kshell-utilities where the initial energy is lower than the final. Why a very few transitions, eg. 3, manage to sneak through is not known to me at the time, but the point is that I have already dealt with the situation when the values are loaded from the KSHELL log files.