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science:phd-notes:2025-02-13-obtd [2025/02/13 04:23] – created jon-dokuwikiscience:phd-notes:2025-02-13-obtd [2025/02/17 02:05] (current) – jon-dokuwiki
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-===== Possible bug in the OBTD calculations =====+===== [SOLVED] Possible bug in the OBTD calculations =====
  
 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 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
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 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 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.
  
-I think I have an idea...! TBC+==== Solution ==== 
 +So if you take a look at the loader function [[https://github.com/GaffaSnobb/kshell-utilities/blob/e08cba491ccdfbbef8beb845e91aace59b656ebc/kshell_utilities/loaders.py#L159|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.
science/phd-notes/2025-02-13-obtd.1739417015.txt.gz · Last modified: 2025/02/13 04:23 by jon-dokuwiki