6j-Symbol is not triangular in LevelPlot.drawSpectra() about arc-alkali-rydberg-calculator

[nikolasibalic]

Let me check this one, this looks like some bug.

[nikolasibalic]

@zzpwahaha thanks for this,

It's not bug - just the call to get level diagram should be:

atom = Rubidium87()
level = LevelPlot(atom)
level.makeLevels(5,6,0,3)
level.drawLevels()
level.showPlot()

Note that you should call drawLevels instead of drawSpectra (that function is not officially supported at the moment - it remains from some past developments). In general program stops if Wigner6J is not triangular because that usually means some entered parameters are not correct. But in this case this is probably because drawSpectra is old and should not be called (it's not actually visible in documentation).

Also note that grund state of rubidium corresponds to n=5, so there is probably no reason to try to plot from n=4 (first argument of makeLevels).

[zzpwahaha]

Thanks for the reply. I see.
Btw, the reason I start from 4 is to include to 4D state as it is energetically higher than 5S_{1/2}
And I thinks that is supported in plotLevels?

[nikolasibalic]

Ah yes, you are right. It is supported. I forgot for the moment these, but luckily ARC didn't. :)
Yes, starting with 4 you will get correct requested plot with 4D states included.

[zzpwahaha]

Thanks :)