Bug in as1aem1 splitting kernel + minor things - #558
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felixhekhorn
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Thank you for your fixes!
- the typo
orders->order: how did that ever work? 🙈 -
$j_{12}$ : a clear bug as can be seen from other invocations (thankfully that function is never used in practice) -
$N_C$ factor: comparing gg toEq. (31) of :cite:deFlorian:2015ujtI can justify the 4 (coming from the normalization of both$\alpha_s$ and$\alpha_{em}$ ), and I think in the diagram for phg (which is just a quark loop) there is no room for any other color factor apart from$T_R$ (all the other diagrams must then have the same color).
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While debugging EKO evolution against my development version of eMELA, I realised that in the gluon-initiated mixed QED-QCD splitting kernels there is an additional factor of NC, that according to eq.(29)-(31) of 1512.00612 I think should not be there. By removing it, I find closer agreement to my numbers. Then I also fixed a typo in one tutorial notebook and I think that the argument of j12 in n3lo_decompose_expanded should be beta0 and not nf.