Call anomalous mass dimension \gamma_m

[felixhekhorn]

To avoid confusion, let's call he anomalous mass dimension \gamma_m (in contrast to the anomalous PDF dimension that we keep at \gamma). This has to be changed:

• in the docs
• in the paper
• in the code (if used anywhere ... I think, gamma function and anomalous dimension are fine as names ...)

[giacomomagni]

Okay I agree. Will take care of fixing this.

[giacomomagni]

I noticed that we do have all the ingredients for easily adding also the N3LO msbar evolution. Shall I open a PR?

[felixhekhorn]

I guess later we want to go full N3LO - so I'd say go ahead ...