MadGraph5_aMC@NLO

QED coupling

Asked by Hannes Jung on 2020-12-03

Dear aMCatNLO experts

for processes where a DY pair is produced, the QED coupling plays a big role.
I was wondering whether and how one can switch from a fixed to a running QED coupling (and vice versa).
Is running alpha_em default in madgraph_aMCatNLO ?

Thanks a lot in advance

Best
Hannes

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Solved by:
Olivier Mattelaer
Solved:
2020-12-03
Last query:
2020-12-03
Last reply:
2020-12-03
Best Olivier Mattelaer (olivier-mattelaer) said : #1

Hi,

We do not have the running of alpha_ew in our code.
It should be possible to modify the UFO model in a future release to include (massless RGE) but this is not yet public.

Cheers,

Olivier

> On 3 Dec 2020, at 08:45, Hannes Jung <email address hidden> wrote:
>
> New question #694322 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/694322
>
> Dear aMCatNLO experts
>
> for processes where a DY pair is produced, the QED coupling plays a big role.
> I was wondering whether and how one can switch from a fixed to a running QED coupling (and vice versa).
> Is running alpha_em default in madgraph_aMCatNLO ?
>
> Thanks a lot in advance
>
> Best
> Hannes
>
>
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hannes Jung (hannes.jung) said : #2

Thanks Olivier Mattelaer, that solved my question.