MadGraph5_aMC@NLO

HEFT model and QED order

Asked by Andre Sznajder

I am generating the process bellow using the HEFT model , which I assume will always involve a Higgs coupled to a pair of initial state gluons:

generate p p > Z Z QED=3 QCD=0 , Z > e+ e- , Z > mu+ mu-

My understanding is that QED=3 is the maximal QED order allowed in the process , so why I am also getting diagrams for the processes bellow which are QED=4 and don't belong to HEFT ?

 u u~ > e+ e- mu+ mu- , d d~ > e+ e- mu+ mu- ...

I am running Madgraph v2_3_0 on a Mac OSX Yosemite v10.10.4 with gcc4.2.1 and python 2.7.6.

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Olivier Mattelaer (olivier-mattelaer) said : 		#1

Dear Andre,

Your restriction applies only to the production process, and not to the decay.
Since your decay are QED, it adds two QED order to the final diagram.

Cheers,

Olivier

On 09 Aug 2015, at 18:31, Andre Sznajder <email address hidden> wrote:

> New question #270161 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/270161
>
> I am generating the process bellow using the HEFT model , which I assume will always involve a Higgs coupled to a pair of initial state gluons:
>
> generate p p > Z Z QED=3 QCD=0 , Z > e+ e- , Z > mu+ mu-
>
> My understanding is that QED=3 is the maximal QED order allowed in the process , so why I am also getting diagrams for the processes bellow which are QED=4 and don't belong to HEFT ?
>
> u u~ > e+ e- mu+ mu- , d d~ > e+ e- mu+ mu- ...
>
> I am running Madgraph v2_3_0 on a Mac OSX Yosemite v10.10.4 with gcc4.2.1 and python 2.7.6.
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

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