Higgs produced by gluon fusion and decays to a long lived particle

Asked by Ameir Shaa on 2018-10-23

Hi,

I am trying to produce a Higgs boson (h) by gluon (g) fusion and then decay said Higgs to two long lived particles (X).

So the MG5 syntax would be something like:

generate g g > h > X X

I would assume the cross-sections would change as the mass and width of X are changed.

Before I proceed with the creation of such a model, I would like to ask if such a model is already present. If so, what is it and what is X in that model?

Many thanks,

Ameir

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
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Solved by:
Ameir Shaa
Solved:
2018-10-24
Last query:
2018-10-24
Last reply:
2018-10-23

Hi,

I do not know,
each peace should already exists
g g > h, you can use the heft model (if your X mass is below half top mass of course, otherwise you will need loop induced process)

for h > X X
They should be a lot of BSM model with exotic decay for the Higgs (or you can look at Dark Matter model)
in that case X can basically be anything you want (scalar, fermion, ...)
making him near stable should not be an issue.
You should check the feynrules database and start from those lagrangians.
If you are not sure about the content of a model, you can contact the author of that particular model.
If you need more help on which model exists or not, you can contact the FR authors.

Cheers,

Olivier

> On 23 Oct 2018, at 20:37, Ameir Shaa <email address hidden> wrote:
>
> New question #675497 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/675497
>
> Hi,
>
> I am trying to produce a Higgs boson (h) by gluon (g) fusion and then decay said Higgs to two long lived particles (X).
>
> So the MG5 syntax would be something like:
>
> generate g g > h > X X
>
> I would assume the cross-sections would change as the mass and width of X are changed.
>
> Before I proceed with the creation of such a model, I would like to ask if such a model is already present. If so, what is it and what is X in that model?
>
> Many thanks,
>
> Ameir
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Ameir Shaa (ameirshaa) said : #2

Hi Olivier,

Many thanks for your reply!

If I were to use two models, say heft and a dark matter model, is there a way I can “combine” the two models?

Many thanks,

Ameir

At FeynRules level, you sum the Lagrangian and then run FR, this sounds trivial (at the same time I'm not a FR expert)

Now this particular merging heft +BSM is actually possible to perform at MG5aMC level as well via the command
import model XXXXX
add model hgg_plugin --output=YYYYYY

Then you will have a new YYYYYY directory with the UFO format and you can check if it works as you expect.

Cheers,

Olivier

> On 23 Oct 2018, at 21:02, Ameir Shaa <email address hidden> wrote:
>
> Question #675497 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/675497
>
> Status: Answered => Open
>
> Ameir Shaa is still having a problem:
> Hi Olivier,
>
> Many thanks for your reply!
>
> If I were to use two models, say heft and a dark matter model, is there
> a way I can “combine” the two models?
>
> Many thanks,
>
> Ameir
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Ameir Shaa (ameirshaa) said : #4

Hi Olivier,

Many thanks for your answer! That helped alot! :)

Many thanks,

Ameir