Interference for two Higgses in z-decay

Hi,

My guess is that those two diagram forms a gauge invariant subset so it should be fine.
But I would advise you to convince yourself that this is indeed the case.

Now your commands has a third diagram with a Z going to b b~ (and radiation of the h3 from the Z).
So I guess that the syntax that you are looking for is
> generate z > b b~ h3 $$ b b~ z

Cheers,

Olivier

> On Oct 25, 2016, at 10:07, lily <email address hidden> wrote:
>
> New question #403433 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/403433
>
> Dear authors,
>
> I am studying the interference effects of h1 and h2 in Z -> b b~ h3 in 2HDM. h1 and h2 are the CP-even Higgses and h3 is the CP-odd Higgs. The diagrams of Z -> b b~ h3 in the CP conservation 2HDM includes
>
> 1. Z -> h3 h2 (h2-> b b~)
> 2. Z -> h3 h1 (h1->b b~)
> 3. Z -> b b~ h3 (b or b~ in the s-channel)
>
> I only want to consider the contributions of h1 and h2 to Z -> b b~ h3, including their interference effects. The third process need be deleted. Therefore, I input the following commands:
>
> import model 2HDM
> define bmp = b b~
> generate z > b b~ h3 $$ bmp
>
> Are these commands right? Are any un-physical contributions obtained?
>
> Best,
> Lily
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi Olivier,

Many thanks for your reply.

If those two diagram containing h1 and h2 are not gauge invariant , can the mg5 give some reports on error or warning?

Best,
Lily

Hi,

No everything will go trough but your result will simply be non physical (since it will be gauge dependent)
Your result will also not be lorentz invariant but that’s a detail in such situation.

The only suggestion is to use the “check” function of MG5 in order to check the validity of the process.
This does not guarantee anything but is a minimal check that you can do.

Cheers,

Olivier

PS: you can use help check for instructions

> On Oct 25, 2016, at 10:53, lily <email address hidden> wrote:
>
> Question #403433 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/403433
>
> Status: Answered => Open
>
> lily is still having a problem:
> Hi Olivier,
>
> Many thanks for your reply.
>
> If those two diagram containing h1 and h2 are not gauge invariant , can
> the mg5 give some reports on error or warning?
>
> Best,
> Lily
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.