Central Exclusive ttbar Production

Asked by Silvano Tosi on 2018-02-02

Dear all

I'd like to generate events of the form proton-proton -> proton t tbar proton, where the two protons will be reconstructed by ad-hoc forward detectors.

The main contribution should come from the gamma gamma -> ttbar diagram. To get this, I am generating the subprocess a a > t t~ in the SM with Madgraph5.
In the run_card.dat I have chosen the collider type option 2 for both beams:
          2 = lpp1 ! beam 1 type
          2 = lpp2 ! beam 2 type

Everything works fine: I get a reasonable cross section and in the LHE files I get events with the two incoming photons and the outgoing ttbar pair. However, since I am interested in reconstructing also the surviving protons, I'd like the outgoing protons too to appear in the LHE file. How can this be done?
Thanks in advance
Regards
Silvano

Question information

Language:
English Edit question
Status:
Answered
For:
MadGraph5_aMC@NLO Edit question
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Last query:
2018-02-02
Last reply:
2018-02-02

Hi,

You have to create your own code to add such information inside the file.
I would obviously advise you to use existing parser to read/write such type of file.

Cheers,

Olivier

> On 2 Feb 2018, at 11:57, Silvano Tosi <email address hidden> wrote:
>
> New question #663988 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/663988
>
> Dear all
>
> I'd like to generate events of the form proton-proton -> proton t tbar proton, where the two protons will be reconstructed by ad-hoc forward detectors.
>
> The main contribution should come from the gamma gamma -> ttbar diagram. To get this, I am generating the subprocess a a > t t~ in the SM with Madgraph5.
> In the run_card.dat I have chosen the collider type option 2 for both beams:
> 2 = lpp1 ! beam 1 type
> 2 = lpp2 ! beam 2 type
>
> Everything works fine: I get a reasonable cross section and in the LHE files I get events with the two incoming photons and the outgoing ttbar pair. However, since I am interested in reconstructing also the surviving protons, I'd like the outgoing protons too to appear in the LHE file. How can this be done?
> Thanks in advance
> Regards
> Silvano
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

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