MadGraph5_aMC@NLO

Check the value of the PDF used by MG in the integration

Asked by HaolinLi

Hello,

I found a discrepancy between the cross-sections calculated by MG and by my analytical approach.
I have verified that the partonic cross-sections from the two methods agree with each other, so I suspect the discrepancy is due to the PDF, though I have already set the PDF in the two methods to the same one with the same scale dependence.
Therefore, I wonder whether there is some way to monitor the value of the PDF during the integration in the MG so that I can compare it with mine numerically.

Thanks,
Haolin

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Olivier Mattelaer
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Best Olivier Mattelaer (olivier-mattelaer) said : 		#1

Hi,

You can add print statement within the code (in Source/PDF)

Cheers,

Olivier

> On 31 May 2022, at 18:01, HaolinLi <email address hidden> wrote:
>
> New question #702022 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/702022
>
> Hello,
>
> I found a discrepancy between the cross-sections calculated by MG and by my analytical approach.
> I have verified that the partonic cross-sections from the two methods agree with each other, so I suspect the discrepancy is due to the PDF, though I have already set the PDF in the two methods to the same one with the same scale dependence.
> Therefore, I wonder whether there is some way to monitor the value of the PDF during the integration in the MG so that I can compare it with mine numerically.
>
> Thanks,
> Haolin
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Revision history for this message
HaolinLi (lihaolin1991) said : 		#2

Thanks Olivier Mattelaer, that solved my question.