Changing the PDF scale

Dear Arindam,

You have two ways of doing that:
1) with a file like
launch
set scalefact 0.1
launch
 set scalefact 0.1
and run it like ./bin/madevent PATH

This is slow and inefficient

2) by using syscalc
-install SysCalc (and potentially lhapdf6 and all the pdfset that you will need)
(to install syscalc you can use “install SysCalc” in MG5)

- in the run_card set the parameter
0.5 1 2 = sys_scalefact
to
0.1 0.2 0.3 ….

- add the line (in the run_card)
 -2 = sys_scalecorrelation # -2 is only correlated correlation between muF and muR
                                          # -1 means all possible combination between muF and muR
Then run as usual.
Then you will get the answer that you need much quicker (the computation is done by reweighting)

Cheers,

Olivier

> On Jan 17, 2016, at 22:16, Arindam Das <email address hidden> wrote:
>
> New question #281103 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/281103
>
> Hi MadGraph Team,
>
> I want to vary the renormalization and the factorization scales
> of the PDF.
> The scale factor will vary from 0.1 to 10. The step size is 0.1 up to 1 and from 1 to 10 in a step of 1.
> Is there a way to use the command , scan : [....] ?
> Or any other command to use the automatic scan option ?
>
> Regards,
> Arindam
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.