generating SM 4j+MET background

Dear Shiba,

It really depends of the cut that you apply at analysis cut.
I would suggest to find a CMS/ATLAS analysis looking at similar final state and start by generating the same sample.
(and think if you need some additional one)

For example, you might need to generate
p p > j j j j
since the PS/detector effect will also induce some MET in that final state (but no idea if this is relevant to you or not)

Cheers,

Olivier

> On Jan 20, 2016, at 04:52, shibasipu <email address hidden> wrote:
>
> New question #281214 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/281214
>
> Dear Olivier,
> I am generating the SM 4j+MET background for few processes in the following way.
>
> 1. generate p p > w+ j j j j , ( w+ > l+ vl )
>
> 2. generate p p > z j j j j , ( z > vl vl~ )
>
>
> Is it the right way go generate the process in MG5 ?
>
>
>
>
> Regards,
> Shiba
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Thanks Olivier. Actually, I am looking both ATLAS and CMS analyses for the 4j+MET final states.

Yes, you are right that I have to consider p p > j j j j also. But I want to know whether the following commands are the right way to generate the multijet final states in MG5 or not ?

1. generate p p > w+ j j j j , ( w+ > l+ vl )

2. generate p p > z j j j j , ( z > vl vl~ )

3. generate p p > j j j j ,

Regards,
Shiba

You do not need the comma for the third
> generate p p > w+ j j j j , ( w+ > l+ vl )
> generate p p > z j j j j , ( z > vl vl~ )
> generate p p > j j j j

Note that this is pure QCD jet, this does not include QED jet (like a W decaying into two jet)
If this is not what you want then you need to add QED=99 before the comma, at the end of the line for the third line

Cheers,

Olivier

> On Jan 20, 2016, at 09:12, shibasipu <email address hidden> wrote:
>
> Question #281214 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/281214
>
> Status: Answered => Open
>
> shibasipu is still having a problem:
> Thanks Olivier. Actually, I am looking both ATLAS and CMS analyses for
> the 4j+MET final states.
>
> Yes, you are right that I have to consider p p > j j j j also. But I
> want to know whether the following commands are the right way to
> generate the multijet final states in MG5 or not ?
>
> 1. generate p p > w+ j j j j , ( w+ > l+ vl )
>
> 2. generate p p > z j j j j , ( z > vl vl~ )
>
> 3. generate p p > j j j j ,
>
>
> Regards,
> Shiba
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi Olivier,
                     Thanks. I need another clarification. Like for the process 3, do I need to specify the coupling order for the process 1 and the process 2 ?

Regards,
Shiba

If you only want QCD jet then no, otherwise yes.
> On Jan 21, 2016, at 09:07, shibasipu <email address hidden> wrote:
>
> Question #281214 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/281214
>
> Status: Answered => Open
>
> shibasipu is still having a problem:
> Hi Olivier,
> Thanks. I need another clarification. Like for the process 3, do I need to specify the coupling order for the process 1 and the process 2 ?
>
>
>
>
> Regards,
> Shiba
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Thanks. How are you naming jet as QCD jet or QED jet ? I think if one jet is coming from a QCD vertex, you are calling it as QCD jet. Similarly, if one jet is coming from a QED vertex, you are calling it as QED jet. Is not it ?

Regards,
Shiba

Exactly
> On Jan 21, 2016, at 11:33, shibasipu <email address hidden> wrote:
>
> Question #281214 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/281214
>
> Status: Answered => Open
>
> shibasipu is still having a problem:
> Thanks. How are you naming jet as QCD jet or QED jet ? I think if one
> jet is coming from a QCD vertex, you are calling it as QCD jet.
> Similarly, if one jet is coming from a QED vertex, you are calling it
> as QED jet. Is not it ?
>
>
>
>
>
> Regards,
> Shiba
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi Olivier,
                    Thanks. Now I need another few clarifications.

1. Why have you mentioned that I should use exactly QED = 99 for QED jets to be considered ? Even if I consider much more lower order than QED = 99 , MG5 gives equal no. of diagrams as of QED = 99.

2. Suppose I want 4j+MET in SM for both QCD jet and QED jet . Then the correct way to generate the process is :

generate p p > z j j j j QED = 99 , ( z > vl vl~ ). Is it correct ?

Regards,
Shiba

Hi,

> 1. Why have you mentioned that I should use exactly QED = 99 for QED
> jets to be considered ? Even if I consider much more lower order than
> QED = 99 , MG5 gives equal no. of diagrams as of QED = 99.

You can use the number that you want. 99 is just the number that I use (because it was the MG4 default).
Actually I should advise to use QED<=99, this has the same meaning as QED=99 but it is much more clear.

> 2. Suppose I want 4j+MET in SM for both QCD jet and QED jet . Then the correct way to generate the process is :
>
> generate p p > z j j j j QED = 99 , ( z > vl vl~ ). Is it
> correct ?

Yes (but you still have to add the other type of processes leading to that.

Cheers,

Olivier

> On Jan 21, 2016, at 13:57, shibasipu <email address hidden> wrote:
>
> Question #281214 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/281214
>
> Status: Answered => Open
>
> shibasipu is still having a problem:
> Hi Olivier,
> Thanks. Now I need another few clarifications.
>
> 1. Why have you mentioned that I should use exactly QED = 99 for QED
> jets to be considered ? Even if I consider much more lower order than
> QED = 99 , MG5 gives equal no. of diagrams as of QED = 99.
>
>
> 2. Suppose I want 4j+MET in SM for both QCD jet and QED jet . Then the correct way to generate the process is :
>
> generate p p > z j j j j QED = 99 , ( z > vl vl~ ). Is it
> correct ?
>
>
>
> Regards,
> Shiba
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.