choosing xqcut in susy processes

Hi,

If the DJR plot is good then this is ok.

Cheers,

Olivier

On 27 Jul 2015, at 13:36, Juhi Dutta <email address hidden> wrote:

> New question #269700 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/269700
>
> Hi,
>
> I am generating the following processes in MG5_aMC_v2_2_3:
>
> define ups = ul ul~
> generate p p > ups go
>
> In this case I want to see the shower jet ( ISR) highest jet pt distribution only hence I switch off the gluino and up squark decays.
>
> Further I generate
>
> define ups = ul ul~
> generate p p > ups go j
>
> This time I swtich off the ISR , FSR ,the gluino and up squark decays and again see the highest jet PT distribution coming from the hard scattering 2->3 process.
>
> Now in order to choose the correct xqcut I compare the PT(j[1]) plots for the ISR jets from 2->2 and matrix element jet from 2->3 processes. I find they cross each other around ~110-120. The concerned plot is : https://www.dropbox.com/s/rv7ut7r3jrstfbv/PSMEplot.pdf?dl=0
>
> I take this value as xqcut and generate the combined process of :
>
> define ups = ul ul~
> generate p p > ups go @0
> add process p p > ups go j @1
>
> xqcut = 120 in run_card.dat
> QCUT = 120
> SHOWERKT = T in the pythia_card.dat
>
> and see that the generated DJR plot also looks smooth. The DJR plot is : https://www.dropbox.com/s/4jpz5h44xzwnpy1/DJR1.ps?dl=0
>
> I would like to know if this approach to locate the xqcut by comparing the leading parton shower jet from 2->2 and leading jet pt from the hard scattered process is appropriate .Actually the DJR plots were appearing smooth for values of xqcut ranging from 20,40,100,150 so I am not sure which one to chose hence this approach was taken.
>
> Is this a valid way of choosing xqcut? Kindly advise me in this regard.
>
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi,

Thank you for the reply! Yes i think the DJR looks fine for this value. but so does it look for the rest of the QCUT values of 20,40 ,,...upto 150 except the peaks shift to the right with higher QCUTs.

I have read on launchpad and also on some talks and tutorials on matching given by madgraph authors where a rough idea of 1/6 to 1/3 of the hard scale has been suggested. What do we refer to as the hard scale?

Also in the page of Introduction to matching by madgraph (https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/IntroMatching) , for 600 GeV (or more ) gluino QCUT = 100 has been suggested .So in general for SUSY processes are the QCUTs kept higher?

Thanks and Regards,

Juhi

Hi,

> Thank you for the reply! Yes i think the DJR looks fine for this value.
> but so does it look for the rest of the QCUT values of 20,40 ,,...upto
> 150 except the peaks shift to the right with higher QCUTs.

The black curve should (roughly) be the same whatever value of QCUT that you choose.

> So in general
> for SUSY processes are the QCUTs kept higher?

Yes.

Olivier

On 27 Jul 2015, at 14:21, Juhi Dutta <email address hidden> wrote:

> Question #269700 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/269700
>
> Status: Answered => Open
>
> Juhi Dutta is still having a problem:
> Hi,
>
> Thank you for the reply! Yes i think the DJR looks fine for this value.
> but so does it look for the rest of the QCUT values of 20,40 ,,...upto
> 150 except the peaks shift to the right with higher QCUTs.
>
> I have read on launchpad and also on some talks and tutorials on
> matching given by madgraph authors where a rough idea of 1/6 to 1/3 of
> the hard scale has been suggested. What do we refer to as the hard
> scale?
>
> Also in the page of Introduction to matching by madgraph
> (https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/IntroMatching) , for
> 600 GeV (or more ) gluino QCUT = 100 has been suggested .So in general
> for SUSY processes are the QCUTs kept higher?
>
>
> Thanks and Regards,
>
> Juhi
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi,

Ok so as I understand the QCUT is kept higher as the SUSY particles
squarks,gluinos are heavier. Is it true?

I have another question regarding generation of SUSY processes with extra
jets.

define sp = go ul cl t1 ur cr t2 dl sl b1 dr sr b2 ul~ cl~ t1~ ur~ cr~ t2~
dl~ sl~ b1~ dr~ sr~ b2~
generate p p > sp sp @0
add process p p > sp sp j @1

Is this a valid way to deal with associated squark-gluino production with
matched extra jets ? My concern was whether it would match all the
subprocesses correctly as the process 0 and the process 1 might not be for
the same combination of sparticles.

Or should I separately deal with each of the squaks in association with
gluino ?

Thanks and Regards,
Juhi

Sorry I made an error in the earlier question.

I am not just looking for associated squark-gluino production but also all
squark-squark,suark-gluino and gluino-gluino processes upto 1 extra jet.

On Mon, Jul 27, 2015 at 7:21 PM, Juhi Dutta <
<email address hidden>> wrote:

> Your question #269700 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/269700
>
> Status: Answered => Open
>
> You are still having a problem:
> Hi,
>
> Ok so as I understand the QCUT is kept higher as the SUSY particles
> squarks,gluinos are heavier. Is it true?
>
> I have another question regarding generation of SUSY processes with extra
> jets.
>
> define sp = go ul cl t1 ur cr t2 dl sl b1 dr sr b2 ul~ cl~ t1~ ur~ cr~ t2~
> dl~ sl~ b1~ dr~ sr~ b2~
> generate p p > sp sp @0
> add process p p > sp sp j @1
>
> Is this a valid way to deal with associated squark-gluino production with
> matched extra jets ? My concern was whether it would match all the
> subprocesses correctly as the process 0 and the process 1 might not be for
> the same combination of sparticles.
>
> Or should I separately deal with each of the squaks in association with
> gluino ?
>
> Thanks and Regards,
> Juhi
>
> --
> You received this question notification because you asked the question.
>

Hi,

> Ok so as I understand the QCUT is kept higher as the SUSY particles
> squarks,gluinos are heavier. Is it true?

Typically yes.

> Is this a valid way to deal with associated squark-gluino production with
> matched extra jets ?

No you need to forbid the gluino to be resonant.

> generate p p > sp sp @0
> add process p p > sp sp j $ go @1

and add in the pythia card exres = PDG of the gluino.

Cheers,

Olivier

On 27 Jul 2015, at 14:51, Juhi Dutta <email address hidden> wrote:

> Question #269700 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/269700
>
> Status: Answered => Open
>
> Juhi Dutta is still having a problem:
> Hi,
>
> Ok so as I understand the QCUT is kept higher as the SUSY particles
> squarks,gluinos are heavier. Is it true?
>
> I have another question regarding generation of SUSY processes with extra
> jets.
>
> define sp = go ul cl t1 ur cr t2 dl sl b1 dr sr b2 ul~ cl~ t1~ ur~ cr~ t2~
> dl~ sl~ b1~ dr~ sr~ b2~
> generate p p > sp sp @0
> add process p p > sp sp j @1
>
> Is this a valid way to deal with associated squark-gluino production with
> matched extra jets ? My concern was whether it would match all the
> subprocesses correctly as the process 0 and the process 1 might not be for
> the same combination of sparticles.
>
> Or should I separately deal with each of the squaks in association with
> gluino ?
>
> Thanks and Regards,
> Juhi
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi,

Ok yes I forgot to mention I did add EXCRES = PDG of gluino in pythia card
. But I did not use $ go as I thought both have same function. ok I will
correct it.

Also I had added EXCRES = PDG of the squarks in pythia card.Since they
might also be resonant and lead to final states already accounted for ? A
resonant squark may give a quark(j) and gluino which is thus double
counting the process sqk-gluino-j coming also from sqk-gluino-j hard
scattered process .

Thanks and Regards,

Juhi

On Mon, Jul 27, 2015 at 7:31 PM, Olivier Mattelaer <
<email address hidden>> wrote:

> Your question #269700 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/269700
>
> Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> > Ok so as I understand the QCUT is kept higher as the SUSY particles
> > squarks,gluinos are heavier. Is it true?
>
> Typically yes.
>
> > Is this a valid way to deal with associated squark-gluino production with
> > matched extra jets ?
>
> No you need to forbid the gluino to be resonant.
>
>
> > generate p p > sp sp @0
> > add process p p > sp sp j $ go @1
>
>
> and add in the pythia card exres = PDG of the gluino.
>
> Cheers,
>
> Olivier
>
> On 27 Jul 2015, at 14:51, Juhi Dutta
> <email address hidden> wrote:
>
> > Question #269700 on MadGraph5_aMC@NLO changed:
> > https://answers.launchpad.net/mg5amcnlo/+question/269700
> >
> > Status: Answered => Open
> >
> > Juhi Dutta is still having a problem:
> > Hi,
> >
> > Ok so as I understand the QCUT is kept higher as the SUSY particles
> > squarks,gluinos are heavier. Is it true?
> >
> > I have another question regarding generation of SUSY processes with extra
> > jets.
> >
> > define sp = go ul cl t1 ur cr t2 dl sl b1 dr sr b2 ul~ cl~ t1~ ur~ cr~
> t2~
> > dl~ sl~ b1~ dr~ sr~ b2~
> > generate p p > sp sp @0
> > add process p p > sp sp j @1
> >
> > Is this a valid way to deal with associated squark-gluino production with
> > matched extra jets ? My concern was whether it would match all the
> > subprocesses correctly as the process 0 and the process 1 might not be
> for
> > the same combination of sparticles.
> >
> > Or should I separately deal with each of the squaks in association with
> > gluino ?
> >
> > Thanks and Regards,
> > Juhi
> >
> > --
> > You received this question notification because you are an answer
> > contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
>
> https://answers.launchpad.net/mg5amcnlo/+question/269700/+confirm?answer_id=5
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/269700
>
> You received this question notification because you asked the question.
>