Merging cross section

Asked by ouseph cj

I am working on the given process

generate p p > j vl vl~ @0
add process p p > j j vl vl~ @1
add process p p > j j j vl vl~ @2

I got X-section as 2454 pb
and merging cross section
947pb
568pb
400pb

which X- Section that I need to use for the calculation of N = X-Section *Luminosity *acceptance *efficiency.
and why?

Best
Melbin

Question information

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Status:
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For:
MadGraph5_aMC@NLO Edit question
Assignee:
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Solved by:
Olivier Mattelaer
Solved:
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Last reply:
Revision history for this message
Olivier Mattelaer (olivier-mattelaer) said :
#1

Hi,

You can not use "2454" since that one has serious double counting.

For the other three, they are apriori all good/bad. You have to check the DJR plot to see if the removal of the double counting is working well and then you can decide.
In top of that, such removal should be associated to an uncertainty which in your case seems very large.

Note that you are in a difficult case since you have a jet in the lowest multiplicity. Is there any reason for doing that? Did you double check your cut (what is the value auto_ptj_mjj for example)?

Cheers,

Olivier

> On 12 Oct 2020, at 05:10, ouseph cj <email address hidden> wrote:
>
> New question #693409 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/693409
>
> I am working on the given process
>
> generate p p > j vl vl~ @0
> add process p p > j j vl vl~ @1
> add process p p > j j j vl vl~ @2
>
> I got X-section as 2454 pb
> and merging cross section
> 947pb
> 568pb
> 400pb
>
> which X- Section that I need to use for the calculation of N = X-Section *Luminosity *acceptance *efficiency.
> and why?
>
> Best
> Melbin
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Revision history for this message
ouseph cj (ouseph444) said :
#2

Dear Oliver
Thanks for your reply.
I used the default values in the run card for the
analysis,Ptj=20,Xqcut=30,mmjj=0.

Best
ouseph

On Mon, Oct 12, 2020 at 3:01 PM Olivier Mattelaer <
<email address hidden>> wrote:

> Your question #693409 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693409
>
> Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> You can not use "2454" since that one has serious double counting.
>
> For the other three, they are apriori all good/bad. You have to check
> the DJR plot to see if the removal of the double counting is working well
> and then you can decide.
> In top of that, such removal should be associated to an uncertainty which
> in your case seems very large.
>
> Note that you are in a difficult case since you have a jet in the lowest
> multiplicity. Is there any reason for doing that? Did you double check
> your cut (what is the value auto_ptj_mjj for example)?
>
> Cheers,
>
> Olivier
>
>
> > On 12 Oct 2020, at 05:10, ouseph cj <
> <email address hidden>> wrote:
> >
> > New question #693409 on MadGraph5_aMC@NLO:
> > https://answers.launchpad.net/mg5amcnlo/+question/693409
> >
> > I am working on the given process
> >
> > generate p p > j vl vl~ @0
> > add process p p > j j vl vl~ @1
> > add process p p > j j j vl vl~ @2
> >
> > I got X-section as 2454 pb
> > and merging cross section
> > 947pb
> > 568pb
> > 400pb
> >
> > which X- Section that I need to use for the calculation of N = X-Section
> *Luminosity *acceptance *efficiency.
> > and why?
> >
> > Best
> > Melbin
> >
> > --
> > 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/693409/+confirm?answer_id=0
>
> 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/693409
>
> You received this question notification because you asked the question.
>

Revision history for this message
Olivier Mattelaer (olivier-mattelaer) said :
#4

Then I do not see the point to not include the zero jet multiplicity.

If you want to discard such multiplicity, you need at minimum pt cut on at least one jet
(ptj1min) and you need obviously that such cut should be much larger than QCUT (and therefore much larger than xqcut)

Your high dependency in the QCUT variation is likely related to that choice of parameter/process.

Cheers,

Olivier

> On 12 Oct 2020, at 09:45, ouseph cj <email address hidden> wrote:
>
> Question #693409 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693409
>
> Status: Answered => Open
>
> ouseph cj is still having a problem:
> Dear Oliver
> Thanks for your reply.
> I used the default values in the run card for the
> analysis,Ptj=20,Xqcut=30,mmjj=0.
>
> Best
> ouseph
>
>
> On Mon, Oct 12, 2020 at 3:01 PM Olivier Mattelaer <
> <email address hidden>> wrote:
>
>> Your question #693409 on MadGraph5_aMC@NLO changed:
>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>
>> Status: Open => Answered
>>
>> Olivier Mattelaer proposed the following answer:
>> Hi,
>>
>> You can not use "2454" since that one has serious double counting.
>>
>> For the other three, they are apriori all good/bad. You have to check
>> the DJR plot to see if the removal of the double counting is working well
>> and then you can decide.
>> In top of that, such removal should be associated to an uncertainty which
>> in your case seems very large.
>>
>> Note that you are in a difficult case since you have a jet in the lowest
>> multiplicity. Is there any reason for doing that? Did you double check
>> your cut (what is the value auto_ptj_mjj for example)?
>>
>> Cheers,
>>
>> Olivier
>>
>>
>>> On 12 Oct 2020, at 05:10, ouseph cj <
>> <email address hidden>> wrote:
>>>
>>> New question #693409 on MadGraph5_aMC@NLO:
>>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>>
>>> I am working on the given process
>>>
>>> generate p p > j vl vl~ @0
>>> add process p p > j j vl vl~ @1
>>> add process p p > j j j vl vl~ @2
>>>
>>> I got X-section as 2454 pb
>>> and merging cross section
>>> 947pb
>>> 568pb
>>> 400pb
>>>
>>> which X- Section that I need to use for the calculation of N = X-Section
>> *Luminosity *acceptance *efficiency.
>>> and why?
>>>
>>> Best
>>> Melbin
>>>
>>> --
>>> 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/693409/+confirm?answer_id=0
>>
>> 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/693409
>>
>> You received this question notification because you asked the question.
>>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Revision history for this message
ouseph cj (ouseph444) said :
#5

Dear Oliver
What do you mean by mjj , is it the same as min invariant mass of a jet
pair (mmjj)?
I did not find anything related to multiplicity in my run card.
I am attaching my run card with this email. Kindly have a look at it

Best
Ouseph

#*********************************************************************

# MadGraph5_aMC@NLO *

# *

# run_card.dat MadEvent *

# *

# This file is used to set the parameters of the run. *

# *

# Some notation/conventions: *

# *

# Lines starting with a '# ' are info or comments *

# *

# mind the format: value = variable ! comment *

# *

# To display more options, you can type the command: *

# update full_run_card *

#*********************************************************************

#

#*********************************************************************

# Tag name for the run (one word) *

#*********************************************************************

  tag_1 = run_tag ! name of the run

#*********************************************************************

# Number of events and rnd seed *

# Warning: Do not generate more than 1M events in a single run *

#*********************************************************************

  100000 = nevents ! Number of unweighted events requested

  0 = iseed ! rnd seed (0=assigned automatically=default))

#*********************************************************************

# Collider type and energy *

# lpp: 0=No PDF, 1=proton, -1=antiproton, 2=photon from proton, *

# 3=photon from electron *

#*********************************************************************

     1 = lpp1 ! beam 1 type

     1 = lpp2 ! beam 2 type

     6500.0 = ebeam1 ! beam 1 total energy in GeV

     6500.0 = ebeam2 ! beam 2 total energy in GeV

# To see polarised beam options: type "update beam_pol"

#*********************************************************************

# PDF CHOICE: this automatically fixes also alpha_s and its evol. *

#*********************************************************************

     nn23lo1 = pdlabel ! PDF set

     230000 = lhaid ! if pdlabel=lhapdf, this is the lhapdf number

# To see heavy ion options: type "update ion_pdf"

#*********************************************************************

# Renormalization and factorization scales *

#*********************************************************************

 False = fixed_ren_scale ! if .true. use fixed ren scale

 False = fixed_fac_scale ! if .true. use fixed fac scale

 91.188 = scale ! fixed ren scale

 91.188 = dsqrt_q2fact1 ! fixed fact scale for pdf1

 91.188 = dsqrt_q2fact2 ! fixed fact scale for pdf2

 -1 = dynamical_scale_choice ! Choose one of the preselected dynamical
choices

 1.0 = scalefact ! scale factor for event-by-event scales

#*********************************************************************

# Type and output format

#*********************************************************************

  False = gridpack !True = setting up the grid pack

  -1.0 = time_of_flight ! threshold (in mm) below which the invariant
livetime is not written (-1 means not written)

  average = event_norm ! average/sum. Normalization of the weight in
the LHEF

#*********************************************************************

# Matching parameter (MLM only) 1 = ickkw ! 0 no matching, 1 MLM

 1.0 = alpsfact ! scale factor for QCD emission vx

 False = chcluster ! cluster only according to channel diag

 4 = asrwgtflavor ! highest quark flavor for a_s reweight

 True = auto_ptj_mjj ! Automatic setting of ptj and mjj if xqcut >0

                                   ! (turn off for VBF and single top
processes)

 30.0 = xqcut ! minimum kt jet measure between partons

#***********************************************************************

# Turn on either the ktdurham or ptlund cut to activate *

# CKKW(L) merging with Pythia8 [arXiv:1410.3012, arXiv:1109.4829] *

#***********************************************************************

 -1.0 = ktdurham

 0.4 = dparameter

 -1.0 = ptlund

 1, 2, 3, 4, 5, 6, 21 = pdgs_for_merging_cut ! PDGs for two cuts above

#*********************************************************************

#

#*********************************************************************

# handling of the helicities:

# 0: sum over all helicities

# 1: importance sampling over helicities

#*********************************************************************

   0 = nhel ! using helicities importance sampling or not.

#*********************************************************************

# Generation bias, check the wiki page below for more information: *

# 'cp3.irmp.ucl.ac.be/projects/madgraph/wiki/LOEventGenerationBias' *

#*********************************************************************

 None = bias_module ! Bias type of bias, [None, ptj_bias, -custom_folder-]

 {} = bias_parameters ! Specifies the parameters of the module.

#

#*******************************

# Parton level cuts definition *

#*******************************

#

#

#*********************************************************************

# BW cutoff (M+/-bwcutoff*Gamma) ! Define on/off-shell for "$" and decay

#*********************************************************************

  15.0 = bwcutoff ! (M+/-bwcutoff*Gamma)

#*********************************************************************

# Standard Cuts *

#*********************************************************************

# Minimum and maximum pt's (for max, -1 means no cut) *

#*********************************************************************

 20.0 = ptj ! minimum pt for the jets

 0.0 = misset ! minimum missing Et (sum of neutrino's momenta)

 -1.0 = ptjmax ! maximum pt for the jets

 -1.0 = missetmax ! maximum missing Et (sum of neutrino's momenta)

 {} = pt_min_pdg ! pt cut for other particles (use pdg code). Applied on
particle and anti-particle

 {} = pt_max_pdg ! pt cut for other particles (syntax e.g. {6: 100, 25:
50})

#

# For display option for energy cut in the partonic center of mass frame
type 'update ecut'

#

#*********************************************************************

# Maximum and minimum absolute rapidity (for max, -1 means no cut) *

#*********************************************************************

 5.0 = etaj ! max rap for the jets{} = eta_min_pdg ! rap cut for other
particles (use pdg code). Applied on particle and anti-particle

 {} = eta_max_pdg ! rap cut for other particles (syntax e.g. {6: 2.5, 23:
5})

#*********************************************************************

# Minimum and maximum DeltaR distance *

#*********************************************************************

 0.0 = drjj ! min distance between jets

 -1.0 = drjjmax ! max distance between jets

#*********************************************************************

# Minimum and maximum invariant mass for pairs *

#*********************************************************************

 0.0 = mmjj ! min invariant mass of a jet pair

 -1.0 = mmjjmax ! max invariant mass of a jet pair

 {} = mxx_min_pdg ! min invariant mass of a pair of particles X/X~ (e.g.
{6:250})

 {'default': False} = mxx_only_part_antipart ! if True the invariant mass
is applied only

                       ! to pairs of particle/antiparticle and not to pairs
of the same pdg codes.

 #*********************************************************************

 # Minimum and maximum invariant mass for all letpons *

 #*********************************************************************

 0.0 = mmnl ! min invariant mass for all letpons (l+- and vl)

 -1.0 = mmnlmax ! max invariant mass for all letpons (l+- and vl)

 #*********************************************************************

 # Minimum and maximum pt for 4-momenta sum of leptons *

 #*********************************************************************

#*********************************************************************

# Inclusive cuts *

#*********************************************************************

 0.0 = xptj ! minimum pt for at least one jet

 #*********************************************************************

 # Control the pt's of the jets sorted by pt *

 #*********************************************************************

 0.0 = ptj1min ! minimum pt for the leading jet in pt

 0.0 = ptj2min ! minimum pt for the second jet in pt

 0.0 = ptj3min ! minimum pt for the third jet in pt

 -1.0 = ptj1max ! maximum pt for the leading jet in pt

 -1.0 = ptj2max ! maximum pt for the second jet in pt

 -1.0 = ptj3max ! maximum pt for the third jet in pt

 0 = cutuse ! reject event if fails any (0) / all (1) jet pt cuts

 #*********************************************************************

 # Control the Ht(k)=Sum of k leading jets *

 #*********************************************************************

 0.0 = htjmin ! minimum jet HT=Sum(jet pt)

 -1.0 = htjmax ! maximum jet HT=Sum(jet pt)

 0.0 = ihtmin !inclusive Ht for all partons (including b)

 -1.0 = ihtmax !inclusive Ht for all partons (including b)

 0.0 = ht2min ! minimum Ht for the two leading jets

 0.0 = ht3min ! minimum Ht for the three leading jets

 -1.0 = ht2max ! maximum Ht for the two leading jets

 -1.0 = ht3max ! maximum Ht for the three leading jets

 #*********************************************************************

 # WBF cuts *

 #*********************************************************************

 0.0 = xetamin ! minimum rapidity for two jets in the WBF case

 0.0 = deltaeta ! minimum rapidity for two jets in the WBF case

#*********************************************************************

# maximal pdg code for quark to be considered as a light jet *

# (otherwise b cuts are applied) *

#*********************************************************************

 4 = maxjetflavor ! Maximum jet pdg code

#*********************************************************************

#

#*********************************************************************

#

#*********************************************************************

# Store info for systematics studies *

# WARNING: Do not use for interference type of computation *

#*********************************************************************

   True = use_syst ! Enable systematics studies

#

systematics = systematics_program ! none, systematics [python], SysCalc
[depreceted, C++]

['--mur=0.5,1,2', '--muf=0.5,1,2', '--pdf=errorset', '--alps=0.5,1,2'] =
systematics_arguments ! see:
https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/Systematics#Systematicspythonmodule

# Syscalc is deprecated but to see the associate options type'update
syscalc'177,1 93%

On Mon, Oct 12, 2020 at 4:01 PM Olivier Mattelaer <
<email address hidden>> wrote:

> Your question #693409 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693409
>
> Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Then I do not see the point to not include the zero jet multiplicity.
>
> If you want to discard such multiplicity, you need at minimum pt cut on at
> least one jet
> (ptj1min) and you need obviously that such cut should be much larger than
> QCUT (and therefore much larger than xqcut)
>
> Your high dependency in the QCUT variation is likely related to that
> choice of parameter/process.
>
> Cheers,
>
> Olivier
>
> > On 12 Oct 2020, at 09:45, ouseph cj <
> <email address hidden>> wrote:
> >
> > Question #693409 on MadGraph5_aMC@NLO changed:
> > https://answers.launchpad.net/mg5amcnlo/+question/693409
> >
> > Status: Answered => Open
> >
> > ouseph cj is still having a problem:
> > Dear Oliver
> > Thanks for your reply.
> > I used the default values in the run card for the
> > analysis,Ptj=20,Xqcut=30,mmjj=0.
> >
> > Best
> > ouseph
> >
> >
> > On Mon, Oct 12, 2020 at 3:01 PM Olivier Mattelaer <
> > <email address hidden>> wrote:
> >
> >> Your question #693409 on MadGraph5_aMC@NLO changed:
> >> https://answers.launchpad.net/mg5amcnlo/+question/693409
> >>
> >> Status: Open => Answered
> >>
> >> Olivier Mattelaer proposed the following answer:
> >> Hi,
> >>
> >> You can not use "2454" since that one has serious double counting.
> >>
> >> For the other three, they are apriori all good/bad. You have to check
> >> the DJR plot to see if the removal of the double counting is working
> well
> >> and then you can decide.
> >> In top of that, such removal should be associated to an uncertainty
> which
> >> in your case seems very large.
> >>
> >> Note that you are in a difficult case since you have a jet in the lowest
> >> multiplicity. Is there any reason for doing that? Did you double check
> >> your cut (what is the value auto_ptj_mjj for example)?
> >>
> >> Cheers,
> >>
> >> Olivier
> >>
> >>
> >>> On 12 Oct 2020, at 05:10, ouseph cj <
> >> <email address hidden>> wrote:
> >>>
> >>> New question #693409 on MadGraph5_aMC@NLO:
> >>> https://answers.launchpad.net/mg5amcnlo/+question/693409
> >>>
> >>> I am working on the given process
> >>>
> >>> generate p p > j vl vl~ @0
> >>> add process p p > j j vl vl~ @1
> >>> add process p p > j j j vl vl~ @2
> >>>
> >>> I got X-section as 2454 pb
> >>> and merging cross section
> >>> 947pb
> >>> 568pb
> >>> 400pb
> >>>
> >>> which X- Section that I need to use for the calculation of N =
> X-Section
> >> *Luminosity *acceptance *efficiency.
> >>> and why?
> >>>
> >>> Best
> >>> Melbin
> >>>
> >>> --
> >>> 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/693409/+confirm?answer_id=0
> >>
> >> 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/693409
> >>
> >> You received this question notification because you asked the question.
> >>
> >
> > --
> > 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/693409/+confirm?answer_id=3
>
> 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/693409
>
> You received this question notification because you asked the question.
>

Revision history for this message
Best Olivier Mattelaer (olivier-mattelaer) said :
#6

I guess that you do not know the details of MLM method to remove douuble-counting.

I would suggest to check those slides:
file:///Users/omattelaer/Downloads/Milan_merging.pdf

and the read the associated paper (and check CKKW-L method as well)

Cheers,

Olivier

> On 12 Oct 2020, at 10:01, ouseph cj <email address hidden> wrote:
>
> Question #693409 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693409
>
> ouseph cj gave more information on the question:
> Dear Oliver
> What is the problem? Could you please help me to understand what is wrong
> in the Cards?
>
> Best regards
> Ouseph
>
>
> On Mon, Oct 12, 2020 at 3:45 PM ouseph cj <
> <email address hidden>> wrote:
>
>> Your question #693409 on MadGraph5_aMC@NLO changed:
>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>
>> Status: Answered => Open
>>
>> You are still having a problem:
>> Dear Oliver
>> Thanks for your reply.
>> I used the default values in the run card for the
>> analysis,Ptj=20,Xqcut=30,mmjj=0.
>>
>> Best
>> ouseph
>>
>>
>> On Mon, Oct 12, 2020 at 3:01 PM Olivier Mattelaer <
>> <email address hidden>> wrote:
>>
>>> Your question #693409 on MadGraph5_aMC@NLO changed:
>>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>>
>>> Status: Open => Answered
>>>
>>> Olivier Mattelaer proposed the following answer:
>>> Hi,
>>>
>>> You can not use "2454" since that one has serious double counting.
>>>
>>> For the other three, they are apriori all good/bad. You have to check
>>> the DJR plot to see if the removal of the double counting is working well
>>> and then you can decide.
>>> In top of that, such removal should be associated to an uncertainty which
>>> in your case seems very large.
>>>
>>> Note that you are in a difficult case since you have a jet in the lowest
>>> multiplicity. Is there any reason for doing that? Did you double check
>>> your cut (what is the value auto_ptj_mjj for example)?
>>>
>>> Cheers,
>>>
>>> Olivier
>>>
>>>
>>>> On 12 Oct 2020, at 05:10, ouseph cj <
>>> <email address hidden>> wrote:
>>>>
>>>> New question #693409 on MadGraph5_aMC@NLO:
>>>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>>>
>>>> I am working on the given process
>>>>
>>>> generate p p > j vl vl~ @0
>>>> add process p p > j j vl vl~ @1
>>>> add process p p > j j j vl vl~ @2
>>>>
>>>> I got X-section as 2454 pb
>>>> and merging cross section
>>>> 947pb
>>>> 568pb
>>>> 400pb
>>>>
>>>> which X- Section that I need to use for the calculation of N =
>> X-Section
>>> *Luminosity *acceptance *efficiency.
>>>> and why?
>>>>
>>>> Best
>>>> Melbin
>>>>
>>>> --
>>>> 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/693409/+confirm?answer_id=0
>>>
>>> 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/693409
>>>
>>> You received this question notification because you asked the question.
>>>
>>
>> --
>> You received this question notification because you asked the question.
>>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Revision history for this message
Olivier Mattelaer (olivier-mattelaer) said :
#7

HI,

I was refering to those line in the run_card

True = auto_ptj_mjj ! Automatic setting of ptj and mjj if xqcut >0

                                  ! (turn off for VBF and single top

Cheers,

Olivier

> On 12 Oct 2020, at 10:25, ouseph cj <email address hidden> wrote:
>
> True = auto_ptj_mjj ! Automatic setting of ptj and mjj if xqcut >0
>
> ! (turn off for VBF and single top

Revision history for this message
Olivier Mattelaer (olivier-mattelaer) said :
#8

You can also check this youtube video from our last MG5 school:
https://www.youtube.com/watch?v=dju5Q5GEkuM <https://www.youtube.com/watch?v=dju5Q5GEkuM>
(and given by a pythia8 author)

Cheers,

Olivier

> On 12 Oct 2020, at 10:25, ouseph cj <email address hidden> wrote:
>
> Question #693409 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693409
>
> Status: Answered => Open
>
> ouseph cj is still having a problem:
> Dear Oliver
> What do you mean by mjj , is it the same as min invariant mass of a jet
> pair (mmjj)?
> I did not find anything related to multiplicity in my run card.
> I am attaching my run card with this email. Kindly have a look at it
>
>
> Best
> Ouseph
>
> #*********************************************************************
>
> # MadGraph5_aMC@NLO *
>
> # *
>
> # run_card.dat MadEvent *
>
> # *
>
> # This file is used to set the parameters of the run. *
>
> # *
>
> # Some notation/conventions: *
>
> # *
>
> # Lines starting with a '# ' are info or comments *
>
> # *
>
> # mind the format: value = variable ! comment *
>
> # *
>
> # To display more options, you can type the command: *
>
> # update full_run_card *
>
> #*********************************************************************
>
> #
>
> #*********************************************************************
>
> # Tag name for the run (one word) *
>
> #*********************************************************************
>
> tag_1 = run_tag ! name of the run
>
> #*********************************************************************
>
> # Number of events and rnd seed *
>
> # Warning: Do not generate more than 1M events in a single run *
>
> #*********************************************************************
>
> 100000 = nevents ! Number of unweighted events requested
>
> 0 = iseed ! rnd seed (0=assigned automatically=default))
>
> #*********************************************************************
>
> # Collider type and energy *
>
> # lpp: 0=No PDF, 1=proton, -1=antiproton, 2=photon from proton, *
>
> # 3=photon from electron *
>
> #*********************************************************************
>
> 1 = lpp1 ! beam 1 type
>
> 1 = lpp2 ! beam 2 type
>
> 6500.0 = ebeam1 ! beam 1 total energy in GeV
>
> 6500.0 = ebeam2 ! beam 2 total energy in GeV
>
> # To see polarised beam options: type "update beam_pol"
>
>
> #*********************************************************************
>
> # PDF CHOICE: this automatically fixes also alpha_s and its evol. *
>
> #*********************************************************************
>
> nn23lo1 = pdlabel ! PDF set
>
> 230000 = lhaid ! if pdlabel=lhapdf, this is the lhapdf
> number
>
> # To see heavy ion options: type "update ion_pdf"
>
> #*********************************************************************
>
> # Renormalization and factorization scales *
>
> #*********************************************************************
>
> False = fixed_ren_scale ! if .true. use fixed ren scale
>
> False = fixed_fac_scale ! if .true. use fixed fac scale
>
> 91.188 = scale ! fixed ren scale
>
> 91.188 = dsqrt_q2fact1 ! fixed fact scale for pdf1
>
> 91.188 = dsqrt_q2fact2 ! fixed fact scale for pdf2
>
> -1 = dynamical_scale_choice ! Choose one of the preselected dynamical
> choices
>
> 1.0 = scalefact ! scale factor for event-by-event scales
>
> #*********************************************************************
>
> # Type and output format
>
> #*********************************************************************
>
> False = gridpack !True = setting up the grid pack
>
> -1.0 = time_of_flight ! threshold (in mm) below which the invariant
> livetime is not written (-1 means not written)
>
> average = event_norm ! average/sum. Normalization of the weight in
> the LHEF
>
> #*********************************************************************
>
> # Matching parameter (MLM only) 1 = ickkw ! 0 no matching, 1
> MLM
>
> 1.0 = alpsfact ! scale factor for QCD emission vx
>
> False = chcluster ! cluster only according to channel diag
>
> 4 = asrwgtflavor ! highest quark flavor for a_s reweight
>
> True = auto_ptj_mjj ! Automatic setting of ptj and mjj if xqcut >0
>
> ! (turn off for VBF and single top
> processes)
>
> 30.0 = xqcut ! minimum kt jet measure between partons
>
>
> #***********************************************************************
>
> # Turn on either the ktdurham or ptlund cut to activate *
>
> # CKKW(L) merging with Pythia8 [arXiv:1410.3012, arXiv:1109.4829] *
>
> #***********************************************************************
>
> -1.0 = ktdurham
>
> 0.4 = dparameter
>
> -1.0 = ptlund
>
> 1, 2, 3, 4, 5, 6, 21 = pdgs_for_merging_cut ! PDGs for two cuts above
>
>
> #*********************************************************************
>
> #
>
> #*********************************************************************
>
> # handling of the helicities:
>
> # 0: sum over all helicities
>
> # 1: importance sampling over helicities
>
> #*********************************************************************
>
> 0 = nhel ! using helicities importance sampling or not.
>
> #*********************************************************************
>
> # Generation bias, check the wiki page below for more information: *
>
> # 'cp3.irmp.ucl.ac.be/projects/madgraph/wiki/LOEventGenerationBias' *
>
> #*********************************************************************
>
> None = bias_module ! Bias type of bias, [None, ptj_bias,
> -custom_folder-]
>
> {} = bias_parameters ! Specifies the parameters of the module.
>
> #
>
> #*******************************
>
>
> # Parton level cuts definition *
>
> #*******************************
>
> #
>
> #
>
> #*********************************************************************
>
> # BW cutoff (M+/-bwcutoff*Gamma) ! Define on/off-shell for "$" and decay
>
> #*********************************************************************
>
> 15.0 = bwcutoff ! (M+/-bwcutoff*Gamma)
>
> #*********************************************************************
>
> # Standard Cuts *
>
> #*********************************************************************
>
> # Minimum and maximum pt's (for max, -1 means no cut) *
>
> #*********************************************************************
>
> 20.0 = ptj ! minimum pt for the jets
>
> 0.0 = misset ! minimum missing Et (sum of neutrino's momenta)
>
> -1.0 = ptjmax ! maximum pt for the jets
>
> -1.0 = missetmax ! maximum missing Et (sum of neutrino's momenta)
>
> {} = pt_min_pdg ! pt cut for other particles (use pdg code). Applied on
> particle and anti-particle
>
> {} = pt_max_pdg ! pt cut for other particles (syntax e.g. {6: 100, 25:
> 50})
>
> #
>
> # For display option for energy cut in the partonic center of mass frame
> type 'update ecut'
>
> #
>
> #*********************************************************************
>
> # Maximum and minimum absolute rapidity (for max, -1 means no cut) *
>
> #*********************************************************************
>
> 5.0 = etaj ! max rap for the jets{} = eta_min_pdg ! rap cut for other
> particles (use pdg code). Applied on particle and anti-particle
>
> {} = eta_max_pdg ! rap cut for other particles (syntax e.g. {6: 2.5, 23:
> 5})
>
> #*********************************************************************
>
> # Minimum and maximum DeltaR distance *
>
> #*********************************************************************
>
> 0.0 = drjj ! min distance between jets
>
> -1.0 = drjjmax ! max distance between jets
>
> #*********************************************************************
>
> # Minimum and maximum invariant mass for pairs *
>
> #*********************************************************************
>
> 0.0 = mmjj ! min invariant mass of a jet pair
>
> -1.0 = mmjjmax ! max invariant mass of a jet pair
>
> {} = mxx_min_pdg ! min invariant mass of a pair of particles X/X~ (e.g.
> {6:250})
>
> {'default': False} = mxx_only_part_antipart ! if True the invariant mass
> is applied only
>
> ! to pairs of particle/antiparticle and not to pairs
> of the same pdg codes.
>
> #*********************************************************************
>
> # Minimum and maximum invariant mass for all letpons *
>
> #*********************************************************************
>
> 0.0 = mmnl ! min invariant mass for all letpons (l+- and vl)
>
> -1.0 = mmnlmax ! max invariant mass for all letpons (l+- and vl)
>
> #*********************************************************************
>
> # Minimum and maximum pt for 4-momenta sum of leptons *
>
> #*********************************************************************
>
> #*********************************************************************
>
> # Inclusive cuts *
>
> #*********************************************************************
>
> 0.0 = xptj ! minimum pt for at least one jet
>
> #*********************************************************************
>
> # Control the pt's of the jets sorted by pt *
>
> #*********************************************************************
>
> 0.0 = ptj1min ! minimum pt for the leading jet in pt
>
> 0.0 = ptj2min ! minimum pt for the second jet in pt
>
> 0.0 = ptj3min ! minimum pt for the third jet in pt
>
> -1.0 = ptj1max ! maximum pt for the leading jet in pt
>
> -1.0 = ptj2max ! maximum pt for the second jet in pt
>
> -1.0 = ptj3max ! maximum pt for the third jet in pt
>
> 0 = cutuse ! reject event if fails any (0) / all (1) jet pt cuts
>
> #*********************************************************************
>
> # Control the Ht(k)=Sum of k leading jets *
>
> #*********************************************************************
>
> 0.0 = htjmin ! minimum jet HT=Sum(jet pt)
>
> -1.0 = htjmax ! maximum jet HT=Sum(jet pt)
>
> 0.0 = ihtmin !inclusive Ht for all partons (including b)
>
> -1.0 = ihtmax !inclusive Ht for all partons (including b)
>
> 0.0 = ht2min ! minimum Ht for the two leading jets
>
> 0.0 = ht3min ! minimum Ht for the three leading jets
>
> -1.0 = ht2max ! maximum Ht for the two leading jets
>
> -1.0 = ht3max ! maximum Ht for the three leading jets
>
> #*********************************************************************
>
> # WBF cuts *
>
> #*********************************************************************
>
> 0.0 = xetamin ! minimum rapidity for two jets in the WBF case
>
> 0.0 = deltaeta ! minimum rapidity for two jets in the WBF case
>
> #*********************************************************************
>
> # maximal pdg code for quark to be considered as a light jet *
>
> # (otherwise b cuts are applied) *
>
> #*********************************************************************
>
> 4 = maxjetflavor ! Maximum jet pdg code
>
> #*********************************************************************
>
> #
>
> #*********************************************************************
>
> #
>
> #*********************************************************************
>
> # Store info for systematics studies *
>
> # WARNING: Do not use for interference type of computation *
>
> #*********************************************************************
>
> True = use_syst ! Enable systematics studies
>
> #
>
> systematics = systematics_program ! none, systematics [python], SysCalc
> [depreceted, C++]
>
> ['--mur=0.5,1,2', '--muf=0.5,1,2', '--pdf=errorset', '--alps=0.5,1,2'] =
> systematics_arguments ! see:
> https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/Systematics#Systematicspythonmodule
>
> # Syscalc is deprecated but to see the associate options type'update
> syscalc'177,1 93%
>
>
> On Mon, Oct 12, 2020 at 4:01 PM Olivier Mattelaer <
> <email address hidden>> wrote:
>
>> Your question #693409 on MadGraph5_aMC@NLO changed:
>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>
>> Status: Open => Answered
>>
>> Olivier Mattelaer proposed the following answer:
>> Then I do not see the point to not include the zero jet multiplicity.
>>
>> If you want to discard such multiplicity, you need at minimum pt cut on at
>> least one jet
>> (ptj1min) and you need obviously that such cut should be much larger than
>> QCUT (and therefore much larger than xqcut)
>>
>> Your high dependency in the QCUT variation is likely related to that
>> choice of parameter/process.
>>
>> Cheers,
>>
>> Olivier
>>
>>> On 12 Oct 2020, at 09:45, ouseph cj <
>> <email address hidden>> wrote:
>>>
>>> Question #693409 on MadGraph5_aMC@NLO changed:
>>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>>
>>> Status: Answered => Open
>>>
>>> ouseph cj is still having a problem:
>>> Dear Oliver
>>> Thanks for your reply.
>>> I used the default values in the run card for the
>>> analysis,Ptj=20,Xqcut=30,mmjj=0.
>>>
>>> Best
>>> ouseph
>>>
>>>
>>> On Mon, Oct 12, 2020 at 3:01 PM Olivier Mattelaer <
>>> <email address hidden>> wrote:
>>>
>>>> Your question #693409 on MadGraph5_aMC@NLO changed:
>>>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>>>
>>>> Status: Open => Answered
>>>>
>>>> Olivier Mattelaer proposed the following answer:
>>>> Hi,
>>>>
>>>> You can not use "2454" since that one has serious double counting.
>>>>
>>>> For the other three, they are apriori all good/bad. You have to check
>>>> the DJR plot to see if the removal of the double counting is working
>> well
>>>> and then you can decide.
>>>> In top of that, such removal should be associated to an uncertainty
>> which
>>>> in your case seems very large.
>>>>
>>>> Note that you are in a difficult case since you have a jet in the lowest
>>>> multiplicity. Is there any reason for doing that? Did you double check
>>>> your cut (what is the value auto_ptj_mjj for example)?
>>>>
>>>> Cheers,
>>>>
>>>> Olivier
>>>>
>>>>
>>>>> On 12 Oct 2020, at 05:10, ouseph cj <
>>>> <email address hidden>> wrote:
>>>>>
>>>>> New question #693409 on MadGraph5_aMC@NLO:
>>>>> https://answers.launchpad.net/mg5amcnlo/+question/693409
>>>>>
>>>>> I am working on the given process
>>>>>
>>>>> generate p p > j vl vl~ @0
>>>>> add process p p > j j vl vl~ @1
>>>>> add process p p > j j j vl vl~ @2
>>>>>
>>>>> I got X-section as 2454 pb
>>>>> and merging cross section
>>>>> 947pb
>>>>> 568pb
>>>>> 400pb
>>>>>
>>>>> which X- Section that I need to use for the calculation of N =
>> X-Section
>>>> *Luminosity *acceptance *efficiency.
>>>>> and why?
>>>>>
>>>>> Best
>>>>> Melbin
>>>>>
>>>>> --
>>>>> 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/693409/+confirm?answer_id=0
>>>>
>>>> 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/693409
>>>>
>>>> You received this question notification because you asked the question.
>>>>
>>>
>>> --
>>> 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/693409/+confirm?answer_id=3
>>
>> 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/693409
>>
>> You received this question notification because you asked the question.
>>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Revision history for this message
ouseph cj (ouseph444) said :
#9

Thanks Olivier Mattelaer, that solved my question.