MPI Analysis using 4 jet events

Some helpful links

  • The current version of the analyzer code can be found in CVS, here.

References:

Analysis overview

The intention of this analysis is to make a measurement of the rate of secondary hard scatterings in a single nuclear interaction typically referred to as double parton scattering (DPS). Our study is modelled very closely on a similar study by the CDF collaboration published in 1993 (see links). Their approach can be summarised as utilising so called discriminator variable to characterise the differences in the topology of events involving 4 jets for the case that there is DPS and when there is only a single interaction. This is explained in more detail in the analysis notes, link to AN.

Standard selection cuts

  • number of primary vertices = 1
  • vertex |z| ≤ 20
  • vertex number of DOF ≥ 4
  • number of jets ≥ 4
  • |η| < 2.4
  • number of jet constituents > 1
  • number of charged constituents > 0
  • charged hadron fraction > 0
  • neutral fraction < 0.9
  • pT > 20 GeV
  • pT,1 + pT,2 > 75 GeV

Datasets

  • NOTE : There is a preselection applied while producing ntuples which requires that there be two jets with pT > 5 GeV in each event. The preselection also includes the selection of good lumi sections within the specified run range.

Dataset name Ninit (106) Npreselected (106) Nfinal/ Npreselected (Standard selection) Integrated luminosity (nb-1) Cross-section (nb)
Data        
/MinimumBias/Commissioning10-Sep17ReReco_v2/RECO (132440 - 135575) 572 19.4 0.021% 7.73 ---
/JetMETTau/Run2010A-Nov4ReReco_v1/RECO ( 136035 - 137028) 15.04 0.78 0.34% 5.09 ---
MC - Pythia8          
/QCD_Pt_15to30_Tune1_7TeV_pythia8/Fall10-START38_V12-v1/GEN-SIM-RECO 1.1 1.1 0.003% 1.41 780000
/QCD_Pt_30to50_Tune1_7TeV_pythia8/Fall10-START38_V12-v1/GEN-SIM-RECO 1.1 1.1 0.7% 21.87 50300
/QCD_Pt_50to80_Tune1_7TeV_pythia8/Fall10-START38_V12-v1/GEN-SIM-RECO 1.1 1.1 7.1% 180.8 6030
/QCD_Pt_80to120_Tune1_7TeV_pythia8/Fall10-START38_V12-v1/GEN-SIM-RECO 1.1 1.1 19% 1459 751
/QCD_Pt_120to170_Tune1_7TeV_pythia8/Fall10-START38_V12-v1/GEN-SIM-RECO 0.88 0.88 29% 7857 112
MC - Pythia6          
/QCD_Pt_15to30_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 5.45 5.44 0.002% 6.68 815900
/QCD_Pt_30to50_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 3.26 3.26 0.5% 61.37 53120
/QCD_Pt_50to80_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 3.19 3.19 4.9% 501.8 6360
/QCD_Pt_80to120_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 3.21 3.21 13% 4090.3 784.3
/QCD_Pt_120to170_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 3.05 3.05 21% 26499 115.1
Tune D6T          
/QCD_Pt_15to30_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 2.0       236000
/QCD_Pt_30to50_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 0.5       53110
/QCD_Pt_50to80_TuneZ2_7TeV_pythia6/Fall10-START38_V12-v1/GEN-SIM-RECO 0.5       7130

Trigger

Trigger name Bit position
HLT_L1_BscMinBiasOR_BptxPlusORMinus 1
HLT_L1Jet6U 2
HLT_L1Jet10U 3
HLT_Jet15U 4
HLT_Jet30U 5
HLT_Jet50U 6
HLT_Jet70U 7
HLT_Jet100U 8
HLT_FwdJet20U 9
HLT_Jet15U_HcalNoiseFiltered 10
HLT_BTagIP_Jet50U 11
HLT_DiJetAve15U 12
HLT_DiJetAve30U 13
HLT_DiJetAve50U 14
HLT_DoubleJet15U_ForwardBackward 15
HLT_QuadJet15U 16
HLT_HT100U 17
HLT_Mu9 18
HLT_Mu11 19
HLT_Mu13 20
HLT_Mu15 21
HLT_Ele10_LW_L1R 22
HLT_Ele15_SW_L1R 23
HLT_Ele15_SW_CaloEleId_L1R 24
HLT_Ele17_SW_CaloEleId_L1R 25
HLT_Ele15_SW_TightEleId_L1R 26

Since we utilize both MinBias and JetMET samples and compare these to QCD samples, we need to select on a trigger that will give us a QCD dominated data samples. The lowest threshold jet trigger available is HLT_Jet15U -- not prescaled at all for the selected range -- so we need to correct for any inefficiencies. To do this we considered turn-on curves for several kinematic distributions of the two leading jets in our selected events.

Jet1Pt_Trigger.png

Jet2Pt_Trigger.png

2jetHT_Trigger.png

4jetHT_Trigger.png

Our conclusion is to requrie the sum pT of the leading two jets be greater than 75 GeV.

Jet Energy Scale

Jet corrections are applied according to the prescribed methods on the jet correction twiki page. Things that need to be done here are:

  • Include residual corrections.

  • Include JEC uncertainties that are stored in the dataset. Propagate these to find the effect on our fits.

Generator level studies

  • Some simple overlays of pythia8 QCD with and without a DPS enrichment, here.

Data/MC comparisons

Standard selection

Using JetMETTau stream data with runNumber <= 137208 and selecting HLT_Jet15U, the yield is

Selection NEvents
Initial number of events: 801803
Pass HLT selection 754542
One and only one primary vertex: 552959
Vertex displacement in z < cm: 552746
Vertex ndof >= 4: 552415
abs(η) < 2.4 : 323067
Miscellaneous jet quality cuts: 313393
p_{T,1/2} > 20 GeV and p_{T,3/4} > 20: 3906
p_{T,1} + p_{T,2} > 75 GeV: 2644
Final number of events: 2644

The cuts are as described above. The most recent overlays with fit results are here .

Older comparisons are here and here.

Isolated dijet pair selection

We take an alternative approach which picks out events that are "signal"-like, i.e., they consist of two isolated dijet pairs. The isolation selection requires the pair consisting of the leading two jets (j1 and j2) be in the opposite side of the detector (w.r.t. eta) than the pair made up of the next two jets (j3 and j4). We then also require that the Δφ of the jets in each pair be greater than 2.0. Hence we have two isolated dijet pairs. This selection greatly reduces the number of selected events so we lower the pT threshold on j3 and j4 to 10 GeV. Results are here. This was expanded to include the effects of a scan on the minimum sum pT of the second pair. Results are here.

Old comparisons

Data Runs
/MinimumBias/Comissioning10-SD_JetMETTau-Jun14thSkim_v1/RECO 132440 - 135807
/JetMETTau/Run2010A-Jun14thReReco_v2/RECO 135808 - 137546
MC  
/QCD_Pt-15_7TeV-pythia8/Spring10-START3X_V26B-v2/GEN-SIM-RECO  
/QCD_Pt-20_TuneD6T_7TeV-pythia6/Summer10-START36_V10-v1/GEN-SIM-RECO  

Selection cut Data Pythia 8 Pythia 6 Signal
Initial number of events: 1286731 3866466 4650673  
Pass HLT selection 1222406 791134 1961961  
One and only one primary vertex: 1076132 751180 1893103  
Vertex displacement in z < 15 cm: 1075551 751180 1893102  
Vertex ndof >= 4: 1075407 751165 1893076  
abs(η) < 2.4: 749475 458647 1282702  
Miscellaneous jet quality cuts: 742030 455035 1272134  
p_{T} > 20 GeV: 11302 10227 30545  
p_{T,1} + p_{T,2} > 70 GeV: 8543 8026 20415  
5th jet pt < 15: 4624 3845 11123  

JMT on QCD

  • NOTE: The leading jet pT cut was raised to 35 GeV.

Data Runs
/MinimumBias/Comissioning10-SD_JetMETTau-Jun14thSkim_v1/RECO 132440 - 135807
/JetMETTau/Run2010A-Jun14thReReco_v2/RECO 135808 - 137546
MC  
/QCD_Pt-15_7TeV-pythia8/Spring10-START3X_V26B-v2/GEN-SIM-RECO  

Kinematic quantities

pT for four leading jets: jet 1, jet 2, jet 3, jet 4

Discriminator variables

MinBias on QCD

Data Runs
/MinimumBias/Commissioning10-Jun14thReReco_v1/RECO 132440 - 135807
/MinimumBias/Run2010A-Jun14thReReco_v2/RECO 135808 - 137546
MC  
/QCD_Pt-15_7TeV-pythia8/Spring10-START3X_V26B-v2/GEN-SIM-RECO N/A

Kinematic quantities

pT for four leading jets: jet 1, jet 2, jet 3, jet 4

Discriminator variables

Data/Data comparisons for leading jet pT > 20 GeV and pT > 35 GeV

Some kinematic quantities

pT for four leading jets: jet 1, jet 2, jet 3, jet 4

Discriminator variables

Comparison of MC with DPS on and off

Comparisons for various pT cuts from June 2010 are here.

Discriminator variables

  • SMin_SnoS_ratio.png

  • Smin_SnoS.png

  • Spt_SnoS_ratio.png

  • Spt_SnoS.png

  • deltaS_SnoS_ratio.png

  • deltaS_SnoS.png

Comparison of SpT' for MC generated with phase space pT,min = 50 GeV/c or 20 GeV/c.

  • Cuts applied are pT > 15 GeV and |η| < 2.5.

  • MC samples were generated using Pythia8 with the following options in the config file:

    PythiaParameters = cms.PSet(
        processParameters = cms.vstring('Main:timesAllowErrors    = 10000',
            'ParticleDecays:limitTau0 = on',
            'ParticleDecays:tau0Max   = 10.',
            'Beams:allowVertexSpread = on',
            'PhaseSpace:pTHatMin      = 50.',
            'HardQCD:all = on',
            'SecondHard:generate = on',
            'SecondHard:TwoJets = on'

Phase space p;T,min = 50 GeV:


 *-------  PYTHIA Process Initialization  --------------------------*
 |                                                                  |
 | We collide p+ with p+ at a CM energy of 7.000e+03 GeV            |
 |                                                                  |
 |------------------------------------------------------------------|
 |                                                    |             |
 | Subprocess                                    Code |   Estimated |
 |                                                    |    max (mb) |
 |                                                    |             |
 |------------------------------------------------------------------|
 |                                                    |             |
 | g g -> g g                                     111 |   2.241e-02 |
 | g g -> q qbar (uds)                            112 |   3.144e-04 |
 | q g -> q g                                     113 |   2.731e-02 |
 | q q(bar)' -> q q(bar)'                         114 |   3.688e-03 |
 | q qbar -> g g                                  115 |   2.894e-05 |
 | q qbar -> q' qbar' (uds)                       116 |   1.430e-05 |
 | g g -> c cbar                                  121 |   1.046e-04 |
 | q qbar -> c cbar                               122 |   4.761e-06 |
 | g g -> b bbar                                  123 |   1.027e-04 |
 | q qbar -> b bbar                               124 |   4.715e-06 |
 |                                                    |             |
 *-------  End PYTHIA Process Initialization -----------------------*

 *-------  PYTHIA Multiple Interactions Initialization  ------------* 
 |                                                                  | 
 |                   sigmaNonDiffractive =   48.45 mb               | 
 |                                                                  | 
 |    pT0 =  3.12 gives sigmaInteraction =  152.06 mb: accepted     | 
 |                                                                  | 
 *-------  End PYTHIA Multiple Interactions Initialization  --------* 
 PYTHIA Warning in MultipleInteractions::init: maximum increased by factor 1.539

 *-------  PYTHIA Flag + Mode + Parm + Word Settings (changes only)  ----------------------------------------------* 
 |                                                                                                                 | 
 | Name                                          |                      Now |      Default         Min         Max | 
 |                                               |                          |                                      | 
 | Beams:allowVertexSpread                       |                       on |          off                         | 
 | HardQCD:all                                   |                       on |          off                         | 
 | Main:timesAllowErrors                         |                    10000 |           10           0             | 
 | ParticleDecays:limitTau0                      |                       on |          off                         | 
 | PhaseSpace:pTHatMin                           |                 50.00000 |          0.0         0.0             | 
 | SecondHard:generate                           |                       on |          off                         | 
 | SecondHard:TwoJets                            |                       on |          off                         | 
 |                                                                                                                 | 
 *-------  End PYTHIA Flag + Mode + Parm + Word Settings  ---------------------------------------------------------* 
Begin processing the 1st record. Run 1, Event 1, LumiSection 1 at 19-May-2010 00:32:23 CDT
...

 *-------  PYTHIA Event and Cross Section Statistics  --------------------------------------------------------*
 |                                                                                                            |
 | Subprocess                               Code |            Number of events       |      sigma +- delta    |
 |                                               |       Tried   Selected   Accepted |     (estimated) (mb)   |
 |                                               |                                   |                        |
 |------------------------------------------------------------------------------------------------------------|
 |                                               |                                   |                        |
 | First hard process:                           |                                   |                        |
 |                                               |                                   |                        |
 | g g -> g g                                111 |         675         91         79 |   2.553e-07  2.860e-08 |
 | g g -> q qbar (uds)                       112 |           5          0          0 |   0.000e+00  0.000e+00 |
 | q g -> q g                                113 |         789         75         61 |   2.295e-07  2.762e-08 |
 | q q(bar)' -> q q(bar)'                    114 |         122         13         10 |   3.592e-08  7.921e-09 |
 | q qbar -> g g                             115 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> q' qbar' (uds)                  116 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> c cbar                             121 |           7          2          0 |   0.000e+00  0.000e+00 |
 | q qbar -> c cbar                          122 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> b bbar                             123 |           5          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> b bbar                          124 |           0          0          0 |   0.000e+00  0.000e+00 |
 |                                               |                                   |                        |
 | sum                                           |        1603        181        150 |   5.207e-07  5.362e-08 |
 |                                               |                                   |                        |
 |------------------------------------------------------------------------------------------------------------|
 |                                               |                                   |                        |
 | Second hard process:                          |                                   |                        |
 |                                               |                                   |                        |
 | g g -> g g                                111 |         667         74         60 |   2.327e-07  2.762e-08 |
 | g g -> q qbar (uds)                       112 |           8          2          1 |   2.542e-09  2.552e-09 |
 | q g -> q g                                113 |         806         84         72 |   2.317e-07  2.693e-08 |
 | q q(bar)' -> q q(bar)'                    114 |         112         18         15 |   4.645e-08  8.685e-09 |
 | q qbar -> g g                             115 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> q' qbar' (uds)                  116 |           1          1          1 |   8.626e-10  8.661e-10 |
 | g g -> c cbar                             121 |           3          2          1 |   2.000e-09  2.008e-09 |
 | q qbar -> c cbar                          122 |           1          0          0 |   0.000e+00  0.000e+00 |
 | g g -> b bbar                             123 |           2          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> b bbar                          124 |           0          0          0 |   0.000e+00  0.000e+00 |
 |                                               |                                   |                        |
 | sum                                           |        1600        181        150 |   5.162e-07  5.332e-08 |
 |                                               |                                   |                        |
 |------------------------------------------------------------------------------------------------------------|
 |                                                                                                            |
 | Uncombined cross sections for the two event sets were  6.412e-03 and 6.453e-03 mb, respectively, combined  |
 | using a sigma(nonDiffractive) of  4.845e+01 mb and an impact-parameter enhancement factor of  1.459e+00.   |
 |                                                                                                            |
 *-------  End PYTHIA Event and Cross Section Statistics -----------------------------------------------------*



 *-------  PYTHIA Process Initialization  --------------------------*
 |                                                                  |
 | We collide p+ with p+ at a CM energy of 7.000e+03 GeV            |
 |                                                                  |
 |------------------------------------------------------------------|
 |                                                    |             |
 | Subprocess                                    Code |   Estimated |
 |                                                    |    max (mb) |
 |                                                    |             |
 |------------------------------------------------------------------|
 |                                                    |             |
 | g g -> g g                                     111 |   2.241e-02 |
 | g g -> q qbar (uds)                            112 |   3.144e-04 |
 | q g -> q g                                     113 |   2.731e-02 |
 | q q(bar)' -> q q(bar)'                         114 |   3.688e-03 |
 | q qbar -> g g                                  115 |   2.894e-05 |
 | q qbar -> q' qbar' (uds)                       116 |   1.430e-05 |
 | g g -> c cbar                                  121 |   1.046e-04 |
 | q qbar -> c cbar                               122 |   4.761e-06 |
 | g g -> b bbar                                  123 |   1.027e-04 |
 | q qbar -> b bbar                               124 |   4.715e-06 |
 |                                                                  |
 *-------  End PYTHIA Process Initialization -----------------------*

 *-------  PYTHIA Multiple Interactions Initialization  ------------* 
 |                                                                  | 
 |                   sigmaNonDiffractive =   48.45 mb               | 
 |                                                                  | 
 |    pT0 =  3.12 gives sigmaInteraction =  151.76 mb: accepted     | 
 |                                                                  | 
 *-------  End PYTHIA Multiple Interactions Initialization  --------* 
 PYTHIA Warning in MultipleInteractions::init: maximum increased by factor 1.541

 *-------  PYTHIA Flag + Mode + Parm + Word Settings (changes only)  ----------------------------------------------* 
 |                                                                                                                 | 
 | Name                                          |                      Now |      Default         Min         Max | 
 |                                               |                          |                                      | 
 | Beams:allowVertexSpread                       |                       on |          off                         | 
 | HardQCD:all                                   |                       on |          off                         | 
 | Main:timesAllowErrors                         |                    10000 |           10           0             | 
 | ParticleDecays:limitTau0                      |                       on |          off                         | 
 | PhaseSpace:pTHatMin                           |                 50.00000 |          0.0         0.0             | 
 |                                                                                                                 | 
 *-------  End PYTHIA Flag + Mode + Parm + Word Settings  ---------------------------------------------------------* 
Begin processing the 1st record. Run 1, Event 1, LumiSection 1 at 19-May-2010 00:27:57 CDT
...

 *-------  PYTHIA Event and Cross Section Statistics  -------------------------------------------------------------*
 |                                                                                                                 |
 | Subprocess                                    Code |            Number of events       |      sigma +- delta    |
 |                                                    |       Tried   Selected   Accepted |     (estimated) (mb)   |
 |                                                    |                                   |                        |
 |-----------------------------------------------------------------------------------------------------------------|
 |                                                    |                                   |                        |
 | g g -> g g                                     111 |         577         64         64 |   2.956e-03  1.611e-04 |
 | g g -> q qbar (uds)                            112 |           3          1          1 |   9.544e-05  9.544e-05 |
 | q g -> q g                                     113 |         597         71         71 |   3.034e-03  2.016e-04 |
 | q q(bar)' -> q q(bar)'                         114 |          89         13         13 |   4.280e-04  7.041e-05 |
 | q qbar -> g g                                  115 |           1          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> q' qbar' (uds)                       116 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> c cbar                                  121 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> c cbar                               122 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> b bbar                                  123 |           3          1          1 |   1.671e-05  1.671e-05 |
 | q qbar -> b bbar                               124 |           0          0          0 |   0.000e+00  0.000e+00 |
 |                                                    |                                   |                        |
 | sum                                                |        1270        150        150 |   6.530e-03  2.846e-04 |
 |                                                                                                                 |
 *-------  End PYTHIA Event and Cross Section Statistics ----------------------------------------------------------*


SpT' with DPS turned off and on and the corresponding individual jet pT and sum pT (linear/log) distributions.

Phase space p;T,min = 20 GeV:


 *-------  PYTHIA Process Initialization  --------------------------*
 |                                                                  |
 | We collide p+ with p+ at a CM energy of 7.000e+03 GeV            |
 |                                                                  |
 |------------------------------------------------------------------|
 |                                                    |             |
 | Subprocess                                    Code |   Estimated |
 |                                                    |    max (mb) |
 |                                                    |             |
 |------------------------------------------------------------------|
 |                                                    |             |
 | g g -> g g                                     111 |   1.369e+00 |
 | g g -> q qbar (uds)                            112 |   1.461e-02 |
 | q g -> q g                                     113 |   8.726e-01 |
 | q q(bar)' -> q q(bar)'                         114 |   9.340e-02 |
 | q qbar -> g g                                  115 |   6.842e-04 |
 | q qbar -> q' qbar' (uds)                       116 |   3.085e-04 |
 | g g -> c cbar                                  121 |   4.812e-03 |
 | q qbar -> c cbar                               122 |   1.020e-04 |
 | g g -> b bbar                                  123 |   4.322e-03 |
 | q qbar -> b bbar                               124 |   9.671e-05 |
 |                                                    |             |
 *-------  End PYTHIA Process Initialization -----------------------*

 *-------  PYTHIA Multiple Interactions Initialization  ------------*
 |                                                                  |
 |                   sigmaNonDiffractive =   48.45 mb               |
 |                                                                  |
 |    pT0 =  3.12 gives sigmaInteraction =  152.06 mb: accepted     |
 |                                                                  |
 *-------  End PYTHIA Multiple Interactions Initialization  --------*
 PYTHIA Warning in MultipleInteractions::init: maximum increased by factor 1.539

 *-------  PYTHIA Flag + Mode + Parm + Word Settings (changes only)  ----------------------------------------------*
 |                                                                                                                 |
 | Name                                          |                      Now |      Default         Min         Max |
 |                                               |                          |                                      |
 | Beams:allowVertexSpread                       |                       on |          off                         |
 | HardQCD:all                                   |                       on |          off                         |
 | Main:timesAllowErrors                         |                    10000 |           10           0             |
 | ParticleDecays:limitTau0                      |                       on |          off                         |
 | PhaseSpace:pTHatMin                           |                 20.00000 |          0.0         0.0             |
 | SecondHard:generate                           |                       on |          off                         |
 | SecondHard:TwoJets                            |                       on |          off                         |
 |                                                                                                                 |
 *-------  End PYTHIA Flag + Mode + Parm + Word Settings  ---------------------------------------------------------*
Begin processing the 1st record. Run 1, Event 1, LumiSection 1 at 18-May-2010 19:25:05 CDT
...

 *-------  PYTHIA Event and Cross Section Statistics  --------------------------------------------------------*
 |                                                                                                            |
 | Subprocess                               Code |            Number of events       |      sigma +- delta    |
 |                                               |       Tried   Selected   Accepted |     (estimated) (mb)   |
 |                                               |                                   |                        |
 |------------------------------------------------------------------------------------------------------------|
 |                                               |                                   |                        |
 | First hard process:                           |                                   |                        |
 |                                               |                                   |                        |
 | g g -> g g                                111 |          88         16         16 |   1.339e-03  3.422e-04 |
 | g g -> q qbar (uds)                       112 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q g -> q g                                113 |          71          7          6 |   5.480e-04  1.862e-04 |
 | q q(bar)' -> q q(bar)'                    114 |          11          4          4 |   1.323e-04  5.239e-05 |
 | q qbar -> g g                             115 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> q' qbar' (uds)                  116 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> c cbar                             121 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> c cbar                          122 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> b bbar                             123 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> b bbar                          124 |           0          0          0 |   0.000e+00  0.000e+00 |
 |                                               |                                   |                        |
 | sum                                           |         170         27         26 |   2.019e-03  4.952e-04 |
 |                                               |                                   |                        |
 |------------------------------------------------------------------------------------------------------------|
 |                                               |                                   |                        |
 | Second hard process:                          |                                   |                        |
 |                                               |                                   |                        |
 | g g -> g g                                111 |          74         15         14 |   1.224e-03  3.345e-04 |
 | g g -> q qbar (uds)                       112 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q g -> q g                                113 |          54         10         10 |   6.589e-04  1.939e-04 |
 | q q(bar)' -> q q(bar)'                    114 |           5          1          1 |   1.247e-04  1.276e-04 |
 | q qbar -> g g                             115 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> q' qbar' (uds)                  116 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> c cbar                             121 |           1          1          1 |   1.527e-05  1.562e-05 |
 | q qbar -> c cbar                          122 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> b bbar                             123 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> b bbar                          124 |           0          0          0 |   0.000e+00  0.000e+00 |
 |                                               |                                   |                        |
 | sum                                           |         134         27         26 |   2.023e-03  5.147e-04 |
 |                                               |                                   |                        |
 |------------------------------------------------------------------------------------------------------------|
 |                                                                                                            |
 | Uncombined cross sections for the two event sets were  3.340e-01 and 3.448e-01 mb, respectively, combined  |
 | using a sigma(nonDiffractive) of  4.845e+01 mb and an impact-parameter enhancement factor of  1.776e+00.   |
 |                                                                                                            |
 *-------  End PYTHIA Event and Cross Section Statistics -----------------------------------------------------*



 *-------  PYTHIA Process Initialization  --------------------------*
 |                                                                  |
 | We collide p+ with p+ at a CM energy of 7.000e+03 GeV            |
 |                                                                  |
 |------------------------------------------------------------------|
 |                                                    |             |
 | Subprocess                                    Code |   Estimated |
 |                                                    |    max (mb) |
 |                                                    |             |
 |------------------------------------------------------------------|
 |                                                    |             |
 | g g -> g g                                     111 |   1.369e+00 |
 | g g -> q qbar (uds)                            112 |   1.461e-02 |
 | q g -> q g                                     113 |   8.726e-01 |
 | q q(bar)' -> q q(bar)'                         114 |   9.340e-02 |
 | q qbar -> g g                                  115 |   6.842e-04 |
 | q qbar -> q' qbar' (uds)                       116 |   3.085e-04 |
 | g g -> c cbar                                  121 |   4.812e-03 |
 | q qbar -> c cbar                               122 |   1.020e-04 |
 | g g -> b bbar                                  123 |   4.322e-03 |
 | q qbar -> b bbar                               124 |   9.671e-05 |
 |                                                                  |
 *-------  End PYTHIA Process Initialization -----------------------*

 *-------  PYTHIA Multiple Interactions Initialization  ------------*
 |                                                                  |
 |                   sigmaNonDiffractive =   48.45 mb               |
 |                                                                  |
 |    pT0 =  3.12 gives sigmaInteraction =  151.76 mb: accepted     |
 |                                                                  |
 *-------  End PYTHIA Multiple Interactions Initialization  --------*
 PYTHIA Warning in MultipleInteractions::init: maximum increased by factor 1.541

 *-------  PYTHIA Flag + Mode + Parm + Word Settings (changes only)  ----------------------------------------------*
 |                                                                                                                 |
 | Name                                          |                      Now |      Default         Min         Max |
 |                                               |                          |                                      |
 | Beams:allowVertexSpread                       |                       on |          off                         |
 | HardQCD:all                                   |                       on |          off                         |
 | Main:timesAllowErrors                         |                    10000 |           10           0             |
 | ParticleDecays:limitTau0                      |                       on |          off                         |
 | PhaseSpace:pTHatMin                           |                 20.00000 |          0.0         0.0             |
 |                                                                                                                 |
 *-------  End PYTHIA Flag + Mode + Parm + Word Settings  ---------------------------------------------------------*
Begin processing the 1st record. Run 1, Event 1, LumiSection 1 at 18-May-2010 19:29:02 CDT
...

 *-------  PYTHIA Event and Cross Section Statistics  -------------------------------------------------------------*
 |                                                                                                                 |
 | Subprocess                                    Code |            Number of events       |      sigma +- delta    |
 |                                                    |       Tried   Selected   Accepted |     (estimated) (mb)   |
 |                                                    |                                   |                        |
 |-----------------------------------------------------------------------------------------------------------------|
 |                                                    |                                   |                        |
 | g g -> g g                                     111 |         669         85         85 |   1.521e-01  8.924e-03 |
 | g g -> q qbar (uds)                            112 |           3          1          1 |   3.461e-03  3.461e-03 |
 | q g -> q g                                     113 |         419         58         58 |   1.054e-01  8.361e-03 |
 | q q(bar)' -> q q(bar)'                         114 |          43          6          6 |   7.901e-03  1.910e-03 |
 | q qbar -> g g                                  115 |           0          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> q' qbar' (uds)                       116 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> c cbar                                  121 |           1          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> c cbar                               122 |           0          0          0 |   0.000e+00  0.000e+00 |
 | g g -> b bbar                                  123 |           1          0          0 |   0.000e+00  0.000e+00 |
 | q qbar -> b bbar                               124 |           0          0          0 |   0.000e+00  0.000e+00 |
 |                                                    |                                   |                        |
 | sum                                                |        1136        150        150 |   2.689e-01  1.285e-02 |
 |                                                                                                                 |
 *-------  End PYTHIA Event and Cross Section Statistics ----------------------------------------------------------*


SpT' with DPS turned off and on and the corresponding individual jet pT and sum pT (linear/log) distributions.

-- NateOdell - 29-Apr-2010

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Topic revision: r75 - 2011-05-03 - unknown
 
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