The LHC Physics Environment

The LHC Physics Environment Talk : What We Have Learned at the Tevatron Rick Field University of Florida Outline of Talk The old days of Feynman-Field Phenomenology. Review what we learned about minbias, the underlying event, and event topologies in Run at CDF. Review the CDF Run 2 underlying event studies in high transverse momentum jet production and in Drell-Yan production. Describe the QCD Monte-Carlo models that are used to simulate hadronhadron collisions. Examine some extrapolations from the Tevatron to the LHC. CDF Run 2 CMS at the LHC University of Wisconsin, Madison June 24 th July 2 nd, 2009 Final-State Radiation PT(hard) UE&MB@CMS Rick Field Florida/CDF/CMS Page

Toward and Understanding of Hadron-Hadron Collisions Feynman-Field Phenomenology st hat! Feynman and Field From 7 GeV/c π 0 s to 600 GeV/c Jets. The early days of trying to understand and simulate hadronhadron collisions. PT(hard) Final-State Radiation Rick Field Florida/CDF/CMS Page 2

Hadron-Hadron Collisions FF 977 What happens when two hadrons collide at high energy? Most of the time the hadrons ooze through each other and fall apart (i.e. no hard scattering). The outgoing particles continue in roughly the same direction as initial proton and antiproton. Hadron??? Hadron Parton-Parton Scattering Soft Collision (no large transverse momentum) Occasionally there will be a large transverse momentum meson. Question: Where did it come from? Hadron Hadron We assumed it came from quark-quark elastic scattering, but we did not know how to calculate it! Black-Box Model high P T meson Rick Field Florida/CDF/CMS Page 3

Hadron-Hadron Collisions FF 977 What happens when two hadrons collide at high energy? Hadron Feynman quote from FF??? The model we shall choose is not a popular one, Most of the time the hadrons ooze so that we will not duplicate too much of the through each other and work fall apart of others (i.e. who are similarly analyzing no hard scattering). The various outgoing models (e.g. constituent interchange particles continue in roughly model, multiperipheral the same models, etc.). We shall Parton-Parton Scattering direction as initial proton assume and that the high P T particles arise from antiproton. direct hard collisions between constituent quarks in the incoming particles, which Occasionally there will fragment be a large or cascade down Hadron into several hadrons. transverse momentum meson. Question: Where did it come from? Hadron Soft Collision (no large transverse momentum) Hadron We assumed it came from quark-quark elastic scattering, but we did not know how to calculate it! Black-Box Model high P T meson Rick Field Florida/CDF/CMS Page 4

Quark Distribution Functions determined from deep-inelastic lepton-hadron collisions Quark-Quark Black-Box Box Model FF 977 No gluons! Quark-Quark Cross-Section Unknown! Deteremined from hadron-hadron collisions. Quark Fragmentation Functions determined from e + e - annihilations Rick Field Florida/CDF/CMS Page 5

Quark Distribution Functions determined from deep-inelastic lepton-hadron collisions Quark-Quark Black-Box Box Model FF 977 Feynman quote from FF Because of the incomplete knowledge of our functions some things can be predicted with more certainty than others. Those experimental results that are not well predicted can be used up to determine these functions in greater detail to permit better predictions of further experiments. Our papers will be a bit long because we wish to discuss this interplay in detail. No gluons! Quark-Quark Cross-Section Unknown! Deteremined from hadron-hadron collisions. Quark Fragmentation Functions determined from e + e - annihilations Rick Field Florida/CDF/CMS Page 6

Quark-Quark Black-Box Box Model Predict particle ratios FF 977 Predict increase with increasing CM energy W The underlying event (Beam-Beam Remnants)! Predict overall event topology (FFF paper 977) 7 GeV/c π 0 s! Rick Field Florida/CDF/CMS Page 7

Quark-Quark Black-Box Box Model Predict particle ratios FF 977 Predict increase with increasing CM energy W When Jim Cronin s group at the University of Chicago measured these rations and we knew we were on the right track! The underlying event (Beam-Beam Remnants)! Predict overall event topology (FFF paper 977) 7 GeV/c π 0 s! Rick Field Florida/CDF/CMS Page 8

QCD Approach: Quarks & Gluons Quark & Gluon Fragmentation Functions Q 2 dependence predicted from QCD FFF2 978 Parton Distribution Functions Q 2 dependence predicted from QCD Quark & Gluon Cross-Sections Calculated from QCD Rick Field Florida/CDF/CMS Page 9

QCD Approach: Quarks & Gluons Quark & Gluon Fragmentation Functions Q 2 dependence predicted from QCD FFF2 978 Parton Distribution Functions Q 2 dependence predicted from QCD Feynman quote from FFF2 We investigate whether the present experimental behavior of mesons with large transverse momentum in hadron-hadron collisions is consistent with the theory of quantum-chromodynamics (QCD) with asymptotic freedom, at least as the theory is now partially understood. Quark & Gluon Cross-Sections Calculated from QCD Rick Field Florida/CDF/CMS Page 0

High P T Jets Feynman, Field, & Fox (978) CDF (2006) Predict large jet cross-section 30 GeV/c! 600 GeV/c Jets! Feynman quote from FFF At the time of this writing, there is still no sharp quantitative test of QCD. An important test will come in connection with the phenomena of high P T discussed here. Rick Field Florida/CDF/CMS Page

QCD Monte-Carlo Models: High Transverse Momentum Jets Hard Scattering PT(hard) Hard Scattering Jet Jet PT(hard) Hard Scattering Component Final-State Radiation Jet Final-State Radiation Start with the perturbative 2-to-2 (or sometimes 2-to-3) parton-parton scattering and add initial and finalstate gluon radiation (in the leading log approximation or modified leading log approximation). The underlying event consists of the beam-beam remnants and from particles arising from soft or semi-soft multiple parton interactions (MPI). The underlying event is an unavoidable Of course the outgoing colored partons fragment into hadron jet and inevitably underlying event background to most collider observables observables receive contributions from initial and final-state radiation. and having good understand of it leads to more precise collider measurements! Rick Field Florida/CDF/CMS Page 2

QCD Monte-Carlo Models: Lepton-Pair Production High Lepton-Pair P T Z-Boson Production Anti-Lepton High PLepton-Pair T Z-Boson Production Jet Outgoing Anti-Lepton Parton Final-State Radiation Hard Scattering Component Final-State Radiation Z-boson Lepton Z-boson Lepton Start with the perturbative Drell-Yan muon pair production and add initial-state gluon radiation (in the leading log approximation or modified leading log approximation). The underlying event consists of the beam-beam remnants and from particles arising from soft or semi-soft multiple parton interactions (MPI). Of course the outgoing colored partons fragment into hadron jet and inevitably underlying event observables receive contributions from initial-state radiation. Rick Field Florida/CDF/CMS Page 3

Elastic Scattering - Collisions at the Tevatron Single Diffraction M The CDF Min-Bias trigger picks up most of the hard core cross-section plus a Double small Diffraction amount of single & double diffraction. M M 2 σ tot = σ EL + σ SD +σ DD +σ HC.8 TeV: 78mb = 8mb + 9mb + (4-7)mb + (47-44)mb The hard core component contains both hard and soft collisions. Inelastic Non-Diffractive Component Soft Hard Core (no hard scattering) Hard Core Beam-Beam Counters 3.2 < η < 5.9 Hard Hard Core (hard scattering) CDF Min-Bias trigger charged particle in forward BBC AND charged particle in backward BBC Final-State Radiation PT(hard) Initial-State Radiation Rick Field Florida/CDF/CMS Page 4

Particle Densities 2π η = 4π = 2.6 Charged Particles p T > 0.5 GeV/c η < CDF Run 2 Min-Bias CDF Run 2 Min-Bias Observable Average Average Density per unit η-φ φ 3 charged particles Nchg PTsum (GeV/c) Number of Charged Particles (p T > 0.5 GeV/c, η < ) Scalar p T sum of Charged Particles (p T > 0.5 GeV/c, η < ) 3.7 +/- 0.3 2.97 +/- 0.23 0.252 +/- 25 0.236 +/- 8 3 GeV/c PTsum dnchg/dηdφ = /4π 3/4π = 8 0.24 Divide by 4π 0 - η + dptsum/dηdφ = /4π 3/4π GeV/c = 8 0.24 GeV/c Study the charged particles (p T > 0.5 GeV/c, η < ) and form the charged particle density, dnchg/dηdφ, and the charged scalar p T sum density, dptsum/dηdφ. Rick Field Florida/CDF/CMS Page 5

CDF Run Min-Bias Data Charged Particle Density Charged Particle Pseudo-Rapidity Distribution: dn/dη Charged Particle Density: dn/dηdφ 7 6 CDF Published 0.8 CDF Published dn/dη 5 4 3 2 CDF Min-Bias.8 TeV CDF Min-Bias 630 GeV all PT 0-4 -3-2 - 0 2 3 4 Pseudo-Rapidity η dn/dηdφ 0.6 0.2 CDF Min-Bias 630 GeV CDF Min-Bias.8 TeV all PT -4-3 -2-0 2 3 4 Pseudo-Rapidity η <dn chg /dη> = 4.2 <dn chg /dηdφ> = 0.67 Shows CDF Min-Bias data on the number of charged particles per unit pseudo-rapidity at 630 and,800 GeV. There are about 4.2 charged particles per unit η in Min-Bias collisions at.8 TeV ( η <, all p T ). ηx = Convert to charged particle density, dn chg /dηdφ, by dividing by 2π. = There are about 0.67 charged particles per unit η-φ in Min-Bias 0.67 collisions at.8 TeV ( η <, all p T ). η = Rick Field Florida/CDF/CMS Page 6

CDF Run Min-Bias Data Charged Particle Density Charged Particle Pseudo-Rapidity Distribution: dn/dη Charged Particle Density: dn/dηdφ 7 6 CDF Published 0.8 CDF Published dn/dη 5 4 3 2 CDF Min-Bias.8 TeV CDF Min-Bias 630 GeV all PT 0-4 -3-2 - 0 2 3 4 Pseudo-Rapidity η dn/dηdφ 0.6 0.2 CDF Min-Bias 630 GeV CDF Min-Bias.8 TeV all PT -4-3 -2-0 2 3 4 Pseudo-Rapidity η <dn chg /dη> = 4.2 Shows CDF Min-Bias data on the number of charged particles per unit pseudo-rapidity at 630 and,800 GeV. There are about 4.2 charged particles per unit η in Min-Bias collisions at.8 TeV ( η <, all p T ). ηx = Convert to charged particle density, dn chg /dηdφ, by dividing by 2π. = There are about 0.67 charged particles per unit η-φ in Min-Bias 0.25 0.67 collisions at.8 TeV ( η <, all p T ). <dn chg /dηdφ> = 0.67 There are about 0.25 charged particles per unit η-φ in Min-Bias collisions at.96 TeV ( η <, p T > 0.5 GeV/c). η = Rick Field Florida/CDF/CMS Page 7

Highest p T charged particle! PTmax Direction Correlations in φ CDF Run Min-Bias Associated Charged Particle Density Charged Particle Density 0.5 0.3 0.2 0. CDF Preliminary data uncorrected Charged Particle Density: dn/dηdφ Charge Density Min-Bias PTmax 0 30 60 90 20 50 80 20 240 270 300 330 360 (degrees) Associated Density PTmax not included Associated densities do not include PTmax! Charged Particles ( η <, PT>0.5 GeV/c) Use the maximum p T charged particle in the event, PTmax, to define a direction and look at the the associated density, dnchg/dηdφ, in min-bias collisions (p T > 0.5 GeV/c, η < ). Shows the data on the dependence of the associated charged particle density, dnchg/dηdφ, for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) relative to PTmax (rotated to 80 o ) for min-bias events. Also shown is the average charged particle density, dnchg/dηdφ, for min-bias events. Rick Field Florida/CDF/CMS Page 8

Highest p T charged particle! PTmax Direction Correlations in φ CDF Run Min-Bias Associated Charged Particle Density Charged Particle Density 0.5 0.3 0.2 0. CDF Preliminary data uncorrected Charged Particle Density: dn/dηdφ Charge Density Min-Bias 0 30 60 90 20 50 80 20 240 270 300 330 360 (degrees) Use the maximum p T charged particle in the event, PTmax, to define a direction and look at the the associated It is more probable density, dnchg/dηdφ, to find a particle in min-bias collisions (p T > 0.5 GeV/c, η < ). accompanying PTmax than it is to find a particle in the central region! Shows the data on the dependence of the associated charged particle density, dnchg/dηdφ, for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) relative to PTmax (rotated to 80 o ) for min-bias events. Also shown is the average charged particle density, dnchg/dηdφ, for min-bias events. PTmax Associated Density PTmax not included Associated densities do not include PTmax! Charged Particles ( η <, PT>0.5 GeV/c) Rick Field Florida/CDF/CMS Page 9

CDF Run Min-Bias Associated Charged Particle Density Rapid rise in the particle density in the transverse region as PTmax increases! PTmax Direction Jet # Correlations in φ Jet #2 Ave Min-Bias 0.25 per unit η-φ Associated Particle Density 0.8 0.6 0.2 PTmax > 2.0 GeV/c PTmax > GeV/c PTmax > 0.5 GeV/c Associated Particle Density: dn/dηdφ Transverse Region PTmax not included Charged Particles ( η <, PT>0.5 GeV/c) PTmax 0 30 60 90 20 50 80 20 240 270 300 330 360 (degrees) CDF Preliminary data uncorrected Transverse Region Min-Bias PTmax > 2.0 GeV/c PTmax > 0.5 GeV/c Shows the data on the dependence of the associated charged particle density, dnchg/dηdφ, for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) relative to PTmax (rotated to 80 o ) for min-bias events with PTmax > 0.5,, and 2.0 GeV/c. Shows jet structure in min-bias collisions (i.e. the birth of the leading two jets!). Rick Field Florida/CDF/CMS Page 20

Charged Particle Density 0. Associated Charged Particle Density: dn/dηdφ RDF Preliminary py Tune A generator level PTmax > 5.0 GeV/c Min-Bias.96 TeV Region PTmax > GeV/c 0 30 60 90 20 50 80 20 240 270 300 330 360 (degrees) Min-Bias Associated Charged Particle Density PTmax > GeV/c PTmax > 2.0 GeV/c PTmax > 0.5 GeV/c Charged Particle Density.6.2 0.8 PTmax Direction Associated Charged Particle Density: dn/dηdφ RDF Preliminary Min-Bias py Tune A generator level.96 TeV "Toward" "Away" 0 2 4 6 8 0 2 4 6 8 20 PTmax (GeV/c) "Transverse" Shows the dependence of the associated charged particle density, dnchg/dηdφ, for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) relative to PTmax (rotated to 80 o ) for min-bias events at.96 TeV with PTmax > 0.5,, 2.0, 5.0, and GeV/c from PYTHIA Tune A (generator level). PTmax Direction Shows the associated charged particle density in the toward, away and transverse regions as a function of PTmax for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) for min-bias events at.96 TeV from PYTHIA Tune A (generator level). Rick Field Florida/CDF/CMS Page 2

Charged Particle Density 0. Associated Charged Particle Density: dn/dηdφ RDF Preliminary py Tune A generator level PTmax > 5.0 GeV/c Min-Bias.96 TeV Region PTmax > GeV/c 0 30 60 90 20 50 80 20 240 270 300 330 360 (degrees) Min-Bias Associated Charged Particle Density PTmax > GeV/c PTmax > 2.0 GeV/c PTmax > 0.5 GeV/c Charged Particle Density 2.5.6 2.0.2.5 0.8 0.5 PTmax Direction Associated Charged Particle Density: dn/dηdφ RDF RDF Preliminary Min-Bias Preliminary Min-Bias 4 TeV.96 TeV py Tune A generator level py Tune generator level "Toward" "Toward" "Away" Charged Charged Particles Particles ( η <, ( η <, PT>0.5 PT>0.5 GeV/c) GeV/c) 0 2 54 6 0 8 0 5 2 4 20 6 8 25 20 PTmax (GeV/c) "Away" "Transverse" "Transverse" Shows the dependence of the associated charged particle density, dnchg/dηdφ, for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) relative to PTmax (rotated to 80 o ) for min-bias events at.96 TeV with PTmax > 0.5,, 2.0, 5.0, and GeV/c from PYTHIA Tune A (generator level). PTmax Direction Shows the associated charged particle density in the toward, away and transverse regions as a function of PTmax for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) for min-bias events at.96 TeV from PYTHIA Tune A (generator level). Rick Field Florida/CDF/CMS Page 22

Charged Particle Density 0. Associated Charged Particle Density: dn/dηdφ RDF Preliminary py Tune A generator level PTmax > 5.0 GeV/c Min-Bias.96 TeV Region PTmax > GeV/c 0 30 60 90 20 50 80 20 240 270 300 330 360 (degrees) Min-Bias Associated Charged Particle Density PTmax > GeV/c PTmax > 2.0 GeV/c PTmax > 0.5 GeV/c "Transverse" Charged Particle Charged Density 2.5.2.6 2.0.2 0.8.5 0.6 0.8 PTmax Direction "Transverse" Associated Charged Particle Density: dn/dηdφ RDF Preliminary Min-Bias RDF Preliminary Min-Bias Min-Bias 4 TeV 4 TeV.96 TeV py Tune A generator level py Tune A generator level "Toward" "Toward" ~ factor of 2! "Away" "Transverse" 0.5 0.2 Charged Charged Particles Particles ( η <, ( η <, PT>0.5 PT>0.5 GeV/c) GeV/c) 0 2 54 6 0 8 0 5 2 4 20 6 8 25 20 PTmax (GeV/c) "Away".96 TeV "Transverse" Shows the dependence of the associated charged particle density, dnchg/dηdφ, for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) relative to PTmax (rotated to 80 o ) for min-bias events at.96 TeV with PTmax > 0.5,, 2.0, 5.0, and GeV/c from PYTHIA Tune A (generator level). PTmax Direction Shows the associated charged particle density in the toward, away and transverse regions as a function of PTmax for charged particles (p T > 0.5 GeV/c, η <, not including PTmax) for min-bias events at.96 TeV from PYTHIA Tune A (generator level). Rick Field Florida/CDF/CMS Page 23

Charged Density PTmax Direction ChgJet# Direction "Transverse" Charged Density 0.8 0.6 0.2 "Transverse" Charged Particle Density: dn/dηdφ RDF Preliminary py Tune A generator level PTmax ChgJet# Jet#.96 TeV 0.6 Jet# Direction 0 5 0 5 20 25 30 PT(jet#) or PT(chgjet#) or PTmax (GeV/c) Shows the charged particle density in the transverse region for charged particles (p T > 0.5 GeV/c, η < ) at.96 TeV as defined by PTmax, PT(chgjet#), and PT(jet#) from PYTHIA Tune A at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 24

CDF Run : Evolution of Charged Jets region very sensitive to the underlying event! Charged Jet # Direction Toward-Side Jet Charged Particle Correlations P T > 0.5 GeV/c η < CDF Run Analysis Charged Jet # Direction 2π Away Region Transverse Region Look at the charged particle density in the transverse region! φ Leading Jet Toward Region Transverse Region Away-Side Jet 0 Away Region - η + Look at charged particle correlations in the azimuthal angle relative to the leading charged particle jet. Define < 60 o as, 60 o < < 20 o as, and > 20 o as. All three regions have the same size in η-φ space, ηx = 2x20 o = 4π/3. Rick Field Florida/CDF/CMS Page 25

Run Charged Particle Density p T Distribution "Transverse" Charged Density "Transverse" Charged Particle Density: dn/dηdφ 0 CDF Run 0.75 0.50 0.25 0 data uncorrected CDF Min-Bias CDF JET20 Factor of 2!.8 TeV η < PT>0.5 GeV/c 0 5 0 5 20 25 30 35 40 45 50 PT(charged jet#) (GeV/c) Charged Particle Jet # Direction Min-Bias Compares the average transverse charge particle density with the average Min-Bias charge particle density ( η <, p T >0.5 GeV). Shows how the transverse charge particle density and the Min-Bias charge particle density is distributed in p T. Rick Field Florida/CDF/CMS Page 26

Run Charged Particle Density p T Distribution "Transverse" Charged Density Min-Bias 0 0.75 0.50 0.25 0 "Transverse" Charged Particle Density: dn/dηdφ CDF Run data uncorrected P T (charged jet#) > 30 GeV/c <dn chg /dηdφ> = 0.56 CDF Run Min-Bias data <dn chg /dηdφ> = 0.25 Factor of 2! 0 5 0 5 20 25 30 35 40 45 50 PT(charged jet#) (GeV/c) CDF Min-Bias CDF JET20.8 TeV η < PT>0.5 GeV/c Charged Density dn/dηdφdpt (/GeV/c) E+00 E-0 E-02 E-03 E-04 E-05 E-06 Min-Bias Charged Particle Density.8 TeV η < PT>0.5 GeV/c "Transverse" PT(chgjet#) > 5 GeV/c 0 2 4 6 8 0 2 4 PT(charged) (GeV/c) CDF Run data uncorrected "Transverse" PT(chgjet#) > 30 GeV/c Compares the average transverse charge particle density with the average Min-Bias charge particle density ( η <, p T >0.5 GeV). Shows how the transverse charge particle density and the Min-Bias charge particle density is distributed in p T. Rick Field Florida/CDF/CMS Page 27

Charged Jet # Direction Beam-Beam Remnants "Transverse" Charged Density 0 0.75 0.50 0.25 0 ISAJET 7.32 Density ISAJET uses a naïve leading-log parton shower-model which does not agree with the data! "Transverse" Charged Particle Density: dn/dηdφ CDF Run Data data uncorrected theory corrected "Remnants" Isajet 0 5 0 5 20 25 30 35 40 45 50 PT(charged jet#) (GeV/c) "Hard".8 TeV η < PT>0.5 GeV ISAJET Hard Component Plot shows average transverse charge particle density ( η <, p T >0.5 GeV) versus P T (charged jet#) compared to the QCD hard scattering predictions of ISAJET 7.32 (default parameters with P T (hard)>3 GeV/c). The predictions of ISAJET are divided into two categories: charged particles that arise from the break-up of the beam and target (beam-beam remnants); and charged particles that arise from the outgoing jet plus initial and final-state radiation (hard scattering component). Rick Field Florida/CDF/CMS Page 28

Charged Jet # Direction Beam-Beam Remnants "Transverse" Charged Density HERWIG uses a modified leadinglog parton shower-model which does agrees better with the data! "Transverse" Charged Particle Density: dn/dηdφ 0 0.75 0.50 0.25 0 HERWIG 6.4 Density CDF Run Data data uncorrected theory corrected Total "Remnants" "Hard" 0 5 0 5 20 25 30 35 40 45 50 PT(charged jet#) (GeV/c) Herwig 6.4 CTEQ5L PT(hard) > 3 GeV/c.8 TeV η < PT>0.5 GeV HERWIG Hard Component Plot shows average transverse charge particle density ( η <, p T >0.5 GeV) versus P T (charged jet#) compared to the QCD hard scattering predictions of HERWIG 5.9 (default parameters with P T (hard)>3 GeV/c). The predictions of HERWIG are divided into two categories: charged particles that arise from the break-up of the beam and target (beam-beam remnants); and charged particles that arise from the outgoing jet plus initial and final-state radiation (hard scattering component). Rick Field Florida/CDF/CMS Page 29

HERWIG 6.4 P T Distribution "Transverse" Charged Density 0 0.75 0.50 0.25 0 "Transverse" Charged Particle Density: dn/dηdφ CDF Data data uncorrected theory corrected HERWIG has the too steep of a p T dependence of the beam-beam remnant component of the underlying event! Total "Remnants" "Hard" 0 5 0 5 20 25 30 35 40 45 50 PT(charged jet#) (GeV/c) Herwig 6.4 CTEQ5L PT(hard) > 3 GeV/c.8 TeV η < PT>0.5 GeV Herwig P T (chgjet#) > 30 GeV/c <dn chg /dηdφ> = 0.5 Charged Density dn/dηdφdpt (/GeV/c) E+00 E-0 E-02 E-03 E-04 E-05 "Transverse" Charged Particle Density PT(chgjet#) > 5 GeV/c Herwig 6.4 CTEQ5L CDF Data data uncorrected theory corrected.8 TeV η < PT>0.5 GeV/c PT(chgjet#) > 30 GeV/c Herwig P T (chgjet#) > 5 GeV/c <dn chg /dηdφ> = 0 E-06 0 2 4 6 8 0 2 4 PT(charged) (GeV/c) Compares the average transverse charge particle density ( η <, p T >0.5 GeV) versus P T (charged jet#) and the p T distribution of the transverse density, dn chg /dηdφdp T with the QCD hard scattering predictions of HERWIG 6.4 (default parameters with P T (hard)>3 GeV/c. Shows how the transverse charge particle density is distributed in p T. Rick Field Florida/CDF/CMS Page 30

Multiple Hard Parton Collision Interaction initial-state radiation outgoing parton outgoing parton MPI: Multiple Parton Interactions final-state radiation initial-state radiation Hard Component outgoing jet PYTHIA models the soft component of the underlying event with color string fragmentation, but in addition includes a contribution arising from multiple parton interactions (MPI) in which one interaction is hard and the other is semi-hard. color string color string The probability that a hard scattering events also contains a semi-hard multiple parton interaction can be varied but adjusting the cut-off for the MPI. One can also adjust whether the probability of a MPI depends on the P T of the hard scattering, P T (hard) (constant cross section or varying with impact parameter). One can adjust the color connections and flavor of the MPI (singlet or nearest neighbor, q-qbar or glue-glue). Also, one can adjust how the probability of a MPI depends on P T (hard) (single or double Gaussian matter distribution). + final-state radiation Semi-Hard MPI or Beam-Beam Remnants Soft Component Rick Field Florida/CDF/CMS Page 3

MPI, Pile-Up, and Overlap MPI: Multiple Parton Interactions PT(hard) MPI: Additional 2-to-2 parton-parton scatterings within a single protonantiproton collision. Final-State Radiation Pile-Up Pile-Up Interaction Region z Primary Pile-Up: More than one proton-antiproton collision in the beam crossing. Overlap Overlap: An experimental timing issue where a proton-antiproton collision from the next beam crossing gets included in the protonantiproton collision from the current beam crossing because the next crossing happened before the event could be read out. Rick Field Florida/CDF/CMS Page 32

Parameter Default Tuning PYTHIA: Multiple Parton Interaction Parameters Description PARP(83) PARP(84) PARP(85) 0.5 0.2 0.33 Double-Gaussian: Fraction of total hadronic matter within PARP(84) Double-Gaussian: Fraction of the overall hadron radius containing the fraction PARP(83) of the total hadronic matter. Determines the energy Probability that the MPI produces two gluons dependence of the MPI! with color connections to the nearest neighbors. Hard Core Color String Multiple Parton Interaction Color String PARP(86) 0.66 Probability that Affects the MPI the produces amount two of gluons either as described initial-state by PARP(85) radiation! or as a closed gluon loop. The remaining fraction consists of quark-antiquark pairs. Multiple Parton Determine Interaction by comparing with 630 GeV data! Color String PARP(89) PARP(82) PARP(90) TeV.9 GeV/c 0.6 Determines the reference energy E 0. The cut-off P T0 that regulates the 2-to-2 scattering divergence /PT 4 /(PT 2 +P T0 2 ) 2 Determines the energy dependence of the cut-off P T0 as follows P T0 (E cm ) = P T0 (E cm /E 0 ) ε with ε = PARP(90) PT0 (GeV/c) 5 4 3 2 PYTHIA 6.206 Hard-Scattering Cut-Off PT0 Take E 0 =.8 TeV ε = 0.25 (Set A)) PARP(67) A scale factor that determines the maximum parton virtuality for space-like showers. The larger the value of PARP(67) the more initialstate radiation. ε = 0.6 (default) 00,000 0,000 00,000 Reference point at.8 TeV CM Energy W (GeV) Rick Field Florida/CDF/CMS Page 33

Parameter PARP(83) PARP(84) PARP(85) PARP(86) PARP(89) PARP(82) PARP(90) PARP(67) Default 0.5 0.2 0.33 0.66 TeV.9 GeV/c 0.6 Tuning PYTHIA: Multiple Parton Interaction Parameters Description Double-Gaussian: Fraction of total hadronic matter within PARP(84) Double-Gaussian: Fraction of the overall hadron radius containing the fraction PARP(83) of the total hadronic matter. Determines the energy Probability that the MPI produces two gluons dependence of the MPI! with color connections to the nearest neighbors. Probability that Affects the MPI the produces amount two of gluons either as described initial-state by PARP(85) radiation! or as a closed gluon loop. The remaining fraction consists of quark-antiquark pairs. Determines the reference energy E 0. The cut-off P T0 that regulates the 2-to-2 scattering divergence /PT 4 /(PT 2 +P T0 2 ) 2 Determines the energy dependence of the cut-off P T0 as follows P T0 (E cm ) = P T0 (E cm /E 0 ) ε with ε = PARP(90) A scale factor that determines the maximum parton virtuality for space-like showers. The larger the value of PARP(67) the more initialstate radiation. Hard Core PT0 (GeV/c) 5 4 3 2 Color String I will talk more about the energy dependence of MPI tomorrow morning! Multiple Parton Interaction Color String Multiple Parton Determine Interaction by comparing with 630 GeV data! PYTHIA 6.206 Color String Hard-Scattering Cut-Off PT0 Take E 0 =.8 TeV ε = 0.25 (Set A)) ε = 0.6 (default) 00,000 0,000 00,000 Reference point at.8 TeV CM Energy W (GeV) Rick Field Florida/CDF/CMS Page 34

PYTHIA default parameters Parameter MSTP(8) MSTP(82) PARP(8) PARP(82) PARP(89) PARP(90) PARP(67) 6.5.4.55 4.0 PYTHIA 6.206 Defaults MPI constant probability 6.25.9 2.,000 0.6 4.0 6.58.9 2.,000 0.6 6.206.9.9,000 0.6 "Transverse" Charged Density scattering 0 0.75 0.50 0.25 0 "Transverse" Charged Particle Density: dn/dηdφ CDF Data data uncorrected theory corrected Pythia 6.206 (default) MSTP(82)= PARP(8) =.9 GeV/c 0 5 0 5 20 25 30 35 40 45 50 PT(charged jet#) (GeV/c).8 TeV η < PT>0.5 GeV CTEQ3L CTEQ4L CTEQ5L CDF Min-Bias CDF JET20 Plot shows the charged particle density versus P T (chgjet#) compared to the QCD hard scattering predictions of PYTHIA 6.206 (P T (hard) > 0) using the default parameters for multiple parton interactions and CTEQ3L, CTEQ4L, and CTEQ5L. Note Change PARP(67) = 4.0 (< 6.38) PARP(67) = (> 6.38) Default parameters give very poor description of the underlying event! Rick Field Florida/CDF/CMS Page 35

Parameter MSTP(8) MSTP(82) PARP(82) PARP(83) PARP(84) PARP(85) PARP(86) PARP(89) PARP(90) PARP(67) Not the default! PYTHIA 6.206 CTEQ5L Tune B 0.5.8 TeV 0.25 New PYTHIA default (less initial-state radiation) 4.9 GeV Run PYTHIA Tune A Tune A 4 2.0 GeV 0.5 0.9 0.95.8 TeV 0.25 4.0 "Transverse" Charged Density CDF Default! "Transverse" Charged Particle Density: dn/dηdφ 0 0.75 0.50 0.25 0 CDF Preliminary data uncorrected theory corrected CTEQ5L Plot shows the transverse charged particle density versus P T (chgjet#) compared to the QCD hard scattering predictions of two tuned versions of PYTHIA 6.206 (CTEQ5L, Set B (PARP(67)=) and Set A (PARP(67)=4)). Old PYTHIA default (more initial-state radiation) PYTHIA 6.206 (Set B) PARP(67)= PYTHIA 6.206 (Set A) PARP(67)=4 0 5 0 5 20 25 30 35 40 45 50 PT(charged jet#) (GeV/c) Run Analysis.8 TeV η < PT>0.5 GeV Rick Field Florida/CDF/CMS Page 36

dn/dηdφ 0.8 0.6 0.2 CDF Published Charged Particle Density: dn/dηdφ Pythia 6.206 Set A CDF Min-Bias.8 TeV -4-3 -2-0 2 3 4 Pseudo-Rapidity η PYTHIA Tune A Min-Bias Soft + Hard.8 TeV all PT PYTHIA regulates the perturbative 2-to-2 parton-parton cross sections with cut-off parameters which allows one to run with Lots of hard scattering in P T Min-Bias (hard) > at 0. the One Tevatron! can simulate both hard and soft collisions in one program. PYTHIA Tune A CDF Run 2 Default Charged Particle Density The relative amount of hard versus soft depends on the cut-off and can be tuned. Charged Density dn/dηdφdpt (/GeV/c) E+00 E-0 E-02 E-03 E-04 E-05 E-06 CDF Preliminary PT(hard) > 0 GeV/c 0 2 4 6 8 0 2 4 PT(charged) (GeV/c) Tuned to fit the CDF Run underlying event! Pythia 6.206 Set A CDF Min-Bias Data.8 TeV η < 2% of Min-Bias events have P T (hard) > 5 GeV/c! % of Min-Bias events have P T (hard) > 0 GeV/c! This PYTHIA fit predicts that 2% of all Min-Bias events are a result of a hard 2-to-2 parton-parton scattering with P T (hard) > 5 GeV/c (% with P T (hard) > 0 GeV/c)! Rick Field Florida/CDF/CMS Page 37

PYTHIA Tune A LHC Min-Bias Predictions Charged Density dn/dηdφdpt (/GeV/c) E+00 E-0 E-02 E-03 E-04 E-05 Charged Particle Density Pythia 6.206 Set A.8 TeV 630 GeV 50% 2% of Min-Bias events have P T (hard) > 0 GeV/c! η < % of Events 40% PT(hard) > 5 GeV/c PT(hard) > 0 GeV/c 30% 20% Hard-Scattering in Min-Bias Events Pythia 6.206 Set A 4 TeV 0% 0% 00,000 0,000 00,000 CM Energy W (GeV) LHC? E-06 CDF Data 0 2 4 6 8 0 2 4 % of Min-Bias events have P T (hard) > 0 GeV/c! PT(charged) (GeV/c) Shows the center-of-mass energy dependence of the charged particle density, dn chg /dηdφdp T, for Min-Bias collisions compared with PYTHIA Tune A with P T (hard) > 0. PYTHIA Tune A predicts that % of all Min-Bias events at.8 TeV are a result of a hard 2-to-2 parton-parton scattering with P T (hard) > 0 GeV/c which increases to 2% at 4 TeV! Rick Field Florida/CDF/CMS Page 38

region is very sensitive to the underlying event! Towards, Away Jet # Direction Toward-Side Jet Away, Correlations relative to the leading jet Charged particles p T > 0.5 GeV/c η < Calorimeter towers E T > 0. GeV η < Z-Boson Jet # Direction 2π Look at the charged particle density, the charged PTsum density and the ETsum density in all 3 regions! Away Region Transverse Region φ Leading Jet Away-Side Jet Toward Region Transverse Region Away Region 0 - η + Look at correlations in the azimuthal angle relative to the leading charged particle jet ( η < ) or the leading calorimeter jet ( η < 2). Define < 60 o as, 60 o < < 20 o as Transverse, and > 20 o as. Each of the three regions have area η = 2 20 o = 4π/3. Rick Field Florida/CDF/CMS Page 39

Event Topologies Leading Jet events correspond to the leading calorimeter jet (MidPoint R = 0.7) in the region η < 2 with no other conditions. Inclusive 2-Jet Back-to-Back events are selected to have at least two jets with Jet# and Jet#2 nearly backto-back ( 2 > 50 o ) with almost equal transverse energies (P T (jet#2)/p T (jet#) > 0.8) with no other conditions. Exclusive 2-Jet Back-to-Back events are selected to have at least two jets with Jet# and Jet#2 nearly backto-back ( 2 > 50 o ) with almost equal transverse energies (P T (jet#2)/p T (jet#) > 0.8) and P T (jet#3) < 5 GeV/c. Leading ChgJet events correspond to the leading charged particle jet (R = 0.7) in the region η < with no other conditions. Z-Boson events are Drell-Yan events with 70 < M(lepton-pair) < 0 GeV with no other conditions. Jet # Direction Jet # Direction Jet #2 Direction ChgJet # Direction Z-Boson Direction Leading Jet subset Inc2J Back-to-Back subset Exc2J Back-to-Back Charged Jet Z-Boson Rick Field Florida/CDF/CMS Page 40

transmax & transmin Z-Boson Jet # Direction Direction Area = 4π/6 Jet # Direction Toward-Side Jet transmin very sensitive to the beam-beam remnants! TransMAX TransMIN TransMAX TransMIN Jet #3 Away-Side Jet Define the MAX and MIN transverse regions ( transmax and transmin ) on an event-by-event basis with MAX (MIN) having the largest (smallest) density. Each of the two transverse regions have an area in η-φ space of 4π/6. The transmin region is very sensitive to the beam-beam remnant and the soft multiple parton interaction components of the underlying event. The difference, transdif ( transmax minus transmin ), is very sensitive to the hard scattering component of the underlying event (i.e. hard initial and final-state radiation). The overall transverse density is the average of the transmax and transmin densities. Rick Field Florida/CDF/CMS Page 4

Observables at the Particle and Detector Level Leading Jet Observable Particle Level Detector Level Jet # Direction dnchg/dηdφ Number of charged particles per unit η-φ (p T > 0.5 GeV/c, η < ) Number of good charged tracks per unit η-φ (p T > 0.5 GeV/c, η < ) dptsum/dηdφ Scalar p T sum of charged particles per unit η-φ (p T > 0.5 GeV/c, η < ) Scalar p T sum of good charged tracks per unit η-φ (p T > 0.5 GeV/c, η < ) <p T > Average p T of charged particles (p T > 0.5 GeV/c, η < ) Average p T of good charged tracks (p T > 0.5 GeV/c, η < ) Jet # Direction Jet #2 Direction PTmax detsum/dηdφ PTsum/ETsum Maximum p T charged particle (p T > 0.5 GeV/c, η < ) Require Nchg Scalar E T sum of all particles per unit η-φ (all p T, η < ) Scalar p T sum of charged particles (p T > 0.5 GeV/c, η < ) divided by the scalar E T sum of all particles (all p T, η < ) Maximum p T good charged tracks (p T > 0.5 GeV/c, η < ) Require Nchg Scalar E T sum of all calorimeter towers per unit η-φ (E T > 0. GeV, η < ) Scalar p T sum of good charged tracks (p T > 0.5 GeV/c, η < ) divided by the scalar E T sum of calorimeter towers (E T > 0. GeV, η < ) Back-to-Back Rick Field Florida/CDF/CMS Page 42

UE Parameters ISR Parameters Intrensic KT CDF Run P (Z) T PYTHIA 6.2 CTEQ5L Parameter MSTP(8) MSTP(82) PARP(82) PARP(83) PARP(84) PARP(85) PARP(86) PARP(89) PARP(90) PARP(62) PARP(64) PARP(67) MSTP(9) PARP(9) PARP(93) Tune A 4 2.0 GeV 0.5 0.9 0.95.8 TeV 0.25 4.0 5.0 Tune AW 4 2.0 GeV 0.5 0.9 0.95.8 TeV 0.25.25 0.2 4.0 2. 5.0 Tune used by the CDF-EWK group! PT Distribution /N dn/dpt 0.2 8 4 0 Z-Boson Transverse Momentum CDF Run Data PYTHIA Tune A PYTHIA Tune AW 0 2 4 6 8 0 2 4 6 8 20 Z-Boson PT (GeV/c) CDF Run published.8 TeV Normalized to Shows the Run Z-boson p T distribution (<p T (Z)>.5 GeV/c) compared with PYTHIA Tune A (<p T (Z)> = 9.7 GeV/c), and PYTHIA Tune AW (<p T (Z)> =.7 GeV/c). Effective Q cut-off, below which space-like showers are not evolved. The Q 2 = k T2 in α s for space-like showers is scaled by PARP(64)! Rick Field Florida/CDF/CMS Page 43

Jet-Jet Correlations (DØ) Jet#-Jet#2 Distribution Jet#-Jet#2 MidPoint Cone Algorithm (R = 0.7, f merge = 0.5) L= 50 pb - (Phys. Rev. Lett. 94 2280 (2005)) Data/NLO agreement good. Data/HERWIG agreement good. Data/PYTHIA agreement good provided PARP(67) = 4.0 (i.e. like Tune A, best fit 2.5). Rick Field Florida/CDF/CMS Page 44

CDF Run P (Z) T PYTHIA 6.2 CTEQ5L Z-Boson Transverse Momentum UE Parameters Parameter MSTP(8) MSTP(82) PARP(82) PARP(83) PARP(84) PARP(85) Tune DW 4.9 GeV 0.5 Tune AW 4 2.0 GeV 0.5 0.9 PT Distribution /N dn/dpt 0.2 8 4 CDF Run Data PYTHIA Tune DW HERWIG CDF Run published.8 TeV Normalized to ISR Parameters PARP(86) PARP(89) PARP(90) PARP(62) PARP(64) PARP(67).8 TeV 0.25.25 0.2 2.5 0.95.8 TeV 0.25.25 0.2 4.0 0 0 2 4 6 8 0 2 4 6 8 20 Z-Boson PT (GeV/c) Shows the Run Z-boson p T distribution (<p T (Z)>.5 GeV/c) compared with PYTHIA Tune DW, and HERWIG. MSTP(9) PARP(9) 2. 2. PARP(93) 5.0 5.0 Intrensic KT Tune DW uses D0 s perfered value of PARP(67)! Tune DW has a lower value of PARP(67) and slightly more MPI! Rick Field Florida/CDF/CMS Page 45

All use LO α s with Λ = 92 MeV! Parameter Tune AW Tune DW Tune D6 PYTHIA 6.2 Tunes PDF CTEQ5L CTEQ5L CTEQ6L UE Parameters MSTP(8) MSTP(82) PARP(82) 4 2.0 GeV 4.9 GeV 4.8 GeV Uses CTEQ6L PARP(83) PARP(84) PARP(85) 0.5 0.9 0.5 0.5 Tune A energy dependence! (not the default) ISR Parameter PARP(86) PARP(89) 0.95.8 TeV.8 TeV.8 TeV PARP(90) 0.25 0.25 0.25 PARP(62).25.25.25 PARP(64) 0.2 0.2 0.2 PARP(67) 4.0 2.5 2.5 MSTP(9) PARP(9) 2. 2. 2. PARP(93) 5.0 5.0 5.0 Intrinsic KT Rick Field Florida/CDF/CMS Page 46

All use LO α s with Λ = 92 MeV! Parameter PYTHIA 6.2 Tunes Tune DWT Tune D6T ATLAS PDF CTEQ5L CTEQ6L CTEQ5L MSTP(8) UE Parameters MSTP(82) 4 4 4 PARP(82).9409 GeV.8387 GeV.8 GeV PARP(83) PARP(84) PARP(85) 0.5 0.5 0.5 0.5 0.33 ATLAS energy dependence! (PYTHIA default) ISR Parameter PARP(86) PARP(89).96 TeV.96 TeV 0.66 TeV PARP(90) 0.6 0.6 0.6 PARP(62).25.25 PARP(64) 0.2 0.2 PARP(67) 2.5 2.5 MSTP(9) PARP(9) 2. 2. PARP(93) 5.0 5.0 5.0 Intrinsic KT Rick Field Florida/CDF/CMS Page 47

PYTHIA 6.2 Tunes All use LO α s with Λ = 92 MeV! Tune A UE Parameters ISR Parameter Tune D Intrinsic KT Parameter Tune DWT PDF CTEQ5L MSTP(8) MSTP(82) 4 PARP(82).9409 GeV PARP(83) 0.5 PARP(84) Tune AW PARP(85) PARP(86) PARP(89).96 TeV PARP(90) 0.6 PARP(62).25 PARP(64) 0.2 PARP(67) 2.5 MSTP(9) PARP(9) Tune 2. DW PARP(93) 5.0 Tune D6T CTEQ6L 4.8387 GeV 0.5 Tune B.96 TeV 0.6.25 0.2 2.5 2. 5.0 ATLAS CTEQ5L 4.8 GeV 0.5 0.5 0.33 0.66 TeV 0.6 Tune D6 5.0 ATLAS energy dependence! (PYTHIA default) Tune BW Tune D6T Rick Field Florida/CDF/CMS Page 48

PYTHIA 6.2 Tunes All use LO α s with Λ = 92 MeV! Tune A UE Parameters ISR Parameter Tune D Intrinsic KT Parameter PDF MSTP(8) MSTP(82) PARP(82) CTEQ5L Tune D6T CTEQ6L.8387 GeV PARP(83) 0.5 0.5 0.5 PARP(84) Tune B 0.5 PARP(85) 0.33 These are old PYTHIA 6.2 tunes! PARP(86) 0.66 There are new 6.420 tunes by PARP(89).96 TeV.96 TeV TeV Tune AW PARP(64) PARP(67) PARP(93) Tune DWT.9409 GeV 0.2 2.5 MSTP(9) PARP(9) Tune 2. DW 4 5.0 4 0.2 2.5 2. 5.0 ATLAS CTEQ5L 4.8 GeV Tune D6 5.0 ATLAS energy dependence! (PYTHIA default) Tune BW Peter Skands (Tune S320, update of S0) PARP(90) 0.6 0.6 0.6 Peter Skands (Tune N324, N0CR) PARP(62).25.25 Hendrik Hoeth (Tune P329, Professor ) Tune D6T Rick Field Florida/CDF/CMS Page 49

JIMMY Runs with HERWIG and adds multiple parton interactions! The Energy in the Underlying Event in High P T Jet Production JIMMY: MPI J. M. Butterworth J. R. Forshaw M. H. Seymour Jet # Direction JIMMY at CDF PT(JIM)= 2.5 GeV/c. PT(JIM)= 3.25 GeV/c. "Transverse" ETsum Density (GeV) 4.0 3.0 2.0.96 TeV "Transverse" ETsum Density: det/dηdφ JIMMY Default JM325 generator level theory PY Tune A 0 00 200 300 400 500 PT(particle jet#) (GeV/c) JIMMY was tuned to fit the energy density in the transverse region for leading jet events! "Leading Jet" MidPoint R = 0.7 η(jet) < 2 All Particles ( η <) Final-State Radiation PT(hard) <Densities> vs P T (jet#) "Transverse" PTsum Density (GeV/c).6.2 0.8.96 TeV "Transverse" PTsum Density: dpt/dηdφ JIMMY Default generator level theory JM325 PY Tune A 0 50 00 50 200 250 300 350 400 450 500 PT(particle jet#) (GeV/c) "Leading Jet" MidPoint R = 0.7 η(jet) < 2 Rick Field Florida/CDF/CMS Page 50

JIMMY Runs with HERWIG and adds multiple parton interactions! The Energy in the Underlying Event in High P T Jet Production JIMMY: MPI J. M. Butterworth J. R. Forshaw M. H. Seymour Jet # Direction Final-State Radiation <Densities> vs P T (jet#) JIMMY at CDF PT(hard) PT(JIM)= 2.5 GeV/c. PT(JIM)= 3.25 GeV/c. "Transverse" ETsum Density (GeV) "Transverse" PTsum Density: dpt/dηdφ JMRAD(9).6 =.8 JIMMY Default "Transverse" PTsum Density (GeV/c) 4.0 3.0 2.0.2 0.8.96 TeV.96 TeV "Transverse" ETsum Density: det/dηdφ JIMMY Default generator level theory 0 00 200 300 400 500 JM325 The Drell-Yan JIMMY Tune PTJIM = 3.6 GeV/c, JMRAD(73) =.8 generator level theory PT(particle jet#) (GeV/c) JM325 PY Tune A PY Tune A 0 50 00 50 200 250 300 350 400 450 500 PT(particle jet#) (GeV/c) JIMMY was tuned to fit the energy density in the transverse region for leading jet events! "Leading Jet" MidPoint R = 0.7 η(jet) < 2 All Particles ( η <) "Leading Jet" MidPoint R = 0.7 η(jet) < 2 Rick Field Florida/CDF/CMS Page 5

Towards,, Leading Jet Jet # Direction Average Charged Density 5 4 3 2 0 Charged Particle Density: dn/dηdφ pya generator level "Transverse" 0 50 00 50 200 250 300 350 400 PT(jet#) (GeV/c) "Away" Factor of ~4.5 "Toward" "Leading Jet" MidPoint R=0.7 η(jet#) <2 Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for leading jet events as a function of the leading jet p T for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune A at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 52

Towards,, Leading Jet Jet # Direction Charged Average PTsum Charged Density Density (GeV/c) 4 3 2 Charged PTsum Particle Density: dpt/dηdφ dn/dηdφ 0 5 CDF CDF Run Run 2 Preliminary 2 Preliminary pya generator level pya generator level "Toward" "Away" "Transverse" "Away" Factor of ~6 "Toward" "Transverse" "Leading Jet" MidPoint R=0.7 η(jet#) <2 Factor of ~4.5 "Leading Jet" MidPoint R=0.7 η(jet#) <2 0 0. 0 0 50 50 00 00 50 50 200 200 250 250 300 300 350 400 PT(jet#) (GeV/c) (GeV/c) Data at.96 TeV on the charged density of particle charged scalar particles, p dn/dηdφ, with p T > 0.5 GeV/c and η < for leading T sum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for jet leading events as jet a function events as of a the function leading of jet the p T leading for the jet toward, p away, and transverse regions. The T for the toward, away, and transverse regions. data are corrected The data are to the corrected particle to level the (with particle errors level that (with include errors both that the include statistical both error the statistical and the systematic error and the uncertainty) systematic and uncertainty) are compared and are with compared PYTHIA with Tune PYTHIA A at the Tune particle A at level the (i.e. particle generator level (i.e. level). generator level). Rick Field Florida/CDF/CMS Page 53

Towards,, Leading Jet Jet # Direction Charged Average ETsum PTsum Density Charged Density (GeV) Density (GeV/c) 3 Charged ETsum PTsum Particle Density: Density: det/dηdφ dpt/dηdφ dn/dηdφ 0 5 CDF CDF Run Run 2 Preliminary 2 Preliminary 4 "Toward" pya generator level pya generator level "Toward" "Away" "Away" "Away" Factor of ~3 "Toward" "Transverse" Factor of ~6 "Transverse" "Leading Jet" 2 Factor of MidPoint ~4.5 R=0.7 η(jet#) <2 "Transverse" "Leading Jet" "Leading Jet" MidPoint R=0.7 η(jet#) <2 MidPoint R=0.7 η(jet#) <2 pya generator level Charged Stable Particles Particles ( η <, ( η <, PT>0.5 all GeV/c) PT) 0 0. 0 50 50 00 50 200 250 300 0 50 00 50 200 250 300 350 400 (GeV/c) PT(jet#) (GeV/c) density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for leading Data jet events at.96 as TeV a function on the particle charged of the leading scalar particle jet E scalar p T sum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < T p sum T for density, the toward, det/dηdφ, away, for η and < transverse for leading regions. jet events The as a function for leading of the jet leading events jet as pa function of the leading jet p T for the toward, away, and transverse regions. data are corrected The data are to the corrected particle T for the toward, away, and transverse regions. The data are corrected to level the (with particle errors level that (with include errors both that the include statistical both error the statistical and the systematic to the particle level (with errors that include both the statistical error and the systematic uncertainty) error and and are the uncertainty) systematic and uncertainty) are compared and are with compared PYTHIA with Tune PYTHIA A at the Tune particle A at level the (i.e. particle generator level (i.e. level). compared with PYTHIA Tune A at the particle level (i.e. generator level). generator level). Rick Field Florida/CDF/CMS Page 54

Charged Particle Density Charged Particle Density: dn/dηdφ Charged Particle Density: dn/dηdφ Average Charged Density 3 2 0 pyaw generator level "Drell-Yan Production" 70 < M(pair) < 0 GeV "Toward" "Away" "Transverse" 0 20 40 60 80 00 Average Charged Density 4 3 2 0 pya generator level "Transverse" "Away" "Toward" "Leading Jet" MidPoint R=0.7 η(jet#) <2 0 20 40 60 80 00 20 40 60 80 200 PT(Z-Boson) (GeV/c) PT(jet#) (GeV/c) Z-Boson Direction High P T Z-Boson Production Jet # Direction PT(hard) Z-boson Final-State Radiation Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson and Leading Jet events as a function of the leading jet p T or P T (Z) for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 55

Charged Particle Density "Transverse" Average Charged Density.2 3 0.9 2 0.6 0.3 "Transverse" Charged Charged Particle Particle Density: Density: dn/dηdφ dn/dηdφ CDF CDF Run Run 2 2 Preliminary Preliminary generator level theory pyaw generator level "Drell-Yan Production" 70 < M(pair) < 0 GeV "Z-Boson" "Leading "Away" Jet" "Transverse" "Toward" 0 00 20 2040 60 40 80 00 60 20 40 80 60 80 00 200 PT(jet#) PT(Z-Boson) or PT(Z-Boson) (GeV/c) (GeV/c) Average "Away" Charged Charged Density Density 4 3 2 "Away" Charged Charged Particle Particle Density: Density: dn/dηdφ dn/dηdφ CDF Run Run 22 Preliminary data data corrected corrected generator pya generator level level theory "Leading Jet" "Z-Boson""Transverse" "Away" 0 0 20 40 60 80 00 20 40 60 80 200 PT(jet#) PT(jet#) or PT(Z-Boson) (GeV/c) (GeV/c) "Toward" "Leading Jet" MidPoint R=0.7 η(jet#) <2 Z-Boson Direction High P T Z-Boson Production Jet # Direction PT(hard) Z-boson Final-State Radiation Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson and Leading Jet events as a function of the leading jet p T or P T (Z) for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 56

"Transverse" Average Charged Density.2 3 0.9 2 0.6 0.3 Charged Particle Density HERWIG + JIMMY "Transverse" Charged Charged Particle Particle Density: Density: dn/dηdφ "Away" dn/dηdφcharged Particle Density: "Away" dn/dηdφ Charged Charged Particle Particle Density: Tune Density: dn/dηdφ (PTJIM = 3.6) dn/dηdφ CDF CDF Run Run 2 2 Preliminary Preliminary generator level theory pyaw generator level "Drell-Yan Production" 70 < M(pair) < 0 GeV "Z-Boson" "Away" Charged Density 3 "Leading "Away" Jet" generator level theory 2 "Transverse" "Drell-Yan Production" 70 < M(pair) < 0 GeV pyaw Average "Away" Charged Charged Density Density "Toward" Charged Particles ( η <, PT>0.5 GeV/c) 0 0 0 00 20 2040 60 40 80 00 60 20 40 80 60 80 00 200 0 20 40 60 80 00 20 40 60 80 200 0 20 40 60 80 00 PT(jet#) PT(Z-Boson) or PT(Z-Boson) (GeV/c) (GeV/c) PT(jet#) PT(jet#) or PT(Z-Boson) (GeV/c) (GeV/c) PT(Z-Boson) (GeV/c) 4 3 2 CDF Run Run 22 Preliminary data data corrected corrected generator pya generator level level theory JIM "Leading Jet" "Z-Boson""Transverse" "Away" "Toward" "Leading Jet" MidPoint R=0.7 η(jet#) <2 Z-Boson Direction High P T Z-Boson Production Jet # Direction PT(hard) Z-boson Final-State Radiation Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson and Leading Jet events as a function of the leading jet p T or P T (Z) for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 57

"Transverse" Average Charged Density.2 3 0.9 2 0.6 0.3 Charged Particle Density HERWIG + JIMMY H. Hoeth, MPI@LHC08 "Transverse" Charged Charged Particle Particle Density: Density: dn/dηdφ "Away" dn/dηdφcharged Particle Density: "Away" dn/dηdφ Charged Charged Particle Particle Density: Tune Density: dn/dηdφ (PTJIM = 3.6) dn/dηdφ CDF CDF Run Run 2 2 Preliminary Preliminary generator level theory pyaw generator level "Drell-Yan Production" 70 < M(pair) < 0 GeV "Z-Boson" "Away" Charged Density 3 "Leading "Away" Jet" generator level theory 2 "Transverse" "Drell-Yan Production" 70 < M(pair) < 0 GeV pyaw Average "Away" Charged Charged Density Density "Toward" Charged Particles ( η <, PT>0.5 GeV/c) 0 0 0 00 20 2040 60 40 80 00 60 20 40 80 60 80 00 200 0 20 40 60 80 00 20 40 60 80 200 0 20 40 60 80 00 PT(jet#) PT(Z-Boson) or PT(Z-Boson) (GeV/c) (GeV/c) PT(jet#) PT(jet#) or PT(Z-Boson) (GeV/c) (GeV/c) PT(Z-Boson) (GeV/c) 4 3 2 CDF Run Run 22 Preliminary data data corrected corrected generator pya generator level level theory JIM "Leading Jet" "Z-Boson""Transverse" "Away" "Toward" "Leading Jet" MidPoint R=0.7 η(jet#) <2 Z-Boson Direction High P T Z-Boson Production Jet # Direction PT(hard) Z-boson Final-State Radiation Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson and Leading Jet events as a function of the leading jet p T or P T (Z) for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 58

Charged PTsum Density Charged PTsum Density: dpt/dηdφ Charged PTsum Density: dpt/dηdφ Charged PTsum Density (GeV/c) 0. pyaw generator level "Drell-Yan Production" 70 < M(pair) < 0 GeV "Away" "Transverse" "Toward" 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) Charged PTsum Density (GeV/c) 0 0. pya generator level "Toward" "Away" "Transverse" 0 20 40 60 80 00 20 40 60 80 200 PT(jet#) (GeV/c) "Leading Jet" MidPoint R=0.7 η(jet#) <2 Z-Boson Direction High P T Z-Boson Production Jet # Direction PT(hard) Z-boson Final-State Radiation Data at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for Z- Boson and Leading Jet events as a function of the leading jet p T or P T (Z) for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 59

Charged PTsum Density "Transverse" Charged PTsum Density (GeV/c) 2.0.5 "Transverse" Charged Charged PTsum PTsum Density: Density: dpt/dηdφ dpt/dηdφ CDF CDF Run Run 22 Preliminary data data corrected corrected pyaw generator level generator level theory "Away" "Leading Jet" "Transverse" "Toward" 0.5 "Drell-Yan Production" 70 < M(pair) < 0 GeV "Z-Boson" 0. 00 20 40 20 60 80 40 00 20 60 40 60 80 80 200 00 PT(jet#) PT(Z-Boson) or PT(Z-Boson) (GeV/c) (GeV/c) Charged "Away" PTsum Density (GeV/c) "Away" Charged Charged PTsum PTsum Density: Density: dpt/dηdφ dpt/dηdφ 0 20 CDF CDF Run Run 2 Preliminary 2 data corrected "Leading Jet" pya generator level 5 generator level theory "Toward" "Away" 0 "Z-Boson" "Transverse" 5 "Leading Jet" MidPoint R=0.7 η(jet#) <2 00. 0 0 20 20 40 40 60 60 80 80 00 00 20 40 60 80 200 PT(jet#) PT(jet#) or PT(Z-Boson) (GeV/c) (GeV/c) Z-Boson Direction High P T Z-Boson Production Jet # Direction PT(hard) Z-boson Final-State Radiation Data at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for Z- Boson and Leading Jet events as a function of the leading jet p T or P T (Z) for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 60

"Transverse" Charged PTsum Density (GeV/c) Charged PTsum Density "Transverse" Charged Charged PTsum PTsum Density: Density: dpt/dηdφ dpt/dηdφ "Away" Charged PTsum Density: "Away" dpt/dηdφ Charged Charged PTsum PTsum Density: Density: dpt/dηdφ dpt/dηdφ 2.0 2 0 20 CDF CDF Run Run 22 Preliminary "Away" CDF CDF Run Run 2 Preliminary 2 "Leading Jet" data corrected pyaw generator level "Leading Jet" pya generator level.5 generator level theory generator level theory 5pyAW generator level theory "Toward" 8 "Drell-Yan Production" "Transverse" "Away" 70 < M(pair) < 0 GeV 0 "Z-Boson" JIM "Transverse" 4 "Toward" "Leading Jet" 0.5 5 "Drell-Yan Production" MidPoint R=0.7 η(jet#) <2 70 < M(pair) < 0 GeV "Z-Boson" 0. 0 00. 00 20 40 20 60 80 40 00 20 60 0 40 60 80 20 80 200 00 40 0 060 20 20 40 4080 60 60 80 8000 00 00 20 40 60 80 200 PT(jet#) PT(Z-Boson) or PT(Z-Boson) (GeV/c) (GeV/c) PT(Z-Boson) (GeV/c) PT(jet#) PT(jet#) or PT(Z-Boson) (GeV/c) (GeV/c) "Away" PTsum Density (GeV/c) Charged "Away" PTsum Density (GeV/c) Z-Boson Direction High P T Z-Boson Production Jet # Direction PT(hard) Z-boson Final-State Radiation Data at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for Z- Boson and Leading Jet events as a function of the leading jet p T or P T (Z) for the toward, away, and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 6

The TransMAX/MIN Regions "Transverse" Charged Density.6.2 "TransMAX/MIN" Charged Particle Density: dn/dηdφ generator level theory "Drell-Yan Production" 70 < M(pair) < 0 GeV 0.8 ATLAS pyaw JIM "transmax" pydw "transmin" 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) "Transverse" Charged Density.6.2 0.8 "TransMAX/MIN" Charged Particle Density: dn/dηdφ generator level theory "transmax" "transmin" 0 50 00 50 200 250 300 350 400 PT(jet#) (GeV/c) "Leading Jet" MidPoint R=0.7 η(jet#) <2 PY Tune A Z-Boson Direction TransMAX TransMIN High P T Z-Boson Production Jet # Direction TransMAX TransMIN PT(hard) Z-boson Final-State Radiation Data at at.96 TeVon on the the charged density of particle charged density, particles, dn/dηdφ, dn/dηdφ, with with p T > p0.5 GeV/c and η < for Z-Boson and T > 0.5 GeV/c and η < for leading Leading jet events Jet as a events function as a of function the leading of P T jet (Z) por the leading jet p T for the transmax, and transmin regions. T and for Z-Boson events as a function of P T (Z) for TransDIF = The transmax data are corrected minus transmin to the particle regions. level (with The data errors are that corrected include to both the the particle statistical level error (with and errors the that systematic include uncertainty) both the statistical and are error compared and the with systematic PYTHIA uncertainty) Tune AW and and are Tune compared A, respectively, with PYTHIA at the particle Tune A and level (i.e. generator HERWIG level). (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 62

The TransMAX/MIN Regions "Transverse" TransMAX - TransMIN Charged Density.2.6 0.9.2 0.6 0.8 "TransMAX/MIN" "TransDIF" Charged Charged Particle Particle Density: Density: dn/dηdφ dn/dηdφ generator level theory "Drell-Yan Production" 70 70 < < M(pair) < < 0 0 GeV GeV pyaw pyaw JIM "transmax" pydw ATLAS "transmin" 0.3 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) TransMAX "Transverse" - TransMIN Charged Density.2.6 0.9.2 0.6 0.8 0.3 "TransMAX/MIN" "TransDIF" Charged Particle Density: dn/dηdφ data data corrected corrected generator generator level level theory theory "transmax" "transmin" "Leading Jet" MidPoint R=0.7 η(jet#) <2 PY Tune A PY Tune A "Leading Jet" MidPoint R=0.7 η(jet#) <2 0 50 00 50 200 250 300 300 350 350 400 400 PT(jet#) (GeV/c) Z-Boson Direction TransMAX TransMIN High P T Z-Boson Production Jet # Direction TransMAX TransMIN PT(hard) Z-boson Final-State Radiation Data at at.96 TeVon on the the charged density of particle charged density, particles, dn/dηdφ, dn/dηdφ, with with p T > p0.5 GeV/c and η < for Z-Boson and T > 0.5 GeV/c and η < for leading Leading jet events Jet as a events function as a of function the leading of P T jet (Z) por the leading jet p T for the transmax, and transmin regions. T and for Z-Boson events as a function of P T (Z) for TransDIF = The transmax data are corrected minus transmin to the particle regions. level (with The data errors are that corrected include to both the the particle statistical level error (with and errors the that systematic include uncertainty) both the statistical and are error compared and the with systematic PYTHIA uncertainty) Tune AW and and are Tune compared A, respectively, with PYTHIA at the particle Tune A and level (i.e. generator HERWIG level). (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 63

The TransMAX/MIN Regions "Transverse" TransMAX - TransMIN Charged Density.2.6 0.9.2 0.6 0.8 "TransMAX/MIN" "TransDIF" Charged Charged Particle Particle Density: Density: dn/dηdφ dn/dηdφ generator level theory "Drell-Yan Production" "transmax" 70 70 < < M(pair) < < 0 0 GeV GeV pyaw pydw pyaw JIM pydw JIM ATLAS 0.3 "transmin" ATLAS 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) TransMAX "Transverse" - TransMIN Charged Density.2.6 0.9.2 0.6 0.8 0.3 "TransMAX/MIN" "TransDIF" Charged Particle Density: dn/dηdφ data data corrected corrected generator generator level level theory theory "transmax" "transmin" "Leading Jet" MidPoint R=0.7 η(jet#) <2 PY Tune A PY Tune A "Leading Jet" MidPoint R=0.7 η(jet#) <2 0 50 00 50 200 250 300 300 350 350 400 400 PT(jet#) (GeV/c) Z-Boson Direction TransMAX TransMIN High P T Z-Boson Production Jet # Direction TransMAX TransMIN PT(hard) Z-boson Final-State Radiation Data at at.96 TeVon on the the charged density of particle charged density, particles, dn/dηdφ, dn/dηdφ, with with p T > p0.5 GeV/c and η < for Z-Boson and T > 0.5 GeV/c and η < for leading Leading jet events Jet as a events function as a of function the leading of P T jet (Z) por the leading jet p T for the transmax, and transmin regions. T and for Z-Boson events as a function of P T (Z) for TransDIF = The transmax data are corrected minus transmin to the particle regions. level (with The data errors are that corrected include to both the the particle statistical level error (with and errors the that systematic include uncertainty) both the statistical and are error compared and the with systematic PYTHIA uncertainty) Tune AW and and are Tune compared A, respectively, with PYTHIA at the particle Tune A and level (i.e. generator HERWIG level). (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 64

The TransMAX/MIN Regions "Transverse" TransMAX - TransMIN Charged Density.2.6 0.9.2 0.6 0.8 "TransMAX/MIN" "TransDIF" Charged Charged Particle Particle Density: Density: dn/dηdφ "TransDIF" dn/dηdφ Charged Particle "TransMAX/MIN" Density: "TransDIF" dn/dηdφ Charged Particle Density: dn/dηdφ generator level theory "Drell-Yan Production" 70 70 < < M(pair) < < 0 0 GeV GeV.2 pyaw pydw pyaw JIM generator level theory 0.9 "transmax" "TransDIF" Charged Density 0.6 TransMAX "Transverse" - TransMIN Charged Density pydw JIM ATLAS "transmin" 0.3 "transmin" "Leading Jet" 0.3 "Z-Boson" 0.3 ATLAS MidPoint R=0.7 η(jet#) <2 0 20 40 60 0 2080 40 6000 80 000 20 50 40 00 60 50 80 200 200 250 300 300 350 350 400 400 PT(Z-Boson) (GeV/c) PT(jet#) or PT(Z-Boson) (GeV/c) PT(jet#) (GeV/c).2.6 0.9.2 0.6 0.8 "Leading data data corrected corrected Jet" generator generator level level theory theory "transmax" "Leading Jet" MidPoint R=0.7 η(jet#) <2 PY Tune A PY Tune A Z-Boson Direction TransMAX TransMIN High P T Z-Boson Production Jet # Direction TransMAX TransMIN PT(hard) Z-boson Final-State Radiation Data at at.96 TeVon on the the charged density of particle charged density, particles, dn/dηdφ, dn/dηdφ, with with p T > p0.5 GeV/c and η < for Z-Boson and T > 0.5 GeV/c and η < for leading Leading jet events Jet as a events function as a of function the leading of P T jet (Z) por the leading jet p T for the transmax, and transmin regions. T and for Z-Boson events as a function of P T (Z) for TransDIF = The transmax data are corrected minus transmin to the particle regions. level (with The data errors are that corrected include to both the the particle statistical level error (with and errors the that systematic include uncertainty) both the statistical and are error compared and the with systematic PYTHIA uncertainty) Tune AW and and are Tune compared A, respectively, with PYTHIA at the particle Tune A and level (i.e. generator HERWIG level). (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 65

The TransMAX/MIN Regions "TransMAX/MIN" Charged PTsum Density "TransMAX/MIN" Charged PTsum Density "Transverse" PTsum Density (GeV/c) 3.0 2.0 generator level theory "Drell-Yan Production" 70 < M(pair) < 0 GeV "transmax" pyaw "transmin" 0 20 40 60 80 00 "Transverse" PTsum Density (GeV/c) 3.0 2.0 generator level theory "transmax" "transmin" PY Tune A "Leading Jet" MidPoint R=0.7 η(jet#) <2 0 50 00 50 200 250 300 350 400 PT(Z-Boson) (GeV/c) PT(jet#) (GeV/c) Z-Boson Direction TransMAX TransMIN High P T Z-Boson Production Jet # Direction TransMAX TransMIN PT(hard) Z-boson Final-State Radiation Data at at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p Z- T > 0.5 GeV/c and η < for Boson leading and jet Leading events as Jet a function events as of the a function leading of jet P T p(z) or the leading jet p T for the transmax, and T and for Z-Boson events as a function of P T (Z) for transmin TransDIF regions. = transmax The data minus are corrected transmin to the regions. particle The level data (with are errors corrected that to include the particle both the level statistical (with errors and that the include systematic both the uncertainty) statistical and error are and compared the systematic with PYTHIA uncertainty) Tune and AW are and compared Tune A, with respectively, PYTHIA at the particle Tune A level and HERWIG (i.e. generator (without level). MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 66

The TransMAX/MIN Regions TransMAX "Transverse" - TransMIN PTsum Density (GeV/c) 3.0 2.0 "TransDIF" "TransMAX/MIN" Charged Charged PTsum Density: PTsum Density dpt/dηdφ generator level theory "Drell-Yan Production" 70 < "Drell-Yan M(pair) < Production" "transmax" 0 GeV 70 < M(pair) < 0 GeV pyaw pyaw "transmin" 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) "Transverse" PTsum Density (GeV/c) TransMAX - TransMIN Density (GeV/c) 2.0 2.0 "TransDIF" "TransMAX/MIN" Charged Charged PTsum PTsum Density: Density dpt/dηdφ 3.0 3.0 CDF Run 22 Preliminary data generator level level theory PY Tune A "transmax" PY Tune A "Leading Jet" "Leading Jet" MidPoint R=0.7 η(jet#) <2 MidPoint R=0.7 η(jet#) <2 "transmin" 0 0 50 50 00 00 50 50 200 200 250 250 300 300 350 400 PT(jet#) (GeV/c) Z-Boson Direction TransMAX TransMIN High P T Z-Boson Production Jet # Direction TransMAX TransMIN PT(hard) Z-boson Final-State Radiation Data at at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p Z- T > 0.5 GeV/c and η < for Boson leading and jet Leading events as Jet a function events as of the a function leading of jet P T p(z) or the leading jet p T for the transmax, and T and for Z-Boson events as a function of P T (Z) for transmin TransDIF regions. = transmax The data minus are corrected transmin to the regions. particle The level data (with are errors corrected that to include the particle both the level statistical (with errors and that the include systematic both the uncertainty) statistical and error are and compared the systematic with PYTHIA uncertainty) Tune and AW are and compared Tune A, with respectively, PYTHIA at the particle Tune A level and HERWIG (i.e. generator (without level). MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 67

The TransMAX/MIN Regions TransMAX "Transverse" - TransMIN PTsum Density (GeV/c) 3.0 2.0 "TransDIF" "TransMAX/MIN" Charged Charged PTsum Density: PTsum Density dpt/dηdφ "TransDIF" Charged PTsum Density: "TransDIF" "TransMAX/MIN" dpt/dηdφ Charged Charged PTsum PTsum Density: Density dpt/dηdφ 3.0 generator level theory generator level theory pyaw 2.0 "Drell-Yan Production" "transmax" pyaw "Z-Boson" 70 < "Drell-Yan M(pair) < Production" 0 GeV 70 < M(pair) < 0 GeV "TransDIF" PTsum Density (GeV/c) "Leading Jet" "Leading Jet" MidPoint R=0.7 η(jet#) <2 MidPoint R=0.7 η(jet#) <2 "transmin" "transmin" 0 20 40 60 0 20 80 40 60 0080 000 0 20 50 5040 00 00 60 80 50 50 200 200 200 250 250 300 300 350 400 PT(Z-Boson) (GeV/c) "Transverse" PTsum Density (GeV/c) TransMAX - TransMIN Density (GeV/c) 3.0 3.0 CDF Run 22 Preliminary data generator "Leading level level theory Jet" 2.0 2.0 PY Tune A PT(jet#) or PT(Z-Boson) (GeV/c) "transmax" PY Tune A PT(jet#) (GeV/c) Z-Boson Direction TransMAX TransMIN High P T Z-Boson Production Jet # Direction TransMAX TransMIN PT(hard) Z-boson Final-State Radiation Data at at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p Z- T > 0.5 GeV/c and η < for Boson leading and jet Leading events as Jet a function events as of the a function leading of jet P T p(z) or the leading jet p T for the transmax, and T and for Z-Boson events as a function of P T (Z) for transmin TransDIF regions. = transmax The data minus are corrected transmin to the regions. particle The level data (with are errors corrected that to include the particle both the level statistical (with errors and that the include systematic both the uncertainty) statistical and error are and compared the systematic with PYTHIA uncertainty) Tune and AW are and compared Tune A, with respectively, PYTHIA at the particle Tune A level and HERWIG (i.e. generator (without level). MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 68

Charged Particle <p< T > "Transverse" Average PT (GeV/c) 2.0.5 0.5 generator level theory "Transverse" Average PT PY Tune A "Leading Jet" MidPoint R=0.7 η(jet#) <2 0 50 00 50 200 250 300 350 400 "Toward" <PT> (GeV/c).6.2 0.8 "Toward" Average PT Charged generator level theory pydw JIM pyaw ATLAS "Drell-Yan Production" 70 < M(pair) < 0 GeV 0 20 40 60 80 00 PT(jet#) (GeV/c) PT(Z-Boson) (GeV/c) Jet # Direction Z-BosonDirection Data at.96 TeV on the charged particle average p T, with p T > 0.5 GeV/c and η < for the toward region for Z-Boson and the transverse region for Leading Jet events as a function of the leading jet p T or P T (Z). The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). The Z-Boson data are also compared with PYTHIA Tune DW, the ATLAS tune, and HERWIG (without MPI) Rick Field Florida/CDF/CMS Page 69

Charged Particle <p< T > H. Hoeth, MPI@LHC08 "Transverse" Average PT (GeV/c) 2.0.5 0.5 generator level theory "Transverse" Average PT PY Tune A "Leading Jet" MidPoint R=0.7 η(jet#) <2 0 50 00 50 200 250 300 350 400 "Toward" <PT> (GeV/c).6.2 0.8 "Toward" Average PT Charged generator level theory pydw JIM pyaw ATLAS "Drell-Yan Production" 70 < M(pair) < 0 GeV 0 20 40 60 80 00 PT(jet#) (GeV/c) PT(Z-Boson) (GeV/c) Jet # Direction Z-BosonDirection Data at.96 TeV on the charged particle average p T, with p T > 0.5 GeV/c and η < for the toward region for Z-Boson and the transverse region for Leading Jet events as a function of the leading jet p T or P T (Z). The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and Tune A, respectively, at the particle level (i.e. generator level). The Z-Boson data are also compared with PYTHIA Tune DW, the ATLAS tune, and HERWIG (without MPI) Rick Field Florida/CDF/CMS Page 70

Charged Density 0.9 0.6 0.3 Z-Boson: Towards,, Transverse, & TransMIN Charge Density Charged Particle Density: dn/dηdφ pyaw generator level "Transverse "Toward" "Drell-Yan Production" 70 < M(pair) < 0 GeV 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) Charged Density 0.9 0.6 0.3 High Charged P T Z-Boson Particle Production Density: dn/dηdφ pyaw generator level "Toward" Z-boson Z-boson "transmin" "Drell-Yan Production" 70 < M(pair) < 0 GeV 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z- Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 7

"Toward" Charged Charged Density Density Z-Boson: Towards,, Transverse, & TransMIN Charge Density "Toward" Charged Charged Particle Particle Density: Density: dn/dηdφ dn/dηdφ 0.9 CDF Run Preliminary "Transverse pydw pyaw data generator correctedlevel ATLAS JIM generator level theory 0.6 "Toward" 0.3 pyaw "Drell-Yan Production" 70 70 < M(pair) < 0 GeV 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) "TransMIN" Charged Charged Density Density 0.9 0.6 0.6 "TransMIN" High Charged P T Z-Boson Charged Particle Production Particle Density: Density: dn/dηdφ dn/dηdφ generator pyaw generator level theory level JIM "Toward" 0.3 0.2 Z-boson Z-boson "transmin" pyaw "Drell-Yan Production" "Drell-Yan Production" 70 M(pair) < 0 GeV 70 < M(pair) < 0 GeV ATLAS pydw 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z- Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 72

"Toward" Charged Charged Density Density 0.9 0.6 Z-Boson: Towards,, Transverse, & TransMIN Charge Density "Toward" Charged Charged Particle Particle Density: Density: dn/dηdφ dn/dηdφ "TransMIN" Charged Particle Density: "TransMIN" High Charged dn/dηdφ P T Z-Boson Charged Particle Production Particle Density: Density: dn/dηdφ dn/dηdφ CDF Run Preliminary pyaw data generator correctedlevel generator level theory "Transverse ATLAS JIM 0.6 "Toward" "TransMIN" Charged Density 0.8 pydw generator level theory "TransMIN" Charged Charged Density Density generator pyaw generator level theory level "Leading Jet" JIM "Toward" "Drell-Yan Production" "Drell-Yan Production" 70 M(pair) < 0 GeV 70 < M(pair) < 0 GeV ATLAS pydw 0.3 0.3 0.2 Z-boson pyaw Z-boson 0.2 "Drell-Yan Production" "transmin" 70 70 < M(pair) < 0 GeV pyaw "Z-Boson" 0 20 40 60 0 20 80 40 60 00 80 00 0 20 40 20 60 80 40 200 60 80 00 PT(Z-Boson) (GeV/c) PT(jet#) or PT(Z-Boson) (GeV/c) PT(Z-Boson) (GeV/c) 0.9 0.6 0.6 Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z- Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 73

"Toward" Charged Charged Density Density 0.9 0.6 Z-Boson: Towards,, Transverse, & TransMIN H. Hoeth, MPI@LHC08 Charge Density "Toward" Charged Charged Particle Particle Density: Density: dn/dηdφ dn/dηdφ "TransMIN" Charged Particle Density: "TransMIN" High Charged dn/dηdφ P T Z-Boson Charged Particle Production Particle Density: Density: dn/dηdφ dn/dηdφ CDF Run Preliminary pyaw data generator correctedlevel generator level theory "Transverse ATLAS JIM 0.6 "Toward" "TransMIN" Charged Density 0.8 pydw generator level theory "TransMIN" Charged Charged Density Density generator pyaw generator level theory level "Leading Jet" JIM "Toward" "Drell-Yan Production" "Drell-Yan Production" 70 M(pair) < 0 GeV 70 < M(pair) < 0 GeV ATLAS pydw 0.3 0.3 0.2 Z-boson pyaw Z-boson 0.2 "Drell-Yan Production" "transmin" 70 70 < M(pair) < 0 GeV pyaw "Z-Boson" 0 20 40 60 0 20 80 40 60 00 80 00 0 20 40 20 60 80 40 200 60 80 00 PT(Z-Boson) (GeV/c) PT(jet#) or PT(Z-Boson) (GeV/c) PT(Z-Boson) (GeV/c) 0.9 0.6 0.6 Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the density of charged particles, dn/dηdφ, with p T > 0.5 GeV/c and η < for Z- Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 74

Charged PTsum Density (GeV/c).8.2 0.6 Z-Boson: Towards,, Transverse, & TransMIN Charge Density Charged PTsum Density: dpt/dηdφ pyaw generator level "Transverse "Toward" "Drell-Yan Production" 70 < M(pair) < 0 GeV 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) Charged PTsum Density (GeV/c).2 0.8 High Charged P T Z-Boson PTsum Production Density: dpt/dηdφ pyaw generator level "Toward" Z-boson Z-boson "transmin" 0 20 40 60 80 00 PT(Z-Boson) (GeV/c) "Drell-Yan Production" 70 < M(pair) < 0 GeV Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 75

"Toward" Charged PTsum Density (GeV/c).8.2 Z-Boson: Towards,, Transverse, & TransMIN Charge Density "Toward" Charged Charged PTsum PTsum Density: Density: dpt/dηdφ dpt/dηdφ pyaw generator generator level theory level "Drell-Yan Production" 70 < M(pair) < 0 GeV ATLAS.2 0.8 pydw "Transverse JIM 0.6 "Toward" pyaw 0 20 40 60 80 00 Charged PTsum Density (GeV/c) "TransMIN" PTsum Density (GeV/c).2 0.8 0.6 0.8 "TransMIN" High Charged P T Z-Boson Charged PTsum Production PTsum Density: Density: dpt/dηdφ dpt/dηdφ pyaw generator generator level theory level "Drell-Yan Production" "Drell-Yan Production" 70 < M(pair) < 0 GeV 70 < M(pair) < 0 GeV JIM ATLAS "Toward" pydw Z-boson 0.2 Z-boson "transmin" pyaw 00 20 20 40 40 60 60 80 80 00 00 PT(Z-Boson) (GeV/c) PT(Z-Boson) (GeV/c) Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 76

"Toward" Charged PTsum Density (GeV/c).8.2.2 0.8 Z-Boson: Towards,, Transverse, & TransMIN Charge Density "Toward" Charged Charged PTsum PTsum Density: Density: dpt/dηdφ dpt/dηdφ "TransMIN" Charged PTsum Density: "TransMIN" High Charged dpt/dηdφ P T Z-Boson Charged PTsum Production PTsum Density: Density: dpt/dηdφ dpt/dηdφ 0.8.2 0.8 "Drell-Yan Production" "Drell-Yan Production" "Drell-Yan Production" 70 < M(pair) < 0 GeV 70 < M(pair) < 0 GeV data ATLAS corrected 70 < M(pair) < 0 GeV pyaw generator generator level theory level generator level theory "Leading pyaw generator generator Jet" level theory level 0.6 0.6 pydw pydw 0.8 "Transverse "TransMIN" PTsum Density (GeV/c) Charged PTsum Density (GeV/c) "TransMIN" PTsum Density (GeV/c) ATLAS JIM "Toward" JIM 0.6 Z-boson Z-boson "Toward" 0.2 0.2 pyaw "transmin" "Z-Boson" Charged Particles pyaw ( η <, PT>0.5 GeV/c) 0 20 40 60 80 00 00 20 20 40 40 60 60 80 80 00 0 20 40 60 80 00 20 40 60 80 200 00 PT(Z-Boson) (GeV/c) PT(jet#) or PT(Z-Boson) (GeV/c) PT(Z-Boson) (GeV/c) Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 77

"Toward" Charged PTsum Density (GeV/c).8.2.2 0.8 Z-Boson: Towards,, Transverse, & TransMIN H. Hoeth, MPI@LHC08 Charge Density "Toward" Charged Charged PTsum PTsum Density: Density: dpt/dηdφ dpt/dηdφ "TransMIN" Charged PTsum Density: "TransMIN" High Charged dpt/dηdφ P T Z-Boson Charged PTsum Production PTsum Density: Density: dpt/dηdφ dpt/dηdφ 0.8.2 0.8 "Drell-Yan Production" "Drell-Yan Production" "Drell-Yan Production" 70 < M(pair) < 0 GeV 70 < M(pair) < 0 GeV data ATLAS corrected 70 < M(pair) < 0 GeV pyaw generator generator level theory level generator level theory "Leading pyaw generator generator Jet" level theory level 0.6 0.6 pydw pydw 0.8 "Transverse "TransMIN" PTsum Density (GeV/c) Charged PTsum Density (GeV/c) "TransMIN" PTsum Density (GeV/c) ATLAS JIM "Toward" JIM 0.6 Z-boson Z-boson "Toward" 0.2 0.2 pyaw "transmin" "Z-Boson" Charged Particles pyaw ( η <, PT>0.5 GeV/c) 0 20 40 60 80 00 00 20 20 40 40 60 60 80 80 00 0 20 40 60 80 00 20 40 60 80 200 00 PT(Z-Boson) (GeV/c) PT(jet#) or PT(Z-Boson) (GeV/c) PT(Z-Boson) (GeV/c) Z-BosonDirection Z-Boson Direction TransMAX TransMIN Data at.96 TeV on the charged scalar PTsum density, dpt/dηdφ, with p T > 0.5 GeV/c and η < for Z-Boson events as a function of P T (Z) for the toward and transverse regions. The data are corrected to the particle level (with errors that include both the statistical error and the systematic uncertainty) and are compared with PYTHIA Tune AW and HERWIG (without MPI) at the particle level (i.e. generator level). Rick Field Florida/CDF/CMS Page 78