Two Particle Two Particle Production Production in Color Glass in Color Glass Condensate Condensate Jamal Jalilian-Marian Jamal Jalilian-Marian Institute for Nuclear Institute for Nuclear Theory Theory University of Washington University of Washington
Two Particle Production in Color Glass Condensate. Jamal Jalilian-Marian Institute for Nuclear Theory University of Washington. J.J-M. + Yu.K., hep-ph/0405266. Color Glass Condensate and High Energy Processes. Some Kinematics:DIS. - PowerPoint PPT Presentation
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Two Particle ProductionTwo Particle Productionin Color Glass Condensatein Color Glass Condensate
Jamal Jalilian-MarianJamal Jalilian-Marian
Institute for Nuclear TheoryInstitute for Nuclear Theory
Color Glass Condensate Color Glass Condensate and and
High Energy ProcessesHigh Energy Processes
Some Kinematics:DISSome Kinematics:DIS
F2, FL contain all the information about the hadron (quark and gluon distribution functions)F2 ~ [q (x,Q2) + q (x,Q2)]
Perturbative QCD in pp CollisionsPerturbative QCD in pp Collisions
Weak coupling (Weak coupling (ss << 1) << 1) Collinear factorizationCollinear factorization IncoherenceIncoherence Quark, gluon distribution functions: fQuark, gluon distribution functions: faa (x, Q (x, Q22)) Distributions are universal ---> Distributions are universal ---> predictabilitypredictability
+ 1/Q2
pQCDpQCD Expansion in the couplingExpansion in the coupling
Very often one picks up Very often one picks up large logarithms (phase large logarithms (phase space), need to resum space), need to resum
DGLAP:DGLAP: BFKL: BFKL: Growth of gluon Growth of gluon
distribution functiondistribution function Violation of unitarityViolation of unitarity Saturation Saturation
Gluon SaturationGluon Saturation
High gluon density effects regulate the low kt divergence present in pQCD
Most gluons have momentum ~ Qs
Qs grows with energy (1/x), A [ ]
GLR-MQ
Color Glass CondensateColor Glass Condensate
DPG: high pDPG: high ptt, leading twist, DLA DGLAP, leading twist, DLA DGLAP CQF, anomalous dimension, leading twist, BFKLCQF, anomalous dimension, leading twist, BFKL CGC: saturation region, all twist, JIMWLKCGC: saturation region, all twist, JIMWLK
Probing the CGCProbing the CGC Deep Inelastic Scattering: ep(A) ---> eXDeep Inelastic Scattering: ep(A) ---> eX
StructureStructure functionsfunctions: F: F22, F, FLL Particle productionParticle production
Nucleus - Nucleus CollisionsNucleus - Nucleus Collisions Initial conditions (number and energy density)Initial conditions (number and energy density) MultiplicitiesMultiplicities CGC + Hydro (see T. Hirano’s talk)CGC + Hydro (see T. Hirano’s talk)
Proton (Deuteron) - Nucleus CollisionsProton (Deuteron) - Nucleus Collisions MultiplicitiesMultiplicities Single Particle productionSingle Particle production
HadronsHadrons DileptonsDileptons PhotonsPhotons
Two particle productionTwo particle production Hadron-photon correlationsHadron-photon correlations Hadron-hadron correlationsHadron-hadron correlations
FF22 from NMC, E665,… from NMC, E665,… Low QLow Q22 ( < 1-2 GeV ( < 1-2 GeV22 ) at small x ( < 0.01) ) at small x ( < 0.01) Light vs. heavy nucleiLight vs. heavy nuclei
CGC: scaling [no separate dependence on x, QCGC: scaling [no separate dependence on x, Q22, but on , but on QQ22/Q/Q22
ss(x)](x)] A dependence ? (figs. from Freund et al. and Armesto et al.) A dependence ? (figs. from Freund et al. and Armesto et al.)
Particle production in dA: hadronsParticle production in dA: hadrons Forward rapidity: Forward rapidity: phase space in xphase space in xbjbj opens up opens up
Small xSmall xbjbj in nuclei (gluons) in nuclei (gluons) Large xLarge xbjbj in deuteron (quarks and gluons) in deuteron (quarks and gluons)
J. J-M.,Nucl.-th/0402080 KKT, hep-ph/0405045
Particle production in dA: dileptonsParticle production in dA: dileptons Cleaner probeCleaner probe No hadronizationNo hadronization Low ratesLow rates