Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä1 Prospects on identified particle correlation in ALICE Levente Molnar INFN-Bari, KFKI-RMKI

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä2 RHIC results on particle ratios PHENIX, PRL 91, Enhanced baryon/meson ratio in 200 GeV Au+Au collisions (Anti-)proton-pion ratio above fragmentation,... Limited intermediate p T window STAR, PRL 97,152301

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä3 Soft and hard interplay at RHIC Particle spectra, R CP and particle ratios are “well” described by soft and hard component models: Recombination + fragmentation Hydro + jets Hydro + pQCD Soft + quenched Fries,Muller, PRL , PRCC

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä4 Soft and hard interplay at LHC The relative soft + hard contribution changes at higher energies: Recombination predictions… How well do we know the hard component? Measure p+p baseline … Fries R. J.,Müller B. Eur. J. Phys. C 34 S279 LHC: Pb+Pb R.Hwa, PRL97,04230

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä5 Contribution of quark and gluon jets in p+p Good description at 200GeV STAR, PLB 637,161 Λ K0K0 S. Albino et al., NPB 597,337 Missing higher energy: 630 GeV PID in jet correlations

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä6 Particle correlations at RHIC STAR, nucl-ex/ Two particle correlations in the intermediate p T region with trigger particle (4 <p T trig <6 GeV/c ) exhibit: broadening of away side correlation (0.15<p T assoc <4.0 GeV/c) suppression of high p T particles in central Au+Au collisions (2 GeV/c <p T assoc <p T trig) F.Wang,NPA783,157, L.M. nucl-ex/ Mid-rapidity Forward-rapidity Mid-rapidity STAR, 91 (2003)

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä7 Particle correlations at RHIC II. Presence of long range ∆η correlations Extends to forward rapidities? Particle composition of “bulk” and “ridge”, ongoing effort at RHIC STAR, nucl-ex/ F.Wang,NPA783,157, L.M. nucl-ex/ J.Putschke, QM’06 Au+Au 200GeV 0-10%

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä8 Particle correlations at RHIC III. STAR, nucl-ex/ Au+Au Central 0-12% Triggered J.Ulery, IWCF’06 N.Ajitanand IWCF’06 Identified particles in the cone region, similarly to “ridge” measurements M.Ploskon

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä9 ITS Low p t tracking Vertexing ITS Low p t tracking Vertexing TPC Tracking, dEdx TPC Tracking, dEdx TRD Electron ID TRD Electron ID TOF PID TOF PID HMPID PID high p t HMPID PID high p t PHOS ,  0 PHOS ,  0 MUON  -pairs MUON  -pairs PMD  multiplicity PMD  multiplicity V0, T0 Trigger + multiplicity ACORDE cosmics FMD ch multiplicity FMD ch multiplicity EM Calorimeter The ALICE detector First run setup: ITS, TPC, MUON HMPID 10-15% TRD 50% ToF

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä10 Low magnetic field ( T) Wide momentum range (tracking): ~ 100 MeV up to >100 GeV Strong PID capabilities in the central region (|η|<0.9) Particle identification in ALICE Direct hadron PID: (p, K, p) up to ~ 5 GeV, rdEdx ~ 50 GeV/c Photons, Leptons Topological PID up to ~ 20 GeV/c 3  2  EMCAL ALICE PPR II, JPG 32,1295

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä11 Multiplicity at the Tevatron and LHC W.D.Walker PRD 69, Increasing cms. energy, broken KNO scaling NchNch 900GeV 14TeV 5.5TeV 2.2TeV Probability for an event to have larger than N ch multiplicity (|  |<0.9) T.Nayak, QM’06 At LHC: further multiplicity reach study multi-parton interactions dedicated high multiplicity trigger (?)

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä12 Soft and hard events a la CDF EMCAL+tracking (|η|<1.2) In a cone R = 0.7 define (EMCAL + tracking) Soft events: –no cluster with E T > 1.1 GeV Hard events: –E T seed >= 1.0 GeV or track with p T >= 0.7 GeV/c –E T adj. > 0.1 GeV or track with p T > 0.4 GeV/c CDF, PRD65,

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä13 Soft and hard events a la CDF II. (CDF) conclusions: Momentum distribution of “soft” events depends on Nch not on √s scales with √s CDF, PRD65,

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä14 Soft and hard events a la CDF III. CDF, hep-ex/ The soft production of Λ 0 and K 0 S similar

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä15 High multiplicity trigger D.Elia ITS/SPD HMPID Enhance high multiplicity events Limited HMPID : PID acceptance: fastOR trigger of SPD layers LHC commissioning …

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä16 Identified particles at Tevatron E735, PRD48,984 B. Hippolyte, EPJ. C49: ,2007STAR, nucl-ex/ Mapping identified particles in p T, Nch at each possible energies.

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä17 Particle correlations at ALICE Full jet reconstruction possible event by event: E T min ~ 40 GeV jet fragments: p T ~ 2GeV/c RHIC results: statistical approach LHC: enhanced yield of leading hadrons but increase in comb. background How does it look like?

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä18 Charged hadron correlations in ALICE Significant away side at low p T assoc in 5.5TeV PbPb. Appelshäuser H and Ploskon M 2005 ALICE-INT

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä19 Particle correlations at ALICE Full jet reconstruction possible event by event: E T min ~ 40 GeV jet fragments: p T ~ 2GeV/c RHIC results: statistical approach LHC: enhanced yield of leading hadrons but increase in comb. background Focus on the near side: full PID for leading and associated particle(s) ITS+TPC+ToF+TRD (full azimuth, |η|<0.9) HMPID (57.61º in azimuth, |η|<0.6, track-by-track PID)

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä20 PID Particle correlations at ALICE Leading particle correlations: trigger bias, determination of E jet, swing of away side parton, … γ – PID correlations: measures E jet, fix direction low p T limit Utilize ALICE geometry → PID PHOS module opposite to HMPID + ITS/TPC/TRD/ToF Adjacent to EMCAL+PHOS map out the underlying events PID of leading and assoc. particles: dial q/g jets? Measure resonance particles

Levente Molnar, INFN-Bari, KFKI-RMKIMarch, 2007, Jyväskylä21 Summary RHIC results show a “complicated” intermediate p T region in HI collisions p+p measurement at the same cms energy are essential baseline to interpret HI collision PID (γ/h) correlations could provide more refined tools First data in ~ 8 months …