Milestones at the PHENIX experiment at RHIC Máté Csanád, Eötvös University Budapest for the PHENIX collaboration Milestone #1: High p t suppressionMilestone

MilestonesMilestones atat the PHENIX the PHENIX experiment at RHICexperiment at RHIC

Máté Csanád, Eötvös University BudapestMáté Csanád, Eötvös University Budapestfor the for the PHENIX collaborationPHENIX collaboration

• Milestone #1: High pMilestone #1: High ptt suppression suppression• Milestone #2: The erfect fluid of Milestone #2: The erfect fluid of

quarksquarks• Heavy flavourHeavy flavour• Chiral dynamicsChiral dynamics• Further resultsFurther results

M. Csanád for PHENIX, Hadron 2007

2/14

BNL FacilityBNL Facility

• protons: Linac protons: Linac Booster Booster AGS AGS RHIC RHIC

• ions: Tandems ions: Tandems Booster Booster AGS AGS RHIC RHIC

STAR

PHENIX

PHOBOSBRAHMS

RHIC, lenght: 3.83 km


3/14

The Plan circa 2000The Plan circa 2000• Use RHIC’s unprecedented capabilitiesUse RHIC’s unprecedented capabilities

– Large √sLarge √s →→• Access to reliable pQCD probesAccess to reliable pQCD probes• Clear separation of valence baryon number and glueClear separation of valence baryon number and glue• To provide definitive experimental evidence for/against To provide definitive experimental evidence for/against

QQuark Gluon Plasma (QGP)uark Gluon Plasma (QGP)

– Polarized p+p collisionsPolarized p+p collisions → proton spin structure! → proton spin structure!

• Two small detectors, two large detectorsTwo small detectors, two large detectors– Complementary Complementary && overlapping capabilities overlapping capabilities – Small detectorsSmall detectors: BRAHMS and PHOBOS: BRAHMS and PHOBOS

• 3-5 year lifetime3-5 year lifetime

– Large detectorsLarge detectors: STAR and PHENIX: STAR and PHENIX• Major capital investmentsMajor capital investments• Longer lifetimesLonger lifetimes• Potential for upgrades in response to discoveriesPotential for upgrades in response to discoveries


4/14

Since then …Since then …• Accelerator complexAccelerator complex

– 22 GeV (Au, Cu, p22 GeV (Au, Cu, p))– 56 GeV (Au)56 GeV (Au)– 62 GeV (Au,62 GeV (Au, Cu, pCu, p– 130 GeV (Au)130 GeV (Au)– 200 GeV (Au, Cu, d, p200 GeV (Au, Cu, d, p))– 410 GeV (p410 GeV (p))– 500 GeV (p500 GeV (p))

• ScienceScience– 100 publications in Phys. Rev. Letters100 publications in Phys. Rev. Letters– Major discoveriesMajor discoveries

• Future: RHIC-II and eRHICFuture: RHIC-II and eRHIC– Key science questions identifiedKey science questions identified– Accelerator and experimental upgrade programAccelerator and experimental upgrade program

underwayunderway


5/14

Event geometryEvent geometry• In these complicated events, we have a In these complicated events, we have a

posteriori control over the event geometry:posteriori control over the event geometry:– Degree of overlapDegree of overlap, number of participants (N, number of participants (Npartpart))– Orientation with respect to overlap (Reaction Plane)Orientation with respect to overlap (Reaction Plane)

Central Central Au+AuAu+Au

NNpartpart~300~300

Reaction Reaction

PlanePlane

Peripheral Peripheral Au+AuAu+Au

NNpartpart~~5500

d+Ad+Auu

p+p+pp


6/14

PHENIXPHENIX capabilities capabilities• Central armCentral arm, , |y|<0.35|y|<0.35, , Δφ=Δφ=ππ

– Tracking: DC, PC and TECTracking: DC, PC and TEC– Calorimetry: Calorimetry: PbGl and PbSc PbGl and PbSc ((EMCal)EMCal)– Particle ID: Particle ID: RICH RICH and and TTOFOF

• Muon armsMuon arms, 1.2<, 1.2<|y|<|y|<2.4, 2.4, ΔφΔφ=2=2ππ– TrackingTracking: : 3 muon tracker3 muon tracker– IIdentificationdentification 5 detection planes5 detection planes– Front absorber to stop hadronsFront absorber to stop hadrons

• Global detectorGlobal detectorss– BBC, MVDBBC, MVD– Centrality, vertex, reaction planeCentrality, vertex, reaction plane

• PhysicsPhysics– CCharged hadrons ( harged hadrons ( ππ±±, K, K±±, etc.), etc.)– PPhotonshotons,, direct or decay (direct or decay (→→ ηη , , ππ00))– LiLight mesonght mesonss φ, ω φ, ω and and η η– SSingle leptons → heavy flavoringle leptons → heavy flavor– DDi-leptons → heavy flavor, J/Ψi-leptons → heavy flavor, J/Ψ


7/14

Detector upgradesDetector upgrades• 20062006

– AerogelAerogel– Hadron-Blind DetectorHadron-Blind Detector– Reaction Plane DetectorReaction Plane Detector– Time Of Flight WestTime Of Flight West– Muon Piston CalorimeterMuon Piston Calorimeter

• 2007 – 20092007 – 2009– Silicon Vertex TrackerSilicon Vertex Tracker

• 2008 – 20112008 – 2011– Forward Vertex TrackerForward Vertex Tracker– Nose Cone CalorimeterNose Cone Calorimeter


8/14

The PHENIX CollaborationThe PHENIX Collaboration


9/14

A PHENIX eventA PHENIX event


10/14

Run-7 Run-7 Au+Au: Au+Au: major major success!success!

+ Upgrades: RXNP, TOF-W, MPC, HBD+ Upgrades: RXNP, TOF-W, MPC, HBD


11/14

Milestone #1: jet Milestone #1: jet suppressionsuppression

• Nuclear modification factor: Nuclear modification factor:

Measured in Au+Au, reference: p+pMeasured in Au+Au, reference: p+p

• High pHigh ptt particles suppressed! particles suppressed!

• Counter-probe: d+Au → Medium effect (not color gl. Counter-probe: d+Au → Medium effect (not color gl. cond.)cond.)

• 2 PRL covers2 PRL coversAu+AuAu+Au

d+Aud+Au

ABAB

binary AB pp

Yield1R

N Yield

AB

ABbinary AB pp

Yield1R

N Yield


12/14

Systematic Systematic ssuppressionuppression of of ππ00

• Appr. cAppr. constanonstant t for pfor pTT > 4 GeV/c for all centralities > 4 GeV/c for all centralities

– PQM (Loizides) hep-ph/0608133:PQM (Loizides) hep-ph/0608133: 6 ≤ q6 ≤ q^̂ ≤ 24 GeV2/fm ≤ 24 GeV2/fm

– GLV (Vitev) hep-ph/0603010:GLV (Vitev) hep-ph/0603010: 1000 ≤ dN1000 ≤ dNgg/dy ≤ 2000/dy ≤ 2000

– WHDG (Horowitz) nucl-th/0512076:WHDG (Horowitz) nucl-th/0512076: 600 ≤ dN600 ≤ dNgg/dy ≤ 1600/dy ≤ 1600

Su

pp

ressed

Su

pp

ressed

En

han

ced

En

han

ced

Phys.Rev.C76:034904,2007


13/14

Photons shine, Pions don’tPhotons shine, Pions don’t

• No direct photon suppression until 14 GeVNo direct photon suppression until 14 GeV– DDecreasing trendecreasing trend at >14 GeV at >14 GeV– Isospin, shadowing and energy loss, see F. Arleo, Isospin, shadowing and energy loss, see F. Arleo, hep-ph/0601075hep-ph/0601075

• SSuppressionuppression of of ππ00 stays nearly constant stays nearly constant up to 20 up to 20 GeV/cGeV/c

• Direct photons are not inhibited by hot/dense mediumDirect photons are not inhibited by hot/dense medium


14/14

J/J/ΨΨ suppressionsuppression in Au+Au in Au+Au

• Even J/ Even J/ ΨΨ suppressed! suppressed!– beyond extrapolations from beyond extrapolations from

cold nuclear matter effectscold nuclear matter effects

• RRAAAA ~ 0.3 for central ~ 0.3 for central collisionscollisions

• Larger suppression at |Larger suppression at |y|>1.2y|>1.2

Phys. Rev. Lett. 98, 232001 (2007)


15/14

Milestone #2: The perfect fluidMilestone #2: The perfect fluid

• Momentum distribution axially Momentum distribution axially

symmetric?symmetric?

• Azimuthal angle w.r.t. reaction placeAzimuthal angle w.r.t. reaction place

• Elliptic flow vElliptic flow v22: azimuthal asymmetry: azimuthal asymmetry– Measures collective behaviorMeasures collective behavior– Zero vZero v22 for a rare gas for a rare gas

– Hydrodynamic behavior: vHydrodynamic behavior: v22 > 0 > 0 nucl-th/0512078nucl-th/0512078

ΔΔφφReactio

n

Reaction

planeplane

12 N ( )

v cos(2 )

1

2 N ( )v cos(2 )


16/14

Top Story 2005Top Story 2005According to the American Institut of According to the American Institut of Physics the top physics story in 2005 Physics the top physics story in 2005

was the discovery of the perfect liquidwas the discovery of the perfect liquid


17/14

Perfect fluid of quarksPerfect fluid of quarks

• Relevant variable: not pRelevant variable: not ptt, but transverse kinetic energ , but transverse kinetic energ KEKEtt

• Elliptic flow scales with number of constituent quarks!Elliptic flow scales with number of constituent quarks!• Degrees of freedom: quarks?Degrees of freedom: quarks?

PHENIX Collaboration, Phys.Rev.Letters 98:162301, 2007PHENIX Collaboration, Phys.Rev.Letters 98:162301, 2007

2 2( ) ( )

hadron quarkT T

hadron hadron quark quarkT T

KE nKE

v KE nv KE

2 2( ) ( )

hadron quarkT T

hadron hadron quark quarkT T

KE nKE

v KE nv KE


18/14

Even d, D and Even d, D and ΦΦ flow flow• Strange and even charm quarks participate in the flowStrange and even charm quarks participate in the flow• vv22 for the φ follows that of other mesons for the φ follows that of other mesons• vv22 for the d follows thatof other barions for the d follows thatof other barions• vv22 for the D follows that of other mesons for the D follows that of other mesons

nucl-ex/0703024


19/14

Phys. Rev. Lett. 98, 172301 (2007)

Heavy flavourHeavy flavour• Electrons from Electrons from

heavy flavour heavy flavour measuredmeasured

• Even heavy flavour Even heavy flavour is suppressedis suppressed

• Even heavy flavour Even heavy flavour flowsflows

• SStrong coupling of trong coupling of charmcharm+bottom+bottom to to the mediumthe medium

• SSmall mall charmcharm+bottom+bottom relaxation time in relaxation time in medium and small medium and small viscosityviscosity


20/14

Signal of chiral dynamicsSignal of chiral dynamics

•SSignificant excess at ignificant excess at mmeeee<< 1GeV/c 1GeV/c in in Au+AAu+Auu

•Not in p+pNot in p+p

•Not in peripheral Au+AuNot in peripheral Au+Au

•Present in central Au+AuPresent in central Au+Au

•Enhancement of Enhancement of ηη’, ’, ηη, , ωω??

arXiv:0706.3034 [nucl-ex]


21/14

Restoration of chiral Restoration of chiral symmetry?symmetry?

• Prediction: mass of Prediction: mass of ’ decreases in hot ’ decreases in hot and dense matter due to Uand dense matter due to UAA(1) symmetry (1) symmetry restorationrestoration

• Idea: measure Idea: measure (m(mtt) at low momenta!) at low momenta!Hot and dense matter:Hot and dense matter:Modified Modified ’’ mass mass

Enhanced Enhanced ’’ production production

Decay:Decay:’’+++ + ++-- ((00++++++−−)+)+++++−−

with long lifetimewith long lifetimeAverage Average pptt: 138 MeV: 138 MeV

More non interacting More non interacting ’s at 138 MeV’s at 138 MeV

(m(mtt) measures fraction of ) measures fraction of

interacting interacting ’s’s

Hole in Hole in (m(mtt))

Hot and dense matter:Hot and dense matter:Modified Modified ’’ mass mass

Enhanced Enhanced ’’ production production

Decay:Decay:’’+++ + ++-- ((00++++++−−)+)+++++−−

with long lifetimewith long lifetimeAverage Average pptt: 138 MeV: 138 MeV

More non interacting More non interacting ’s at 138 MeV’s at 138 MeV

(m(mtt) measures fraction of ) measures fraction of

interacting interacting ’s’s

Hole in Hole in (m(mtt))

nucl-ex/nucl-ex/05090420509042

PHENIX PRELIMINARY


22/14

Three particle correlationsThree particle correlations

• Two angles:Two angles: ΔΦ ΔΦ and and ΔΔΘΘ• Simulations: jet deflection and Mach structuresSimulations: jet deflection and Mach structures• DataData: compatible with: compatible with Mach cone like structure Mach cone like structure

• UUnderlying vnderlying v22 contribution not subtracted contribution not subtracted yet yet


23/14

3D 3D two-pion two-pion source imagingsource imaging• A new technique A new technique

successfully appliedsuccessfully applied• Two-pion correlation Two-pion correlation

functions ↔ source functions ↔ source functionsfunctions

• Distribution of pair Distribution of pair separation measuredseparation measured

• Information on Information on hadronizationhadronization

• In LCMS: expected In LCMS: expected elongation in out (x) elongation in out (x) directiondirection

• Excess: elongation on the x Excess: elongation on the x and z axis; why?and z axis; why?

• Model-dependent answer: Model-dependent answer: Resonance decays and Resonance decays and ΔτΔτ=2fm/c=2fm/c PHENIX PRELIMINARY


24/14

Critical phenomenaCritical phenomena• Density correlations measuredDensity correlations measured

– Well described by Negative Binomial DistributionsWell described by Negative Binomial Distributions– Interpolating between Bose-Einstein and PoissonInterpolating between Bose-Einstein and Poisson

– Basic parameter k ↔ Basic parameter k ↔ ξξ ↔ susceptibility ↔ susceptibility χχωω=0=0~|T-T~|T-Tcc||-1-1

• Parameter Parameter ξξ monotonical in temperature monotonical in temperature• Not at the critical point!Not at the critical point!

• Local max. at NLocal max. at Npartpart≈90≈90

• Critical phenomenon?Critical phenomenon?in Landau-Ginzbergin Landau-Ginzberg

frameworkframework


25/14

Summary and conclusionsSummary and conclusions• High pHigh ptt hadrons suppressed hadrons suppressed

→ → strongly interacting matterstrongly interacting matter– Even J/Even J/ΨΨ and heavy flavour, photons not and heavy flavour, photons not

• Flow effects observed, quark number Flow effects observed, quark number scalingscaling

→ → perfect fluid of quarksperfect fluid of quarks– Scaling valid for Scaling valid for ππ, K, D, , K, D, φφ, p, d, p, d

– Even charm and bottom flowEven charm and bottom flow

• Details being exploredDetails being explored– Source geometrySource geometry

– Critical phenomenaCritical phenomena

Thank you for your Thank you for your attentionattention


27/14

System size dependence of System size dependence of ππ00

RRAAAA

RRAAAA is the same in Cu+Cu and Au+Au at equal N is the same in Cu+Cu and Au+Au at equal Npartpart


28/14

J/J/ΨΨ production in p+p collisions production in p+p collisions

• 10 times more statistics 10 times more statistics thanthan previous previous measurementmeasurement– better constraints on rapidity and pbetter constraints on rapidity and ptt spectrum spectrum– better reference for the nuclear modification factorbetter reference for the nuclear modification factor

Phys. Rev. Lett. 98, 232002 (2007)


29/14

J/Ψ RJ/Ψ RAAAA vs vs ppTT in Au+Au in Au+AuPhys. Rev. Lett. 98, 232001 (2007)

No significant No significant change of the change of the pptt distributions distributions with respect to with respect to p+p, but error p+p, but error bars are largebars are large


30/14

J/J/ΨΨ R RAAAA vs rapidity in Au+Au vs rapidity in Au+Au

0-20% 20-40%

40-60% 60-92%

Phys. Rev. Lett. 98, 232001 (2007) • PeripheralPeripheral::– no no

modification of modification of the rapidity the rapidity distribution distribution with respect to with respect to p+p collisionsp+p collisions

• Central: Central: – narrowing of narrowing of

the rapidity the rapidity distributiondistribution


31/14

ViscosityViscosity

• An AdS/CFT lower bound:An AdS/CFT lower bound:– hep-th/9711200, gr-qc/0602037, hep-th/9711200, gr-qc/0602037,

hep-th/0405231hep-th/0405231• MeasurementsMeasurements

– R. Lacey et al.,R. Lacey et al., nucl-ex/0609025nucl-ex/0609025

– H.-J. Drescher et al.,H.-J. Drescher et al., ararx:x:0704.35530704.3553

– S. GavinS. Gavin,, M. Abdel-Aziz, M. Abdel-Aziz, nucl-th/0606061nucl-th/0606061

– A. Adare et al.,A. Adare et al., n nucl-ex/0611018ucl-ex/0611018

(1.1 0.2 1.2)4s

(1.1 0.2 1.2)4s

(1.0 3.8)4s

(1.0 3.8)4s

(1.3 2.0)4s

(1.3 2.0)4s

(1.9 2.5)4s

(1.9 2.5)4s

4s

4s


32/14

• Perfect ≠ ideal!Perfect ≠ ideal!– Perfect: negligible viscosity and heat conductionPerfect: negligible viscosity and heat conduction– Ideal: incompressibleIdeal: incompressible

• ViViscosityscosity : measure of resistance to shear : measure of resistance to shear stressstress– Approx.:Approx.:

• Low viscosityLow viscosity High cross-sect. High cross-sect. Strong Strong couplingcoupling

• Important measure: kinematic viscosity Important measure: kinematic viscosity • AdS/CFT duality:AdS/CFT duality:

– hep-th/9711200, gr-qc/0602037, hep-th/9711200, gr-qc/0602037, hep-th/0405231hep-th/0405231

• Measurements:Measurements:– nucl-ex/0609025, arxiv:0704.3553,nucl-ex/0609025, arxiv:0704.3553,

nucl-th/0606061, nucl-ex/0611018nucl-th/0606061, nucl-ex/0611018

A perfect fluid?A perfect fluid?

(mom.density)×(mean free path)σ

pv (mom.density)×(mean free path)

σ

pv

(1.8 0.6 1.2)4s

(1.8 0.6 1.2)4s

4s

4s

s s


33/14

LLight mesons Right mesons RAAAA

ω in Au+Au@200 GeV, cent: 60-92% and 0-20%

• HighHigh p ptt suppression for suppression for φφ and ω,and ω, s similar to imilar to ππ and η and η

• RRdAdA also compatible with (equal to 1) also compatible with (equal to 1)

, p and π in Au+Au@200 GeV 0-10%


34/14

Comparison: Comparison: ρρ mass mass modificationmodification

R.Rapp, Phys.Lett. B 473 (2000)R.Rapp, Phys.Lett. B 473 (2000)R.Rapp, Phys.Rev.C 63 (2001)R.Rapp, Phys.Rev.C 63 (2001)R.Rapp, nucl/th/0204003R.Rapp, nucl/th/0204003

calculations for min calculations for min bias QGPbias QGP, , thermal thermal radiation includedradiation included

Broad range Broad range enhancement enhancement

150 < m150 < meeee < 750 < 750

MeVMeV3.4±0.2(stat.) 3.4±0.2(stat.)

±1.3(syst.)±1.3(syst.)±0.7(model)±0.7(model)

submitted to Phys. Rev. submitted to Phys. Rev. LettLett

arXiv:0706.3034arXiv:0706.3034


35/14

Mean pMean ptt22 vs N vs Npartpart

• <p<ptt22>>

– 0<p0<ptt<5<5 GeV/cGeV/c

• Constant vs Constant vs NNpartpart

– For Au+Au, For Au+Au, Cu+Cu, p+pCu+Cu, p+p


36/14

11stst milestone: new milestone: new phenomenonphenomenon

• Suppression of high pSuppression of high ptt particles: PHENIX result particles: PHENIX result on the cover of Physical Review Letterson the cover of Physical Review Letters

• Is this a medium effect?Is this a medium effect?


37/14

22ndnd: new type of matter: new type of matter

• The new phenomenon is not obserable in d+Au The new phenomenon is not obserable in d+Au

collisionscollisions

• Not the modification of the nucleusNot the modification of the nucleus

• Au+Au: it is a new type of matter!Au+Au: it is a new type of matter!


38/14

Proton spin structure via Proton spin structure via heavy flavorheavy flavor

• LLongitudinally ongitudinally polarized proton beamspolarized proton beams

• J/ΨJ/Ψ measured measured• Sensitive to PDFSensitive to PDF

proton

proton

gluon

gluonheavy fl.

QQggLL

BG

BGLLBG

inclLLJ

LL

YB

inclLL

axgxg

xgxg

fAfA

A

NRNNRN

PPA

)()(

)()(

1

1

2

2

1

1

/

Documents

Milestones at the PHENIX experiment at RHIC Máté Csanád, Eötvös University Budapest for the PHENIX collaboration Milestone #1: High p t suppressionMilestone