hydrodynamic models of heavy- i on collisions
DESCRIPTION
Hydrodynamic Models of Heavy- I on Collisions. Tetsufumi Hirano RIKEN BNL Research Center. Parallel Talks Based on Hydro. Jan. 13 H. Niemi , Photon production from non-equilibrium QGP in heavy-ion collisions M. Csanad , Indication for quark deconfinement and - PowerPoint PPT PresentationTRANSCRIPT
Hydrodynamic Hydrodynamic Models of Heavy-Models of Heavy-
IIon Collisionson Collisions
Tetsufumi HiranoTetsufumi Hirano
RIKEN BNL Research RIKEN BNL Research CenterCenter
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 22
Parallel Talks Based on Parallel Talks Based on HydroHydroJan. 13Jan. 13
•H. NiemiH. Niemi, , Photon production from non-equilibriumPhoton production from non-equilibrium QGP in heavy-ion collisionsQGP in heavy-ion collisions•M. CsanadM. Csanad, Indication for quark deconfinement and, Indication for quark deconfinement and evidence for a Hubble flow in Au+Au collisions at RHICevidence for a Hubble flow in Au+Au collisions at RHIC
Jan. 15Jan. 15•Y. NaraY. Nara, , CGC, hydrodynamics and the partonCGC, hydrodynamics and the parton energy lossenergy loss•E. ShuryakE. Shuryak, , Why does the QGP behaves liWhy does the QGP behaves likkee a perfect fluid?a perfect fluid?•U. HeinzU. Heinz, , Rapidity dependence of momentumRapidity dependence of momentum anisotropiesanisotropies in nuclear collisionsin nuclear collisions•D. TeaneyD. Teaney, , Viscosity and thermalizationViscosity and thermalization
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OutlineOutline1.1. Why hydrodynamics?Why hydrodynamics?
2.2. How hydrodynamics works at RHICHow hydrodynamics works at RHIC
3.3. Hybrid models based on Hybrid models based on hydrodynamicshydrodynamics
– Information of the insideInformation of the inside (jet quenching , EM probe)(jet quenching , EM probe)– Improvement of initial stageImprovement of initial stage
4.4. Improvement of ideal hydro Improvement of ideal hydro (viscosity)(viscosity)
5.5. SummarySummary
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 44
1. Why Hydrodynamics?1. Why Hydrodynamics?Static•EoS from Lattice QCD•Finite T, field theory•Critical phenomena•Chiral property of hadron
Dynamic Phenomena in HIC•Expansion, Flow•Space-time evolution of thermodynamic variables
Once we accept localthermalization ansatz,life becomes very easy.
Caveat: Thermalization in HIC is a tough problem like building
the Golden Gate Bridge!
Energy-momentum:
Conserved number:
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 55
1. Why Hydrodynamics 1. Why Hydrodynamics (contd.)(contd.)
A full 3D hydrodynamic simulation with a CGC initial conditionTalk by Y.Nara
Space-time evolution of energy density in sqrt(sNN)=200 GeV Au+Au collision at b=7.2fm
Animation is here in the presentation.If you need, please ask me ([email protected]).
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 66
Hydrodynamics provides us a very intuitive
and simple description of relativistic heavy ion collisions.
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 77
OutlineOutline1.1. Why hydrodynamics?Why hydrodynamics?
2.2. How hydrodynamics works at RHICHow hydrodynamics works at RHIC
3.3. Hybrid models based on Hybrid models based on hydrodynamicshydrodynamics
– Information of the insideInformation of the inside (jet quenching , EM probe)(jet quenching , EM probe)– Improvement of initial stageImprovement of initial stage
4.4. Improvement of ideal hydro Improvement of ideal hydro (viscosity)(viscosity)
5.5. SummarySummary
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 88:P.Kolb(’03), talk by A.Poskanzer
2. How Hydrodynamics 2. How Hydrodynamics Works at RHICWorks at RHIC
Elliptic flow (J.-Y.Ollitrault (’92))Elliptic flow (J.-Y.Ollitrault (’92))How does the system respond to initial spatial anisotropy?How does the system respond to initial spatial anisotropy?
A.Poskanzer & S.Voloshin (’98)
Dense or dilute?Dense or dilute?If dense, thermalization?If dense, thermalization?
If thermalized, EoS?If thermalized, EoS?
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Elliptic Flow of Charged Elliptic Flow of Charged ParticlesParticles
T.H.(’01)
P.Huovinen(’03)
P.Kolb et al.(’01)
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Roughly speaking,ideal hydro gives a good description
For improvement of models, talk by U.Heinz
Roughly speaking,ideal hydro gives a good description
For improvement of models, talk by U.Heinz
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 1111
More on Elliptic FlowMore on Elliptic Flow
See recent excellent reviews, P.Huovinen (QM2002) , nucl-th/0305064; P.Kolb and U.Heinz, nucl-th/0305084; E.Shuryak, hep-ph/0312227, today’s talk.
Hydro: P.Kolb et al.(’99)(Note: Hydro+RQMD
gives a better description.D.Teaney et al.(’01))
STAR, PRC66(’02)034904
Hydro: P.Huovinen et al.(’01)
PHENIX, PRL91(’03)182301.
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 1212
What’s next?What’s next?
Ideal hydro seems to give Ideal hydro seems to give aa
good description at RHICgood description at RHIC
1.1. Making the most use of hydroMaking the most use of hydromodels to study the RHIC physicsmodels to study the RHIC physics
2.2. Checking how robust theChecking how robust thecurrent results are whencurrent results are when
hydro models are improvedhydro models are improved
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 1313
OutlineOutline1.1. Why hydrodynamics?Why hydrodynamics?
2.2. How hydrodynamics works at RHICHow hydrodynamics works at RHIC
3.3. Hybrid models based on Hybrid models based on hydrodynamicshydrodynamics
– Information inside fluidsInformation inside fluids (jet quenching , EM probe)(jet quenching , EM probe)– Improvement of initial stageImprovement of initial stage
4.4. Improvement of ideal hydro (viscosity)Improvement of ideal hydro (viscosity)
5.5. SummarySummary
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3.1 Information inside 3.1 Information inside fluidsfluids
Jet quenching isJet quenching is a manifestationa manifestation
of interaction betweenof interaction betweenmattermatter and partons and partons
(Talks by G.Moore and I.Vitev)(Talks by G.Moore and I.Vitev)
For quantitative analysis,For quantitative analysis,the information aboutthe information about
the space-time evolutionthe space-time evolutionof matterof matter
is indispensable!is indispensable!
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3.1.1 Hydro as a Tool to 3.1.1 Hydro as a Tool to Analyze Analyze Jet QuenchingJet QuenchingJet quenching analysis takingJet quenching analysis taking
account of (2+1)D hydro resultsaccount of (2+1)D hydro results (M.Gyulassy et al.(’02))(M.Gyulassy et al.(’02))
Hydro+Jet modelHydro+Jet model (T.H. & Y.Nara (’02))(T.H. & Y.Nara (’02))
Parton density Parton density ((xx) taken) taken from full 3D hydro simulationsfrom full 3D hydro simulations
GLV 1GLV 1stst order formula (M.Gyulassy et al.(’00)) order formula (M.Gyulassy et al.(’00))
Movie and data ofMovie and data of ((xx) ) are available atare available athttp://quark.phy.bnl.gov/~hirano/http://quark.phy.bnl.gov/~hirano/
Animation is here inthe presentation.
If you need, please ask [email protected]
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Interplay between Soft Interplay between Soft and Hardand Hard
NSOFT~NHARD
ppTT
(1/
(1/ ppTT)
()(dNdN
// dpdpTT))
HydrodynamicHydrodynamicafterburnerafterburner
JetJetquenchingquenching
Interesting regionIntermediate pT
(2<pT<3.5 GeV/c)Pion hard, Proton soft
It’s the veryheavy ion physics!
T.H & Y.Nara(’03)
Crossing pCrossing pTT moves movestoward high ptoward high pTT
softhard
Au+Au at b=2 fm
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 1717
Consequense from hadron Consequense from hadron species dependent pspecies dependent pT,crossT,cross
Hydro+Jet
Talk by R.FriesTalk by R.Fries
Recombination+Fragmentation
RAARAA Particle ratioParticle ratio
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 1818
“Scaling v2”Interplay between soft and hard?
Recombination mechanism?
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 1919
Thermal photon is a penetrating probe of QGP (E.Shuryak(’78))
3.1.2 Hydro as a Tool to 3.1.2 Hydro as a Tool to Analyze Analyze Electromagnetic Electromagnetic RadiationRadiation
T, u
• Production rateProduction rate (Number per unit space-time volume)(Number per unit space-time volume)
• Invariant spectrum of photonsInvariant spectrum of photons
H.A.Weldon (’83), L.McLerran & T.Toimela (’84)C.Gale & J.Kapusta (’91)Talk by G.Moore
D.K.Srivastava & B.Sinha(’94), J.Sollfrank et al.(’97),J.Alam et al.(’01) and a lot of work
Importance of temperature profileImportance of temperature profile
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 2020
Chemical Non-Chemical Non-EquilibriumEquilibriumQGP phaseQGP phase ““Gluon Plasma (GP)” Gluon Plasma (GP)”
QGPQGP
Hadron Hadron phasephase
Chemical freezeoutChemical freezeout
Talk by H.Niemi
Hydro + rate eq.Hydro + rate eq.Smaller d.o.f. Smaller d.o.f. Larger Larger
initial initial TT
T.H. & K.Tsuda(’02)
Hydro( )Hydro( )Overpopulation of Overpopulation of resonance resonance Rapid Rapid
cooling cooling
T.S.Biro et al.(’93), D.K.Srivastava et al.(’97),A.K.Chaudhuri(’00), D.M.Elliott & D.Rischke(’00)
N.Arbex et al.(’01), T.H. & K.Tsuda(’02),D.Teaney(’02), P.Kolb & R.Rapp(’03)
Talk by H.Niemi
QGP phaseQGP phase Hadron phaseHadron phase
100
200
300
400
500
600
700
800
Tem
pera
ture
(M
eV
)
0
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Novel Temperature Novel Temperature EvolutionEvolution
Caveat: one has to take account offugacity in calculating EMspectra.
•QGP phase: <1•Hadron phase: >1
Compensation betweenT and ? Talk by H.Niemiproper time
Tc
tem
pera
ture
chemical non-eq.
chemical eq.
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3.2 Improvement of Initial 3.2 Improvement of Initial ConditionCondition -Toward an unified model -Toward an unified model in HIC-in HIC-
GroupGroup HydroHydro Initial conditionInitial conditionM.Gyulassy et M.Gyulassy et al.al.
SHASTA (2+1D, SHASTA (2+1D, Bjorken)Bjorken)
HIJING, event-by-eventHIJING, event-by-event
C.Nonaka et C.Nonaka et al.al.
Lagrangian hydro (full Lagrangian hydro (full 3D)3D)
URASiMA, event averageURASiMA, event average
B.Schlei et al.B.Schlei et al. HYLANDER (2+1D)HYLANDER (2+1D) VNI, event averageVNI, event average
C.E.Aguiar et C.E.Aguiar et al.al.
SPheRIO (full 3D)SPheRIO (full 3D) NeXus, event-by-eventNeXus, event-by-event
L.P.Csernai et L.P.Csernai et al.al.
Particle-in-cell (full Particle-in-cell (full 3D)3D)
String ropes, flux tubes, String ropes, flux tubes, classical YMclassical YM
K.Eskola et al.K.Eskola et al. SHASTA (2+1D, SHASTA (2+1D, Bjorken)Bjorken)
pQCD + final state pQCD + final state saturationsaturation
T.H. & Y.NaraT.H. & Y.Nara coordinate (full coordinate (full 3D)3D)
CGC, CGC, ((kkTT22,,xx) a la Kharzeev ) a la Kharzeev
& Levin& Levin
…… …… ……
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3.2.1 SPheRIO*3.2.1 SPheRIO*Main features:Main features:• ““Particle” method (a kind of Lagrangian hydro)Particle” method (a kind of Lagrangian hydro)• Numerical cost cheaper than conventional finite Numerical cost cheaper than conventional finite
grids method (Even in 3+1 D, any geometry)grids method (Even in 3+1 D, any geometry)• Event-by-event physicsEvent-by-event physics ( (NeXusNeXus + +
SPheRIO=NeXSPheRIO) SPheRIO=NeXSPheRIO) (NeXus: parton based Gribov-Regge theory)(NeXus: parton based Gribov-Regge theory)
*Smoothed Particle hydrodynamical evolution of Relativistic heavy IOn collisions (Sao Paulo & Rio de Janeiro)
C.E.Aguiar, R.Andrade, F.Grassi, Y.Hama,T.Kodama, T.Osada, O.Socolowski Jr….Poster by F.Grassi
Energy Energy densitydensityof single of single
eventeventSpectrafrom
Energy Energy densitydensityof single of single
eventevent Spectrafrom
Conventional approachSPheRIO
Similar approach based on HIJING: M.Gyulassy et al.(’97)
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Initial Conditions in Initial Conditions in NeXSPheRIONeXSPheRIO
Single event (b=0fm)Single event (b=0fm) Average over 30 events (b=0fm)Average over 30 events (b=0fm)
Energy density in the transverse plane (z=0)Energy density in the transverse plane (z=0)
Bumpy!
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Results from Results from NeXSPheRIONeXSPheRIOPb+Pb 17.3A GeV
Multiplicity is reduced by ~10%!
:(event average)
Effect of initial energy densityfluctuation (simple EoS case):
Negative!
pT slope is not affected largely. v2(pT) and its fluctuation?
Now the hydro simulation becomes
close to experimental situations
like event-generators!
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3.2.2 CGC+Hydro+Jet 3.2.2 CGC+Hydro+Jet ModelModel T.H. & Y.Nara
Talk by Y.Nara
Dense MediumDense Medium
These three physics closely related with each other!
Talk by J.Jalilian-Marian
Talk by I.Vitev
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CGC+Hydro+Jet Model CGC+Hydro+Jet Model (contd.)(contd.)
Full 3Dhydro evolution
pQCDpQCDpartonpartondilutedilute
timetimemom
en
tum
scale
mom
en
tum
scale
ggg
22
CGCCGCsmall xsmall xdensedense
collinearfactorization
kT factorization
Partonenergy loss
Initial condition of
energy density from
CGCAu+Au
200AGeVb=7.2fm, =0.6fm
transversetransverse longitudinallongitudinal
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Results from Results from CGC+hydro+jetCGC+hydro+jet
Au+Au sqrt(sNN) = 200 GeV
For details, talk by Y.Nara
CGC initial conditionworks very well!
(Energy, rapidity, centralitydependences)
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 3030
OutlineOutline1.1. Why hydrodynamics?Why hydrodynamics?
2.2. How hydrodynamics works at RHICHow hydrodynamics works at RHIC
3.3. Hybrid models based on Hybrid models based on hydrodynamicshydrodynamics
– Information of the insideInformation of the inside (jet quenching , EM probe)(jet quenching , EM probe)– Improvement of initial stageImprovement of initial stage
4.4. Improvement of ideal hydro (viscosity)Improvement of ideal hydro (viscosity)
5.5. SummarySummary
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 3131
4. Viscosity4. ViscosityChange not only the equations of motionbut the local thermal distribution function A.Dumitru(’02), D.Teaney(’03)
• Blast wave model + dist. fn. with viscous correction
Talks by E.Shuryak and D.Teaney
1st order correction to dist. fn.:
:Sound attenuation length
:Tensor part of thermodynamic force
Reynolds number in Bjorken flow
Nearly ideal hydro !? D.Teaney(’03)
Tetsufumi Hirano (RBRC)Tetsufumi Hirano (RBRC) 3232
Break Down of Naive Break Down of Naive Navier-Stokes Eq. and a Navier-Stokes Eq. and a Relaxation MethodRelaxation Method•Non-relativistic case (Based on discussion by Cattaneo (1948))
0: Fourier’s law
: “relaxation time”
Parabolic equation (heat equation)ACAUSAL!!
Finite Hyperbolic equation (telegraph equation)
Balance eq.:
Constitutive eq.:
Talk by D.TeaneySee also, A.Muronga (’02)
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5. Summary5. Summary
• Open our mind Open our mind !! Hydrodynamics Hydrodynamics can be used even can be used even for “high pfor “high pTT physics in HIC”.physics in HIC”.– Jet tomographyJet tomography– EM probeEM probe– (J/(J/ suppression) suppression)– ……
• Keep in mind Keep in mind !! How robust is the How robust is the
current agreement current agreement of hydro?:of hydro?:– Chemical non-eq.?Chemical non-eq.?– Initial fluctuation?Initial fluctuation?– Viscosity?Viscosity?– Thermalization?Thermalization?– EoS?EoS?– (Freeze-out?)(Freeze-out?)
Hydrodynamics is one of the valuable tools at RHIC energies