1 search for collective phenomena art poskanzer in honor of miklos gyulassy’s 60 th birthday 1995...
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Search for Collective Phenomena
Search for Collective Phenomena
Art Poskanzer
In honor of Miklos Gyulassy’s60th birthday
1995
Not a surprise party
History of the
Emphasizing Miklos’ Contributions
2
Same Topic 26 Years AgoSame Topic 26 Years Ago
Nuclear Physics AVolume 400, 23 May 1983, Pages 31-41
Copyright © 1983 Published by Elsevier B.V.
Nuclear collisions from AMeV to ATeV:From nuclear to quark matter
Miklos Gyulassy
Nuclear Science Division, Lawrence Berkeley Laboratory University of California,Berkeley, CA 94720 USA
Opening talk at Nucleus-Nucleus ‘82 at MSU:
Gyulassy 1983
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Collisions of Swiss WatchesCollisions of Swiss Watches
Poskanzer, CERN colloquium (1980)
general negative attitude
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Flowers Amongst the WeedsFlowers Amongst the WeedsAt the 2nd Heavy Ion Summer Study in 1974 Wladek Swiateckitalked about “Clearing the weeds and Getting to the heart of the matter”
In the 35 years since there have been a few flowers
Swiatecki 1983
to find a flower
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QM87 NordkirchenQM87 NordkirchenConcluding Remarks by Miklos Gyulassy
22 years ago, it was the most memorable talk I have ever heard
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Shock Waves - 1959Shock Waves - 1959
Annals of Physics 6, 1 (1959)
First prediction of collective flow at high energy
Angle depends on the speed of soundwhich depends on the Eq. of State
50 years ago
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Shock WavesShock Waves
W. Scheid, H. Muller, and W. Greiner,PRL 32, 741 (1974)
M.I. Sobel, P.J. Siemens, J.P. Bondorf, andH.A. Bethe, Nucl. Phys. A251, 502 (1975)
G.F. Chapline, M.H. Johnson, E. Teller, and M.S. Weiss, PRD 8, 4302 (1973)
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No Shock WavesNo Shock Waves
H.G. Baumgardt et al., Z. Physik A 273, 359 (1973)Peaks in tracks in AgCl crystals
Poskanzer and Greiner 1984
d/d
reviewed in H.R. Schmidt, Int. J. Mod. Phys. A6, 3865 (1991)GSI-LBL, A.M. Poskanzer et al., PRL 35, 1701 (1975)
d/dΩ
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Shock Waves AgainShock Waves Again
D.H. Rischke, H. Stoecker, and W. Greiner. PRD 42, 2283 (1990)
Flow in conical shock wavesAway side jet
J. Casalderrey-Solana, E.V. Shuryak,and D. Tracy, arXiv hep-ph/0411315 (2004)
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STARSTAR
Phys. Rev. Lett. 102, 052302 (2009)
structures are evidence of conical emission of hadrons correlated with high p⊥ particles.
C. Pruneau, QM06, S671
3-particle correlations
No clear evidence for conicalemission is observed usingcumulates.
However, see Ulery and Wang, PRC 79, 024904 (2009)
CATHIE-RIKEN Workshop:Critical Assessment of Theory and Experiment on Correlations at RHICFebruary 25-26, 2009
I think experiments not conclusive
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Should Not BeShould Not Be
Bouras, Molnar, Niemi, Xu, El, Fouchler, Greiner, Rischke, ArXiv:0902.1927
an /s ratio larger than 0.2 prevents the developmentof well-defined shock waves on timescales typical forultrarelativistic heavy-ion collisions.
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Mach ConesMach ConesMiklos’ last 10 papers have been on Mach Cones
QuickTime™ and a decompressor
are needed to see this picture.
G. Torrieri, B. Betz, J. Noronha, and M. Gyulassy, arXiv:0901.0230
Theory very complicated!
J. Noronha, M. Gyulassy, and G. Torrieri, PRL 102, 102301 (2009)
Doubts PHENIX results are dueto ordinary Mach cones
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Homework ProblemHomework Problem Assigned by Miklos at the 3rd Summer Study in 1976
Calculate p spectrum of 250 MeV/A Ne + U
Nine solutions submitted Factors of 2 - 5 away from the data
“The most successful model in reproducing the gross features of the data is the fireball model”
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SphericitySphericity
Best ellipsoid for each event by diagonalizingkinetic energy flow tensor:
pz
(Beam)
Reaction plane
x
y
z
s
py
px
P. Danielewicz and M. Gyulassy Phys. Lett. B 129, 283 (1983)M. Gyulassy, K.A. Frankel, and H. Stocker, Phys. Lett. 110B, 185 (1982)
Major axis and beam axisdetermine event plane
M. Lisa (1999)
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Polar Flow AnglePolar Flow Angle
Gyulassy:“The only true signature of collective flowis a clear maximum of dN/d cos away from = 0”
Directed Flow
M. Gyulassy, K.A. Frankel, and H. Stocker, Phys. Lett. 110B, 185 (1982)P. Danielewicz and M. Gyulassy, Phys. Lett. 129B, 283 (1983)
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Discovery of Collective FlowDiscovery of Collective Flow
Plastic Ball, Gustafsson et al., PRL 52, 1590 (1984)
Non-zero flow angle distributionfor Nb, but not CadN/dcos
Bevalac 400 MeV/A
Directed Flow
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Squeeze-outSqueeze-outbounce
squeeze squeeze
400 MeV/A Au+Au (MUL 3)
Plastic Ball, H.H. Gutbrod et al., Phys. Lett. B216, 267 (1989)Diogene, M. Demoulins et al., Phys. Lett. B241, 476 (1990)Plastic Ball, H.H. Gutbrod et al., PRC 42, 640 (1991)
Negative Elliptic Flow
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Expansion In PlaneExpansion In Plane
Hiroshi Masui (2008)
spatialanisotropy
momentumanisotropy
2
v2
Positive Elliptic Flow
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Discovery of Elliptic Flow at RHIC
Discovery of Elliptic Flow at RHIC
STAR, K.H. Ackermann et al., PRL 86, 402 (2001)
First paper from STAR
Dramatic effect:
Significant that data approach hydrofor central collisionsWas not true at lower beam energies
hydro predictions
peripheral centralpeak / valley = (1 + 2 v2) / (1 - 2 v2) = 1.8
22A. Wetzler (2005)
Elliptic Flow vs. Beam EnergyElliptic Flow vs. Beam Energy
25% most centralmid-rapidity
all v2EP
six decades
In-planeelliptic flow
squeeze-out
bounce-offspinning
powerful, widely-used tool,to study EOS ofnuclear matter
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Transverse Plane
Elliptic FlowElliptic Flow
Rescattering Converts space to
momentum anisotropy Becomes more spherical
Self-quenching Early time
thermalization
v2
t (fm/c)
Zhang, Gyulassy, Ko, Phys. Lett. B455 (1999) 45
Main contribution to elliptic flow early in the
collision
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quarks
mesons
baryons
plotted vs.trans. kinetic energy
PHENIX, PRL 98, 162301 (2007)
Scaling with Number of QuarksScaling with Number of Quarks
both axes scaled by numberof constituent quarks
nq = 2 for mesonsnq = 3 for baryons
recombination of quarksquarks have v2 before hadronization
STAR, PRL 95, 122301 (2005)
S. Voloshin, QM02, 379c (2003)
particle massdependence
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Eq.
QuickTime™ and a decompressor
are needed to see this picture.
event plane resolution
root-mean-square
mean
FluctuationsFluctuations
Data: PHOBOS+Eq.: Ollitrault, Poskanzer, and Voloshin, QM09, ArXiv
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Fluctuations and Nonflow Corr.Fluctuations and Nonflow Corr.
published corrected to Part. Plane
Ollitrault, Poskanzer, and Voloshin, QM09, arXiv
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Correction to Reaction PlaneCorrection to Reaction Plane
Ollitrault, Poskanzer, and Voloshin, QM09, arXiv
Glauber fluctuations
CGC fluctuations
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Shear ViscosityShear Viscosity
shear viscosityentropy density
Conjecture was derived from string theory but has simple interpretation based on the uncertainty principle:
Mean free path must be bigger than De Broglie wavelength. Larry McLerran
Small shear viscosity meanssmall mean free path, which meansstrongly coupled
Danielewicz and Gyulassy, PRD 31, 53 (1985)
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Viscous HydrodynamicsViscous Hydrodynamics
Romatschke2, PRL 99, 172301 (2007)
Hydro: viscosity lowers v2
Data: removing non-flow and fluctuations lowers v2
Both data and hydro need more work on these effects• But approximately at the uncertainty principle value• Thus /s is no more than 5 times bigger than the minimum value
STAR, B.I. Abelev et al., arXiv:0801.3466; PRC, submitted (2008)
= 1/(4)
estimatedremovalof non-flowand fluctuations
STAR data
non-viscous
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FutureFuture More precise multi-particle v2
Reaction Plane values For many identified species
Quark content Do charm and bottom quarks flow?
Equilibration Explain RAA and v2 at the same time
Universal understanding
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