Collective property of QGP in highenergy

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Collective property of QGP in high-energy
heavy-ion collisions at LHC Inst. of Physics,
Univ. of Tsukuba ShinIchi Esumi
Contents(1) charged
multiplicity, stopping(2) chemical and thermal
property(3) elliptic flow and quark
coalescence(4) space-momentum-correlation in
HBT(5) jet modification in away-side (6) jet
modification in same-side ridge(7) mach-cone
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Total charged particle multiplicity distribution
Measured trend at AGS-SPS-RHIC energies is
extrapolated to LHC energy. About 60 increase
in dN/dh from RHIC to LHC, which is 2.6 times in
total yield.
W. Busza, LHC Workshop, May/2007
W. Busza, LHC Workshop, May/2007
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net-Baryon distribution (stopping -gt transparent)
This tells us how the initial Baryon density is
distributed in the final rapidity density. A wide
net-Baryon free region will be formed in the
mid-rapidity.
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Chemical equilibrium
Tch 160170MeV
Chemical freeze-out the end of inelastic
scattering during collisions, where particle
abundances are frozen. Various particles ratios
and yields are fitted with thermal models in
order to extract a common chemical freeze-out
temperature and potentials for all the particle
species at each beam energy.
Phys. Rev. C 73(2006) 034905
P.Braun-Munzinger, LHC Workshop, May/2007
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Elliptic flow v2 vs h
Memory of the initial geometrical overlap and
pressure followed by the collective expansion.
Im still puzzled by the shape peak structure in
the mid-rapidity unlike the most of all the other
experimental observables.
W. Busza, LHC Workshop, May/2007
19.6 - 200 GeV
v2 7.5
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Although the mass ordering is rather well
reproduced by hydro-dynamic picture, later
hadronic re-scattering during the collision seems
to be important to reproduce h dependence of v2
as well as for pT dependence of v2 and pT
distributions.
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Phys. Rev. Lett. 99, 052301 (2007)
Particle identified v2 at RHIC
Number of constituent quark scaling in hadron v2
as well as multi-strange baryon v2 v2 is already
established during the quark phase before the
hadronization. This seems to be true even for
heavy quark like charm.
Phys. Rev. Lett. 98, 172301 (2007)
QM06
STAR preliminary
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Kinetic-thermal equilibrium
Stronger radial expansion is expected with
similar thermal freeze-out temperature or
slightly lower temperature...
Kinetic-thermal freeze-out the end of elastic
scattering during collisions, where momentum
spectra are frozen. pT spectra are fitted with
hydro-dynamics inspired blast-wave model in
order to extract a common thermal freeze-out
temperature and radial expansion velocity for all
the particle species at each beam energy.
Tfo 100140MeV
K.Schweda, ISMD, Aug/2007
bT
S.Bass, LHC Workshop, May/2007
Tfo
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Radial flow
Stronger radial expansion will enhance the effect
of mass dependence of both transverse momentum
spectra and v2. We will know about the
freeze-out temperature and final transverse flow
velocity, but in general we would not know where
the origin of the expansion is partonic or
hadronic. Detailed shape analysis of v2 and pT
spectra could tell us about it in model dependent
ways.
C. Ko, LHC Workshop, May/2007
C. Ko, LHC Workshop, May/2007
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Source size measurement with HBT radius
Very weak energy dependence on the measured
radius parameters from AGS-SPS-RHIC. HBT radii do
not represent the entire source but the local
source size given by space-momentum correlation,
because of a dynamically expanding source in
stead of a static source.
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positive x-p correlation shift in Xout positive
x-t correlation reduces Rout
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Jet pair correlation
Suppression at higher pT Modification at low-mid
pT
S.Kniege, ISMD 2007
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3 particle correlation
mach-cone/Cherenkov-like or deflected jets
J. Ulery, ISMD 2007
f2-ftrigger (rad)
90(deg)
80(deg) from away side center
f1-ftrigger (rad)
QM06
deflected
mach-cone
data
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Modification of away-side jet shape
Softening of away side head region, which is
consistent with energy loss scenario.
Away side shoulder region is universal, which is
independent with trigger pT and centrality
selection.
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Modification of same-side jet shape ridge
J. Bielcikova, ISMD 2007
jet slope ridge slope inclusive slope
Same side ridge is also as soft as inclusive.
STAR preliminary
pTtrig (GeV/c)
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CERN-LHC-ATLAS
CERN-LHC-ALICE
Bulk property at LHC(1) charged
multiplicity, stopping(2) chemical and thermal
property(3) elliptic flow and quark
coalescence(4) space-momentum-correlation in
HBT(5) jet modification in away-side (6) jet
modification in same-side ridge(7) mach-cone
CERN-LHC-CMS
GSI-FAIR-CBM
BNL-RHIC-PHENIX
BNL-RHIC-STAR