Heavy ion collisions and Lattice QCD at finite baryon density Krzysztof Redlich

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Heavy ion collisions and Lattice QCD
at finite baryon density

Krzysztof Redlich
QCD Thermodynamics
!
?
?

• Heavy Ion
• Phenomenology

Lattice Gauge Theory
Equation of state at finite baryon density
Freezeout and critical conditions
Based on common work with
Frithjof Karsch Abdel-Nasser
Tawfik
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Chemical freeze out curve from heavy ion data
coincides with freezeout T at RHIC and SPC
AGS, SPS, RHIC F. Becattini, et al. P.
Braun-Munzinger, et al. J. Cleymans, et al. M.
Kaneta Nu Xu J. Stachel, et al. SIS R.
Averbeck, R. Holzmann, V. Metag, R. S. Simon H.
Oeschler, et al..

Thermal Freezeout see recent results of CERES
Collaboration Broniowski, Florkowski
J. Cleymans K.R.
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QCD at non-vanishing chemical potential
Bielefeld-Swansea
approach
C.R. Allton, et al..
complex fermion determinant
Taylor expansion of
,
From dependence of chiral
susceptibilities
4
Taylor expansion of resonance pressure
Factorization of the baryonic pressure
baryon mass spectrum
Compare wich LGT results
Consequences

For fixed any ratio of
these observables is T-independent
the ratio of the O(2) and O(4) coefficients
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QCD partition fuction from LGT and Phenomenology
F. Karsch, A. Tawfik, K.R.
factorization
Taylor cooficients of cosh(x)
check T-dependence in F(T)
required
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QCD partition fuction from LGT and Phenomenology
factorization
Taylor cooficients of cosh(x)
S. Ejiri, et al..
S. Ejiri, et al..
check T-dependence in F(T)
required
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Hadron Mass Spectrum versus quark mass
chiral limit



quenched limit



from LGT or Bag Model



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Hadron Mass Spectrum LGT and Bag model results
F. Karsch, A. Tawfik, K.R.
LGT results for pion mass dependence of and
their parity partners
2
QCDSF Coll., M. Göckeler, et al..
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Hadron resonance gas model and LGT


thermodynamics
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Deconfinement is density driven - (percolation)
Hadron resonance gas partition function
provides good descritpion of QCD
thermodynamics
LGT result shows strong dependence of on
and , however for
and for all
A. Peikert, et al..

hadrons
hadrons
glubals
lines of constant energy density in HG
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Phase boundary of fixed energy density versus
chemical freezeout
Spliting of chemical freezeout and phase
boundary surface most likely appears when the
densities of mesons and baryons are
comparable For Elt40 AGeV strong collective
effects in hadronic medium are to be expected


LGT

SPS 40 AGeV

see also NJL results on critical conditions (T.
Kunihiro et al.)
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Chiral critical point in 3-flavour QCD
F.
Karsch et al.
Strong dependence of the position of the
second order endpoint on the quark mass!


0.3
T MeV
Pure Gauge
0.25
1-st order
crossover transition
0.2
2-en ord.
0.15
0.1
N_f3, m0.1 N_f3, m0.005
Strong dependence of the slope on the quark mass
0.05
miu GeV
0
0.2
0.4
0.6
0.8
1.0
1.2
0
p4 improved action
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Conclusions
Hadron Resonance Gas Partition Function
provides the consistent description of

• particle yields obtained
  the equation of state in
• in heavy ion collisions from
  confined phase obtained
• SIS-gtAGS-gtSPS-gtRHIC in
  LGT at
• Thus the system created
  in the late stage of heavy
• ion collisions
  is of thermal origin
  
  

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Bag Model and Hadron Masses

• --------------------
• --------------------
• ---------------------
• ------- ---
  
• ----------------------
  
• ----------B-----------
  surface boundary
• 
  conditions
  
• Hadron Masses from
  
• for and

q
g
q
q
g