Multi module models for heavy ion reactions poster T34

1
Multi module models for heavy ion
reactions(poster T34)

• L.P. Csernai, A. Anderlik, Cs. Anderlik, Ø.
  Heggø-Hansen, J. Manninen, E. Molnár, A. Nyiri,
  D. Röhrich, and K. Tamosiunas
• U of Valencia V.K. Magas
• U of Oulu A. Keranen,
• Los Alamos National Lab. D.D. Strottman, B.
  Schlei
• U of Sao Paulo F. Grassi, Y. Hama
• U of Rio de Janeiro T. Kodama
• U of Frankfurt H. Stöcker, W. Greiner
• Bergen Computational Physics Lab. EU Research
  Infrastructure,BCCS, Unifob AS, University of
  Bergen, Norway

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Multi Module Modeling

• Initial state - Pre-equilibrium Parton Cascade
  M. Coherent Yang-Mills Magas
• Local Equilibrium ? Hydro, EoS
• Finding the F.O. hypersurface Schlei,
  Tamosiunas
• Final Freeze-out Kinetic models, measurables.
• If QGP ? Sudden and simultaneous hadronization
  and freeze out Manninen, Keranen
• Measurables dN/dy, v, v, HBT, Strangeness,
  Entropy puzzle, Nyiri, Molnar,

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Multi Module Modeling
FO surface
FO transfer
Some modules (tasks) can be divided further into
smallee, well separable units. Saves work and
distributes the computational effort!
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Multi Module Modeling on GRID
Qn a network of computers coupled into a
computational GRID repeated tasks can be
performed in much shorter time.
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Fire streak picture - Only in 3 dimensions!
Myers, Gosset, Kapusta, Westfall
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Initial stage Coherent Yang-Mills model
--- See poster T6 !!! ---
Magas, Csernai, Strottman, Phys. Rev. C64 (01)
014901
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Yo Yo Dynamics
wo/ dissipation
Hydro init. State at full stopping of streaks.
Uniform
Dissipative processes may lead to even earlier
local equilibration gt Hydro may set in earlier
!!!
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Modified Initial State
3rd flow component
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Matching Conditions Between Modules

• Conservation laws
• Nondecreasing entropy

Each reaction modeling module has to be matched
to the previous and subsequent module on a
space-time hypersurface. The conditions can be
solved easily. Yields, via the Taub adiabat
and Rayleigh line, the final state behind the
hyper-surface. Very important a freeze out. gt
cut and distorted non-eq. Final distributions !!!
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3-dim Hydro for RHIC Energies
AuAu ECM65 GeV/nucl. b0.5 bmax As0.08
gt s10 GeV/fm
e GeV / fm3 T MeV
.
.
t18.2 fm/c, Tmax 417 MeV, emax 19.4 GeV/fm3,
Lx,y 1.45 fm, Lz0.145 fm
EoS p e/3 - 4B/3
4 times elongated !!
B 397 MeV/fm3
34.8 x 8.7 fm
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Freeze-Out Hyper-Surface Extraction with Digital
Image Processing Techniques VESTA and Projections
of FOHS (e.g., Firestreaks for Au Au _at_ RHIC)
Bernd R. Schlei (T-1) - LA-UR-03-3410 ---
See poster T8 !!! ---
In 31 D Hydrodynamical Calculations, VESTA is
useful for the Graphical Rendering of Projections
of FOHS. A Construction of a 4D FOHS requires a
Generalization of VESTA into 4D.
xyz - Projection
t fixed
xtz - Projection
y fixed
y
z
x
Impact Parameter b 0.5
t
31 D Hydrodynamic Density Data are based on
Firestreak Initial Conditions V. K. Magas, L.
P. Csernai, D. Strottman, Nucl. Phys. A712 (2002)
167.
z
x
Impact Parameter b 0.5
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Directed tr. flow
3rd flow component
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Phase-Space FO probability
Freeze-out hypersurface in space-time
Time-like F.O. no cut, but distorted post FO
distribution may result !!
Space-like FO. cut, and distorted, non-thermal
distributions arise!
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Phase-Space FO probability
A. Anderlik, E. Molnar, et al.
A
B
d3?? u?
C
Time-like F.O.
Uniform 1
D
E
F
Space-like F.O.
Cut is at P 0.
P a.u.
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Freeze out distribution with rescattering from
kinetic model across a layer
V0
V. Magas, et al., Heavy Ion Phys.9193-216,1999
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3rd flow component and QGP

• Csernai Röhrich Phys.Lett.B458(99)454
  observed a 3rd flow component at SPS energies,
  not discussed before.
• Also observed that in ALL earlier fluid dynamical
  calculations with QGP in the EoS there is 3rd
  flow comp.

• The effect was absent without QGP.
• In string and RQMD models only peripheral
  collision showed the effect (shadowing).

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3rd flow component
Hydro Csernai, HIPAGS93
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V-1 flow at RHIC/STAR
protons
pions
The slope in the middle is statistically not
significant within the present errors
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3rd flow-comp. in PbPb, Elab40 and 158GeV
NA49
A. Wetzler
v1 ? 0
158 GeV/A
Different scale for 40 and 158 GeV!
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Conclusions

• v1 ? 0 , is measured! New possibility to
  study collective matter behavior
• 3-dim models and 3-dim initial conditions are
  needed to fit data
• Impact parameter / multiplicity dependence is
  essential (more data)
• Detailed models including equilibrium and
  non-equilibrium features will be required to
  describe the data