Oscillations of the quark-gluon plasma

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Oscillations of the quark-gluon plasma
or

• from oscillations to fast thermalization

Wojciech Florkowski
dedicated to Professor Andrzej Bialas on the
occasion of His 70-th birthday
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1. Development of the color-flux-tube model by
Bialas and Czyz
color-flux-tube model Casher, Neuberger,
Nussinov, PR D20 (1979) 179
development by Bialas and Czyz in the series of
papers published in the 1980s
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• - A. Bialas and W. Czyz, Boost-invariant
  Boltzmann-Vlasov equations for relativistic
  quark-antiquark plasma, Phys. Rev. D30 (1984)
  2371
• - A. Bialas and W. Czyz, Chromoelectric flux
  tubes and the transverse momentum distribution in
  high-energy nucleus-nucleus collisions, Phys.
  Rev. D31 (1985) 198
• - A. Bialas and W. Czyz, Oscillations of
  relativistic, boost-invariant quark-antiquark
  plama, Z. Phys. C28 (1985) 255
• - A. Bialas and W. Czyz, Conversion of color
  field into q anti-q matter in the central region
  of high-energy heavy-ion collisions, Nucl. Phys.
  B267 (1986) 242
• A. Bialas and W. Czyz, Production and collective
  motion of q anti-q plasma in heavy-ion
  collisions, Acta Phys. Pol. B17 (1986) 635
• and more others ...

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• chromoelectric fields stronger than in
  elementary e e- annihilations
• Biro, Nielsen, Knoll, Nucl. Phys. B245 (1984)
  449
• (increased multiplicity, increased production of
  strange particles)
• oscillations of the quark-antiquark plasma
• fast (t0lt1 fm/c) production of dense matter

k number of color charges q which span the
initial field, g coupling constant
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A. Bialas, W. Czyz, A. Dyrek, and WF,
Oscillations of quark-gluon plasma generated in
strong color fields, Nucl. Phys. B296 (1988) 611
time dependence of the chromoelectric field (LHS)
and the energy density of quarks and gluons (RHS)
for various values of the parameter k
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time dependence of the average transverse (LHS)
and longitudinal (RHS) momentum of quarks and
gluons for various values of the parameter k
8 gluon fields are separated into 2 neutral
fields (chromoelectric field E3 , E8) and 6
charged gluons (treated as particles together
with quarks)
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A. Dyrek and WF, Production of heavy quarks in
strong chromoelectric fields, Nuovo Cim. A102
(1989) 1013
the ratio of strange quarks to up and down quarks
quantitatively similar results to those obtained
by P. Koch, B. Muller, and J. Rafelski, Phys.
Rep. 142 (1986) 167
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2. Early-thermalization in relativistic
heavy-ioncollisions

• the data collected at RHIC suggest that matter is
  well thermalized and exhibits collective behavior
  (bound states above TC, Shuryak plasma
  instabilities, Mrówczynski Hawking-Unruh effect,
  Kharzeev)
• 2) already in more elementary collisions we
  observe thermal features, Boltzmann distributions
  in transverse momentum, Hagedorn, 1960s

• A. Bialas, Fluctuations of string tension and
  transverse-mass distribution Phys. Lett. B31
  (1999) 301

gaussian fluctuations of the string tension can
account for the thermal distribution of
transverse mass of particles created in decay of
a color string
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the measured transverse-momentum spectra have
thermal (exponential) shape, Hagedorn, 1960s
string models of hadronic collisions use the
Schwinger formula
Bialas appropriate averaging over ? may produce
an exponential function
fluctuations may appear due to stochastic nature
of the QCD vacuum (H.G. Dosch, Yu. A. Simonov)
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my personal follow-up of this idea, WF, Schwinger
tunneling and thermal character of hadron
spectra, Acta Phys. Pol. B35 (2004) 799
quark spectra in the color-flux tube model are
exponential due to the dynamic oscillations of
the chromoelectric field E
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oscillations in varying chromoelectric fields may
explain the origin of the thermal spectra in
heavy-ions but this effect is not capable of
describing thermal features observed in
elementary processes it is conceivable, however,
that the effect of the stochastic vacuum plays an
additional role in heavy-ion collisions leading
to even more pronounced thermalization effects
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Instead of Conclusions ...
Drogi Panie Profesorze! z okazji tego Jubileuszu
prosze przyjac najserdeczniejsze zyczenia wielu
lat zdrowia i pomyslnosci, a takze podziekowania
za wszystkie naukowe inspiracje