You can find this page at http://nuclear.ucdavis.edu/~cebra/classes/phys224/phys224c.html

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PHYSICS 224C Nuclear Physics III - Experimental High Energy
You can find this page at http//nuclear.ucdavis.e
du/cebra/classes/phys224/phys224c.html
QUARTER Fall 2008LECTURES 432 Phys/Geo, TR
210 to 330 INSTRUCTOR Daniel Cebra, 539 P/G,
752-4592, cebra_at_physics.ucdavis.edu GRADERS
none TEXT No required text. The following could
be useful R.L Vogt Ultrarelativistic Heavy Ion
Collisions C.Y. Wong Introduction to High-Energy
Heavy-Ion CollisionsL.P. Csernai Introduction to
Relativistic Heavy Ion CollisionsJ. Letessier
and J. Rafelski Hadrons and Quark-Gluon
Plasma HOMEWORK There will be presentations
assigned through the quarter. EXAM  There will
be no exams for this courseGRADE DETERMINATION
Grade will be determined presentations and class
participationOFFICE HOURS Cebra (any
time) Course Overview The class will be taught
as a seminar class. We will alternate between
lectures to overview the concepts with readings
and discussions of critical papers in the field.
There will be no homework assignments, no exams.
Students are read the discussion papers ahead and
to come prepared for presentations.
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Course Outline

• Overview and Historical Perspective
• Hagedorn Bootstrap Model
• Bjorken energy density
• Basic Kinematics
• Quantum Chromodynamics
• Asymptotic freedom
• Confinement
• Chirality
• Drell-yan
•  
• Initial Conditions and First Collisions
• Glauber Model --- pre-collision and initial
  geometry (impact parameter)
• Color-Glass Condensate
• Parton Cascade ---
• Quark-Gluon Plasma Formation and Evolution
• Lattice QCD
• Hydrodynamics

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Broad Historic Developments
1896 Discovery of Radioactivity
(Becquerel) 1911 Nuclear Atom (Rutherford) 1932 Di
scovery of the neutron (Chadwick) 1935 Meson
Hypothesis (Yukawa) 1939 Liquid-Drop model of
nucear fission (Bohr and Wheeler) 1947 Discovery
of the pion (Powell) 1949 Nuclear Shell Model
(Mayer and Jensen) 1953 Strangeness Hypothesis
(Gell-Mann and Nishjima) 1953 First production of
strange particles (Brookhaven) 1955 Discovery of
the anti-proton (Chamberlain and
Segre) 1964 Quark model of hadrons (Gell-Mann and
Zweig) 1967 Electroweak model proposed (Weinberg
and Salam) 1970 Charm hypothesis
(Glashow) 1974 Discovery of the J/y (Ricther,
Ting) 1977 U Discovered and bottom inferred
(Lederman) 1980 First Quark Matter meeting
(Darmstadt, Germany) 1983 W and Z discovered
(Rubbia) 1983 Isabelle cancelled 1984 RHIC
Proposal 1986 Heavy-ion operations at the AGS and
SPS 1992 Au beams at the AGS and Pb beams at the
SPS 1995 Top quark observed (Fermilab) 2000 AuAu
operations at RHIC 2009? PbPb operations at the
LHC
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A brief history of relativistic heavy-ion
facilities
LBNL Bevalac (1980 1992) Au 0.1 to 1.15
AGeV EOS --- TPC DLS --- DiLepton
spectrometer GSI SIS () TAPS KaoS
FoPi BNL AGS (1986-1995) Si, 1994 Au 10 AGeV,
8, 6, 4, 2 E802/866/917 E810/891 E877 E878
E864 E895 E896 CERN SPS (1986-present) O
60, 200 AGeV (1986-87) S 200 AGeV (1987-1992)
Pb 158, 80, 40, 30, 20 AGeV (1994-2000),
In HELIOS(NA34) NA35/NA49/NA61(Shine) NA36
NA38/NA50/NA60 NA44 CERES(NA45)
NA52 WA85/WA94/WA97/NA57 WA80/WA9898 BNL
RHIC (2000-present) AuAu 130, 200, 62.4, 19.6,
dAu 200, CuCu 200, 62.4, 22, pp 200,
450 STAR PHENIX Phobos BRAHMS pp2pp CERN
LHC (2009?)PbPb ALICE CMS ATLAS
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Quark-Gluon Plasma
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Motivation for Relativistic Heavy Ion Collisions
Two big connections cosmology and QCD
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The phase diagram of QCD
Early universe
quark-gluon plasma
critical point ?
Tc
Temperature
colour superconductor
hadron gas
nucleon gas
nuclei
CFL
Neutron stars
r0
vacuum
baryon density
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Evolution of Forces in Nature
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Going back in time
Age Energy Matter in universe 0 1019
GeV grand unified theory of all forces 10-35
s 1014 GeV 1st phase transition (strong
q,g electroweak g, l,n) 10-10s 102 GeV 2nd
phase transition (strong q,g electro g
weak l,n) 10-5 s 0.2 GeV 3rd phase
transition (stronghadrons electrog
weak l,n) 3 min. 0.1 MeV nuclei 6105
years 0.3 eV atoms Now (1.5109 years) 310-4
eV 3 K

RHIC, LHC FAIR
RIA FAIR
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Connection to Cosmology

• Baryogenesis ?
• Dark Matter Formation ?
• Is matter generation in cosmic medium (plasma)
  different than matter generation in vacuum ?

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Sakharov (1967) three conditions for
baryogenesis

• Baryon number violation
• C- and CP-symmetry violation
• Interactions out of thermal equilibrium
• Currently, there is no experimental evidence of
  particle interactions where the conservation of
  baryon number is broken all observed particle
  reactions have equal baryon number before and
  after. Mathematically, the commutator of the
  baryon number quantum operator with the Standard
  Model hamiltonian is zero B,H BH - HB 0.
  This suggests physics beyond the Standard Model
• The second condition violation of CP-symmetry
  was discovered in 1964 (direct CP-violation, that
  is violation of CP-symmetry in a decay process,
  was discovered later, in 1999). If CPT-symmetry
  is assumed, violation of CP-symmetry demands
  violation of time inversion symmetry, or
  T-symmetry.
• The last condition states that the rate of a
  reaction which generates baryon-asymmetry must be
  less than the rate of expansion of the universe.
  In this situation the particles and their
  corresponding antiparticles do not achieve
  thermal equilibrium due to rapid expansion
  decreasing the occurrence of pair-annihilation.

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Dark Matter in RHI collisions ? Possibly (not
like dark energy)
The basic parameters mass, charge
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Basic Thermodynamics
Hot
Sudden expansion, fluid fills empty space without
loss of energy. dE 0 PdV gt 0 therefore dS
gt 0
Hot
Hot
Gradual expansion (equilibrium maintained), fluid
loses energy through PdV work. dE -PdV
therefore dS 0
Hot
Isentropic Adiabatic
Cool
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Nuclear Equation of State
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Nuclear Equation of State
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Golden Rule 1 Entropy per co-moving volume is
conserved
Golden Rule 3 All chemical potentials are
negligible
Golden Rule 4
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gS
Start with light particles, no strong nuclear
force
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gS
Previous Plot
Now add hadrons feel strong nuclear force
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gS
Previous Plots
Keep adding more hadrons.
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How many hadrons?
Density of hadron mass states dN/dM increases
exponentially with mass.
Broniowski, et.al. 2004
TH 2?1012 oK
Prior to the 1970s this was explained in several
ways theoretically Statistical Bootstrap
Hadrons made of hadrons made of hadrons Regge
Trajectories Stretchy rotators, first string
theory
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Hagedorn Limiting Temperature
Ordinary statistical mechanics
For thermal hadron gas (somewhat crudely)
Energy diverges as T --gt TH Maximum achievable
temperature? a veil, obscuring our view of the
very beginning. Steven Weinberg, The First
Three Minutes (1977)
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(No Transcript)
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What do I mean Bjorken?
Boost-invariant
Increasing E
y
y
dN/dy
Inside-out 1 dimensional
0
yy-ybeam
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Impact of Bjorken
X

• dN/dy distribution is flat over a large region
  except near the target.
• v2 is independent of y over a large region except
  near the target. (2d-hydro.)
• pT(y) described by 1d or 2d-hydro.
• Usual HBT interpretation starts from a
  boost-invariant source.
• T(t) described by 1d-hydro.
• Simple energy density formula

X
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Notations
Well be using the following notations proper
time and rapidity
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Most General Boost Invariant Energy-Momentum
Tensor
The most general boost-invariant energy-momentum
tensor for a high energy collision of two very
large nuclei is (at x3 0)
which, due to
gives
There are 3 extreme limits.
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Limit I Free Streaming
Free streaming is characterized by the following
2d energy-momentum tensor
such that
and

• The total energy E e t is conserved, as
  expected for
• non-interacting particles.

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Limit II Bjorken Hydrodynamics
In the case of ideal hydrodynamics, the
energy-momentum tensor is symmetric in all three
spatial directions (isotropization)
such that
Using the ideal gas equation of state,
, yields
Bjorken, 83

• The total energy E e t is not conserved, while
  the total entropy S is conserved.

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Most General Boost Invariant Energy-Momentum
Tensor
Deviations from the
scaling of energy density, like
are due to longitudinal
pressure , which does work
in the longitudinal direction modifying the
energy density scaling with tau.

• Non-zero positive longitudinal
• pressure and isotropization

? deviations from
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Limit III Color Glass at Early Times
In CGC at very early times
(Lappi, 06)
we get, at the leading log level,
such that, since
Energy-momentum tensor is
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D. Gross
QCD to the rescue!
H.D. Politzer
F. Wilczek
Replace Hadrons (messy and numerous) by Quarks
and Gluons (simple and few)
American
QCD Asymptotic Freedom (1973)
e/T4 ? gS
Thermal QCD QGP (Lattice)
In 1972 the early universe seemed hopelessly
opaqueconditions of ultrahigh temperaturesproduc
e a theoretically intractable mess. But
asymptotic freedom renders ultrahigh temperatures
friendly Frank Wilczek, Nobel Lecture (RMP 05)
Hadron gas
Karsch, Redlich, Tawfik, Eur.Phys.J.C29549-556,20
03
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Nobel prize for Physics 2005
Before QCD we could not go back further than
200,000 years after the Big Bang. Todaysince
QCD simplifies at high energy, we can extrapolate
to very early times when nucleons meltedto form
a quark-gluon plasma. David Gross, Nobel
Lecture (RMP 05)
gS
Thermal QCD -- i.e. quarks and gluons -- makes
the very early universe tractable but where is
the experimental proof?
n Decoupling
Nucleosynthesis
ee- Annihilation
Heavy quarks and bosons freeze out
QCD Transition
Mesons freeze out
Kolb Turner, The Early Universe
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The main features of Quantum Chromodynamics

• Confinement
• At large distances the effective coupling between
  quarks is large, resulting in confinement.
• Free quarks are not observed in nature.
• Asymptotic freedom
• At short distances the effective coupling between
  quarks decreases logarithmically.
• Under such conditions quarks and gluons appear to
  be quasi-free.
• (Hidden) chiral symmetry
• Connected with the quark masses
• When confined quarks have a large dynamical mass
  - constituent mass
• In the small coupling limit (some) quarks have
  small mass - current mass

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Quarks and Gluons
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Basic Building Blocks ala Halzen and Martin
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Quark properties ala Wong
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What do we know about quark masses ?
Why are quark current masses so different ? Can
there be stable (dark) matter based on heavy
quarks ?
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Elementary Particle Generations
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Some particle properties
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Elemenary particles summary
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Comparing QCD with QED (Halzen Martin)
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Quark and Gluon Field Theory QCD (I)
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Quark and Gluon Field Theory QCD (II)
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Quark and Gluon Field Theory QCD (III)

• Boson mediating the q-qbar interaction is the
  gluon.
• Why 8 and not 9 combinations ? (analogy to flavor
  octet of mesons)
• R-Bbar, R-Gbar, B-Gbar, B-Rbar, G-Rbar, G-BBar
• 1/sqrt(2) (R-Rbar - B-Bbar)
• 1/sqrt(6) (R-Rbar B-Bbar 2G-Gbar)
• Not 1/sqrt(3) (R-Rbar G-Gbar B-Bbar) (not
  net color)

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Hadrons
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QCD a non-Abelian Gauge Theory
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Particle Classifications
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Quarks
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Theoretical and computational (lattice) QCD
In vacuum - asymptotically free quarks have
current mass - confined quarks have constituent
mass - baryonic mass is sum of valence quark
constituent masses Masses can be computed as a
function of the evolving coupling Strength or
the level of asymptotic freedom, i.e. dynamic
masses.
But the universe was not a vacuum at the time of
hadronization, it was likely a plasma of quarks
and gluons. Is the mass generation mechanism the
same ?
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Confinement Represented by Bag Model
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Bag Model of Hadrons
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Comments on Bag Model
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Still open questions in the Standard Model
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Why RHIC Physics ?
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Why RHIC Physics ?