How to understand the creation of matter

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How to understand the creation of matter
Link to cosmology A QCD/QGP/RHIC primer The
discovery of the sQGP Towards the most
fundamental questions

• Rene Bellwied
• Wayne State University
• (bellwied_at_physics.wayne.edu)
• Student Colloquium
• WSU, September 29th, 2008

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Matter in the universeA problem of galactic
proportions

• In spiral galaxies, the rotation curve remains at
  about the same value at great distances from the
  center
• This means that the enclosed mass continues to
  increase even though the amount of visible,
  luminous matter falls off at large distances from
  the center.

• Something else must be adding to the gravity of
  the galaxies without shining. Dark Matter !
• Accounts for gt 90 of the mass in the universe.

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Dark Matter vs. Luminous Matter
distributionBullet Cluster, 3.4 Billion
Lightyears from Earth X-ray image vs.
gravitational lensing
Cluster contents by mass 2 galaxies 13
hot gas 85 dark matter Dynamics of a galaxy
cluster are governed by its dark matter
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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)
• 10-10 s 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 310-4 eV 3 K
• (13.7 billion years)

RHIC, LHC FAIR
FRIB FAIR
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The first second of the universe
AP NP HEP

• from D.J. Schwarz, astro-ph/0303574

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Analogies and differences between QED and QCD
to study structure of an atom
electron
F 1/r2
separate constituents Imagine our understanding
of atoms or QED if we could not isolate charged
objects!!
nucleus
neutral atom
Confinement fundamental crucial (but not
understood!) feature of strong force - colored
objects (quarks) have ? energy in normal vacuum
F r
quark
Strong color field Force grows with separation !!!
white ?0 (confined quarks)
white proton (confined quarks)
white proton
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The main features of Quantum Chromodynamics (QCD)
(Nobel Prize 2004)

• 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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The evolution of luminous matter
Standard model is symmetric. All degrees of
freedom are massless.
Electro-weak symmetry breaking via Higgs field
(Dm of W, Z, g) Mechanism to generate current
quark masses (but does not explain their
magnitude)
QCD phase transition (I) chiral symmetry
breaking via dynamical quarks. Mechanism to
generate constituent quark masses (but does not
explain hadronization)
QCD phase transition (II) Confinement to
hadrons. Mechanism to generate hadron properties
(but does not explain hadron masses 51010
935 MeV/c2)
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The basic questions

• a.) Measure a phase transition, characterize the
  new phase (degrees of freedom). Is there
  deconfinement and chiral symmetry restoration ?
• b.) Measure the de-excitation. Was dark matter
  formed at the same time than luminous matter ?
  Can we generate black holes in the laboratory ?
• c.) Measure the evolution of luminous matter
  formation. Learn about hadronization. Why is the
  free quark mass only a small part of the nucleon
  mass ? How do particles acquire mass ?

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Generating a deconfined state

• Present understanding of Quantum Chromodynamics
  (QCD)
• heating
• compression
• ? deconfined color matter !

Nuclear Matter (confined)
Hadronic Matter (confined)
Quark Gluon Plasma deconfined !
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Expectations from Lattice QCD
?/T4 degrees of freedom
confined few d.o.f.
deconfined many d.o.f.
TC 173 MeV 2?1012 K 130,000?TSuns
core ?C ? 0.7 GeV/fm3
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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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Relativistic Heavy Ion Collider (RHIC)
1 mile
v 0.99995?c
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Study all phases of a heavy ion collision
If the QGP was formed, it will only live for
10-21 s !!!! BUT does matter come out of this
phase the same way it went in ???
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Study all phases of a heavy ion collision
If the QGP was formed, it will only live for
10-21 s !!!! BUT does matter come out of this
phase the same way it went in ???
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microexplosions femtoexplosions
?s 0.1 ?J 1 ?J
? 1017 J/m3 5 GeV/fm3 1036 J/m3
T 106 K 200 MeV 1012 K
rate 1018 K/s 1035 K/s
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Proving the existence of a new phase of
matterCan we prove that we have a phase
thatbehaves different than elementary pp
collisions ?

• Three steps
• a.) prove that the phase is partonic
• b.) prove that the phase is collective
• c.) prove that the phase characteristics (state
  variables) are different from the QCD vacuum

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Proof (a) for partonic medium creationShooting a
high momentum particle through a dense medium
idea pp collisions _at_ same ?sNN 200 GeV as
reference
p
p
? what happens in AuAu to jets which pass
through medium?

• Prediction scattered quarks radiate energy (
  GeV/fm) in the colored medium
• quenches high pT particles
• kills jet partner on other side

?
AuAu
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RAA and high-pT suppression
STAR, nucl-ex/0305015
pQCD Shadowing Cronin
energy loss
pQCD Shadowing Cronin Energy Loss

• Deduced initial gluon density at t0 0.2 fm/c
  dNglue/dy 800-1200
• 15 GeV/fm3, eloss 15cold nuclear matter
  (compared to HERMES eA)
  (e.g. X.N. Wang nucl-th/0307036)
• SYSTEM NEEDS TO BE PARTONIC

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Proof (b) is the matter behaving collective ?
elliptic (anisotropic) flow
Flow
Mid-central collision
Y
Out-of-plane
In-plane
Reaction plane
Flow
X
Dashed lines hard sphere radii of nuclei
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Proof (c) new phase leads to new matter
production mechanism The medium consists of
constituent quarks ?Massive quasiparticles
instead of current quarks ?
baryons
mesons
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Elliptic flow exists and its magnitude is
described by ideal hydrodynamics !
Strong collective flow elliptic expansion
with mass ordering
Hydrodynamics strong coupling, small mean free
path many interactions NOT plasma-like system
behaves liquid-like
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A surprise ideal liquid behavior
First time in heavy-ion collisions we created a
system which is in quantitative agreement with
ideal hydrodynamic model. The new phase behaves
like an ideal liquid rather than a plasma. Not
anticipated. In stark contrast to pQCD.
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How strong is the coupling ?
Simple pQCD processes do not generate sufficient
interaction strength. Navier-Stokes type
calculation of viscosity yield a near perfect
liquid Viscous force 0. We have made a sQGP
not the anticipated wQGP.
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Experimental verification at RHIC
RB, J.Phys.G35044504 (2008)
Lacey et al., PRL 98 (2007) 092301
The quantum limit has been reached at RHIC and
has been independently verified in several
measurements of collective effects
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Lessons from RHIC The Quark SoupAIP
ScienceStory of 2006
Hirano, Gyulassy (2006)
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A huge cross-disciplinary effort to understand
the new phase of matterinvolving string theory,
plasma physics, astrophysics, and high energy
physics
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An example lower viscosity bound predicted in
super-symmetric strong quantum field theory
Motivated by calculation of lower viscosity bound
in black hole via supersymmetric N4 Yang Mills
theory in AdS (Anti deSitter) space
400 times less viscous than water,10 times less
viscous than superfluid helium !
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Explaining the Connection

• Maldacenas extraordinary conjecture

1) Weakly Coupled (classical) gravity in
Anti-deSitter Space (AdS)
2)
3) Strongly Coupled (Conformal) gauge Field
Theories (CFT)
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Suggested Reading

• November, 2005 issue of Scientific American
• The Illusion of Gravity
• J. Maldacena
• A test of this prediction comes from the
  Relativistic Heavy Ion Collider (RHIC) at
  BrookhavenNational Laboratory, which has been
  colliding gold nuclei at very high energies. A
  preliminary analysis of these experiments
  indicates the collisions are creating a fluid
  with very low viscosity. Even though Son and his
  co-workers studied a simplified version of
  chromodynamics, they seem to have come up with a
  property that is shared by the real world. Does
  this mean that RHIC is creating small
  five-dimensional black holes? It is really too
  early to tell, both experimentally and
  theoretically. (Even if so, there is nothing to
  fear from these tiny black holes-they evaporate
  almost as fast as they are formed, and they
  "live" in five dimensions, not in our own
  four-dimensional world.)

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Where do we go from here ?

• We found strong coupling where we expected weak
  coupling (the sQGP, the ideal liquid)
• We found evidence for massive sub-structures
  above the critical temperature (constituent
  quarks or quasi-particles)
• We found collective behavior above the critical
  temperature.
• - The degrees of freedom above Tc will form all
• baryonic matter in the universe.
  Cosmologically the system was sufficiently big to
  talk about a phase.
• - How is baryonic mass generated ?
• - Is the liquid state a quantum black hole ?

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The future is bright
A three prong approach lower energy better
facility higher energy
RHIC-II RHIC upgrade with higher luminosity
and upgraded detectors
LHC Large Hadron Collider with ALICE, CMS,
ATLAS
FAIR Facility for Antiproton Ion Reseach
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Exciting timesgoing up and down in energy
LHC Heavy Ions gt 2009 critRHIC
2009-2011, FAIR gt 2012
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Measuring pp/AA in all LHC experiments

• ALICE
• Dedicated most versatile heavy ion detector
• Important for particle identified fragmentation
  measurements in pp
• CMS/ATLAS
• Dedicated most versatile pp detectors
• Important for calorimeter based jet measurements
  in AA.

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Heavy Ion Physics at the LHC Check the blog
(http//uslhc.us)

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New / future analysesAnalogy to the early
universe - evolution of critical fluctuations
Heavy-ion Collisions Rapid Expansion
collision evolution
particle detectors
The Universe Slow Expansion
expansion and cooling
kinetic freeze-out
distributions and correlations of produced
particles
hadronization
lumpy initial energy density
QGP phase quark and gluon degrees of freedom
collision overlap zone
quantum fluctuations
credit NASA
? 0 fm/c
? 10 fm/c
?01 fm/c
particle distribution in h and f in STAR
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Our effort _at_ WSU

• My group at WSU
• Sarah LaPointe
• Vera Loggins
• Chanaka De Silva
• Anthony Timmins
• My colleagues at WSU
• Claude Pruneau
• Sergei Voloshin
• Tom Cormier
• Sean Gavin
• Monika Sharma
• Muhamed Elnimir
• Jocelyn Mlynarz
• Larry Tarini
• George Moschelli
• Raj Pokharel