1. The 'Little Bang’ in the Laboratory - Physics at the LHC
Christina Markert
Big Bang
Quarks and Strong Interaction
Heavy Ion Collisions ‘Little Bang’
Our Heavy Ion Group at UT Austin
Conclusions
Christina Markert Physics Workshop UT Austin April

2. 1.Can we produce anti matter here on earth ?
Questions
1.Can we produce anti matter here on earth ?
2.Can we create matter out of energy ?
3.Is the proton the smallest building block
of nuclear matter ?
4.Can we accelerate particles up to nearly the
speed of light ?
5.Can we observe a single quark ?
Christina Markert Physics Workshop UT Austin April

3. Our basic Questions are:
What is matter made of ?
How does matter organize itself
& stay together?
How does matter behave?
Christina Markert Physics Workshop UT Austin April

4. Space Time Diagram of the Early Universe
crystal
molecule
atom
nuclei
proton
Expansion:
Temperature decrease
Density decreases
Volume expands
It takes time
More structure
quarks
Universe is
13*109
Years old
The Cosmic Timeline
Christina Markert Physics Workshop UT Austin April

5. What do we know about the smallest building blocks?
Christina Markert Physics Workshop UT Austin April

6. Quarks in a Neutron or Proton = Mass
Theory of
strong force:
Quantum
Chromo
Dynamics
Quarks are the smallest building blocks of massive matter
Based on quark interactions ( ≠ 935 MeV/c2) ?
Christina Markert Physics Workshop UT Austin April

7. Analogies and differences between QED and QCD
to study structure of an atom…
electron
…separate constituents
nucleus
QED Quantum Electro Dynamics
neutral atom
Confinement: fundamental & crucial (but not understood!) feature of strong force
- colored objects (quarks) have  energy in normal vacuum
quark-antiquark pair
created from vacuum
quarks
u,d, (s,c,t,b)
quark
Strong color field
Force grows with separation !!!
“white” 0 (meson)
(confined quarks)
“white” proton (baryon)
(confined quarks)
“white” proton
QCD Quantum Chromo Dymanics
Christina Markert Physics Workshop UT Austin April

8. Generating a deconfined state
Present understanding of Quantum Chromodynamics (QCD)
heating
compression
 deconfined matter !
Quark Gluon Plasma
deconfined !
Hadronic Matter
(confined)
Nuclear Matter
(confined)
Christina Markert Physics Workshop UT Austin April

9. Going back in time…
Christina Markert Physics Workshop UT Austin April

10. Quark Gluon Plasma is another phase of matter!
Phase Transitions
ICE
WATER
Add heat
Quark Gluon Plasma is another phase of matter!
Christina Markert Physics Workshop UT Austin April

11. Phase Diagram We heat up the system Pressure
Christina Markert Physics Workshop UT Austin April

12. Create Quark Gluon Plasma
Hadrons
Quark Gluon Plasma q q
Compress and Add heat
T = 1,000,000,000,000 K
Christina Markert Physics Workshop UT Austin April

13. Phase Diagram of Nuclear Matter
Temperature
hadrons quarks and gluons hadrons
LHC
QGP
RHIC Tc
Center of mass energies:
for different accelerators
AGS: √s ~ GeV
SPS : √s ~ GeV
RHIC: √s ~ 200 GeV
LHC: √s ~ 5500 GeV
SPS
AGS
Baryochemical potential 
Christina Markert Physics Workshop UT Austin April

14. Phase transition of nuclear matter predicted
Gross, Politzer, Wilczek win 2004 Nobel Prize in physics for the theory of asymptotic freedom in strong interaction.
The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) was built to
measure the phase transition of nuclear matter to an ‘asymptotically free’ partonic state (deconfined) under the condition of maximum particle and energy density. (after Big Bang ?)
Wilczek
Christina Markert Physics Workshop UT Austin April

15. What can we do in the laboratory ?
a.) Re-create the conditions as close as possible to the Big Bang, i.e. a condition of maximum density and minimum volume in an expanding macroscopic system.
b.) Measure a phase transition, characterize the new phase, measure the de-excitation of the new phase into ‘ordinary’ matter – ‘do we come out the way we went in ?’
c.) Learn about hadronization  how matter is formed
(mechanism how quarks from hadrons
protons, neutrons, etc…)
Christina Markert Physics Workshop UT Austin April

16. How do we do heavy ion collisions in laboratory ?
We take an atom (Au)
We take away the electrons  ion
We accelerate the ion
We collide the ions and hopefully create the predicted quark gluon plasma in our
‘little bang’ (Au+Au)
Christina Markert Physics Workshop UT Austin April

17. Large Hadron Collider (LHC) at CERN
27 km
sNN= 7 TeV
v= %c
Christina Markert Physics Workshop UT Austin April
150 meters beneath the ground

18. Heavy Ion Physics at the LHC
Check the blog (

19. US ALICE – 13 Institutions 57 members (inc. 12+ grad. students)
ALICE Collaboration
~ 1000 Members (63% - CERN States)
~ Countries
~ 100 Institutes
US ALICE – 13 Institutions
57 members (inc. 12+ grad. students)
Cal. St. U. – San Luis Obispo, Chicago St. University, Creighton University, University of Houston, Lawrence Berkeley Nat. Lab, Lawrence Livermore Nat. Lab, Oak Ridge Nat. Lab, Ohio State University, Purdue University, University of Tennessee,
University of Texas at Austin, Wayne State University, Yale University
John Harris (Yale) for ALICE Collaboration Winter Workshop, Winter Park CO, 6 – 12 Feb 2011

20. most fundamental questions
ALICE :
A window to the
most fundamental questions

21. ALICE experiment at LHCcollider
(~1000 member)
Christina Markert Physics Workshop UT Austin April

22. Study all phases of a heavy ion collision
If the QGP was formed, it will only live for s !!!!
Christina Markert Physics Workshop UT Austin April

23. ALICE Experiment at the LHC Collider
Christina Markert Physics Workshop UT Austin April

24. Particle Tracks in the Detector
Head-on collision
~5000 charged hadrons (protons,…)
and leptons (electrons,..)
Christina Markert Physics Workshop UT Austin April

25. What can we measure ? a.) Which particles are produced ?
b.) How many are produced ?
c.) How are they arranged (angle)
d.) What does the theory tell us?
Christina Markert Physics Workshop UT Austin April

26. Heat and Compress Nuclear Matter-
We produce new quark-antiquark pairs: u u
Producing new matter out of Energy
Producing new quarks s,c,t,b which don’t exist
in ground state nuclear matter (neutrons+protons)
System expands new particles are produced:
Protons (uud) , anti-protons (uud) antimatter)
Lambdas (uds)
- - -
Christina Markert Physics Workshop UT Austin April

27. Questions we can answer
Quark Gluon Plasma:
Initial Temperature
Density
Viscosity
Equilibration time
Lifetime
Christina Markert Physics Workshop UT Austin April

28. Resonance Reconstruction in TPC
(1520) K- p
End view TPC
1/v 
p = mv (classical) p
relativistic momentum -
Christina Markert Physics Workshop UT Austin April

29. Finding Hadronic Resonance Particles
Undergraduate
students
in my group
Christina Markert Physics Workshop UT Austin April

30. Conclusions Data show evidence that we created a Quark Gluon Plasma
We have a phase transition proton -> quarks
Quark-gluon plasma lasts less than seconds
It is very dense and very hot
It behaves like a liquid not like a plasma
New experiment at larger Collider LHC at CERN to investigate properties of the ‘Quark Soup’
Christina Markert Physics Workshop UT Austin April

31. 1.Can we produce anti matter here on earth ?
Questions
1.Can we produce anti matter here on earth ?
2.Can we create matter out of energy ?
3.Is the proton the smallest building block
of nuclear matter ?
4.Can we accelerate particles up to nearly the
speed of light ?
5.Can we observe a single quark ?
Christina Markert Physics Workshop UT Austin April

32. 1.Can we produce anti matter here on earth ? Yes
Questions
1.Can we produce anti matter here on earth ?
Yes
2.Can we create matter out of energy ? Yes
3.Is the proton the smallest building block
of nuclear matter ? No (quark)
4.Can we accelerate particles up to nearly the
speed of light ? Yes
5.Can we observe a single quark ? No
Christina Markert Physics Workshop UT Austin April