From the Big Bang to the Mini Bang and back!! Prof. Claude Pruneau October 31, 2016.

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1 Wayne State University College of Liberal Arts & Sciences Department of Physics and Astronomy From the Big Bang to the Mini Bang and back!! Prof. Claude Pruneau October 31, The mini-bang: How studies at the CERN Large Hadron Collider inform us about the Big Bang! 1

2 A little bit of context 25 galaxies 1929: E. Hubble discovers Redshift Distance Law, now known as Hubble's law Expansion of the Universe 2

3 Big Bang Theory ~14 billion years ago, the portion of the universe we can see today was only a few millimeters across. It has since expanded from this hot dense state into the vast and much cooler cosmos we currently inhabit. Three Pillars of the Big Bang Theory Expanding Universe Cosmic Microwave Background Cosmic Elemental Abundances 3

4 So many galaxies Hubble Ultra Deep Field September 24, 2003 January 16, arcminutes 2.4 arcminutes ~10,000 galaxies Exposure: ~10 6 seconds 4

5 So much mass, so much energy Sun:1.989x10 30 kg billion stars 100 kly Milky Way: M = 2x10 42 kg ~50 galaxies Local Group: M = 2x10 42 kg >100 galaxy groups Local Supercluster: 2x10 44 kg Laniakea Supercluster ~ 100,000 galaxies clusters 520 Mly 2x10 49 kg 5

6 Early Universe Temperature: GeV Did matter as we know it exist then? What is matter made of anyway? 6

7 What is matter made of? Philosophers have tried to answer this question for a long time! The Greeks of the Antiquity 5th century BCE, Leucippus & Democritus: All matter is composed of small indivisible particles called atoms (indivisible) 7

8 Some of the Scientists who discovered what matter is made of? John Dalton ( ), Elements always react in ratios of small whole numbers Robert Brown ( ), Observation of Brownian Motion Albert Einstein ( ), Motion of atoms explains Brownian Motion (Nobel 1921) J. J. Thompson ( ), Discovery of the electron (Cathode rays) (Nobel 1906) Hans Geiger, Ernest Marsden, Ernest Rutherford ( ): Discovery of the Atomic Nucleus (Nobel 1908) James Chadwick ( ), Discovery of the neutron (Nobel 1935) Niels Bohr ( ), Atomic structure and Quantum Theory (Nobel 1922) Louis de Broglie ( ), Wave nature of electrons (Nobel 1929) Erwin Schrödinger ( ), Development of Quantum Theory (Nobel 1933) Werner Heisenberg ( ), Development of Quantum Mechanics (Nobel 1932) Otto Hahn ( ), Discovery of Nuclear Fission (Nobel 1944) w/ Lise Meitner ( ), Otto Frish 8

9 What is matter made of? Based on electronic structure Dmitri Mendeleev ( ) and a few more 9

10 Some of the Scientists who discovered what matter is made of (cont d)? Wolfgang Ernst Pauli ( ), Pauli Exclusion Principle, Theory of Spin (Nobel 1945). Paul A. M. Dirac ( ), Predicted existence of anti-matter (1933). Emilio G. Segrè ( ), Owen Chamberlain ( ) Discovery of anti-proton (Nobel 1959). Hideki Yukawa ( ), Theory of mesons (Nobel 1949). C. F. Powell ( ), Discovery of the pion (Nobel 1950). G. D. Rochester ( ), C. C. Butler ( ), Discovery of the Kaon. T. D. Lee ( ), C.N. Yang ( ), Parity Violation (Nobel 1957). R. Feynman ( ), Parton Model, Field Theory (Nobel 1965). S. Glashow ( ), S. Weinberg, A. Salam, Electroweak Theory (Nobel 1979). B. Richter, S. Ting, Discovery of Charm (Nobel 1976). Makoto Kobayashi ( ), Toshihide Maskawa (), CP Violation, Broken Symmetries, Prediction Bottom & Top Quark (Nobel 2008). Leon Lederman ( ), Discovery of Bottom Quark, Neutrino (Nobel 1988). CDF and DO Collaborations, Fermilab, Discovery of Top Quark. Peter Higgs ( ), François B. Englert ( ), Broken symmetry, Higgs Mechanism (Nobel 2013). CMS and ATLAS Collaborations, LHC, CERN, Discovery of the HIGGs Boson. 10

11 Structure of Matter Quark Model: First developed by Murray Gell-Mann Murray Gell-Mann ( ) Nobel 1969 Quark: nonsense word taken from Joyce s Finnegan s Wake. Nuclear Physics: Study of nuclear force, nuclear structure, phases of nuclear matter. Particle Physics: Study of elementary forces and particle structure. 11

12 Elementary & Not So Elementary Particles After > 75 years of Nuclear & Particle Physics Composite Particles: Hadrons Baryons (Fermions) Mesons (Bosons) Elementary Particles Fermions Leptons Quarks Particle Data Book ~1500 pages Bosons Photon W & Z Boson Gluon Higgs Boson 12

13 Four Fundamental Forces 13

14 Strong Nuclear Force Acts between Quarks (and nucleons) Modern Theory: Quantum Chromodynamics Mediated by Gluons (mass = 0, spin = 0) Gluons carry a charge named color (rgb) Quarks combined as triplets (Baryons) or pairs (Mesons) 14

15 Quark Gluon Plasma A phase of matter such that quarks are not confined to a small volume, e.g. that of a proton. (Possibly) obtained by heating nuclei at very high temperature!!! Quark Gluon Plasma 15

16 Phase Transitions & Phase Diagrams Phase Diagram of H2O 16

17 Phase Diagram of Nuclear Matter 17

18 Energy Density/T 4 Hadron-QGP Phase Transition Temperature (MeV) 18

19 How to create a Quark Gluon Plasma! 19

20 How to create a Quark Gluon Plasma! RHIC & LHC Collisions Quark-Gluon Plasma Key Quarks Gluons 20

21 How to produce/observe the Quark Gluon Plasma! Relativistic Heavy Ion Collider STAR PHENIX Large Hadron Collider ALICE 21

22 A closer look at RHIC & LHC RHIC Circumference: km 1,740 superconducting dipole magnets (niobium-titanium conductors) T = 3.45 K. Protons: 250 GeV protons; Gold: 200 GeV/A 6 interaction points LHC Circumference: 27 km 1232 superconducting dipole magnets Two apertures, 14.3 m long; 35 tonnes T = 1.9 K; Current: 11,850 A B-field: 8.3 T; Cost: ~ 0.5 million CHF each Protons: 7 TeV Lead: 2.5 TeV/A Total stored energy in magnets = 11GJ m underground. 22

23 Relativistic Nucleus-Nucleus Collisions RHIC:14/200 fm LHC: 14/2700 fm t <20 fm/c 14 fm Approach Beam energy RHIC: 200 GeV/A LHC: 2.73 TeV/A Special Relativity - Spatial Contraction Collision Medium (QGP) Formation &Expansion Hadronization Particle Free Streaming up to 6000 particles produced!!! Note: 1 fm = m; 1 fm/c = m/3x10 8 m/s = 0.33x10-23 s 23

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25 Time Evolution of Nucleus-Nucleus Collisions 25

26 Alice Detector 26

27 Particle Identification TOF 150 k channels 90 ps resolution 27

28 Collision Snapshots ALICE Au + Au nucleus collision at 200 GeV/nucleon Pb + Pb nucleus collision at 2.7 TeV/nucleon 28

29 Measuring Heavy Ion Collisions Detect particles Record information: Reconstruct what happened Analyze data Grid Computing Data volume: 1 collision = ~1 MB Storage: > 50 PB 1000s of CPUs 29

30 Flow Coordinate Space Anisotropy Momentum Space Anisotropy Picture: UrQMD X Z XZ the reaction plane 30

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32 First Flow Observations at RHIC S 32

33 May

34 Flow Observation at RHIC (2) Quark Scaling S 34

35 Flow at ALICE/LHC Equation of State, Viscosity 35

36 Jets in Heavy Ion Collisions Un-attenuated Jet Au Au Attenuated Jet 36

37 37

38 Jets in Pb Pb Collisions? 38

39 Particle Production Cross Section S Strong Absorption Opaque Medium 39

40 Nuclear Modification Factor S 40

41 Evidence for Jet Interactions with the Medium in A + A The Discovery Plots Evidence from d+au measurements for final-state suppression of high pt hadrons in Au+Au collisions at RHIC. Phys. Rev. Lett. 91 (2003) Binary collision scaling p+p reference Production of particles at high pt highly suppressed in Au+Au Production of particles on the away side also highly suppressed in Au + Au. But not d+au, implies suppression happens due to the collision. Strong evidence for high pt parton (jets) interaction with the medium!! 7/18/13 4 < p T trig < 6 GeV/c p T asso > 2 GeV/c See also: PHENIX, Phys. Rev. Lett. 88, (2002), Phys. Rev. Lett. 91, (2003); Phys. Rev. C 69, (2004) pqcd-i: Wang, nucl-th/ ; pqcd-ii: Vitev and Gyulassy, PRL 89, ; Saturation: KLM, Phys Lett B561, 93 41

42 Wayne State University College of Liberal Arts & Sciences Department of Physics and Astronomy High Energy Nuclear Research Nuclear Physics at High Energy 4 Experimental Faculty + 2 Theoreticians, many research postdocs, many graduate students Participation in LHC/ALICE, BNL/STAR experiments. Many Research Topic Study of the Quark Gluon Plasma, its equation of state and its properties. Study of fundamental symmetries of matter 42

43 Research Topics in Heavy Ion Probing the Properties of the QGP Equation of state i.e., the equivalent of pv=nrt Viscosity Heat Capacity Electric Conductivity Vorticity, PolarizationP Parton Transport Properties Understanding the evolution of the QGP and its dynamics Thermalization Time How harmonization work? Dynamics of charged particle creation Jet Medium Interaction Probing QCD Properties Search for the Chiral Magnetic Effect (Local Parity Violation) Jet Structure and Substructure