A Taste of Things to Come Welcome to Physics Honours! W. A. Horowitz University of Cape Town February 11th, 2011 1/13/2019 UCT Honours

Four Fundamental Forces Electromagnetism Gravity starchild.gsfc.nasa.gov John Maarschalk, travelblog.portfoliocollection.com Weak Strong lhs.lps.org/staff/sputnam/chem_notes/tritium_decay.gif 1/13/2019 UCT Honours

Strong compared to E&M - + Electromagnetism Strong Electric charge (+) electrons Carriers: photons Field theory: Quantum electro-dynamics (QED) Strong Color charge (r, g, b) quarks Carriers: gluons Field theory: Quantum chromo-dynamics (QCD) - Hydrogen Look Inside + Proton nobelprize.org 1/13/2019 UCT Honours

High Energy Nuclear Physics is High Energy Gluon Physics Nucleus looks different at high E Nucleus becomes fatter with Energy E 1/13/2019 UCT Honours

Nucleus as a Function of Energy Measure the nuclear shape in e + A collisions E X-scn: Fourier Transform of Shape 1/13/2019 UCT Honours

What about Heavy Ion Physics? Measure many-body physics of strong force Test & understand theory of many-body non-Abelian fields Unique as compared to strongly coupled Abelian problems Long Range Plan, 2008 1/13/2019 UCT Honours

Heavy Ion Collisions Collider machines: RHIC, LHC Relativistic Heavy Ion Collider Large Hadron Collider 1/13/2019 UCT Honours

Big Bang vs. Little Bang t = - ¥ t = 0 t = 1 fm/c t = 3 fm/c ALICE Collaboration t = - ¥ t = 0 t = 1 fm/c t = 3 fm/c t = 4 fm/c t = + ¥ Initial State Initial Overlap Thermalization QGP Hadronization Hadron Gas 1/13/2019 UCT Honours

Orders of Magnitude Units: MeV, GeV At RHIC, nuclei acc. to 100 GeV per nucleon Energy of collision ~ two mosquitoes colliding Chaisson and McMillan, Astronomy Today (1993) Tc ~ LQCD ~ 200 MeV Temp. at RHIC ~ 10,000 times hotter than the core of the sun (15,000,000 Kelvin) www.answersingenesis.org 1/13/2019 UCT Honours

Experiments RHIC LHC BRAHMS PHENIX PHOBOS STAR ALICE ATLAS CMS LHCb 1/13/2019 UCT Honours

Evolution of a HI Collision T Hirano, Colliding Nuclei from AMeV to ATeV STAR 1/13/2019 UCT Honours

Why High-pT Jets? Tomography in medicine One can learn a lot from a single probe… and even more with multiple probes SPECT-CT Scan uses internal g photons and external X-rays PET Scan http://www.fas.org/irp/imint/docs/rst/Intro/Part2_26d.html 1/13/2019 UCT Honours

Tomography in QGP Requires well-controlled theory of: production of rare, high-pT probes g, u, d, s, c, b in-medium E-loss hadronization Requires precision measurements of decay fragments pT f , g, e- Invert attenuation pattern => measure medium properties 1/13/2019 UCT Honours

QGP Energy Loss Learn about E-loss mechanism Most direct probe of DOF AdS/CFT Picture pQCD Picture 1/13/2019 UCT Honours

Compare to Data Naively: if medium has no effect, then RAA = 1 1/13/2019 UCT Honours

LHC RcAA(pT)/RbAA(pT) Prediction Zoo of c and b Predictions: WAH, M. Gyulassy, PLB666 (2008) Taking the ratio cancels most normalization differences seen previously pQCD ratio asymptotically approaches 1, and more slowly so for increased quenching (until quenching saturates) AdS/CFT ratio is flat and many times smaller than pQCD at only moderate pT WAH, M. Gyulassy, PLB666 (2008) 1/13/2019 UT Colloquium

Research interests: Gary Tupper Particle physics Quantum field theory String theory & braneworld General relativity, Cosmology, Dark Matter & Dark Energy Unification of dark matter and dark energy: The Inhomogeneous Chaplygin gas. Neven Bilic, Gary B. Tupper, Raoul D. Viollier, (Cape Town U.) . Nov 2001. 10pp. Published in Phys.Lett.B535:17-21,2002. e-Print: astro-ph/0111325 TOPCITE = 250+ Cited 424 times Transport modelling in industrial mills 1/13/2019 UCT Honours

Most of the stuff in the universe is nonluminous Overall picture today: Particle Dark Matter? Cosmological Constant Dark Energy? 1/13/2019 UCT Honours

Tumbling Mills Minerals industry (gold, platinum, copper, etc …) 1st stage of above ground mineral beneficiation Size reduction Expose valuable mineral 15% of power consumption in SA 60% of operation cost Models are empirical Cannot extrapolate Mill specific Ore specific 1/13/2019 UCT Honours

PUBLICATIONS: See http://www.slac.stanford.edu/spires/hep/ PhD STUDENTS (UCT) 2011: Sebastian Bodenstein (1st year), Preshin Moodley (1st year), and Yingwen Zhang (2nd year). Fellowships from RSA National Institute for Theoretical Physics (NITheP).   INTERNATIONAL COLLABORATIONS: with colleagues from the universities of Mainz (Germany), Valencia (Spain), Mexico, Chile, and Argentina. Graduate students participating and visiting these institutions on a yearly basis. SUMMER SCHOOL, ICTP (TRIESTE): Graduate students attending yearly summer school at ICTP (International Centre for Theoretical Physics) thanks to Federation Arrangement. PUBLICATIONS: See http://www.slac.stanford.edu/spires/hep/ Under author C DOMINGUEZ. Emer. Prof. Cesareo A. Dominguez, UCT & SUN RESEARCH: Quantum Chromodynamics (QCD), in particular determination of the fundamental QCD parameters: quark-gluon coupling and quark masses. Non-perturbative effects in QCD due to confinement. QCD sum rules. QCD at finite temperature and density, and connection with quark-gluon plasma studies, quark and gluon deconfinement, etc. Relation to experiments at BNL and LHC. Quantum Electrodynamics (QED): nonlinear effects due to quantum fluctuations in the QED vacuum. Prediction of new phenomena, and design of experiments to measure them, e.g. neutron scattering off nuclei, and high intensity laser experiments. 1/13/2019 UCT Honours

Monte Carlo Modeling Model of proton therapy beam line [Dr. Steve Peterson] Model of proton therapy beam line Positron path Calculating positron range Designing a 3-stage Compton camera 1/13/2019 UCT Honours

Image Reconstruction [Dr. Steve Peterson] Capturing scattered prompt gammas from proton beam in 3-stage Compton camera Overlap of back-projected cones to reproduce source 1/13/2019 UCT Honours

Let’s Eat! 1/13/2019 UCT Honours