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Lessons from the cosmos Earth based experiments Discoveries and new challenges Towards the most fundamental questions Black Holes and the Universe – How the LHC re-creates the beginning of time Rene Bellwied Wayne State University ([email protected]) Cosmic wave background map A public lecture T in the universe: 3 K = -454oF Matter in the universe A 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 > 90% of the mass in the universe. Dark Matter vs. Luminous Matter distribution Bullet 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 Dark and visible matter are close together ? Formed in same process ? Matter in the Universe Before 1911, the atom was thought to be the most fundamental form of matter! Matter in the Universe 1911 – atomic nucleus discovered by E. Rutherford Atom 100 trillionths (10-10) meter Electrons orbiting nucleus Matter in the Universe Electrons orbiting nucleus 1919 – atomic nucleus contained protons (1932 – and neutrons) Atom Atomic nucleus .01 trillionths (10-14) meter Matter in the Universe 1974 – “elementary” particles made up of quarks & gluons Electrons orbiting nucleus Atom 100 trillionths (10-10) meter Atomic nucleus .01 trillionths (10-14) meter Neutrons & Protons .001 trillionths (10-15) meter quarks (also gluons!) Stars are moving : Doppler Effect with Stars A star's motion causes a wavelength shift in its light emission spectrum, which depends on speed and direction of motion. If star is moving toward you, the waves are compressed, so their wavelength is shorter = blueshift. If the object is moving away from you, the waves are stretched out, so their wavelength is longer = redshift The spectral lines of nearly all of the galaxies in the universe are shifted to the red end of the spectrum. This means that the galaxies are moving away from the Milky Way galaxy. Evidence for the expansion of the universe. uniform expansion = Hubble law Age of universe = 1/H0 Let’s go back in time to when matter was formed – but how ? It’s -454oF out there now Assume that the universe expands homogenously and simply run the expansion backwards (compression) at a compression rate set by the Hubble constant Volume goes down Pressure goes up Temperature goes up Energy goes up Going back in time… phases of matter form whenever energy is low enough for them to survive Age 0 Energy 1019 GeV Matter in universe grand unified theory of all forces 10-35 s 1014 GeV 1st phase transition (strong: q,g + electroweak: g, l,n) 10-10 s 10-5 s 102 GeV 0.2 GeV 2nd phase transition LHC-HEP (strong: q,g + electro: g + weak: l,n) 3rd phase transition protons/neutrons RHIC & LHC-NP 0.1 MeV nuclei FRIB & FAIR (strong:hadrons + electro:g + weak: l,n) 3 min. 6*105 years 0.3 eV atoms Now 3*10-4 eV = 3 K (13.7 billion years) 13.7 billion yrs Evolution of Matter in the Universe 1 billion yrs 380,000 yrs 3 min. 10-5 sec. 10-43 seconds BIG BANG T ~ 1032 K Quarks & Gluons (T=1012 K) Particles Atomic Nuclei Atoms (3,000 K) Galaxies (3 K) Man The 4 Forces of Nature Gravitational force – attractive force between objects of matter Electromagnetic force – force between electrically charged objects Weak nuclear force – force that causes transmutation of nuclei Strong Nuclear Force – force that keeps nuclei together – force that holds quarks (and gluons) inside protons & neutrons Mass puzzle: p/n believed to contain three quarks, but mp = 1.67*10-27kg and mq= 9*10-30kg, so 3mq = mp. Where does all the mass come from ? Forces get weaker with distance…..except to study structure of an atom… electron …separate constituents nucleus F ~ 1/r2 Imagine our understanding of atoms or QED if we could not isolate charged objects!! neutral atom ToConfinement: understandfundamental the strong force and the phenomenon of confinement: & crucial (but not understood!) feature of strong force - colored objects (quarks) have energy in normal vacuum Create and study a system of deconfined colored quarks (and gluons) quark-antiquark pair created from vacuum quark “white” proton (confined quarks) Strong color field “white” 0 “white” proton Force grows with separation(confined !!! quarks) F~r Force between two quarks quark gluons quark Compare to gravitational force at Earth’s surface Quarks exert 16 metric tons of force on each other! Making ‘Quark-Gluon Soup’ How to do it ? Instead of pulling particles apart: • heating • compression ‘free’ quarks and gluons needs a trillion (!) degrees (30,000 times the Sun’s Temp) instead of heating how about banging together ? Hadronic Nuclear Matter Matter Quark Gluon Plasma (confined)! deconfined The Relativistic Heavy Ion Collider 3.8 km circle PHOBOS PHENIX RHIC BRAHMS STAR AGS TANDEMS Gold nuclei each with 197 protons + neutrons are accelerated The STAR Experiment The STAR Experiment ~ 540 collaborators 44 institutions 8 countries Cost for RHIC: ~ $550 Million Cost for STAR: ~ $50 Million Took 10 years to build Brazil: Sao Paolo England: Birmingham Germany: Frankfurt, MPI - Munich U.S.: China: IHEP - Beijing, IPP - Wuhan France: Poland: Russia: IReS - Strasbourg, SUBATECH-Nantes Warsaw University, Warsaw U. of Technology MEPHI - Moscow, JINR - Dubna, IHEP - Protvino Argonne, Berkeley, Brookhaven National Laboratories UC Berkeley, UC Davis, UCLA, Creighton, Carnegie-Mellon, Indiana, Kent State, MSU, CCNY, Ohio State, Penn State, Purdue, Rice, Texas, Texas A&M, Washington, Wayne, Yale Universities Geneva with Large Hadron Collider Superimposed First beam in 2009 Heavy Ion Physics at the LHC ALICE : A window to the most fundamental questions (1100 scientists, 250 Million Dollars, 12,500 tons, 15 years to build) 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 ??? 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 ??? We are forming a fireball of a new medium (free quarks and gluons) which will de-excite (explode) into many, many particles (600 on 600 quarks gives you nearly 10,000 new particles – (Einstein at its best)) What are the properties of this phase ? How does it convert back to ordinary matter ? Is anything else produced ? Size of fireball: ~ 10x10x10 fm So what do we hope for ? 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. 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 went in ?’ b.) How do the particles (ordinary matter) form ? How do they attain their mass ? c.) Does Dark Matter form at the same time ? d.) Do Black Holes form ? Are they related to Dark Matter or Dark Energy ? e.) Does matter separate from anti-matter ? It’s news all over the world USA Today: The Great Fear of the Unknown Malaysia Sun: Large Hadron Collider could spell doomsday for the Earth in nine days ! MSNBC: Atom smasher fears spark lawsuit Fox news: ‘World-ending machine’ slated to go online soon Spiegel (Germany): Black holes in Geneva: Is this the end of the world ? The Black Hole scare At the LHC we think we can either make black holes on the scale of the proton or make objects that have quantum properties like a black hole but are not actual black holes (quantum black holes) Is that dangerous ? Absolutely not As we all know a black hole grows by absorbing the surrounding matter. But in order to have that ‘attractive’ force a black hole must have a minimum size, i.e. the size of an atom (~10-10m). The proton is 10-15m, so about 100,000 times too small. There will never be enough energy to make a black hole big enough for it to be dangerous. Luckily our instruments are so sophisticated that we can learn a lot from our mini or quantum black holes. In addition natural high-energy cosmic rays bombard the earth daily for Billions of years now and cause collisions at significantly higher energies than the LHC can produce. So yes we want to make them, and no they are not threatening !! Measuring particles The basic principle: measure every particle that leaves a track in the detector. • Only charged particles lose energy when traversing the detector (ionization of gas). From the amount of energy loss and the time it takes to traverse the detector volume we can determine the mass of the particle. • Detector is in magnetic field. From the bending of the track in the field we can determine the momentum and velocity of each particle. Probing the medium with fast particles idea: use p+p collisions (no medium) as reference p p ?: what happens in Au+Au to particles which pass through medium? Prediction: density in fireball is so high that particles get stuck. Measure properties of medium from the interaction of particles with medium. ? Au+Au High momentum particles get stuck ! STAR, nucl-ex/0305015 pQCD + Shadowing + Cronin energy loss pQCD + Shadowing + Cronin + Energy Loss The system is very dense. Too dense to be made of protons and neutrons ! SYSTEM NEEDS TO BE MADE OF QUARKS & GLUONS The deposited energy density is enormous, at least 5 GeV/fm3 The energy density is 5 GeV/fm3. Is that a lot? Last year, the U.S. used about 100 quadrillion BTUs of energy: At 5 GeV/fm3, this would fit in a volume of: Or, in other words, in a box of the following dimensions: Collective motion of the matter constituents: The medium is deconfined and consists of quarks 2q-states (mesons) 3q-states baryons baryons mesons RHIC discoveries (2000 – 2010) The ‘Perfect Liquid’ (2005) based on strong collective flow z y x RHIC discoveries (2000 – 2010) The ‘Hottest State’ (2010) based on photon radiation 4 Trillion Degrees = 400 MeV = 2 Tc Lessons from RHIC: The Quark Soup AIP Science Story of 2006 The early universe behaves like a liquid not like a gas or plasma Where are we ? We created a new phase of matter, made of quarks, which existed only microseconds after the Big Bang. Surprisingly that phase behaves like a liquid rather than a gas or a plasma We are starting to understand the creation of matter in the universe. Where are we going ? Collectivity causes correlations Heavy-ion Collisions: Rapid Expansion collision evolution The Universe: Slow Expansion particle detectors expansion and cooling kinetic freeze-out lumpy initial energy density hadronization distributions and correlations of produced particles QGP phase quark and gluon degrees of freedom credit: NASA collision overlap zone ~ 0 fm/c quantum fluctuations 0~1 fm/c ~ 10 fm/c particle distribution in h and f The future is bright The LHC: higher energy collisions, bigger and better detectors On to: black holes, dark matter, Super-symmetry, extra-dimensions, Higgs fields and parallel universes Already.... An amazing journey !! November 2009: 900 GeV collisions (450 on 450 GeV) December 2009: 2.36 TeV collisions (11.8 on 1.18 TeV) March 2010: 7 TeV collisions (3.5 on 3.5 TeV) Highest energy planned: 14 TeV (in 2012) Highest energy prior: 1.8 TeV at FNAL Welcome to the new age !