The Big-Bang Machine Stefan Spanier Physics and Astronomy University of Tennessee, Knoxville 1 25 February 2017 Stefan Spanier, The Big Bang Machine
Accelerator = Microscope Length to be resolved L L � 1/Particle Energy Pocket Electron-Accelerator Energy - - + 2 25 February 2017 Stefan Spanier, The Big Bang Machine
Particle Collider Experiment Principle Particle Accelerator Very High Voltage provides large (year 1932) kinetic energy E = m c 2 short lived particle – new matter? Particles live long enough to make signals in a detector (material) - create light - generate new particles 3 25 February 2017 Stefan Spanier, The Big Bang Machine
Particle Collider Experiment Principle Measure many particles e.g. their energy … more like exists ~10 -23 seconds Background Signal Lifetime � 1 / Width 4 25 February 2017 Stefan Spanier, The Big Bang Machine
The Standard Model Building Blocks Proton _ _ u d d u Latest addition 1995 _ Tevatron at Fermilab u u Anti-proton hadrons particles anti-particles _ _ _ Quarks u c t d s b _ _ _ d s b u c t _ _ _ e - � � �� � � e � � � � Leptons e + � � � � � e � � � � mass 5 25 February 2017 Stefan Spanier, The Big Bang Machine
Particles and Forces + + - + 2 Charge Force � 2 Distance Coulomb law, 1783 Franklin, June 1752 Electric Force : same sign electrical charges repel each other even at infinite separation Electromagnetic Force : Unification electricity+magnetism Maxwell ~1861 6 25 February 2017 Stefan Spanier, The Big Bang Machine
Particle Interactions Particle Physics ( Quantum Field Theory) Started ~ 1925 Time Photon virtual photon Coupling + + to Charge � � � � 1 Mass 0 Range Photon � Range Mass � Theory works extremely well Boson precision within ten parts in a billion 7 25 February 2017 Stefan Spanier, The Big Bang Machine
Particle Interactions 8 25 February 2017 Stefan Spanier, The Big Bang Machine
Particle Interactions Radioactive Decay � Weak Force ~10 -15 m ~10 -18 m e - u e - W - d � � Neutron � Proton 1 � Mass ~ 80 � Mass Proton � W Range Mass Could the forces be the same? Boson What is the underlying important principle? 9 25 February 2017 Stefan Spanier, The Big Bang Machine
Standard Model Fundamentals The SM is a Quantum Field Theory: describes all interactions as exchange of particles 1) Force laws must apply at all places and times � gauge invariance (know how to calibrate) 2) Predicted reaction rates should be finite at all energies � renormalizable Turns out: Theories based on principle 1) deliver predictions with high precisions But: To work everywhere the force particles need to be massless !!! 10 25 February 2017 Stefan Spanier, The Big Bang Machine
Noble Price 2013 11 25 February 2017 Stefan Spanier, The Big Bang Machine
The Higgs Mechanism How particles acquire masses … The Higgs particle mass generation � Standard Model safe ! ???? 12 25 February 2017 Stefan Spanier, The Big Bang Machine
Why should it be safe? The Standard Model has ~ 18 (+9) dials (parameters) that are adjusted in agreement with measurements - precisely They are not a fundamental outcome of the present theory = appear to be arbitrary settings - could be linked Arbitrariness is Ignorance – we do not know yet the more fundamental theory – what is it? 13 25 February 2017 Stefan Spanier, The Big Bang Machine
Standard Model in Everyday Life e.g. the W-boson controls the Sun � this weak force process starts the cycle that fuels the Sun: p e + p n p Deuterium � Set W mass dial to lower value � Sun hotter, brighter � more UV light W mass is given by Higgs interaction, but not its value 14 25 February 2017 Stefan Spanier, The Big Bang Machine
The Time Machine 15 25 February 2017 Stefan Spanier, The Big Bang Machine
Time 1 meV Today ( T= 2.7 K ) ~ 13.7 billion years The Bigger Picture – if this is it … Solar system Galaxy formation 400,000 yr 1 s Nuclei form (D, He, Li) 10 -8 s Quark � protons, neutrons form 10 3 GeV Higgs acts Why here? 10 -12 s LHC Particle Desert: Are there more particles ? 10 15 GeV Unification of electroweak 10 -35 s and strong force 10 -43 s 10 19 GeV Planck Epoch ( T~10 32 K ) Big Bang 16 25 February 2017 Stefan Spanier, The Big Bang Machine
Grand Unification of Forces Minimal Supersymmetric SM � develop new theories, e.g. Supersymmety ? Simplest super-symmetric model has 105 dials … 17 25 February 2017 Stefan Spanier, The Big Bang Machine
The Experiment Smash things together and see what happens! 18 25 February 2017 Stefan Spanier, The Big Bang Machine
How to produce particles at LHC? Proton Collision u d u d u d Proton u u d d u d b d u b d Proton u d d Higgs, X, Y … b b 19 25 February 2017 Stefan Spanier, The Big Bang Machine
Higgs Hunt ? How do you find one Higgs? If each person is one collision event you need to search ~100 times the number of people on Earth In 2017 there are 7.5 billion people on Earth! Because you need several Higgs and you will miss some you need to do this over an over. 20 25 February 2017 Stefan Spanier, The Big Bang Machine
LHC at CERN Mont Blanc The Higgs Mechanism Airport CERN CMS CMS LHC control room http://www.lhc-closer.es/1/3/10/0 21 25 February 2017 Stefan Spanier, The Big Bang Machine
LHC Storage Ring LINAC Need injector, since magnetic field Magnet cannot start from zero. Beam broken up into bunches RF ~ 3000 bunches in LHC ~ 100 billion protons/bunch 22 25 February 2017 Stefan Spanier, The Big Bang Machine
The LHC Protons The bottle with hydrogen gas (the protons) ~ 12 liters of gas compressed (1 gram of gas) Airport CERN How often does it need to be refilled? In a year 8 months/year x 120 fills/month x 3 * 10 14 protons/fill 17 protons ~ ~ 3 3 * 10 10 17 protons / / year year In the bottle are ~6 * 10 23 protons � The bottle lasts for 2 Million years ! 23 25 February 2017 Stefan Spanier, The Big Bang Machine
LHC RF Cavity Acceleration to full energy takes 20 minutes. 24 25 February 2017 Stefan Spanier, The Big Bang Machine
PS Accelerator Section 25 25 February 2017 Stefan Spanier, The Big Bang Machine
LHC in LEP tunnel LHC Superconducting magnets: • 1232 dipole magnets (bending) - T = -271 o C (superfluid Helium) - 100,000 x earth magnetic field superconducting dipole magnet Each beam • Circulation time: 89 � s • Current: ~ 0.6 Ampere • Time between collisions: 25 ns • Fill time (450 GeV): 7.5 min • Acceleration time : 20 min • Beam lifetime : several hours 26 25 February 2017 Stefan Spanier, The Big Bang Machine
Beam Protection Energy stored/beam: 360 MJ Energy stored in magnets: 700 GJ • The energy per proton is equivalent to using ~70,000 Hiroshima bombs (‘Little Boy’) to accelerate a 22 caliber bullet. • The energy stored in the beam is equivalent to a small aircraft carrier of mass 10,000 tons traveling at 20 miles/hour. • This energy can lighten up a 100W light bulb for 1000 hours. Beam loss is fatal: copper plate 450 GeV beam 10 20 60 40 bunches 27 25 February 2017 Stefan Spanier, The Big Bang Machine
Develop Diamond Detectors Prototype diamond pixel detector Prototype diamond pixel detector readout at UTK (SERF) readout at UTK (SERF) using radioactive sources using radioactive sources Installation of diamond diode detectors Installation of diamond diode detectors near the beam pipe in the CMS detector near the beam pipe in the CMS detector to continuously monitor the beams in the to continuously monitor the beams in the CMS detector region CMS detector region 28 25 February 2017 Stefan Spanier, The Big Bang Machine
How to detect the Higgs? Every 25ns protons in bunches collide Interactions/crossing = 25 (~1000 charged particles) Simulation in 100,000x earth magnetic field Higgs + 25 other events � + � - p Higgs Higgs p Z � + � - In CMS collision information corresponds to 100 billion phone calls per second. 29 25 February 2017 Stefan Spanier, The Big Bang Machine
The LHC Collaboration About 10,000 of Earth’s inhabitants came together to make it happen. 30 25 February 2017 Stefan Spanier, The Big Bang Machine
The CMS Detector Superconducting coil -270 o C Charged Particle Tracker Photon and Electron Detector Width: 22m Muon Detectors Diameter: 15m Weight: 13,000 tons Iron return yoke Weighs ~25% more than the Eiffel Tower in Paris 31 25 February 2017 Stefan Spanier, The Big Bang Machine
The first force studied carefully by CMS was Gravity … The first force studied carefully by CMS was Gravity … 32 25 February 2017 Stefan Spanier, The Big Bang Machine
The CMS Collaboration 33 25 February 2017 Stefan Spanier, The Big Bang Machine
The CMS Detector Superconducting Solenoid Hadron Calorimeter E/M Calorimeter [scintillators & brass] All Silicon Tracker (Pixels and Microstrips) Muon System 34 25 February 2017 Stefan Spanier, The Big Bang Machine
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