1. Abigail Bickley, Dept of Chemistry, July 25, 2008 Large Hadron Collider

2. July 25, 2008Abigail Bickley, PAN 20082 Where is the LHC?

3. July 25, 2008Abigail Bickley, PAN 20083 Where is the LHC? Switzerland France Circumference: 27km = 16.8miles

4. July 25, 2008Abigail Bickley, PAN 20084 Where is the LHC?

5. July 25, 2008Abigail Bickley, PAN 20085 Deconstructing a Name Collider: –Two beams of particles circulate in opposite directions around the ring –Beams intersect at 4 locations –These locations are where the collisions occur and are observed by warehouse sized detectors Hadron Large

6. July 25, 2008Abigail Bickley, PAN 20086 Deconstructing a Name Collider Hadron: –General category for the type of particles accelerated (protons and heavy nuclei) –Hadrons (from the Greek ‘adros’ meaning ‘bulky’) are particles composed of quarks. The protons and neutrons that atomic nuclei are made of belong to this family. On the other hand, leptons are particles that are not made of quarks. Electrons and muons are examples of leptons (from the Greek ‘leptos’ meaning ‘thin’). Large 10 -10 m u u d 10 -15 m10 -9 m

7. July 25, 2008Abigail Bickley, PAN 20087 Deconstructing a Name Large: –The size of an accelerator is related to the maximum beam energy obtainable. –This is a function of the radius of the machine and the strength of the dipole magnetic field that keeps particles in their orbits. –The LHC re-uses the 27 ‑ km circumference tunnel that was built for the previous big accelerator, LEP. –The size of the tunnel, magnets, cavities and other essential elements of the machine, represent themain constraints that determine the design energy of 7 TeV per proton beam.

8. July 25, 2008Abigail Bickley, PAN 20088 Colliders vs Cyclotrons Cyclotrons: –Produces a single beam of ions that are directed towards a stationary target –Maximum beam energy is dependent upon the radius of the cyclotron Colliders: –When two beams collide, the energy of the collision is the sum of the energies of the two beams. –A beam of the same energy that hits a fixed target would produce a collision of much less energy.

9. July 25, 2008Abigail Bickley, PAN 20089 Recipe for Creating an Ion Beam 1Ion Source: –All protons accelerated at CERN are obtained from standard hydrogen. –Protons are isolated by stripping orbiting electrons off of hydrogen atoms. –Although proton beams at the LHC are very intense, only 2 nanograms of hydrogen are accelerated each day. –It would take the LHC about 1 million years to accelerate 1 gram of hydrogen.

10. July 25, 2008Abigail Bickley, PAN 200810 Recipe for Creating an Ion Beam 2Multi-Stage Acceleration: –The accelerator complex is a succession of machines with increasingly higher energies. –Each machine injects the beam into the next one, which brings the beam to an even higher energy. 0.050 GeV 1.4 GeV 25 GeV 450 GeV 7000 GeV

11. July 25, 2008Abigail Bickley, PAN 200811 Recipe for Creating an Ion Beam 3LHC = Final Acceleration –Protons at full energy in the LHC will be traveling at 0.999999991 times the speed of light. –Each proton will go round the 27 km ring more than 11,000 times a second. –Entire acceleration process takes ~30min

12. July 25, 2008Abigail Bickley, PAN 200812 Recipe for Creating an Ion Beam 4Collision Tuning: –Beam is produced in “bunches” not a continuous stream of particles. –A filled ring contains 2808 bunches. –Each bunch contains 1.1x10 11 protons –Arrival of bunches from both beams at the interaction region must be timed perfectly to create collisions –600M collisions per second

13. July 25, 2008Abigail Bickley, PAN 200813 Power Consumption Annual operation requires 800,000 MWh Equivalent to the entire state of Geneva Machine only operates 270 days/year Cooling of the superconducting magnets consumes the majority of the power (9593 total magnets) Electricity is provided by France –20% of French electricity is generated in nuclear power plants

14. July 25, 2008Abigail Bickley, PAN 200814 CERN Price Tag Annual energy cost: $30M Construction Costs PersonnelMaterialsTotal Facility$890M$3550M$4,440M Injector$87M$67M$154M Computing$87M $174M Total$1,064M$3,704M$4,768M

15. July 25, 2008Abigail Bickley, PAN 200815 Existing Colliders/Accelerators FacilityLocationMax Energy SpeciesScience LHCFrance & Switzerland 7 TeV 2.76 TeV/u Proton Lead Higgs, Super Symmetry, etc RHICBrookhaven, NY200 GeVProton, GoldQuark Gluon Plasma TevatronBatavia, Il1 TeV(Anti)-ProtonTop quark CEBAFNewport News, VA4 GeV (12 GeV) ElectronsNucleon sub- structure RHIC from space

16. July 25, 2008Abigail Bickley, PAN 200816 Why Collide Nuclei?

17. July 25, 2008Abigail Bickley, PAN 200817 Evolution of the Universe LHC equivalent to t = 10 -25 seconds. As time progressed the universe expanded and cooled. Free quarks and gluons became confined.

18. July 25, 2008Abigail Bickley, PAN 200818 The Particle Zoo The nucleus of an atom is composed of protons & neutrons But these particles also have a quark substructure –Proton = uud –Neutron = udd The antimatter equivalent to the proton is the antiproton (uud) Proton

19. July 25, 2008Abigail Bickley, PAN 200819 The Particle Zoo QuarkChargeMass Up+2/31.9 MeV Down-1/34.4 MeV Strange-1/387 MeV Charm+2/31.32 GeV Bottom (Beauty) -1/34.24 GeV Top (Truth) +2/3172.7 GeV

20. July 25, 2008Abigail Bickley, PAN 200820 Scientific Goals of LHC: Higgs Boson The Higgs boson is a hypothesised particle which, if it exists, would give the mechanism by which particles acquire mass. Referred to in the lay press as the “God particle” Higgs proposed that the whole of space is permeated by a field, similar in some ways to the electromagnetic field. As particles move through space they travel through this field, and if they interact with it they acquire what appears to be mass. This is similar to the action of viscous forces felt by particles moving through any thick liquid. the larger the interaction of the particles with the field, the more mass they appear to have. Force carrier of the Higgs field is the Higgs boson. ‘Well, either we've found the Higgs boson, or Fred's just put the kettle on’ http://www.oufusion.org.uk/newssummer01/fusionnewssummer01.htm

21. July 25, 2008Abigail Bickley, PAN 200821 Scientific Goals of LHC What is dark matter? –Observations of visible matter accounts for only 4% of the Universe. –The search is open for particles or phenomena responsible for dark matter (23%) and dark energy (73%). – A very popular idea is that dark matter is made of neutral but still undiscovered supersymmetric particles. – The gravitational effect of dark matter may make galaxies spin faster than expected – The gravitational field of dark matter deviates the light of objects behind it.

22. July 25, 2008Abigail Bickley, PAN 200822 Common Misconceptions –Theoretical existence –Created in high energy collisions of particles such as the protons –Public concern is that the energy of the collisions at the LHC will be sufficient to create microscopic black holes Scientific Rebuttal: –Cosmic rays are particles produced in outer space that are accelerated to energies far exceeding those of the LHC. –Cosmic rays travel throughout the Universe, and have been bombarding the Earth’s atmosphere continually since its formation 4.5 billion years ago. –Since the much higher-energy collisions provided by nature for billions of years have not harmed the Earth, there is no reason to think that any phenomenon produced by the LHC will do so. Massive Black Hole Public concern exists about the possibility of black hole creation at LHC Macroscopic Black Holes: –Massive black holes are formed in nature as a result of star collapse –Results in a very large amount of matter being confined to a very small volume Microscopic Black Holes:

23. July 25, 2008Abigail Bickley, PAN 200823 Watching a Collision Microscopic view 0 fm/c~2 fm/c~7 fm/c>7fm/c Time ~6x10 -24 s~21x10 -24 s>21x10 -24 s Remember: E=mc 2 so lots of energy means lots of mass!!!

24. July 25, 2008Abigail Bickley, PAN 200824 Watching a Collision

25. July 25, 2008Abigail Bickley, PAN 200825 The Detectors: CMS Compact Muon Solenoid Cylindrical detector –69ft long –52ft diameter –25,000,000lbs Cost: –$480M Collaboration: –~2600 people –180 institutions –38 countries Scientific Goal: general ‑ purpose detector designed to cover the widest possible range of physics, from the search for the Higgs boson to supersymmetry (SUSY) and extra dimensions

26. July 25, 2008Abigail Bickley, PAN 200826 The Detectors: CMS Compact Muon Solenoid Cylindrical detector –69ft long –52ft diameter –25,000,000lbs Cost: –$480M Collaboration: –~2600 people –180 institutions –38 countries Scientific Goal: general ‑ purpose detector designed to cover the widest possible range of physics, from the search for the Higgs boson to supersymmetry (SUSY) and extra dimensions

27. July 25, 2008Abigail Bickley, PAN 200827 The Detectors: ATLAS No acronym Dimensions –151ft long –82ft diameter –7,000,000lbs Cost: –$520M Collaboration: –1900 people –164 institutions –35 countries Scientific Goal: general ‑ purpose detector designed to cover the widest possible range of physics, from the search for the Higgs boson to supersymmetry (SUSY) and extra dimensions

28. July 25, 2008Abigail Bickley, PAN 200828 The Detectors: ATLAS No acronym Dimensions –151ft long –82ft diameter –7,000,000lbs Cost: –$520M Collaboration: –1900 people –164 institutions –35 countries Scientific Goal: general ‑ purpose detector designed to cover the widest possible range of physics, from the search for the Higgs boson to supersymmetry (SUSY) and extra dimensions

29. July 25, 2008Abigail Bickley, PAN 200829 The Detectors: ALICE A Large Ion Collider Experiment Cylindrical detector –85ft long –52ft diameter –10,000,000lbs Cost: –$110M Collaboration: –1500 people –104 institutions –31 countries Scientific Goal: specialized in analysing lead-ion collisions. It will study the properties of quark-gluon plasma, a state of matter where quarks and gluons, under conditions of very high temperatures and densities, are no longer confined inside hadrons. Such a state of matter probably existed just after the Big Bang, before Particles such as protons and neutrons were formed.

30. July 25, 2008Abigail Bickley, PAN 200830 The Detectors: ALICE A Large Ion Collider Experiment Cylindrical detector –85ft long –52ft diameter –10,000,000lbs Cost: –$110M Collaboration: –1500 people –104 institutions –31 countries Scientific Goal: specialized in analysing lead-ion collisions. It will study the properties of quark-gluon plasma, a state of matter where quarks and gluons, under conditions of very high temperatures and densities, are no longer confined inside hadrons. Such a state of matter probably existed just after the Big Bang, before Particles such as protons and neutrons were formed.

31. July 25, 2008Abigail Bickley, PAN 200831 The Detectors: ALICE A Large Ion Collider Experiment Cylindrical detector –85ft long –52ft diameter –10,000,000lbs Cost: –$110M Collaboration: –1500 people –104 institutions –31 countries Scientific Goal: specialized in analysing lead-ion collisions. It will study the properties of quark-gluon plasma, a state of matter where quarks and gluons, under conditions of very high temperatures and densities, are no longer confined inside hadrons. Such a state of matter probably existed just after the Big Bang, before Particles such as protons and neutrons were formed. ALICE Virtual Tour

32. July 25, 2008Abigail Bickley, PAN 200832 The Detectors: LHCb Scientific Goal: specializes in the study of the slight asymmetry between matter and antimatter present in interactions of B-particles (particles containing the b quark). Understanding it should prove invaluable in answering the question: “Why is our Universe made of the matter we observe?” Large Hadron Collider beauty Dimensions –69ft long –33ft high –43ft wide –5,600,000lbs Cost: –$520M Collaboration: –650 people –47 institutions –14 countries

33. July 25, 2008Abigail Bickley, PAN 200833 The Detectors: LHCb Scientific Goal: specializes in the study of the slight asymmetry between matter and antimatter present in interactions of B-particles (particles containing the b quark). Understanding it should prove invaluable in answering the question: “Why is our Universe made of the matter we observe?” Large Hadron Collider beauty Dimensions –69ft long –33ft high –43ft wide –5,600,000lbs Cost: –$520M Collaboration: –650 people –47 institutions –14 countries

34. July 25, 2008Abigail Bickley, PAN 200834 Data Rates and Volume Raw Rate: –150M sensors record data at 40M/s Filtered Rate: –100 collisions per sec Annual Data: –15PB = 15,000,000GB –100,000 DVDs per year 3miles 9.3miles 18.6miles 12.4miles

35. July 25, 2008Abigail Bickley, PAN 200835 The Grid Data access required for all collaborators Geographically dispersed globally The creation of a "virtual supercomputer" composed of a network of loosely-coupled computers, acting in concert to perform very large tasks.

36. July 25, 2008Abigail Bickley, PAN 200836 http://www.symmetrymagazine.org/breaking/2008/04/14/what-can-we-expect-from-the-lhc/ Countdown…. June 16th, 2008: beam pipe completed August 2008: beam injection into LHC October 2008: beam circulation December: first collisions???!!!

37. July 25, 2008Abigail Bickley, PAN 200837 Stay Tuned….

38. July 25, 2008Abigail Bickley, PAN 200838 Resources LHC Homepage –http://lhc.web.cern.ch/lhc/http://lhc.web.cern.ch/lhc/ LHC Status & Schedule –http://www.lhcountdown.com/http://www.lhcountdown.com/ US LHC –http://www.uslhc.us/LHC_Sciencehttp://www.uslhc.us/LHC_Science LHC Safety –http://public.web.cern.ch/Public/en/LHC/Safety-en.htmlhttp://public.web.cern.ch/Public/en/LHC/Safety-en.html CERN Web –http://public.web.cern.ch/Public/en/LHC/WhyLHC-en.htmlhttp://public.web.cern.ch/Public/en/LHC/WhyLHC-en.html