1. What happens at CERN? Roger Barlow Manchester University

2. The smaller the detail The bigger the apparatus Letters ~1/5 mm Details of print ~1/50 mm Individual paper fibres ~1/500 mm

3. The World’s biggest Microscope

6. CERN A co- operative European effort – sharing costs between many countries

7. Digging out a cavern

8. The final pillar

9. Tunnel – completed

10. LHC A machine for colliding protons at very high energies v=0.99999998 c

11. What happens? Protons collide with other protons Energies high enough to make new particles Particles stream out of the collision and analysed by detectors Results are recorded electronically and stored on disk for later analysis

12. The ATLAS detector

13. ATLAS in reality

14. Part of another detector (OPAL)

15. The DELPHI detector

16. What we see Proton hits proton and makes lots of stuff

18. Towards the New Periodic Table(?)

19. So finally Particle Physics is still a live subject. New discoveries are made. Textbooks go out of date. We understand things better. CERN is where it’s happening. For Europe and the world CERN is important for physicists and for taxpayers Visiting CERN is a great experience.