Tsinghua, Beijing April 2009 Felicitas Pauss

1. The Large Hadron Collider at CERN:Entering a new era in unravelling the mystery of matter, space and time Tsinghua, Beijing April 2009 Felicitas Pauss LHC

2. Big Bang Proton Atom Radius of Earth Earth to Sun Radius of Galaxies Universe LHC Super-Microscope Hubble ALMA cm WMAP VLT Study the structure of the Universe at its most fundamental level:explore the basic physics laws which govern the fundamental building blocks of matter and the structure of spacetime Particle Physics Tsinghua University Beijing, April 2009

3. Particle mass ? Dark Matter ? Unification of Forces ? Matter-Antimatter Asymmetry? LHC Answers to open questions  LHC at CERN Open Fundamental questions Tsinghua University Beijing, April 2009

4. CMS LHCb ALICE LHC ring: 27 km circumference ATLAS Enter a New Era in Fundamental Science Start-up of the Large Hadron Collider (LHC), one of the largest and truly global scientific projects ever, is the most exciting turning point in particle physics. Will address some of the most fundamental questions in modern physics Tsinghua University Beijing, April 2009

5. LHC: Exploration of a new energy frontier Proton-proton collisions at ECM = 14 TeV Heavy Ions: Lead-lead collisions: Energy/nucleon = 2.76 TeV/u • The LHC will illuminate a new landscape of physics, possibly answering some of the most fundamental questions in modern physics, like e.g. • The origin of mass • Unification of fundamental forces • New forms of matter • Extra dimensions of spacetime LHC Tsinghua University Beijing, April 2009

6. Due to LHC Future of High-Energy Frontier CERN became a GLOBAL LABORATORY Overall increase of CERN Users since May 2001: 46% 26% Member States 97% Observer States (India, Israel, Japan, Russia, Turkey, USA) 121% Other States Tsinghua University Beijing, April 2009

7. 3 Institutes Inst. of Atomic Energy, Beijing Hua-Zhong Normal Univ., Wuhan Hua-Zhong Univ., Wuhan 7 members 4 Institutes IHEP Beijing Nanjing Univ. Shangdong Univ. USTC Hefei 31 members 3 Institutes IHEP Beijing Peking Univ. USTC Hefei 55 members 1 Institute Tsinghua University, Beijing 14 members Chinese Involvement in LHC Experiments Chinese Institutes are involved in all 4 LHC experiments LHC Hardware contributions Preparation for physics analysis LCG: Tier-2 at IHEP Tsinghua University Beijing, April 2009

8. 32 MDT constructed at IHEP Muon trigger chambers construction at Shandong Chinese muon chambers installed in the ATLAS detector Chinese Involvement in LHC Experiments ATLAS China Group, meeting IHEP, May 2005 Examples Tsinghua University Beijing, April 2009

9. 1/3 of CSC chamber production at IHEP Support carts All support carts for endcap disks were built at Hudong Shipyards CSC in CMS RPC chambers are mounted behind the CSCs RPC’s for barrel muon system, Peking University Chinese Involvement in LHC Experiments Examples CMS infrastructure and cabling and contribution to purchase of crystals from SIC Tsinghua University Beijing, April 2009

10. Contribution to the production and commissioning of the read-out and trigger electronics for the Photon spectrometer CCNU, Wuhan HUST, Wuhan CIAE, Beijing PHOS Construction of the HV card testing system at Tsinghua     Testing of all the HV cards at NIKHEF (1850 HV boards) Chinese team participated in the ALICE installation at Point 2 at Tsinghua : Construction and testing of Gigabit Ethernet Board (GEB),    Optical Receiver Card (ORC) ORC GEB Chinese Involvement in LHC Experiments Examples Tsinghua University Beijing, April 2009

11. Collisions at LHC …. in 2009 Protons, Ebeam= 7 TeV Protons, Ebeam= 7 TeV Beam crossings : 40 Million / secp p - Collisions : ~ 600 Million / sec Write to disk : ~ 100 / sec, 1-2 Mbyte each Tsinghua University Beijing, April 2009

12. Beam Conditions for Physics • Machine protection will be tested with beam (at 0.45 TeV energy levels) • Beam energy limit in 2010: 5 TeV • Estimated integrated luminosity • The during first 100 days of operation.. ≈100pb-1 Peak L of 5.1031η (overall) = 10% gives 0.5pb-1/day Peak L of 2.1032η (overall) = 10% gives 2.0pb-1/day • During next 100 days of operation ≈ 200pb-1? • Towards end of year (2010)heavy ion run The LHC is an unprecedented adventure Imperative to progress with care Tsinghua University Beijing, April 2009

13. Present Status of Experiments Use time in most efficient way: Installation of some detector components, some repairs, commissioning using cosmics Gain operation experience in situ before collisions start CMS: 300 million cosmic events ATLAS: 216 million cosmic events CMS Tsinghua University Beijing, April 2009

14. g g W/Z W/Z Basic processes at LHC Tsinghua University Beijing, April 2009

15. 30 pb-1 Background for new physics Need to understand very well > 200 pb-1 LHC Physics in 2009/2010 First beams: very early physics - rediscover SM physics Detector synchronization, in-situ alignment and calibration 10 pb-1:Standard Model processes measure jet and lepton rates, observe W, Z bosons first look at possible extraordinary signatures… Measure Standard Model Processes(at 10TeV need ~ 30pb-1): ~ 104 Z  e+e- (golden Z’s for detector studies (1%)) ~ 105 W  e ~ 103 ttbar (measure  to 10%) Initial Higgs searches and searches for physics beyond the SM Entering Higgs discovery era and explore large part of SUSY and new resonances at ~ few TeV Tsinghua University Beijing, April 2009

16. “ We are ready for an unforeseen event that may or may not occur” (A. Gore) LHC discoveries vs. time: we can dream !! Update 2009 L=1035 Tsinghua University Beijing, April 2009

17. CMS LHCb ALICE LHC ring: 27 km circumference ATLAS Very exciting years are ahead of us 谢谢! Tsinghua University Beijing, April 2009