1. 1 LHC and CMS Status Robert M. Harris Fermilab Fermilab All Experimenters Meeting Nov. 10, 2008

2. Robert Harris, Fermilab2 Outline l LHC Status l CMS Commissioning Status l LPC Topic: Jet Corrections and Jet Physics l Conclusions

3. Robert Harris, Fermilab3 LHC Incident l Some details è Splice warmed above critical T, connection melted, and an arc formed. è Vacuum vessel ruptured, helium vaporized & escaped with large force. è Magnets moved, sometimes breaking loose from concrete anchors. è “The number of magnets to be repaired is at most 5 quadrupoles and 24 dipoles.” is a quote from the report. l Operation of the LHC was shutdown on Sep. 19 è On Oct. 16 CERN released an analysis of the incident (hyperlink). analysis of the incident (hyperlink) è “A faulty electrical connection between two magnets was the cause.”

4. Robert Harris, Fermilab4 LHC Status l Course of action è Spares exist and most magnets can be repaired outside the tunnel. è Investigating vacuum pipe contamination level and remediation plan. è Investigating improving detection and protection (pressure relief system). è Detailed scope and schedule still being determined. l When should we expect the LHC to re-start ? è “Early spring 2009” according to press release on Sep 23. è “around May 2009” according to Jos Engelen at CMS week on Sep 26. è “the LHC is able to restart in 2009” according to press release on Oct 16. è “not before May 2009” according to director designate Rolf Heuer on Oct 28. l At what collision energy ? è Eric Prebys says it is extremely likely that entire 2009 run will be at 10 TeV. è Rolf Heuer has implied the LHC will be cautious about raising the energy. à Emphasis on avoiding further incidents rather than going for highest energy quickly.

5. Robert Harris, Fermilab5 CMS Installation Status l CMS is closed up and ready for beam è Currently taking cosmic rays. l Nearly all detector systems are in place è Including both Ecal Endcaps à Which made it just in time for 2008 first circulating beams ! è Only missing endcap pre-shower detector. à Plan is to have it ready for installation in February 2009.

6. Robert Harris, Fermilab6 CMS Beam Splash Events l Beam steered into collimators during Sept 10-19 running. l Produced spectacular and useful beam splash events è Demonstrates the vast majority of channels in HCAL are working. è Calibrates the arrival time of energy.

7. Robert Harris, Fermilab7 CMS Cosmic Ray Runs 7 l Cosmic Run At Four Tesla (CRAFT) è Attained goal of 300M events è Established continuous stable running periods over 24 hr duration. è ROC at Fermilab actively contributed to CRAFT shift operations. è CRAFT runs from Oct. 13 – Nov. 11 à Various test runs Nov. 11 - 24 à Then maintenance period begins. Nov. 7

8. Robert Harris, Fermilab8 Jet Energy Corrections l CMS has publicly released its plan for jet energy corrections è Physics Analysis Summary JME-007-002 (Hyperlink)JME-007-002 (Hyperlink) l Data-driven methods to measure jet energy corrections in-situ at CMS. è Techniques inherited from CDF & D0.   +Jet p T balance to measure p T dependence. à Z+jet and top quark as well.  Dijet p T balance for  dependence. è Factorization into sub-corrections. K. Kousouris Reconstructed Jets Calibrated Jets Offset Rel:  Abs: p T EMFFlavorUE Parton Required Corrections Optional Corrections  + jet p T Balance Dijet p T Balance Barrel End Cap End Cap Jet Response

9. Robert Harris, Fermilab9 Jet Physics l We have published CMS plans for jet physics è J. Phys. G: Nucl. Part. Phys. 36 (2009) 015004. (Hyperlink) J. Phys. G: Nucl. Part. Phys. 36 (2009) 015004. (Hyperlink) è Planned measurements of jet p T, dijet mass, and dijet ratio.  Planned searches for dijet resonances and quark compositeness (  ). è With 10 pb -1 of data CMS will probe beyond Tevatron sensitivities. 10 pb -1  + = 3 TeV Jet p T and Contact Interactions 100 pb -1  + = 5 TeV Dijet Ratio and New Physics q* QCD w/wo Jet Corrections QCD

10. Robert Harris, Fermilab10 Conclusions l CMS is preparing for LHC startup in 2009 è At a likely collision energy of √s ≈ 10 TeV l CMS is installed and being commissioned with cosmic rays. l The LPC is leading in jets at CMS è Plans for Jet Energy Corrections at CMS è Plans for Jet measurements and new physics with jets.