chris parkes 1 lhc the energy frontier chris parkes, gridpp 8, april 2012 atlas cms alice lhcb

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Chris Parkes 1 LHC The Energy Frontier Chris Parkes, GridPP 8, April 2012 ATLAS CMS ALICE LHCb Slide 2 Direct Production Simpler to interpret Probes masses < E Two Routes to New Physics Chris Parkes 2 Indirect Effects Model dependent interpretations Probes very high mass scales virtual new particles E=mc 2 b New particles Slide 3 Contents: Selected new results LHC Status 2011 data and 2012 expectation Heavy Ions (mainly ALICE) Suppression/enhancement of particle rates Direct Production (mainly ATLAS/CMS) The H word Electroweak / Top physics SUSY Indirect effects (mainly LHCb) Rare Decays CP Violation - charm Chris Parkes 3 Sources: Moriond Eweak, LHCC Slide 4 Chris Parkes 4 LHC: The New Improved Energy Frontier Chris Parkes, GridPP 8, April 2012 Slide 5 75 ns50 ns 2011 recap Increase number of bunches Reduce beam size from injectors Squeeze further Increase bunch intensity Initial commissioning Initial commissioning Scrubbing Mike Lamont, LHCC 5 25 ns test Slide 6 LHC Performance LHC shows excellent performance First two years of physics Recorded 40 pb -1 in 2010 at 7 TeV + Pb-Pb Recorded 5 /1 fb -1 in 2011 at 7TeV + Pb-Pb 2012 now restarted at 8 TeV 6 Power of Grid: All collected data reconstructed and many results on full samples Slide 7 Aims for year: ATLAS/CMS need max luminosity many interactions per bunch crossing >15 fb -1 (3x 2011) LHCb need seconds ! small number interactions per bunch > 1.5fb -1 ALICE heavy ions First proton lead collisions 2012 LHC schedule Q1/Q2 First Collisions 7 Slide 8 2012 LHC schedule Q3/Q4 Special runs Proton- lead Mike Lamont, LHCC Followed by long shutdown to move to ~14 TeV 8 Slide 9 Chris Parkes 9 Heavy Metal Frontier Lead Ions Chris Parkes, GridPP 8, April 2012 Slide 10 Hadrons suppressed but photons shine ! Hadrons up to p T 100 GeV/c are suppressed Photons up to E T 80 GeV are not 10 Slide 11 Chris Parkes 11 L H C: The Energy Frontier Direct Production Chris Parkes, GridPP 8, April 2012 Slide 12 Chris Parkes 12 Slide 13 Higgs 101 1) The last undiscovered particle in the Standard Model Higgs Mechanism gives masses to the W & Z Chris Parkes 13 Standard Model Particles Higgs boson, spin=0 Electric charge 0 Slide 14 Higgs 101 1) The last undiscovered particle in the Standard Model Higgs Mechanism gives masses to the W & Z Chris Parkes 14 Higgs boson Mass = ? 2) The mass of the Higgs boson is not predicted The rate of production (cross-section) is predicted if you know the mass Slide 15 Higgs 101 Chris Parkes 15 3) The Higgs boson has lots of possible decay modes It prefers to decay to the heaviest thing available Couples to mass But easier to find if low background rates Best channel changes with Higgs mass BR Slide 16 Standard Model Higgs ? Combination of many decay channels with FULL 2011 data sample 9 1) Black solid line below 1: excluded. Observed number of events less than would have if the Higgs had that mass 16 Slide 17 Standard Model Higgs ? Zoom in on interesting region 2) Black dashed line : expected if no Higgs Black solid > black dashed = hint of a Higgs signal 17 Slide 18 Standard Model Higgs ? Black line ~probability of Higgs at that mass Sensitivity comes from channel ATLAS/CMS compatible New Tevatron result also compatible CMS Expected exclusion 114.5 - 543 GeV CMS Observed exclusion 127.5 - 600 GeV 18 Slide 19 Narrowing in on the Higgs Black line From Indirect Effects: top mass and (new) Tevatron W mass Yellow blocks excluded by direct searches Chris Parkes 19 Indirect Effects: Prediction is from Electroweak results- W mass and top mass Slide 20 Electroweak LHC status 20 Cross-sections of Electroweak processes Slide 21 W and Z Production W/Z cross-section ratio sensitive test of SM at LHC W Charge Asymmetry changes sign in LHCb region: constraints on the low x quark content of the protons at high q 2. ATLAS/CMS 21 Slide 22 Top Quark Chris Parkes 22 Slide 23 Top Quark Chris Parkes 23 Top quark spin correlations measured for 1 st time Slide 24 Top Quark Chris Parkes 24 Top quark mass approaching Tevatron precision Slide 25 25 Supersymmetry (SUSY) 101 Propose new symmetry of nature: Supersymmetry Spin Fermions (quarks, leptons) spin 0 boson superpartner Spin 1 Bosons spin fermion superpartner SUSY not an exact symmetry Mass of SUSY particles Mass of normal particles Since none discovered yet Slide 26 26 SUSY Motivation 4. SUSY provides a theoretical route to include gravity in standard model, and needed in string / M-theory 1/Strength Log Energy GeV 1. SUSY allows unification of the forces2. SUSY cancels divergences in SM SUSY: theoretically beautiful and convenient but is it true ? 3. Lightest SUSY particle (LSP) is candidate for dark matter Most models LSP is stable neutralino Slide 27 SUSY + Exotics Searches Summary F. Cerutti - LNF-INFN 27 Optimal use of delivered data: Enlarge range of experimental topologies look at as many experimental topologies as possible Then make happy our friend theorists: translate results in constraints to large variety of models ATLAS many analyses with FULL 2011 Luminosity Slide 28 SUSY + Exotics Searches Summary F. Cerutti - LNF-INFN 28 Optimal use of delivered data: Enlarge range of experimental topologies look at as many experimental topologies as possible Then make happy our friend theorists: translate results in constraints to large variety of models Good Fraction of analyses updated with FULL 2011 Luminosity SUSY is alive but she has a headache Slide 29 Chris Parkes 29 Interaction Point Muon System Calorimeters Tracking System Vertex Locator RICH Detectors Beyond The Energy Frontier Indirect Effects Chris Parkes, GridPP 8, April 2012 Slide 30 Very rare decay enhanced rate by new physics LHCb rate < 4.5 x 10 9 (95%CL), CMS rate < 7.7 x 10 9 (95%CL), ATLAS < 22 x 10 9 (95%CL) New physics SUSY models with large tan ~ ruled out Chris Parkes 30 green allowed regions black/red exclusion limits from CMS yellow - exclusion region from LHCb B s result SM prediction 3.2 x 10 9 Rare Decays: B s + - N. Mahmoudi Slide 31 Most rare decay ever seen ! B + + + First observation 256 events 5.2 significance Chris Parkes 31 B 0 K *0 + - Constraining new physics up to 10TeV Beyond the Energy Frontier Slide 32 32 C P CPCP Parity Inversion Spatial mirror Charge Inversion Particle-antiparticle mirror Matter anti-matter (CP violation) 101 Slide 33 CP Violation Discoveries Strange Quark System (Kaons) Discovery of CP Violation Beauty Quark systems (B) CP violation theory in CKM matrix Also B s, see next slide Charm System (D) Is there CP Violation in Charm quarks ? Predicted to be very small in SM Good way of searching for New Physics ? Chris Parkes 33 Slide 34 6 Asymmetry B s Matter Antimatter Asymmetry Chris Parkes 34 ArXiv:1202.6251v1, Feb 2012 B B BsBs BsBs 3.3 Asymmetry FIRST CP Slide 35 CP Violation in B s J/ Powerful analysis to look for New Physics Had been hints from TeVatron but more precise LHC results give SM value Chris Parkes 35 1 fb -1, LHCb-CONF-2012-002 Slide 36 LHCb LHCc LHCb was designed for b-quark studies But also ideal for studies of slightly shorter lived c quark, and 20 times more events CP Violation in charm sector (was) predicted to be very small in Standard Model < 0.1 % Bigger than this New Physics ! Chris Parkes 36 c c e.g. Slide 37 CP Violation: Problem 1 Initial Condition Technical Scale Drawing of LHC Collision Chris Parkes 37 Proton (Matter) Start with matter and no antimatter Ending with more matter than antimatter is not a surprise Take difference in CP Violation between two decays Slide 38 CP Violation: Problem 2 Detector Chris Parkes 38 So if matter goes to a +ve particle and antimatter to ve Go to different parts of detector can fake CP violation 1)Take difference in CP Violation between two decays 2)Reverse Magnetic Field Periodically 3)Choose a symmetric decay +ve charge -ve charge Particles bend in magnetic Field Slide 39 Direct CP Violation in Charm Chris Parkes 39 What we measure What we want What we dont want (1) What we dont want (2) Slide 40 Chris Parkes 40 What we measure What we want What we dont want (1) What we dont want (2) Symmetric Final State Direct CP Violation in Charm Slide 41 Chris Parkes 41 What we measure What we want What we dont want (1) What we dont want (2) Symmetric Final State Magnetic Field Direct CP Violation in Charm Slide 42 Chris Parkes 42 What we measure What we want What we dont want (1) What we dont want (2) Symmetric Final State Magnetic Field Take Difference of final states Direct CP Violation in Charm Slide 43 High Statistics 1.4M K + K -, 0.4M + - Chris Parkes 43 Phys. Rev. Lett. 108, 111602 (2012), 12 th March 2012 Slide 44 Direct CP Violation in Charm Chris Parkes 44 New Prelim Result, 28 th February Confirmation of Effect World Average 3.7 Slide 45 Chris Parkes 45 First evidence of CP violation in charm sector Interpretation: M. Gersabeck, S. Borghi, CP http://arxiv.org/abs/1111.6515 Direct CP Violation in Charm Average: Marco Gersabeck Slide 46 New Physics ? CP Violation in charm sector (was) predicted to be very small in Standard Model < 0.1 % We measure 0.820.24% (on difference) New Physics ? Well maybe not Chris Parkes 46 Slide 47 Pb Pb collisions Particle suppression / enhancement in new state of matter Higgs: Tantalising hints of SM Higgs around 125 GeV We will know this year SUSY: No signs of her yet in direct production or rare decays Rare Decays: Most rare decay ever seen CP Violation: First evidence for CP violation in charm sector Compatible with SM ? 2011 Summary Chris Parkes 47 Slide 48 Pb Pb collisions Particle suppression / enhancement in new state of matter Higgs: Tantalising hints of SM Higgs around 125 GeV We will know this year SUSY: No signs of her yet in direct production or rare decays Rare Decays: Most rare decay ever seen CP Violation: First evidence for CP violation in charm sector Compatib