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Highlights from the Race to New Physics at the LHC

Highlights from the Race to New Physics at the LHC. Scott Thomas Rutgers University. April 6, 2012. Search for New Physics: Higgs + SUSY + …. LHC has Opened up a Vast Landscape of Un-Explored Territory Many Opportunities to Explore this N ew Territory

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Highlights from the Race to New Physics at the LHC

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  1. Highlights from the Race to New Physics at the LHC Scott Thomas Rutgers University April 6, 2012

  2. Search for New Physics: Higgs + SUSY + … LHC has Opened up a Vast Landscape of Un-Explored Territory Many Opportunities to Explore this New Territory Not Static - Discovery Potential Continually Evolving Strategy: Wide Spectrum of Searches – Mow down Un-Cut Territory Adapt Searches to Exploit Rapidly Changing Discovery Potential ( Search First for What can be Discovered First – Match the Search to the Discovery Potential )

  3. Outline: Simplified Model Topologies CMS Highlights New Physics Searches Di-Jet Regge Resonances, Multi-Jets, Di-Photon + MET, OS Di-lepton, Multi-Lepton, Multi-Lepton + Kinematics Higgs -> Multi-Leptons (Higgs -> Di-Photon, Higgs -> WW -> l n l n ) Consistent On-Shell Effective Theory Coming Highlights for 2012

  4. Search for New Physics: Theory <-> Experiment Underlying Theoretical Framework Models Signatures Simulations Experimental Signature Search Generally No Single Definitive Prediction (SUSY) Just Hope that Some States (Super-Partners ) are Kinematically Accessible Make (Prioritized) List of Signatures and Do the Experimental Searches … SUSY Experimental Searches Decoupling Limits

  5. Organize Mapping Theory <-> Experiment Experiment - Signatures Most Important Metric Production and Decay Topologies -> Final States -> Signatures Relatively Narrow Intermediate States Parameterized by Mass Spectrum, Spins + Quantum Numbers (or Decay Distributions) (More later … ) G / m << 1

  6. Factorized Mapping - Simplified Topologies (Dube, Glatzer, Somalwar, Sood, ST) # Topologies # Decays in Each Topology Acceptance for Topology t in Final State f Final State

  7. Factorized Mapping - Simplified Topologies (Dube, Glatzer, Somalwar, Sood, ST) # Topologies # Decays in Each Topology Acceptance for Topology t in Final State f Final State • Production s’s Factor Out of Problem • Cascade Br’s Factor Out of Problem • Acceptances Factor Out of Problem At = At(mi) Only • Multiple Topologies + Multiple Channels Easily Combined • Good for Arbitrary Relations Among st,Brat,mit (No Assumptions) • Can Add More Topologies Later (Incoherent) • (Since Don’t Simulate Combinations of Topologies) • Report s.Br and s.Br.A(mi) or A(mi) for Each Topology

  8. Factorized Mapping - Simplified Topologies (Dube, Glatzer, Somalwar, Sood, ST) Simulation Production and Decay Topologies Experimental Signature Search • Production s’s Factor Out of Problem • Cascade Br’s Factor Out of Problem • Acceptances Factor Out of Problem At = At(mi) Only • Multiple Topologies + Multiple Channels Easily Combined • Good for Arbitrary Relations Among st,Brat,mit (No Assumptions) • Can Add More Topologies Later (Incoherent) • (Since Don’t Simulate Combinations of Topologies) • Report s.Br and s.Br.A(mi) or A(mi) for Each Topology CDF Tri-Lepton Search Parameterization Becoming Standard for CMS + ATLAS Searches - Benchmarks VeryUseful for Theory-Level Studies… (More later)

  9. Search for New Physics: Experiment Reconstructed Physics Objects jet photon Searching for Extremely Rare Processes (Approaching part per 1015 level ) Control of “Fake” Objects Crucial !! (An example later) electron Object b-jet tau muon

  10. Search for New Physics: Experiment Signature Space - Physics Objects s (fb) 7 TeV W 100,000,000 Z 30,000,000 tt 150,000 WW 40,000 WZ 17,000 ZZ 6,500 H inclusive 17,900 ttW 150 ttZ 100 WWW 60 ttWW 2 ww (400 GeV ) 10 gg (1 TeV) 10 MET , … Jets , b-jets Leptons , taus , Photons , … Searches are Built Around SM (+fake) Backgrounds – Design Searches Away from “Origin” of Signature Space Along Some Axis or Axes

  11. Search for New Physics: Experiment Signature Space - Physics Objects s (fb) 7 TeV W 100,000,000 Z 30,000,000 tt 150,000 WW 40,000 WZ 17,000 ZZ 6,500 H inclusive 17,900 ttW 150 ttZ 100 WWW 60 ttWW 2 ww (400 GeV ) 10 gg (1 TeV) 10 MET , … Jets , b-jets Leptons , taus , Photons , … Searches are Built Around SM (+fake) Backgrounds – Design Searches Away from “Origin” of Signature Space Along Some Axis or Axes

  12. Search for New Physics Highlights: CMS – Rutgers Di-Jet Regge Resonances Multi-Jet Resonances Di-Photon + MET Multi-Lepton Multi-Lepton + Kinematics Higgs -> Di-photon Multi-Jets (CDF) Di-Jet Extinction Boosted top-top-jet … Highlights: CMS Higgs -> WW -> l n l n OS Di-Lepton … Phenomenology: COSET Higgs -> Multi-Leptons Higgs -> WW -> l n l n Kinematic Reconstruction Testing Higgs Mechanism New Physics with Higgs …

  13. Search for New Physics Highlights: CMS – Rutgers Di-Jet Regge Resonances Multi-Jet Resonances Di-Photon + MET Multi-Lepton Multi-Lepton + Kinematics Higgs -> Di-photon Multi-Jets (CDF) Di-Jet Extinction Boosted top-top-jet … Spare Experimental Realities: Triggers, Cuts, Data Analysis, Characterize Backgrounds, Fake Rates, Data Driven Closure Tests, … Highlights: CMS Higgs -> WW -> l n l n OS Di-Lepton … Phenomenology: COSET Higgs -> Multi-Leptons Higgs -> WW -> l n l n Kinematic Reconstruction Testing Higgs Mechanism New Physics with Higgs …

  14. Open String Di-Jet Regge Resonances High pT: (pp jj) Largest – First Place to Look for New Physics String Scale 0 -1 = ms2 Could be O(TeV) SU(2) Gluon Quarks, Gluons = Open String Modes on D-Branes Quark SU(3) W-Boson Open String Regge Excitations - AnyD-Brane Realization String Theory - Observable for ms = O(TeV) - Significant Modification of QCD Tower of Excitations for Gluon, All Quarks, … g* , q* mn2 = n ms2 n = 1,2,3,… Equally Space in m2 Degenerate (up to small finite corrections) Regge Excitation Spins J = 0,…,n Previous Work: Cullen, Perlestein, Peskine+e- Collider Anchordoqui, Goldberg, Lust Di-Jets Interesting Signature Nawata, Stieberger, Taylor (Only some channels, Color Averaged Only, Estimate of Incoherent Widths, No Interference Effects, ... )

  15. Open String Di-Jet Regge Resonances (Kilic, ST) String-String Scattering = n orn n n Veneziano Form Factor ReggeLevel Spin Crossing Symmetry: x <-> y s-Channel Resonances in Many Color and Flavor Channels ms= O(TeV) -Significant Modification of Di-Jets

  16. Open String Di-Jet Regge Resonances (Kilic, ST) QCD 2 -> 2 Scattering Amplitudes with Veneziano Form Factor All Spin and Most Color Channels …

  17. Open String Di-Jet Regge Resonances (Kilic, ST) Singular on s-channel Regge poles - Improve Scattering Amplitudes for Leading Re-scattering Effects - Finite Width of Resonances Modified Optical Theorem: 2 Res2 2 = = Res1 Includes Effects of Coherence Quantum Interference Among Regge Resonances of Different Spin and Intereference with Continuum

  18. Open String Di-Jet Regge Resonances (Kilic, ST) Incorporate Improved Veneziano Amplitudes into Veneziano Monte Carlo (VMC) (Reduces to Pythia 2->2 Scattering for ms -> large) 1st Resonance BIG – Many Quark and Gluon Color and Flavor Channels, Multiple Spins – Add (In)Coherently mn2 Spacing n Grow Rapidly with n 7 Tev Parton Level Constructive Interference Destructive Interference Direct Probe of String Theory

  19. Open String Di-Jet Regge Resonances (Kilic, ST, Harris, …, CMS) ms > 2.4 TeV(3 pb-1) (Eventually - Contact Interaction)

  20. Open String Di-Jet Regge Resonances (Kilic, ST, Harris, …, CMS) ms > 4.0 TeV(1 fb-1) (Eventually - Contact Interaction)

  21. SUSY Topologies Produce Super-Partners in Pairs or Possibly Resonantly if R-Sym Violation SM Particles Emitted in Cascade Decays of Super-Partners R-Symmetry ConservedViolated Lightest StableUn-Stable Super-Partner Jets Jets Lepton Detect Passage Through Detector Generic Non-Degenerate Spectrum - High pT Isolated Objects: Jets, b-Jets, Electrons, Muons, Taus, Z-Bosons, Photons, MET, Top Quarks + Lightest Super-Partner(s) SUSY Great Signature Generator

  22. The Scale of Super-Symmetry Breaking Possible Decay to Goldstino (component of gravitino) Provides a Natural Classification of Inclusive Signatures • Prompt Decay < O(100) TeV • Decay Within Detector O(100) TeV • Effectively Stable in > O(100) TeV • Detector Lightest SM Super-Partner SM Particle Meta-Stable Goldstino Finite Gap  Emitted SM Particle - High pT Blunt Inclusive Analyses that Capture Final Decays to Goldstino are Robust … (No Softening from Compressed Spectrum)

  23. SUSY Inclusive Signature Classification (RPC) Run II Workshop: hep-ph/0008070

  24. SUSY Inclusive Signature Classification (RPC) Run II Workshop: hep-ph/0008070

  25. LHC SUSY Production Irreducible Super-Partner Pair Production Rapidly Beyond Tevatron in Relatively Low Background Final States Strong Production > O(pb-1) (2010 – 2011 ½ -> ) Weak Production > O(fb-1) (2011 ½ – 2012 -> )

  26. Di-Photon + Jets + MET Signature (Gershtein, ST, Zhao, Park, … , CMS) Neutralino -> Photon + Goldstino(Prompt) with Strong Production Necessarily Extra Jet(s) - Reduces Background - … Gluino, Squarks Jets Bino Photon Goldstino

  27. Di-Photon + Jets + MET Signature (Gershtein, ST, Zhao, Park, … , CMS) Neutralino -> Photon + Goldstino(Prompt) with Strong Production Necessarily Extra Jet(s) - Reduces Background - … Significant SM Background Near Origin of Di-photon + MET Space Gluino, Squarks Jets Bino Photon Goldstino

  28. Di-Photon + Jets + MET Signature (Gershtein, ST, Zhao, Park, … , CMS) Neutralino -> Photon + Goldstino(prompt) with Strong Production Necessarily Extra Jet(s) - Reduces Background - … Gluino, Squarks Jets Bino Photon Goldstino

  29. Opposite Sign Di-Leptons + Jets + MET Signature Neutralino -> Neutralino + Di-Lepton with Strong Production Top-Top Irreducible Background Significant ! (t -> Wb -> l n b) Gluino Jets Squarks Jets Wino Lepton Slepton Lepton Bino

  30. Opposite Sign Di-Leptons + Jets + MET Signature Top-Top Irreducible Background Significant ! (t -> Wb -> l n b) (Park, Lath, ST) Blue MET Green Vector Sum ll Average MET Distribution = Average pT(ll) Distribution In-Situ Data Driven MET Characterization Dominant Background is Self-Calibrating ! MET or pT(ll) (GeV)

  31. Opposite Sign Di-Leptons + Jets + MET Signature Neutralino -> Neutralino + Di-Lepton with Strong Production Top-Top Irreducible Background Significant ! (t -> Wb -> l n b) (CMS) Gluino Jets Squarks Jets Wino Lepton Slepton Lepton Bino HT = S |pT| Jets

  32. Tri-Leptons + MET Signature Relatively Low Backgrounds (WZ + Di-Leptons + fakes) Chargino -> Neutralino + Lepton Neutralino -> Neutralino + Di-Lepton Wino Tevatron – Narrowly Focussed on Classic Tri-Lepton Signature (Flavor + Charge + MET) LHC – Considerably Expanded Scope + Intrinsic Sensitivity … Lepton Slepton Lepton Bino

  33. Multi-Lepton Signatures (Somalwar, Gray, Zhao, Park, ST) Backgrounds Closely Correlate with Type of Di-Lepton Pairs within Set of Multi-leptons

  34. Multi-Lepton Signatures (Somalwar, Gray, Zhao, Park, ST) Classify All Multi-Leptons Channels: Defines a Multi-Channel Hierarchy of Backgrounds

  35. Multi-Lepton Signatures (Somalwar, Gray, Zhao, Park, ST) Classify All Multi-Leptons Channels: Defines a Multi-Channel Hierarchy of Backgrounds

  36. Multi-Lepton Signatures (Somalwar, Gray, Zhao, Park, ST) Classify All Multi-Leptons Channels: Defines a Multi-Channel Hierarchy of Backgrounds

  37. Multi-Lepton Signatures (Somalwar, Gray, Zhao, Park, ST) Classify All Multi-Leptons Channels: Defines a Multi-Channel Hierarchy of Backgrounds Use Classification Along with NDY > 0 On/Off Z to Make Hierarchical Ordering of Multi-Lepton Channels According to Background Events -> Channels Lowest to Highest Background Exclusively Maximizes Sensitivity (Given Signal may Overlap with Low Background Channels) Exclusive Combination of All Channels (CMS)

  38. Multi-Lepton Signatures (Somalwar, Gray, Lath, ST, Walker, Arora, Panwalker, Contreras-Campana, … CMS) 157 Exclusive Channels -> ST Analysis 4.7 fb-1 ST = S |pT| All Objects

  39. Multi-Lepton Signatures (Somalwar, Gray, Lath, ST, Walker, Arora, Panwalker, Contreras-Campana, … CMS) 157 Exclusive Channels -> MET + HT Analysis 4.7 fb-1

  40. Multi-Lepton Signatures (Somalwar, Gray, Lath, ST, Walker, Arora, Panwalker, Contreras-Campana, … CMS) Slepton Co-NLSP - Prompt Decay to Goldstino with Strong Production Gluino Jets Squarks Jets Wino Bino Lepton SleptonR Lepton Goldstino Leptonic RPV and No-MET Hadronic RPV Topologies also … mq = 0.8 mg , mlR= 0.3 mC, mN = 0.5 mC

  41. The Variables Object pT’ , MET, HT, ST, meff, … Very Blunt Instruments Useful Far Out Along Axes in the Signature Space where SM Backgrounds are Low Low “Temperature” Regions of Signature + Phase Space Searches are Effectively Thermal in these Low “Temperature” Regions Kinematic Correlations are Required for More Refined Measurements Closer to the Origin of Signature Space (Less Inclusive) Signal Might be Buried There Under SM Background Low ST, MET, … , Top, Bottom, or Tau Enriched MET , … Jets , b-jets Leptons , taus , Photons , …

  42. jet jet jet jet jet jet Multi-Jet Signature (Lath, Halkiadakis, Essig, ST) High pT: (pp Multi-jets) Large Purely Hadronic Final States Very Difficult – Prodigious QCD Background … Axis Un-explored Great Discovery Potential to Strong New Physics QCD Fills Up Phase Space Standard Techniques Fail

  43. Multi-Jet Signature (Lath, Halkiadakis, Essig, ST) Boosted Tri-Jet Resonance Focus on Resolved Individual Jets Rather Than Giant Merged Jets QCD Fills Up Phase Space Approximately Scale Invariant Combinatoric Confusion Cut mjet-jet-jet Accept SUSY – Hadronic RPV Boosted Resonance pp QQ j j j pT,jet-jet-jet j j j

  44. Multi-Jet Signature (Lath, Halkiadakis, Seitz, Dugan, Hidas, ST, … , CMS) Boosted Tri-Jet Resonance Focus on Resolved Individual Jets Rather Than Giant Merged Jets SUSY – Hadronic RPV pp QQ j j j j j j

  45. Multi-Jet Signature (Lath, Halkiadakis, Seitz, Dugan, Hidas, ST, … , CMS) Boosted Tri-Jet Resonance Focus on Resolved Individual Jets Rather Than Giant Merged Jets SUSY – Hadronic RPV pp QQ j j j j j j

  46. Multi-Jet Signature (Lath, Halkiadakis, Seitz, Dugan, Hidas, ST, … , CMS) Boosted Tri-Jet Resonance Focus on Resolved Individual Jets Rather Than Giant Merged Jets CDF Search First Observation of Boosted Tops pt>300 GeV (Tri-Jet Resonance) Excess ! 5 fb-1 Results Soon Extended Other Searches tt+jet Leptons …

  47. Cascade Decay Correlations S-matrix = f( mijk…2 ) (Unpolarized, T- Invariant Spins Unobserved) f( mijk…2 ) = f( mij2) Probability Distribution in Generalized Dalitz Space mij2 i,j = All Pairs True of Sub-processes Also Exploit (Sub-Process) Correlations in Searches

  48. Cascade Decay Correlations 3-Point Interaction f(p12,p22,p32) Amplitude (Almost) Uniquely Determined by Lorentz Invariance up to Momentum Dependent Form Factor J = ½, ½, 0 J = ½, ½, 1 …… Near Mass Shell Form Factor Nearly Constant /m <<1

  49. Consistent On-Shell Effective Theory for Cascade Decay Correlations (COSET) (Graesser, ST Shelton, Park) • Develop Effective Field Theory - • Calculate Cascade Decay Correlations • Systematic Expansion in /m , m/M • Provides Framework to Consider Wide Range Standard Model + New Physics Processes Correlations in Generalized Multi-Dimensional DalitzSpaces of Invariants Leading Order in COSET Expansion: Sequential Two Body Cascade Decays Invariant Mass Distributions in Generalized Dalitz Space Spin 0, ½ (SUSY) NoArbitrary Couplings

  50. COSET – Sequential Two-Body Cascade Decay Correlations (Graesser, ST Shelton, Park) ½ 0 0 0 Chiral Insertion ½ ½ ½ 0 ½ ½ ½ 0 ½ Triangle Half-Cusp Hump (1 / )( d  / dx) (1 / )( d  / dx) (1 / )( d  / dx) x = mll / mllmax x x x Chiral Structure Unique- Independent of Majorana/Weyl, Dirac, PseudoDirac, … Only Possibilities for Adjacent Branch Correlations with J=0, ½ (Almost) Complete List of Correlations - Three Sequential Decays J <= 1

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