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Physics at 7 TeV With Less Than 1 fb -1

Physics at 7 TeV With Less Than 1 fb -1. Scott Thomas Rutgers University US CMS Meeting May 7, 2010. Focus Rutgers: Early – Medium Term Physics. Open String Di-Jet Regge Resonances Benchmarks / Parameter Spaces

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Physics at 7 TeV With Less Than 1 fb -1

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  1. Physics at 7 TeVWith Less Than 1 fb-1 Scott Thomas Rutgers University US CMS Meeting May 7, 2010

  2. Focus Rutgers:Early – Medium Term Physics • Open String Di-Jet Regge Resonances • Benchmarks / Parameter Spaces • Multi-Leptons, Photons, Higgs, Z’s, HITs from . Split Messenger GMSB • Model Independent Combination of Multiple Channels • Consistent On-Shell Effective Theory for . Cascade Decay Correlations • Top Quark . Mass, Spin, New Physics in Decay Correlations . MET Background . Kinematic Fits, … • SUSY Di-Object Correlations • NNOMET Procedure for Extracting Masses and Spins • Multi-Jet Resonances 2

  3. (Lath, Rose, Kilic, Winter, Halkiadakis, Thomas) 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 - Any Realization of . String Theory - Observable for ms = O(TeV) Tower of Excitations for Gluon, All Quarks, … g* , q* mn2 = n ms2 n=0,1,2,3,… Equally Spaced in m2 Degenerate (up to small finite corrections) Regge Excitation Spins J = 0,1,…,n 3

  4. (Lath, Rose, Kilic, Winter, Halkiadakis, Thomas) Open String Di-Jet Regge Resonances String-String Scattering = n + n n n Veneziano Form Factor Regge Level Spin Crossing Symmetry: x $ y s-Channel Resonances for Entire |Matrix Element|2 ms = O(TeV) -Significant Modification of Di-Jets 4

  5. (Lath, Rose, Kilic, Winter, Halkiadakis, Thomas) Open String Di-Jet Regge Resonances Di-Jets • s » ms2 Regge Resonances mn2 = n ms2 , n = n(ms) • 2. s ¿ ms2 Contact Interaction Form Factor Previous Work Cullen, Perlestein, Peskine+e- Colliders Anchordoqui, Goldberg, Lust,Tried To Interpret Open String Amplitudes. Nawata, Stieberger, Taylor Only Some Channels . No Quantum Interference . Widths – Incoherent Limit Bad Veneziano Monte Carlo Generator (Can Kilic) 5

  6. (Lath, Rose, Kilic, Winter, Halkiadakis, Thomas) Open String Di-Jet Regge Resonances 1st Resonance BIG – . All Channels, . Gluon, All Quarks, . Multiple Spins mn2 Spacing n Grow Rapidly with n Constructive-Destructive . Opposite Standardg*, q* 7 Tev Parton Level Constructive Interference Destructive Interference Model Independent Probe of String Theory . (Minimal Regge Resonances – Actual Model Likely Stronger) Incorporate String Regge Resonances into Model List for . Di-Jet Resonance Search (Contacted Rob Harris) Contact Interaction Search Most Sensitive (Probe ms2 > s) 6

  7. Benchmarks / Parameter Spaces • Cautionary Tale of Two Collaborations: • Over Many Decades Theorists Developed a Framework for New Astro Physics • A Standard Benchmark for the New Astro Physics Emerged • When Experimental Advances Finally Probed the New Astro Physics • Collaboration A – • Developed Search Strategy Based on the Benchmark - . Analyzed an Enormous Amount of Data with no Success • Collaboration C – • Ignored the Benchmark - First Searched Quickly through . Data for Signatures that Could be Discovered First • Discovered New Astro Physics !! . (Immediately Confirmed by Collaboration A in Existing Data) 7

  8. Benchmarks / Parameter Spaces • Cautionary Tale of Two Collaborations: • Over Many Decades Theorists Developed a Framework for New Astro Physics • A Standard Benchmark for the New Astro Physics Emerged • When Experimental Advances Finally Probed the New Astro Physics • Collaboration A – • Developed Search Strategy Based on the Benchmark - . Analyzed an Enormous Amount of Data with no Success • Collaboration C – • Ignored the Benchmark - First Searched Quickly through . Data for Signatures that Could be Discovered First • Discovered New Astro Physics !! . (Immediately Confirmed by Collaboration A in Existing Data) • This Already Happened in the Search for Extrasolar Planets ! • Benchmark = Jupiter mass Planet with O(10) yr Orbit • Discovery = Jupiter mass Planet with O(few) day Orbit 8

  9. Benchmarks / Parameter Spaces • Cautionary Tale of Two Collaborations: • Over Many Decades Theorists Developed a Framework for New Astro Physics • A Standard Benchmark for the New Astro Physics Emerged • When Experimental Advances Finally Probed the New Astro Physics • Collaboration A – • Developed Search Strategy Based on the Benchmark - . Analyzed an Enormous Amount of Data with no Success • Collaboration C – • Ignored the Benchmark - First Searched Quickly through . Data for Signatures that Could be Discovered First • Discovered New Astro Physics !! . (Immediately Confirmed by Collaboration A in Existing Data) Lesson • This Already Happened in the Search for Extrasolar Planets ! • Benchmark = Jupiter mass Planet with O(10) yr Orbit • Discovery = Jupiter mass Planet with O(few) day Orbit 9

  10. Benchmarks / Parameter Spaces • Cautionary Tale of Two Collaborations: • Over Many Decades Theorists Developed a Framework for New SUSY Physics • A Standard Benchmark for the New SUSY Physics Emerged • When Experimental Advances Finally Probed the New SUSY Physics • Collaboration A – • Developed Search Strategy Based on the Benchmark - . Analyzed an Enormous Amount of Data with no Success • Collaboration C – • Ignored the Benchmark - First Searched Quickly through . Data for Signatures that Could be Discovered First • Discovered New SUSY Physics !! . (Immediately Confirmed by Collaboration A in Existing Data) • This Could Happen in the Search for New Physics at the LHC • Benchmark = … , mSUGRA , … (See Backup Slides for Comments) • Discovery = … , SUSY with Compressed Spectrum , … , ??? 10

  11. (Gershtein, Shih, Thomas) SUSY Benchmarks / Parameter Spaces • Search First for What Can be Discovered First Y. Gershtein Gauge Ordered Spectrum . “Natural Expectation” Compressed Spectrum “Reasonable Expectation” 11

  12. (Gershtein, Shih, Thomas) SUSY Benchmarks / Parameter Spaces • Discovery Potential of Gauge Ordered vs Compressed Spectra Minimal Gauge Mediation: Gauge Ordered Spectrum Weak Production Dominates Reach not Far Beyond Tevatron N5=1 (Widely Held View – Even Among Theorists who Should Know Better) Y. Gershtein General Gauge Mediation: Compressed Spectrum Strong Production Dominates Reach Rapidly Exceeds Tevatron 12

  13. (R. Gray, Somalwar, Park, Zhao, Thomas) Gauge Mediation with Split Messengers L, d Independent SUSY Breaking for Minimal Messengers mwino(GeV) Gauge Ordered . Spectra 400 500 mSleptonR(GeV) 60 140 Minimal Gauge Mediation 1200 50 Benchmark Points, . Lines/Slopes, . Manifolds 40 d (TeV) mgluino(GeV) 120 800 30 20 Compressed . Spectra 100 400 N5=3 40 50 60 L (TeV) Simple Version(Linda Carpeter) 12

  14. (R. Gray, Somalwar, Park, Zhao, Thomas) Gauge Mediation with Split Messengers mwino(GeV) mwino(GeV) 400 500 400 500 Weak (pb) 7 TeV Total (pb) 7 TeV 60 60 N5=3 N5=3 Minimal Gauge Mediation Minimal Gauge Mediation 1200 50 50 40 40 d (TeV) d (TeV) mgluino(GeV) 1 800 30 30 2 5 20 0.8 0.7 0.6 0.5 20 10 400 20 40 50 60 40 50 60 L (TeV) L (TeV) (Most of Plane Not Excluded by Tevatron) 14

  15. Gauge Mediation with Split Messengers • Split GMSB Parameter Spaces Useful for Studies … (Gershtein, Shih, Thomas) Neutralino NLSP  , Higgs, Z + Goldstino(MET) Slepton Co-NLSP  Leptons, Tau+ Goldstino(MET) Stau NLSP  Tau + Goldstino(MET) Squark, Gluino  Jets+ Goldstino(MET) MetaStable Slepton, Stau  Massive - Charged Tracks MetaStable Gluino, Stop  Charge Exchange Tracks, … Metasble Neutralino, Slepton  Displaced , Higgs, Z , . Kink Tracks, … (R. Gray, Somalwar, Richards, Panwalkar, Contreras, Zywicki,Zhao, Park, Thomas) Rutgers Modification of IsaSugra 7.80 for Split GMSB can be Made Available to Anyone in CMS (Currently Beta Version , Backward Compatible) 15

  16. Physics Interpretation of Results (The Inverse Problem) • Benchmark Points, Lines, Manifolds, … Can be Useful for Presenting Null Results – . Quantify How Well Probe Specific Models . But Then Presentation of Results – Can Be Very Model Specific Unlikely to be as Useful if Postive Results - . Probably Won’t Capture All Features of Signal • Example – Tevatron Tri-Lepton Searches mSUGRA parameter space(see backup Slides for comments) Search Results in this form: Mapping from ¢Br Results . in Multiple Channels Onto . Model Spacen =0,1,2,3  16

  17. Physics Interpretation of Results (The Inverse Problem) • Benchmark Points, Lines, Manifolds, … Can be Useful for Presenting Null Results – . Quantify How Well Probe Specific Models . But Then Presentation of Results – Can Be Very Model Specific Unlikely to be as Useful if Postive Results - . Probably Won’t Capture All Features of Signal • Example – Tevatron Tri-Lepton Searches mSUGRA parameter space(see backup Slides for comments) Search Results in this form: Mapping from ¢Br Results . in Multiple Channels Onto . Model Spacen =0,1,2,3  Any Point in Model Space ) Model Dependent Correlation Among Spectrum, , and Br’s Information Lost 17

  18. Physics Interpretation of Results (Dube, Glatzer, Somalwar, Sood, Thomas) • Alternative Model Independent Method of Presenting Results . Factorize Mapping: Data  Model Space 1. Hypothesis for New Process * 2. Parameterize Experimental Acceptance or . ¢Br Sensitivity in Each Channel as . function of masses Only(Br’s=1) 3. Map Results Onto Any Model 18

  19. Physics Interpretation of Results (Dube, Glatzer, Somalwar, Sood, Thomas) • Factorized Mapping Method: Data  Model Space . (Solve the Inverse Problem) Simple Method to Probe Many Models . (Promises to be More Efficient Than Other Suggestions for . Filling Model Spaces with Full Mapping) Another Means to Present Experimental Results User Friendly (Theorist and Experimentalist) • Sensitivity Parameterizations for CDF . Tri-Lepton Results Available at (Steps 1 + 2) arXiv:0808.1605 [hep-ph] http://www.physics.rutgers.edu/pub-archive/0901/ • Plan to Quantify Multi-Channel Multi-Lepton Searches . in this Way (in Addition to Traditional Model Spaces) (R. Gray, Somalwar, Richards, Panwalkar, Contreras, Zywicki, Park, Zhao, Thomas) 19

  20. Top Quarks • Invariant Kinematic Distributions - . Extracting Top Quark Mass (Grasser, Shelton, Thomas, Lath, Halkiadakis, Schnetzer) Total e,  1/ d\dmbl ! e,  mb l Three Novel Methods for Extracting Top Mass from Templates 1. mblScale 2. mblShape 3. m l from b   20

  21. Top Quarks (Grasser, Shelton, Thomas, Lath, Halkiadakis, Schnetzer) Theory Study – Full Simulations . Needed to Generate Templates 21

  22. Top Quarks • MET Characterization/Calibration (Park, Lath, Thomas) W-Boson Leptonic Decay For Unpolarized pp  W X  l  X the pT Distribution of . Lepton and Neutrino are Identical . Even Though There is a Charge Asymmetry For Unpolarized pp  t t  b b l l  the . Vector Sum pT,1+2 Distribution of Lepton1+Lepton2 . and for Neutrino1 + Neutrino2 are Identical . Even Though There is a Charge Asymmetry Parton Level MET Distribution Identical to Vector Sum PT Distribution of Lepton1+Lepton2 Provides In Situ Measurable Handle on MET from Tops !! 22

  23. (Park, Lath, Thomas) Top Quarks Neutrino1 Neutrino1 + Neutrino2 Lepton1 Nuetrino2 Lepton1 + Lepton2 Lepton1 MET Lepton1 + Lepton2 Parton Level Dileptonic Top . 14 TeV . 130 pb-1 Gev Gev 1. Calibrate MET with Distributions in Top Dominated Control Region – 2.Search for New Physics Contamination from Deviations in Signal Region Technique for Tops Subsequently Adopted by Santa Barbara Group 23

  24. Top Quarks • Kinematic Invariants (Lath, Schnetzer, Hits, Thomas) … … Hadronic Top - Invariant Sub-Matrix Element Use NOT Common Mistake For i,j,k Jets from Hadronic Top Ordered List mij2 < mik2 < mjk2 mW22 (mij2 , mik2) Always Lowest Two Pairs mW2 mjk2 Never Highest Pair . (Ignoring Jet Resolution) 24

  25. Consistent On-Shell Effective Theory for Cascade Decay Correlations (COSET) (Thomas, Graesser, Shelton, Park) • Develop Effective Field Theory - . Calculate Cascade Decay Correlations • Systematic Expansion in /m , m/M • Provides Framework to Consider Wide Class . Standard Model + New Physics Processes . Correlations in Generalized Multi-Dimensional . Dalitz Spaces of Invariants Leading Order in COSET Expansion: Invariant Mass Distributions in Generalized Dalitz Space – . Uniquely Determined by Masses and Spins . (No Arbitrary Couplings) 25

  26. COSET – Sequential Two-Body Cascade Decay Correlations (Thomas, Graesser, Shelton) 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 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 26

  27. Discerning SUSY In Cascade Decay Correlations (Thomas, Graesser, Shelton) Limited Set of Possible Adjacent Branch Correlations : J=0, ½ Adjacent Di-Lepton Distributions– All Possible SUSY Spectra SUSY  Distinctive Patterns (Template) Search for Correlations in Data 27

  28. Next To Nearest OnShell Mass Extraction Technique (NNOMET) (Lath, Thomas, Park, Chavez) Correlations Uniquely Determined by Masses and Spins (SUSY) Three Sequential Cascade Decays m2jl Jets+ Leptons+MET m2ll m2jl Distribution In 3D Dalitz Space Uniquely Determined in Terms of 4 Mass Parameters  4 Sparticle Masses in Cascade Decay Tree d  / d mjl Includes Combinatoric “Non-Confusion” for Lepton1,2 Does Not Use Measurent of MET m2jl 28

  29. Next To Nearest OnShell Mass Extraction Technique (NNOMET) (Lath, Thomas, Park, Chavez) • LM1 Benchmark . TDR Cuts , 14 TeV , 100 pb-1 O(50) SUSY Events Likelihood Entropy Kinematic Mass Parameters A (GeV) Red – SUSY Decay SequenceBlue – SUSY “Combinatoric” Decay Sequence Green – SUSY + Top Background Form an Ensemble of All . Jets pT > 60 GeV + 2 Leptons Multiple Entries per Event B (GeV) Working to Extend to . Discovery Level … (S+S)/B» 1/3 29

  30. Next To Nearest OnShell Mass Extraction Technique (NNOMET) (Lath, Thomas, Park, Chavez) Multi-Dimensional Dalitz Space Distributions for n-Sequential Cascade Decays - Include All Possible Invariant Correlations Superior to Kinematic Edge, End Points, Special Points , … . (Strongest Correlations Washed Out in Projection) Can Test Hypotheses for Spin Assignments for n ¸ 2 . (n=2,3 Correlations from COSET List) Can Extend to n ¸ 3 . Very Strong Correlations in High Dimensional Dalitz Space . (n=2,3,4 Correlations for SUSY From COSET List) Physics Based Correlations – Directly from COSET Formalism . (Extracting from Neural Net Seems Hopeless) For n-Sequential Cascade Decays , n=1,2 . NNOMET Can Not Reconstruct All Masses . (Techniques That Use MET May Be Useful in These Cases) 30

  31. jet jet jet jet jet jet Extracting Hadronic Resonances Using Jet Ensemble Correlations (Duggan, Hidas, Bavier, Halkiadakis, Lath, Thomas) Purely Hadronic Final States Very DifficultGreat Discovery Potential … Cut mjjj pp  QQ j j j Accept j j j ~ SUSY – Hadronic RPV Q= g pT,jets Standard Techniques Fail on High Multiplicity Final States QCD Fills Up Phase Space !! Accept Combinatoric Confusion Form Ensemble of Permutations Invariant- Non-Invariant Correlation Extend to Other Signatures … 7 TeV 10 pb-1 31

  32. Conclusion We Theorists are Here to Contribute Constructively … 32

  33. Back Up Slides 33

  34. Benchmarks / Parameters Spaces • Pre-Discovery: • Generators for Signatures – Develop + Optimize Searches • Every Benchmark has Particular Details – . Easy to get too Invested • Theory: • Designed to Probe Underlying Theoretical Framework - . But Actual Benchmark = Arbitrary Subspace of a . Contrived Model with Hidden Uncontrolled Assumptions … • Experiment: • Possible to Over Specialize / Optimize Search Strategy . Or Neglect Interesting Signatures Based Benchmark Details . (e.g. Constrained SUSY Based on Higgs mass, …) • Post-Discovery: • Don’t Try (Too Hard) to Jam Positive Results into Benchmark 34

  35. Benchmarks / Parameters Spaces • mSUGRA is Probably the Most Widely Abused . Benchmark / Parameter Space Messenger Scale O(Mp) “Perfectly Good” Theoretical . Framework for SUSY Breaking (Hall, Lykken, Weinberg) • mSUGRA Perfectly Good Generator for Jets+Leptons+MET But it is an Arbitrary Subspace Defined at an Inaccessible Scale Within a Contrived “Model” with Hidden Uncontrolled Assumptions So Don’t Take Fine Details Too Seriously – e.g. Higgs Mass 35

  36. Benchmarks / Parameters Spaces If You Don’t Believe Me - . Ask Him . Yourself • mSUGRA is Probably the Most Widely Abused . Benchmark / Parameter Space Messenger Scale O(Mp) “Perfectly Good” Theoretical . Framework for SUSY Breaking (Hall, Lykken, Weinberg) • mSUGRA Perfectly Good Generator for Jets+Leptons+MET ?? But it is an Arbitrary Subspace Defined at an Inaccessible Scale Within a Contrived “Model” with Hidden Uncontrolled Assumptions So Don’t Take Fine Details Too Seriously – e.g. Higgs Mass ?? OK ?? Please Describe with Relevant Parameters(not m0 , m1/2 ) 36

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