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Status Report: Search for SUSY in the Jet+MET+Tau Final State

Status Report: Search for SUSY in the Jet+MET+Tau Final State. Jonathan Asaadi , Alfredo Gurrola, Seema Sharma**, Sinjini Sengupta*, Teruki Kamon, and David Toback Texas A&M University ** Fermilab * University of Minnesota. SUSY in the Jet+MET+ t Final State .

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Status Report: Search for SUSY in the Jet+MET+Tau Final State

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  1. Status Report: Search for SUSY in the Jet+MET+Tau Final State Jonathan Asaadi, Alfredo Gurrola, Seema Sharma**, Sinjini Sengupta*, Teruki Kamon, and David Toback Texas A&M University ** Fermilab * University of Minnesota

  2. SUSY in the Jet+MET+t Final State Reminder : Why we are looking at the Jet+MET+t final state If astronomical observations are correct and experimental constraints prove to be true Gives us the Final State Jets+MET+Tau We may live in a SUSY Co-annihilation world Jets MET Tau Important Early Universe Feynman Diagram For High Tan(b) Co-annihilation Process

  3. Outline for the Talk • Overview of the tools we use and their status • Data Samples • Object Id • Physics Analysis Tools (PAT) • SUSY PAT • Progress made using the tools • Incorporating Tau information • Ongoing optimization study • Conclusions / Next Steps

  4. Tools We will highlight the two CMSSW releases and the status of the tools in those releases CMSSW 1_6_12 (Preliminary Study nearly Complete) CMSSW 2_2_0 (Work on Going…) Data Sets • Data Samples in 1_6_12 • CSA 07 Samples (14 TeV C.M. Energy) • SUSY LM2 • Gumbo (QCD + Photon + Jets) • - Chowder (W, Z, tt-bar + Jets) • Data Sets • - Supersymmetry Low Mass Point 2 (SUSY LM2) • QCD • W + Jets • t t-bar + Jets • Z + Jets Discuss status / problems of each set… • Data Samples in 2_2_0 • Summer 08 Samples (10 TeV C.M. Energy) • SUSY LM2 • QCD Di-Jet (Pt bins 0-3500 GeV) • MadGraphW+Jets • MadGraphtt-bar + Jets • MadGraph Z + Jets (not yet in my sample)

  5. Data Samples in 1_6_12 These are the data samples that we have used to provide signal and background for our study (The data samples used in 1_6_12 have a known bug with incorrectly calculating the decay of heavy quarks and thus events where this bug is present are tossed out) In order to generate these soups by mixing processes with different cross-sections the CSA07 weight producer was implemented to normalize all cross-sections for the different process for each event to 1000 pb-1 (1 fb-1) These data samples are well tested and successfully used, however lack much of the progress made with object Id in newer releases

  6. Data Samples in 2_2_0 See backup slides for full description of errors known to give problems (Duplicate Event, PF drop, etc…) A major problem is that Particle Flow information had to be dropped from these original samples…Re-reco in progress, but takes time and alternative methods have proved troublesome Jonathan Asaadi Texas A&M

  7. Data Samples • Data Samples working! • Known fixes to existing bugs • Well tested samples • Older version of Object Id present and incompatible with new CMSSW • Data Samples in 1_6_12 • CSA 07 Samples • SUSY LM2 • Gumbo (QCD + Photon + Jets) • - Chowder (W, Z, tt-bar + Jets) • Data Samples compiled but not in ideal state • Particle Flow Information not ready in complete standard version • Many existing known bugs in samples…but effects not fully understood • Complete set except for Z + Jets compiled for use with our analysis • Data Samples in 2_2_0 • Summer 08 Samples • SUSY LM2 • QCD Di-Jet (Pt bins 0-3500 GeV) • MadGraphW+Jets • MadGraphtt-bar + Jets • MadGraph Z + Jets

  8. Object Id Overview of the Object Id’s used for this analysis Input Reconstructed Data Jets - Constructed from calorimeter information using algorithms found in the Physics Analysis Tools (PAT) Tau - Constructed from Particle Flow information using algorithms found in the Physics Analysis Tools (PAT) MET - Constructed from calorimeter information using algorithms found in the Physics Analysis Tools (PAT) Jet Tau MET Works in both PAT 1_6_12 & 2_2_0 Problems encountered in both 1_6_12 and 2_2_0 Works in both PAT 1_6_12 & 2_2_0 The PAT::Tau works in 1_6_12, however there in no Monte Carlo matching in this release and there have been many improvements to the Particle Flow Algorithms not found in this release The PAT::Tau has had many improvements in 2_2_0 however its function is currently limited by problems in the data samples…so for now we use CaloTau definition Jonathan Asaadi Texas A&M

  9. Physics Analysis Tools (PAT) This is a framework that allows data from reconstruction (RECO) to be collapsed into Physics Objects (Jets, Taus, Muons, etc…) using standard identification tools and a uniform environment • PAT Layer 0 • Monte Carlo Matching • Cleaning of Object Association • Trigger Matching • PAT Layer 1 • Production of standard physics objects from Layer 0 information using Particle Object Group (POG) definitions RECO Data Both 1_6_12 and 2_2_0 releases have been used and validated by PAT experts. We have compared output from PAT 1_6_12 to results given for similar analysis using private tools Similar Validation of PAT output in 2_2_0 is currently underway

  10. SUSY Physics Analysis Tools (SUSY PAT) This is a framework that allows a user to plug into the output from the PAT and use different standard event selectors and event hypothesis variables to perform different studies in a uniform environment • SUSY PAT • Various Event Selectors (TauEventSelector, JetMETSelector, etc…) • SUSY PAT Cross-Cleaner • Generate SUSY specific variables (MT, MHT, Mtt) • End-User-Output • Flat Ntuple Outputkeeping only SUSY event specified variables PAT Layer 1 Output Both 1_6_12 and 2_2_0 releases have been used by end users successfully with rigorous comparisons ongoing. Some issues with getting SUSY PAT and the cross-cleaner to work in different releases of 2_2_X have been worked with and need to be documented

  11. Summary of the Tools • Many of the tools for our analysis exist in one form or another in both releases 1_6_12 and 2_2_0 • However, there have been many problems with the standard tools (e.g. Particle Flow information in new data sets) in newer releases • Many of the workarounds will allow progress, but can result in results that are environment dependent and difficult to physically interpret Changing Gears: Moving to discussion of what we have done with the tools

  12. Incorporating Tau Information into the SUSY PAT One of the tasks we took over was to us to incorporate tau information from the PAT into the SUSY PAT • Tau Event Selector 1_6_12 • Bases Tau Id on Particle Flow Definitions • Selects events based on kinematic Tau Id Variables • Outputs useful tau related variables (e.g. Di-Tau Invariant Mass We completed this task (Plots on the next page) Do to a lack of Monte Carlo Matching available for Tau objects in this release we were unable to perform efficiency studies based on our selector • Tau Event Selector 2_2_0 • Bases Tau Id on Improved Particle Flow Definitions • Selects events based on kinematic Tau Id Variables • Outputs tau related variables (e.g. Di-Tau Invariant Mass This task has been impeded by problems with data samples…using CaloTau definition to make progress

  13. Plots from CMSSW 1_6_12 Tau Plots Produced for LM2 SUSY Point: Tau Signal Tracks Excess in 1 – 3 prong tracks New Results: Using improved PF definitions over entire sample Tau # of Signal Tracks Tau Pt Tau h Resonableh distribution h Tau Pt (GeV)

  14. Tau Plots: Comparing Results to CMS TDR Produced for LM2 SUSY Point: Event Selection Missing Et > 150 GeV NTau> 1 NJet with Et > 150 GeV DR between any tau pair <= 2 (Not implemented in my selection…) Plots from CMSSW 1_6_12 New Results: Using improved PF definitions over entire sample Good Agreement between TDR and our result (see backup slides for opposite sign minus like sign result)

  15. Toy Optimization Study for SUSY LM2Why we wanted to do this study? • Once we had written our Tau Event Selector for the SUSY PAT we wanted to assess if we have all the tools necessary to step through an analysis • We do this by studying the effectiveness of different variables in optimizing (signal / sqrt (background)) for 100 pb-1 of data • This allows us to study what variables we should be looking at to improve our sensitivity and what tools we need to develop • Only spend time developing the tools that matter Do we have the tools to go all the way through this process?

  16. Toy Optimization Study for SUSY LM2What we did in each release? • Optimization in 1_6_12 • Using the various event selectors in the SUSY PAT we select a pre-sample and then assess which variables improve our sensitiveity the most (Plots on the next pages) • This involved writing a few new selectors to reject known buggy events and to explore various variables • Optimization in 2_2_0 • Attempt to use the same tools with this framework and the new data sets • Despite the data samples causing a slight difference in our object Id we have begun this study in CMSSW 2_2_0 • Looking to do a comparison in results • Preliminary event reduction table with full set of plots coming soon!

  17. The Optimization Calculation Note: These are 1_6_12 definitions of the data samples Ask the simplest question: What single cut helps the most? Note: QCD dominates in our Pre-Sample cuts Note: These results are for CMSSW 1_6_12

  18. Looking at many different variables • We are interested in doing an analysis using our experience from the Tevatron • Don’t want to reinvent the wheel…instead try start with known smart things and build from there • We want to do a robust analysis and plan on exploring variables used in other squark and gluino searches done as well as looking at variables used in earlier studies Variables used in earlier studies New variables to explore Variables used at the Tevatron

  19. - Yes We want to keep the Pt as low as possible and still have confidence in our tau identification Does a Tau Help? Signal + Gumbo + Chowder Gumbo + Chowder Chowder Does a MHT Help? A Big Improvement Signal + Gumbo + Chowder Gumbo + Chowder Chowder See backup slides for event reduction table

  20. Does a Help? Not as much as MHT and MET…might need to write a standard aT event selector for the SUSY PAT (does not exist yet) Does MET Help? Signal + Gumbo + Chowder Gumbo + Chowder Chowder Yes… Signal + Gumbo + Chowder Gumbo + Chowder Chowder See backup slides for event reduction table

  21. Does df1 Help? Some, but this is without applying a MET cut first Does R1 Help? Signal + Gumbo + Chowder Gumbo + Chowder Chowder Yes, …without the initial MET cut this does about the same cut as df1 cut Signal + Gumbo + Chowder Gumbo + Chowder Chowder See backup slides for event reduction table

  22. Summary of Optimization(so far…) Results from CMSSW 1_6_12 • This is not a complete list of all the variables we have/plan to explore • Just a snapshot of what we’ve done and where we are going • Going to start looking at these cuts in combination…see future talks for details

  23. The Optimization for 2_2_0 Results from CMSSW 2_2_0 • Need to include Z + Jets Sample • - Beginning the work to run our tools over these samples!

  24. Conclusions • Much progress has been made using the standard tools • Work done with the Tau Event Selector shows agreement with CMS TDR • Able to walk through the first parts of an optimization using these tools • A lot of work left to do to use these tools on new data samples in 2_2_0 • Currently working through several bugs to produce results in this release • Working to develop additional tools as we see a need Next Steps • Finish our results in 1_6_12 putting cuts together to see what helps the most • To further develop our Tau Event Selector in 2_2_X and study with reprocessed data samples as they become available • Complete the toy-optimization study in 2_2_0 for full comparisons • Continue developing additional tools for use with the SUSY PAT in 2_2_X

  25. Backup Slides

  26. Error result in reduction in number of event Data Samples in 2_2_0 Problems Currently Known: (possibly more unknown) • Particle Flow information not available in samples run in 2_2_0 • Correction to this to be implemented in the coming months • Workaround offered by Particle Flow experts …still needs to be tested in our own samples…in the meantime any events that throw an error due to PF information are discarded • This means that CaloTaus are currently the default setting for the PAT in 2_2_0 (different from PFTaus in 1_6_12) • Duplicate Events message error • In TTJets and W Jets Madgraph samples a number of events give an error of having duplicate run number and are simply skipped over during the run • Problem resolved after samples were initally run…need to turn off duplicate check setting for all MadGraphSamples https://hypernews.cern.ch/HyperNews/CMS/get/physTools/903/1.html for more details • EcalRecHit error present in the samples known to be giving large tails in the MET distribution Work with these data samples and the new releases is continuing and status and progress can be seen in other talks See the following links for Reference: https://twiki.cern.ch/twiki/bin/view/CMS/ProductionSummer2008 http://mthomas.web.cern.ch/mthomas/Summer08ProductionRECOglobal.html Jonathan Asaadi Texas A&M

  27. Particle Flow Taus(In General) Particle Flow Tau ID # of Tracks in Matching Cone with Pt > 5.0 GeV 1 # of Particle Flow Photons with Pt > 1.0 GeV in Isolation Annulus = 0 # of Particle Flow Charged Hadrons with Pt > 1.0 GeV in Isolation Annulus = 0 - Check to see if leading charged hadron is an electron or muon • The Particle Flow Tau List is generated from the Particle Flow Jet List DR = 0.1 DR = 0.5 DR = 0.1 Taken from Tau Identification in CMS TWiki: https://twiki.cern.ch/twiki/bin/view/CMS/SWGuidePFTauID J.Asaadi PF Vertical Integration Meeting

  28. M ttos-ls Plots from CMSSW 1_6_12

  29. Does a Tau Help? Jonathan Asaadi Texas A&M

  30. Does MHT Help? Jonathan Asaadi Texas A&M

  31. MET Jonathan Asaadi Texas A&M

  32. Does Alpha Help?

  33. Does df1 Help?

  34. Does R1 Help?

  35. The Optimization for 2_2_0 Note: These results are for CMSSW 2_2_0

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