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SUSY Tevatron Results and Physics Potential. Andy White – University of Texas at Arlington for the D0 and CDF Collaborations. Contents. SUSY in Run I at the Tevatron - examples of analysis – not comprehensive - parameter space access/coverage Tevatron Run II
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SUSY Tevatron Results and Physics Potential Andy White – University of Texas at Arlington for the D0 and CDF Collaborations Andy White Physics at LHC Prague, July 2003
Contents • SUSY in Run I at the Tevatron - examples of analysis – not comprehensive - parameter space access/coverage • Tevatron Run II - D0/CDF detector upgrades - Accelerator, luminosity • SUSY in Run II at the Tevatron - Analyses started - Physics potential Andy White Physics at LHC Prague, July 2003
SUSY Cross sections are small ! Indicated points are for m1/2= 150 GeV m0 = 100GeV A0= 300 GeV tan = 4 >0 Cross sections (pb) Andy White Physics at LHC Prague, July 2003
SUSY in Run I • - Energy 1.8 TeV • ~ 100 pb-1 of data analyzed • Many channels studied: • “Classic” SUSY - Jets and Met • Squarks + gluinos with leptonic decay(s) • Gaugino production, leptonic decay • Stop, Bottom • “Alternatives” e.g. GMSB, RPV,… Andy White Physics at LHC Prague, July 2003
Some examples from Run I CDF D0 Andy White Physics at LHC Prague, July 2003
mSUGRA parameter space coverage D0 Andy White Physics at LHC Prague, July 2003
Run II SUSY/Higgs Workshop hep-ph/0003154 Typical Run I results Andy White Physics at LHC Prague, July 2003
Stop and sbottom searches Andy White Physics at LHC Prague, July 2003
Stop and sbottom searches Andy White Physics at LHC Prague, July 2003
D0 results for RPV SUSY – tri-leptons Reinterpretation of trilepton gaugino pair production results for mSUGRA with R-parity, Lepton number violation. LSP -> Leptons ijkLiLjEkC Enhanced multilepton events Li Andy White Physics at LHC Prague, July 2003
CDF – a hint of something new from Run I ?? • - Low probability from SM sources – model independent study with l, , MEt. • Subject of much speculation! GMSB explanation: Gravitino LSP? • Motivation for many searches in Run II Andy White Physics at LHC Prague, July 2003
Run II at the Tevatron • New accelerator components – Main Injector • Upgraded D0 and CDF detectors • Higher beam energies – larger cross-sections • Substantially expanded worldwide participation • SUSY analyses underway for D0 and CDF • Predictions for Runs IIa, IIb from Fermilab Workshop, e.g. SUGRA in hep-ph/0003154. Andy White Physics at LHC Prague, July 2003
CDF upgrades for Run II Andy White Physics at LHC Prague, July 2003
CDF improvements for SUSY searches • New tracking system (Si and central) • Extended coverage for electrons and muons • New forward (plug) calorimeter improves Met • TOF for charged massive stable particles • New/improved triggers for MEt, Andy White Physics at LHC Prague, July 2003
New forward components of the D0 detector Intercryostat detector Forward pre-shower Andy White Physics at LHC Prague, July 2003
D0 improvements for SUSY searches • Solenoid + completely new tracking added • Improved muon tracking and triggering • Improved electron id. (preshowers) • Central track trigger • Triggering on b jets • New Intercryostat Detector (jets, MEt) Andy White Physics at LHC Prague, July 2003
Run II SUSY Searches • Examples of Run II results here are from Winter/Spring conferences – expect significant updates, increased Ldt this summer. • Both experiments use two approaches: Theory/model motivated analysis Model independent analysis Optimize analysis with model studies Generic search – “safety net” Andy White Physics at LHC Prague, July 2003
Jets + MEt The challenge: QCD (jets) -> high rate -> residual tail. D0 - study with 4 pb-1 has shown that, with cuts to reduce fake MEt, the tail can be understood. Andy White Physics at LHC Prague, July 2003
Jets + MEt expectations Run II 2 fb-1 search region hep-ph/0003154 Andy White Physics at LHC Prague, July 2003
Photons + MEt Gauge mediated SUSY breaking (GMSB) with light Gravitino LSP can yield + MEt: where N is next-to-lightest SUSY particle. Andy White Physics at LHC Prague, July 2003
Observe 2 events, expect bkg 2±2 events CDF Run II From S-W Lee/SUSY 2003 M = 2, N5 = 1 tan = 15, > 0 Andy White Physics at LHC Prague, July 2003
66 GeV limit from ~50 pb-1 D0 Run II M = 2, N5 = 1 tan = 15, > 0 Andy White Physics at LHC Prague, July 2003
Tri-lepton final states ’s ! Andy White Physics at LHC Prague, July 2003
Tri-lepton final states 42 pb-1 Di-electron sample + cuts Efficiencies ~ few percent Will improve over LEP-2 with >300 pb-1 Andy White Physics at LHC Prague, July 2003
Tri-lepton final states Studies for channels D0: Z -> -> (e) + (h) • Pt(e) > 12 GeV isolated • Pt(jet) > 7 GeV • - Jet/e not back to back • - Cut on Z -> ee • Use Neural net for tau id. D0 Run II preliminary 50pb-1 Andy White Physics at LHC Prague, July 2003
Tri-lepton final states CDF: Z -> Andy White Physics at LHC Prague, July 2003
Tri-lepton final states “Soft cuts” to pick up ->e, . Cuts varied to optimize S/B. Dilepton plus Tau jet Andy White Physics at LHC Prague, July 2003
D0 model independent search in e + … • - Results from ~30 pb-1 • - SM + mis-ID backgrounds • Main bkgds Z->, WW, tt • - Derive limits vs MEt cut Andy White Physics at LHC Prague, July 2003
D0 model independent search in e + … 100 fb Andy White Physics at LHC Prague, July 2003
Long lived Stop from TOF CDF: GMSB with NLSP stable Stop particle. t > 2.5 ns, Pt > 40 GeV/c Expect 2.9 ± 0.7 ± 3.1 ev. Observe 7 events M(Stop) > 108 GeV/c2 at 95% CL (Aleph M(Stop) > 95) Andy White Physics at LHC Prague, July 2003
Stop, sbottom in Run II Andy White Physics at LHC Prague, July 2003
CONCLUSIONS • Many interesting results from Run I at O(100 pb-1) • Energy and Luminosity upgrades for Tevatron • Large scale D0 and CDF detector upgrades - detectors fully commissioned and taking data with high efficiencies. • Comprehensive program of SUSY searches for Run II – window(s) of opportunity before LHC! Andy White Physics at LHC Prague, July 2003
Fermilab Run II Accelerator Systems Andy White Physics at LHC Prague, July 2003
5 discovery curves ~ one year at 1034: up to 2.8 TeV ~ one year at 1033 : up to 2.3 TeV ~ one month at 1033 : up to 2 TeV F. Gianotti: talk at D0 Summer 2003 Workshop, Beaune, France Andy White Physics at LHC Prague, July 2003