Jim Linnemann, Michigan State Recent Tevatron Searches: Large Extra Dimensions, SUSY, and other New Phenomena Jim Linnemann, Michigan State For DØ and CDF Moriond EW La Thuile, Italy, March 23, 2004

Overview Tevatron LED, Z, miscellany and SUSY Emphasize updates since LP 03 We are starting to see a flood of new results! Shortchanging older analyses Will also skip some interesting new analyses—time Showing limits (alas) at 95% CL In a mixture of prescriptions

Large Extra Dimensions: Strategies ee, and EM = e+γ Central + central-end end-end has big QCD bkg 2-D M, Cos θ* fit Fit C-C and C-E separately to background + model Model: specific processes CDF ee Central + central-end mostly Likelihood fit to M Cos θ* is a cross-check Spin-dependent σ·B limits beyond SM Interpret in many models

Large Extra Dimension Searches DØ 2-D model-specific fit CDF σ ·BSpin limits Spin = 2 (example)

LED signal limits New limits from both DØ & CDF L= 200 events/pb ηG95 = F/M4S parameterizes ED effects Limits using GRW: F=1 = HLZ n=4, F = 2/(n-2) =1 CDF II Ms > 1.11 TeV DØ II Ms > 1.36 TeV DØ I + II Ms > 1.43 TeV most restrictive to date LED signal MC “bump” looks like statistics, not signal fakes L = 200 / pb Bkg

Dedicated ee Search for TeV-1 Dimensions Model: fermions on 3d SM gauge bosons in bulk of branes M2n= Mo^2 + n2/M2c KK towers extra virtual effects Negative Interference effects unlike LED Find: Mc > 1.12 TeV (95% CL) First direct search Indirect searches: LEP: > 6.6 TeV; all: > 6.8 TeV Jet mis-ID Mc signal SM + mis-ID

Z Limits from ee: SM, E6 CDF: use spin 1 acceptance DØ: Pythia Z Optimize window vs. MZ Limits in Aσ/σZ SM Couplings Run I SM Run II CDF : 690 750 DØ: 670 780 E6 ZI Zχ Zψ Zη CDF II: 570 610 625 650 DØ: 575 640 650 680 Some difference from σZ’ calculations Caveat: DØ: K(MZ), K= 1.19-1.46 actually, using NNLO + M-dependent K factor. Mass dependence increases limit by perhaps 5 GeV CDF: K = 1.30, but wrt different LO X section

CDF Forward ee? DØ sees 1 event > 450, .9 ± .2 SM expected

LED with jets + MET: DØ update (L= 85/pb) Consider G radiation Monojet-like J1 > 150, J2 < 50, MET > 150 ΔΦJ,MET > 30o Observe 63; expect 100 ±6±7 -37 “signal” Signal Limit = 84 events expected 128 ± 28—a bit lucky? Includes large energy scale uncertainty Both MC and Data scales! Efficiency: 20% Background: +50% and –30% K=1 Better than Run I, but need better Jet Energy Scale

Other CDF limits from ee Reinterpret Spin 0, 1, 2 σ·B limits in various models .05 to .2 pb (mass, spin dependent) Examples: little higgs RPV sneutrino R-S graviton techni rho: more data needed Non-optimal is still useful ! From TOF (not ee): Mstop > 95 “Champ” Analysis

DØ Jets + MET SUSY interest: LSP escapes as MET Light squarks decay to q LSP Light gluinos: decay to qqbar LSP (more jets) acoplanar, but not monojets Require acoplanar topology: j1 > 60 j2 > 50 opposite of LED ΔΦj,MET > 30o ΔΦjj < 165o Optimize MET, Ht: σLimit / σs σs is typical mSUGRA signal use: M0 = 25, M½ = 130 Choose: MET > 175, HT > 275

Squark Gluino Limit Status Expect 2.7 ± 1.0 SM efficiency ~ 5% See 4 events with L=85/pb Analysis better optimized for light squarks than light gluinos Results of M½ scan with Mo = 25, Ao = 0, tan β = 3, μ < 0 For Msquark ~ 290, Mgluino > 333 Already better limit than Run I better QCD rejection data, MC) +25%, -15% efficiency; +77%, -43% background

SUSY trilepton search: DØ Chargino + N2; masses ~ 2 MLSP Decay to WZ or sleptons +2 LSP Low mass sleptons: good BR Gold plated: trileptons 2 like-sign available BUT: Signal a bit thin on the ground σ·B < 1pb low chargino mass: soft leptons LEP II cleared a good bit of mSUGRA space Strategy: Combine ee, μμ, eμ: tune cuts for low background

Like Sign μμ with 147/pb μ1 > 11, μ2 > 5 isolated MET > 15 Kinematics to kill Z M < 80 sign flip avoided exclude Z if have μ+μ- pair And QCD b and c+ν decays ΔΦμμ < 2.7 If μ2 < 11, tighten further: .5 < ΔΦ μ,MET < 2.4 ΔΦμj < 2.4 not fully optimized, but blind Expect .13 events; observe 1 σ·B SUSY ~ .2 to .4/pb: ε ~1% .2 to .4 SUSY events expected B/c background in LS checked by using same method to estimate background in OS low-mass data b background scaled from like-sign data non-isolated μ’s

SUSY eμ L = 158/pb e >12 μ > 8 isolated WW, Wj prevention: 15 < MET < 80 tighter ID near MT (W) 10 < Meμ < 100 |e, μ, MET| > 6 ~ pT(l3) Expect 2.9 ± .4 See 1 event can also require: Iso Track > 3 weak 3rd lepton Expect 0.5 ± .2 See 0 events SUSY: .6 to .9 events for either (little loss due to isolated track) Before pT(l3) cuts

SUSY ee with L = 174/pb e > 12, 8 one central MET > 20 track >3; ΔRe,tr > .4 3rd lepton Kill Z, top by kinematics irritating SM backgrounds already! jets < 80 Mee < 60, ΔΦee < 2.8 Mt >15; ΔRe,MET > .4 tr  MET > 250 Expect SM .3 ±.4; observe 1 Signal: .8 to 1.6 events

η φ Et e Friday the 13th Event track 33.2 -.97 3.37 25.7 -2.19 2.97 8.6 .67 5.87 MET 52.1 .12

DØ combined lepton limits SUSY Scan M0 M½ A0 = 0, tan β = 3, μ < 0 72 165 74 168 76 170 80 175 180 88 185 .4 to 2 pb σ·B SUSY typically 2-3 events . CLs combination of 3 channels including correlations Channel Data SM  stat  syst. L/pb eel 1 .27  .42 .02 174 eμl 0 .54  .24 .04 158 eμ 1 2.49  .37  .18 158 μ+μ+ μ-μ- 1 .13  .06  .02 147

SUSY Limit Results Better than Run I σ·B < .5pb Not quite excluding predictions

Summary Nature declined to flood us with new phenomena so far Clear improvements over Run I are visible L ~ 200/pb x 2 and counting apparatus understood well enough to use it Not fully optimized but already have σ·B <.5 pb –or better- limits e.g. sensitive to 10 events @ ε~10% Publications in our near future buon appetito!