J.-F. GrivazSUSY-06 June 16, Search for Physics Beyond the Standard Model at the TeVatron Jean-François Grivaz (LAL-Orsay) for the CDF and DØ Collaborations

J.-F. GrivazSUSY-06 June 16, Beyond the Standard Model: Enlarge the gauge group  Z’, W’ (*) Alternative EWSB mechanisms (TC, little Higgs) (*) Relate quarks and leptons  Leptoquarks Extend Poincaré  Supersymmetry and include gravitation (Supergravity) Increase the number of dimensions (*) Repeat the history (compositeness) (*) = Not covered today (in 30’) The Standard Model: SU(3) c x SU(2) L x U(1) Y The Higgs mechanism Three generations of quarks and leptons The Poincaré group In a 4-dimensional space-time

J.-F. GrivazSUSY-06 June 16, At the TeVatron : p-pbar collisions at 1.96 TeV c.o.m. energy Peak luminosity: > 1.7 E32 cm -2 s -1 Delivered: > 1.5 fb -1 In this talk: 0.2 to 1.1 fb -1 DØ: CDF: Main Injector Tevatron DØCDF Chicago   p source Booster Unless there are good reasons, I’ll pick examples in either one. Still the energy frontier

J.-F. GrivazSUSY-06 June 16, New Gauge Bosons

J.-F. GrivazSUSY-06 June 16, Extra Gauge Bosons M(Z’-seq.) > 850 GeV (somewhat lower limits in) (canonical E(6) models) M T = M(electron-p T,missing-E T ) M(W’-seq.) > 788 GeV e.g., W’ in L-R models Z’ within E(6) GUTs Beauchemin

J.-F. GrivazSUSY-06 June 16, Supersymmetry

J.-F. GrivazSUSY-06 June 16, SUperSYmmetry At such a conference, no “What is SUSY ?”, or “Why SUSY ?” Which SUSY ? More or less constrained MSSM, à la mSUGRA neutralino-LSP with or without R-parity violation Gauge Mediated SUSY Breaking gravitino-LSP and neutralino-NLSP Anomaly Mediated SUSY Breaking wino-LSP and long-lived chargino Split SUSY long-lived gluino

J.-F. GrivazSUSY-06 June 16, (m)SUGRA Two main search streams at the Tevatron: Squarks and gluinos  multijets + missing E T large production cross sections large experimental backgrounds Electroweak gauginos with leptonic decays (Trileptons) low production cross sections typically low leptonic branching ratios clean experimental signature m 0 m 1/2 tan(  ) A 0 sign(  )

J.-F. GrivazSUSY-06 June 16, Trileptons Arise from chargino-neutralino associated production “Golden” SUSY signature but: - low cross sections (  BR) - soft leptons - taus (at large tan  )  Needs large integrated luminosity  Combine various final states (Also decays via W/Z exchange) General strategy (similar in CDF and DØ): Two isolated (rather soft) e or  Require some Missing E T (  )  channel-dependent cuts (e.g. anti Z,  ) - An isolated third lepton or track (sensitive to  ’s), or - Two same sign leptons Main backgrounds: DY, WW, WZ, W  (+ a bit of bb and mis-ID) StrologasHohlfeld

J.-F. GrivazSUSY-06 June 16, CDF Analysis Lumi (pb -1 ) Total predicted Background Observd data e  e ,e   ,       +e/  (low-p T )  ee+track  ee + e/    +e/    e +e/   DØ Analysis Lumi (fb -1 ) Total predicted Background Observd data ee+track   +track  e  +track  SS   e  +track   +track  The results of the various channels are combined, “weighted” according to their sensitivity, with overlaps taken into account. Cross-section upper limits & mass lower limits within specific models. Missing E T in  +e/  Missing E T  p T (3) in ee+track …and in the end…

J.-F. GrivazSUSY-06 June 16, m 0 = 60 GeV  2-body decays enhanced (  ) s  mixing on (  s  L component)  decays to  ’s enhanced (  ) Models = “favorably tweaked” mSUGRA Both CDF and DØ set m s  = m se = m s  m(sl) = m(  2 0 ) +   only 3-body decays (  ) s  mixing off (no s  L component)  decays to  ’s = to e/  (  ) Some work ahead for the TEV-WG…

J.-F. GrivazSUSY-06 June 16, Generic squarks and gluinos Strong production (  Large cross sections ) of: sq-sqbar and sq-sq  at least 2 jets + missing E T (sq  q  ) gl-gl  at least 4 jets + missing E T (gl  qq  ) sq-gl  at least 3 jets Cascade decays complicate the picture  model needed (mSUGRA) DØ three analyses optimized for each of these processes reduces QCD to a negligible level CDF 3-jet analysis optimized mostly for m(sq)  m(gl) larger QCD background, estimated from control regions Main backgrounds: Instrumental (QCD multijets with fake missing E T ) (W  (missed lepton)+ ) +jets (also from ttbar) (Z  ) +jets (irreducible) Martinez Bargassa

J.-F. GrivazSUSY-06 June 16, Main analysis cuts: Data cleaning Jet1,2(,3(,4)) p T Missing E T H T = sum of jets p T ’s Lepton veto Angles (jet,missing E T ) Analyses Background expected Events observed DØ  2 jets4.8  DØ  3 jets3.9  CDF  3 jets8.2  DØ  4 jets10.3  H T  225 GeV (m(gl)=240 GeV)

J.-F. GrivazSUSY-06 June 16, M gl > 387 GeV (when M gl ~M sq ) M gl > 241 GeV & M sq > 325 GeV You have seen or will see other versions of this plot. CDF vs DØ differences: 371 vs 310 pb -1 tan  = 5 vs 3 (little impact) 4 vs. 5 flavors (little impact) Theoretical uncertainty on the signal cross section: CDF includes it as a systematic uncertainty in the computation of the cross section limit DØ reduces instead the theoretical cross section by its uncertainty (more conservative): yellow band …and CDF was a bit lucky. Some work ahead for the TEV-WG…

J.-F. GrivazSUSY-06 June 16, st R Stop A light stop can be expected: top-Yukawa impact in RGE First scenario considered by DØ: (relevant as long as m(st) < m(b)+m(W)+m(  )) (in SUGRA, needs M1 < M2 at GUT scale)   1 c-jet (soft tag) + missing E T (optimized for various m(st),m(  )) Main backgrounds: W/Z+jets + Large L-R mixing stop NLSP and  LSP with st  c  (FCNC) m(st) = 130 GeV m(  ) = 50 GeV Bargassa

J.-F. GrivazSUSY-06 June 16, Light sneutrino  st  b l s  2 leptons (+b-jets) + missing E T (s  ) (optimized for various m(st),m(s )) Stop exclusion up to m(top) Second scenario considered by DØ: e  and  final states analyzed Main backgrounds: Z  at low mass, top at high mass e  analysis: S T =p T (e)+p T (  )+missing E T with two signal examples Stop Bargassa

J.-F. GrivazSUSY-06 June 16, Sbottom A light sbottom can be expected at large tan . DØ searched for sbottom pair production, with sb  b    1 b-jet + missing E T (optimized for various m(sb),m(  )) CDF searched for sbottom from decays of pair-produced gluinos: gluino  b sb (100%)  3/4 b-jets + missing E T With 156 pb -1, sbottom masses up to 240 GeV are excluded IF m(gluino) < 280 GeV (and m(  ) = 60 GeV) m(sb) = 140 GeV m(  ) = 80 GeV Bargassa Martinez

J.-F. GrivazSUSY-06 June 16, R-parity violation Possible additional terms in the superpotential: With a term, only RPC pair production, mostly  +   and    2 0, with (cascade) decays to LSP’s followed by RPV decays  e e-e-  ~  0101 ~ 121 e.g.  4 charged leptons + missing-E T With a ’ i11 term, also resonant production: e.g.

J.-F. GrivazSUSY-06 June 16, R-parity violation: ijk DØ: 121, 122, 133 considered Three trilepton searches combined: eee/  0.9  0.4 (background  /e 0.4  0.1 (events 0 candidate ee  1.3  1.8 (expected NN  -ID validated with Z  CDF also used clean four-lepton topologies: 0 candidate vs  bg. expected For 133, ee  most powerful at large tan  and low m 0 : m(  1 0 ) > 115 GeV for tan  = 20, A 0 = 0,   0 and m 0 = 100 GeV Autermann

J.-F. GrivazSUSY-06 June 16, R-parity violation: ’ ijk DØ: ’ 211 resonant production Reconstruct: m(smuon) = m(  jj) m(  1 0 ) = m(  jj) No accumulation m(smuon) > 210 to 363 GeV for ’ 211 > 0.04 to 0.10 (tan  =5, A 0 =0 and  < 0) CDF: ’ 333 pair production Look for (  e/  )(  hadrons) +2 jets 2 candidates vs. 2.3  0.5 bg. (Also LQ3) AutermannMartinez

J.-F. GrivazSUSY-06 June 16, Neutral Long Lived Particles DØ search motivated by 3 dimuon events in the NuTeV experiment Production and decay model: SUSY RPV with a small 122 Look for displaced dimuon vertices (5 to 20 cm) Calibrate with K s  decays 0 candidate vs. 0.8  1.6 bg. Convert NuTeV (p-p at 38 GeV) to DØ (p-pbar at 1.96 TeV) (383 pb -1 ) Autermann

J.-F. GrivazSUSY-06 June 16, Charged Massive Stable Particles Long-lived charginos are expected in some AMSB models with a “wino-LSP” (small   –  1 0 mass difference) They would appear in DØ as slowly-moving muons  Make use of the time information of the muon system scintillators For a 150 GeV chargino: 0 candidates for 0.69  0.05 bg. Gershtein

J.-F. GrivazSUSY-06 June 16, Gauge Mediated SUSY Breaking In GMSB, the LSP is a light gravitino G A  1 0 NLSP decays into  +G All backgrounds determined from data (fake photons from dijet events, W  e +  /jet) p T (  ) > 25 GeV Missing E T > 45 GeV 4 candidates vs. 1.8  0.7 bg. “mGMSB Snowmass slope” (N=1, M m = 2 ,   0, tan  = 15) Signal dominated by    2 0 production m(  1 0 ) > 120 GeV  Inclusive search by DØ for  + missing E T Gershtein

J.-F. GrivazSUSY-06 June 16, Stopped Gluinos In “Split-SUSY”, squarks are ultra-heavy  long-lived gluinos Such gluinos form R-hadrons which may stop in the DØ calorimeter. Backgrounds: beam and cosmic muons, measured in data. Strategy: look for a randomly oriented monojet in an otherwise empty event (diffractive trigger). After a while, they decay into a gluon +  1 0 (q-qbar-  1 0 is also possible). (A. Arvanitaki et al., arXiv:hep-ph/ ) m(  1 0 ) = 50, 90, 200 GeV Excludes gluino masses up to 300 GeV Gershtein

J.-F. GrivazSUSY-06 June 16, Indirect limits from B s  SM: B s  is heavily suppressed SUSY: large enhancement Huge dimuon background Discriminate using Decay length Isolation Pointing Normalize to B +  J/  K + Limit at 95% C.L (780 pb -1 ): BR(B s   ) < candidate event selected in a  60 MeV mass window vs. 1.4  0.4 bg. expected CDF search: Carena  GeV

J.-F. GrivazSUSY-06 June 16, Extra Dimensions

J.-F. GrivazSUSY-06 June 16, Extra-dimensions …come in many flavors: LED, TeV -1, UED, RS Two classes of models considered: ADD 2 to 7 large (sub mm) EDs gravity propagates freely in the bulk KK excitations cannot be resolved RS one 5 th (infinite) ED with warped geometry gravity is localized on a brane other than the SM KK excitations have spacings of order TeV

J.-F. GrivazSUSY-06 June 16, Large Extra Dimensions Two main search streams at the TeVatron: Real graviton emission Apparent energy-momentum non-conservation in 3D-space  “Monojets” Direct sensitivity to the fundamental Planck scale M D G KK g q q g g g V V f f f f Virtual graviton exchange Modifies SM cross sections Sensitivity to the theory cutoff M S (M S expected to be  M D )

J.-F. GrivazSUSY-06 June 16, Monojets CDF search in 1.1 fb -1 : Main selection cuts: one high pT jet (  150 GeV) (soft jets from ISR are allowed) isolated lepton veto Missing E T away from jets Missing E T  120 GeV Main background: (Z  ) +jet Calibrated with (Z  ll and W  l ) + jet QCD is negligible 779 events selected 819  71 expected Beauchemin

J.-F. GrivazSUSY-06 June 16, High p T dileptons & diphotons DØ search in 200 pb -1 combines ee and  to maximize the sensitivity Still world tightest limits: M S > 1.36 TeV M S >1.43 TeV I in the GRW formalism Fit of Data to SM+QCD+LED(M S )

J.-F. GrivazSUSY-06 June 16, Randall – Sundrum gravitons Here too, most of the sensitivity is in diphotons (BR = 2  ee) DØ combined ee +  as for the LED search  doesn’t add much Two model parameters: Mass and coupling (  /M Pl ) For  /M Pl = 0.1: M  785 GeV

J.-F. GrivazSUSY-06 June 16, Looking for the unexpected

J.-F. GrivazSUSY-06 June 16, Signature based searches  + X in 0.7 to 1 fb -1 X=e2 vs. 4.5  0.8 X=  0 vs. 0.5  0.1 X=  4 vs. 1.9  0.6 l  + Missing E T in 0.3 fb-1 l=e25 vs  3.2 l=  18 vs  2.2 (CDF Run I excess not confirmed) (Also multileptons + photon) CDF: Goncharov

J.-F. GrivazSUSY-06 June 16, Final remarks With a steadily improving collider performance there are still a number of years and fb –1 ahead of us for frontier physics at the TeVatron. CDF and DØ have now begun to explore clearly virgin territories. Already 1.3 fb -1 on tape, only partially deciphered  Expect many new results in the coming months

J.-F. GrivazSUSY-06 June 16, Back-up Slides

J.-F. GrivazSUSY-06 June 16,

J.-F. GrivazSUSY-06 June 16,

J.-F. GrivazSUSY-06 June 16, (tree level) (loop) Stop decays in mSUGRA m 0 = 200 to 600 GeV (50 GeV step) m ½ = 110 to 180 GeV (10 GeV step) A 0 = –500 to –1000 GeV (100 GeV step) tan  = 3 and 10 to 50 (10 step) Both signs of 