Tracey Pratt Durham Exotics Workshop Large Searches at CDF, Tevatron Tracey Pratt Liverpool University  Extra Dimensional models  Tevatron and the CDF detector  Run I & Run II searches  Future reaches at the Tevatron  Questions  Conclusions and outlook March 2003

Tracey Pratt Durham Exotics Workshop Extra dimensional solutions to the hierarchy problem (M EW << M Planck ?) G Many large extra dimensions (n=2-7) gravity freely propagates in the ED Taking the compact space to be very largeCurvature of the extra dimension 1 highly curved extra dimension gravity localised in the ED Scale of physical phenomena on the TeV-brane is specified by the exponential warp factor:   = M pl e -kR c    ~ TeV if kR c ~ Planck TeV brane compactified for n  2, R c < 1 mm V n = 2  R c n M Pl(4+n) ~ 1 TeV M Pl 2 = V n M Pl(4+n) (2+n)  requires R c ~ 10 (30/n –19) m To solve hierarchy choose Torus

Tracey Pratt Durham Exotics Workshop Searching for ED Two classes of experimental tests 1.Graviton emission and a photon or a jet recoiling against it, Gravitons, do not interact with the detector, and radiate into the bulk appearing as missing energy: jet + E T  + E T Cross section depends on the number of extra dimensions 2. Graviton exchange Deviations in the cross section from SM predictions New Parameters (Hewett formalism) 1.M s 2., dimensionless parameter,  1 Since gravitons can propagate in the bulk, energy and momentum are not conserved in the G KK emission from the point of view of our 3+1 space-time Since the spin 2 graviton in generally a has a bulk momentum component, its spin from the point of view of our brane can appear as 0, 1 or 2 Gravitons, do not interact with the detector, and radiate into the bulk, appearing as missing energy: jet + ME T  + ME T Cross section depends on the number of ED the collider signatures include single photons/Z/jets with missing E T or fermion/vector boson pair production probe Kaluza-Klein gravitons (G KK ) by: Picture of cross- section for emission Run I M  (GeV) 2) Graviton exchange: virtual contribution to the scattering processes Deviations in cross sections and asymmetries of SM processes e.g.qq-bar  l + l -,   Or new processes e.g. gg  l + l -, Cross section independent of the number of ED in Hewett formalism Gupta et. al. hep-ph/  s is the Planck scale in the extra dimensions is a dimensionless parameter of order  1 =+1 New Parameter Fundamental mass scale M D G N -1 = 8  R n M 2+n D, where G N -1 Newton’s constant New Parameter Fundamental mass scale M D and R are related to Newton’s constant G N -1 and the number of extra dimensions by G N -1 = 8  R n M 2+n D 1) Direct G KK emission in association with a vector-boson New Parameter M D = M Pl(4+n)

Tracey Pratt Durham Exotics Workshop Searching for ED (Add BRs here?!) (Why not diphoton ?!!) K/M Pl GeV KK Graviton at the Tevatron k/M Pl = 1,0.7,0.5,0.3,0.2,0.1 from top to bottom M ll (GeV) RS model Dilepton channel M ll (GeV) – Tevatron 700 GeV KK graviton d  /dM (pb/GeV) couplings of each individual KK excitation are determined by the scale,   = M pl e -kR c  ~ TeV. masses m n = kx n e -kr c  (J 1 (x n )=0) Massive eigenstates only suppressed by   -1 ~ TeV -1 RS modes can be excited individually on resonance Via Virtual exchange but different expected cross sections/distributions from ADD model Via virtual exchange Davoudiasl, Hewett, Rizzo hep-ph GeV KK Graviton at the Tevatron k/M Pl = 1,0.7,0.5,0.3,0.2,0.1 from top to bottom M ll (GeV) RS model Dilepton channel M ll (GeV) – Tevatron 700 GeV graviton LHC 1500 GeV graviton d  /dM (pb/GeV) KK excitations can be excited individually on resonance The cleanest signature for graviton resonance production is an excess of events in the dilepton or dijet channel GeV G KK and subsequent tower states K/M Pl New parameters: 1.First graviton excitation mass: m 1 2.A ratio: k/ M pl   = m 1 M pl /kx 1,,  1 =  m 1 x 1 2 ( k/ M pl ) 2 LHC

Tracey Pratt Durham Exotics Workshop CDF Run I ( ) L ~ 110 pb -1  s  1.8 TeV Run II ( ) L ~ 2000 pb -1  s  2 TeV Tevatron pp collider Highest energy collider operating in the world! D0 p 980 GeV/c 2  s  2 TeV uu d p uu d 20 x more events Physics reach extended 8 and ability to set improved limits on new physics

Tracey Pratt Durham Exotics Workshop CDF at the Tevatron CDF detector is essentially new, commissioned and now taking physics-quality data! Improved sensitivity for leptons and photons Highlights of Upgrade Improved trigger Improved silicon tracker Improved central outer tracker New forward calorimeters Extended muon coverage Time of flight detector EM calorimeter timing (Summer 03) Run IRun II Taking physics quality data since February 2002 Muon System COT Plug Calorimeter Time-of-Flight Central Calorimeters Solenoid Silicon Tracker

Tracey Pratt Durham Exotics Workshop CDF ED Searches Emission Channels  + ME T, jet+ ME T Exchange Diphoton, Dielectron and combined Dimuon Dielectron and combined (Diphoton) (Dijet) (top pair, Run I Run II

Tracey Pratt Durham Exotics Workshop Run I G KK emission:  E t CDF 5725 Limits n=4 M D > 0.55 TeV n=6 M D > 0.58 TeV n=8 M D > 0.60 TeV The fundamental mass scale M D and R are related to Newton’s constant G N -1 and the number of extra dimensions by G N -1 = 8  R n M 2+n D No signal is observed L3 has set limit M S >1 TeV for n=2 (hep-ph ) qq   G KK Search Selection - One  with E T > 55 GeV and |  |<1 - Missing E T > 45 GeV - No jets with E T > 15 GeV - No tracks with p T > 5 GeV Main backgrounds Cosmic rays where muon undergoes a Bremsstrahlung in the calorimeter Irreducible Z   +  W  e (  ), W  (  ),  (  ),jet-jet,  -jet (  +MEt) Results Expected background: 11.0  2.3 Observed: 11 irreducible 95 % C.L. ADD limits: G N -1 = 8  R n M 2+n D M D = 549, 581, 602 GeV n=4,6,8 extra dimensions but no track is found Corrected photon E T Events per 5 GeV Other backgrounds: W->e nu, where the e is misidentified as a photon W  -> where the charged lepton in a leptonic W decay is lost Prompt photon-photon production where a photon is lost Dijet Photon+jet production CR cuts are timing cuts (No jets with E T > 15 GeV and No tracks with p T > 5 GeV) are to remove backgds from W  and events in which mismeasurement of jet energy produces fake MEt Events surviving cuts 15,046 1, PRD Cosmic ray muons 6.3  2.0 Z 0  +  3.2  1.0 W  e ( “  “ )0.9  0.1 Prompt diphotons 0.4  0.1 W ()W () 0.3  0.1 Main backgrounds 87 pb -1 Numbers don’t add due to rounding

Tracey Pratt Durham Exotics Workshop EM calorimeter timing Expected number of events with timing 22 GeV 55 GeV EM Calorimeters Hadronic Reducing the kinematic requirement would increase the signal by a factor of 2.8 And decrease cosmic ray background

Tracey Pratt Durham Exotics Workshop Real G KK emission : jets+E t CDF 5151 Dashed lines for  from Pythia Solid lines prediction from Giudice, Rattazi and Wells (hep-ph ) from Pythia prediction from Giudice, Rattazi and Wells (hep-ph )  falls as 1/M D n+2 for all subprocesses qq-bar  gG is larger for larger values of n, relative to the other sub- processes, since  (gg  gG) and  (qg  gG) depend on (m 2 /s) 4 Whereas  (qq-bar  gG) depends on (m 2 /s) 3 This results in larger splittings at high values of M D between values of n for qg and gg  gG compared to qq-bar  gG. For n=2 qq-bar is not the dominate process, but for n>2 then this is the dominate process Process M D = 1 TeV  n  (pb)  Total)  n   (pb)  Total)  n  (pb)  Total) qq-bar  gG KK 4.1 (0.16) 1.6 (0.53) 0.70 (0.78) qg  gG KK 9.6 (0.38) 0.68 (0.22) (0.11) qg  gG KK 11.4 (0.45) 0.77 (0.25) 0.11 (0.12) Total Tevatron  s=2 TeV M D = 1.2 TeV n=4 n=2 p T min (GeV) gg  gG KK qg  gG KK qq  gG KK dominate sub-process for n>2 q qqqqq q q q g g gg G KK g g g g g gg g g g g q qqq qq q ggg g q q g

Tracey Pratt Durham Exotics Workshop CDF 5151 The fundamental mass scale M D and R are related to Newton’s constant G N -1 and the number of extra dimensions by G N -1 = 8  R n M 2+n D Compare to LEP and Delphi results?- in the paper (for that time) Search Selection Jet E T 1st  80 GeV, |  | 80 GeV a second jet is allowed if E T 2nd > 30 GeV no isolated tracks in event (p T  10 GeV) Main background Z(  )+jets, W(   ) +jets. L3 gives limit M s > 600 GeV hepph pp  jet +ME t subprocesses: qg  gG, qq-bar  gG and gg  gG. Main bkgd from Z+jet  +jet LHC: qg  gG gives largest contribution M D (GeV) > nCDF(K=1.0)D0(K=1.0)D0(K=1.34) Best limits from the Tevatron from searches for direct graviton emission Run Ib G KK emission: jets+E T Results Expected: 274  16 Observed: 284 events. Relative uncertainty on the signal acceptance 25 % Limits 95 % C.L. upper limit on number of signal events:  4 pb -1 Used Poilim (poisson statistics)  Normalise bkgd predictions to Zee+jets data and use direct normalisation of W- >enu+jets as a cross check Allowing a 2 nd jet: improves the signal eff. (2 nd jet from ISR or FSR) And allows us to estimate the QCD bkgd using data. No tracks; reduces bkgd from W+jets

Tracey Pratt Durham Exotics Workshop Predicted results for G KK emission  jet+E T nCDF Run I results (GeV) M D reach Run I (GeV) M D reach Run II >300pb -1 (GeV) M D reach LHC 100 fb -1 (TeV) hep-ph (1999) Bounds obtained by requiring Tevatron:  signal >205 fb (for  s=2 TeV) with the acceptance cuts |  jet |<3 and E min T, jet = 150 GeV. LHC:  signal >2.6 fb (for  s=14 TeV) with the acceptance cuts |  jet |<3 and E min T, jet = 1 TeV. and requiring signal significance S/  B = 5, assuming bkgd cross-section known to within 10 % and requiring that the signal be more than 50 % of the background to have confidence of a discovery. PRL 82,2236 (1999) G. Giudice, R. Rattazzi, J. Wells |  jet |<1.1 and E min T, jet = 80 GeV LHC with 300 times more data

Tracey Pratt Durham Exotics Workshop Virtual Graviton Exchange Clean experimental signature. Low backgrounds  /Z 0 l-l- q q ++ q q g g l+l+ l-l- l+l+ l+l+ l-l- KK n Diphoton Channel gg initiated process + KK n + q q Interference term of gg-> between SM and KK is not in their gamgam searches in Run I, they take this a a systematic uncert, however, interference of qq-bar term is in the MC and gg interference term about 0.1* qq-bar interference term (CDF5694) Dilepton Channel qq-bar and gg ->  : gg process contributes about 30 % of the cross-section Extra Dimensions Standard Model + + +

Tracey Pratt Durham Exotics Workshop Fit method used (Comment on ang distrib too )  s is the Planck scale in the extra dimensions is a dimensionless parameter of order  1 CDF 5892,5373 K LED =1.3 and to date (March 2002) has not been theoretically estimated. A 3 parameter (n SM, n BG,  ) unbinned likelihood function is used to extract  Generate MC templates for each piece independent of the choice of and  s 4. K LED applies to the LED terms of the cross section, to estimate the effect of non-leading orders in LED. No estimate of K LED ; so results quoted for K LED =1.0 (no correction) and 1.3 (SM-like) K LED M  (GeV/c 2 ) events Parameterise the cross section in terms of  = /  s 4  =  SM +  INT +  2  KK  BG A different choice of and  s 4 would affect the templates’ relative and absolute normalisations, but not their shapes. Shapes depend only on the general structure of the lagrangian and on the pdfs.

Tracey Pratt Durham Exotics Workshop CDF  Run I search for LED Search Selection 2  with E t > 22 GeV, CC or CP: central (|  | < 1), plug (1<|  | <2.4) Main backgrounds: fakes from  -jet and jet-jet Results Observed: 287 Central Central events 192 Central Plug events Limits Using a maximum likelihood fit method CDF: M  > 150 GeV 5 events are observed where 4.5 +/-0.6 were expected with luminosity 100 pb -1, and a limit M S > 0.9 TeV for n=4 was obtained. (hepph ) CDF5694 MC distribution for the excluded signal shown here too CC 100 pb -1, CP 87 pb -1   Plug Central 2 separate analyses – CP and CC – then combined to give: Problems gg interference – 95 % C.L. M S > 899 / 797 GeV K LED = 1.0 ( = -1/+1, Hewett) M  highest = 288 GeV/c 2 Background falls off faster than signal. In CC above 200 GeV: Expect less than 0.2 events, as opposed to 2.5 SM  events  

Tracey Pratt Durham Exotics Workshop CDF Run I ee search for LED 2 high E t isolated electrons (> 25 GeV) (CC and CP) ee and  CDF results cdf % C.L. M S > 826 / 905 GeV ( = +1/-1, Hewett) K LED = % C.L. M S > 853 / 939 GeV ( = +1/-1, Hewett) K LED = 1.3 K LED applies to the LED terms of the cross section, and to date (March 2002) has not been theoretically estimated. Therefore quote a SM- like K-factor result and also one where no loop corrections are assumed. 95 % C.L. M S > 780 / 768 GeV ( = -1/+1, Hewett) K LED = % C.L. M S > 826 / 808 GeV ( = -1/+1, Hewett) K LED = separate analyses – CP and CC – then combined to give: Highest energy event is 500 GeV 110  7 pb -1 N SM CP = 3883  292 (DY) N BG CP = 224  71 Observed 3825 Main Backgrounds: Drell-Yan, QCD di-jet, diboson production, Z ,tt-bar production CDF 5892 N SM CC = 3463  223 (DY) 500 GeV CC: 3319CP: 3825

Tracey Pratt Durham Exotics Workshop CDF  + ee search for LED Combine the likelihoods (cdf5753) (Acounting for correlated and uncorrelated uncertainties) Channel95 % C.L. M S (Hewett) K LED = 1.0K LED = 1.3 = -1 = +1 = -1 = +1 ee  ee and  Diphoton channel is more sensitive to LED than dielectrons, because the LED production cross-section is higher The LED dielectron analysis has a 500 GeV ee event which is more consistent with LED than the SM. CDF5753 CDF found that a 2 dimension fit in both invariant mass and angular distribution only gave a slight improvement over the 1-dimensional fit in their statistically limited samples. as advocated by Cheung and Landsberg)hep-ph/ (D0 does not include the gg  process, which cdf found increases the SM cross section by about 30 %) cdf 5373

Tracey Pratt Durham Exotics Workshop Run II G KK exchange reaches 2 fb -1 Run II dilepton data (hep-ph ) Increased sensitivity to ADD model since can study angular distribution with more statistics Compare to LEP? Add Z’ table numbers ADD model Run I (110 pb -1 ) ee +  M s TeV for n=7-2 corresponds to R < 0.3 mm (n-2) and R < 2 fm (n=7) Run II (2 fb -1 ) M s TeV for n=7-2 n = number of extra dimensions HLZ notation: hep-ex D0 results: ADD Corresponds to R < 0.3 mm (n-2) and R < 2 fm (n=7) D0 Collab. hep-ex Run I, 0.13 fb -1 2 fb fb -1 LHC, 100 fb TeV1.9 TeV2.6 TeV9.9 TeV 95 % C.L. sensitivity limits on M s (n=4), from , ee,  channels Using double differential cross-sections n=7-2 extra dimensions Tevatron Cheung hep-ph Run I, 0.13 fb -1 Run IIa, 2 fb -1 Run IIb, 20 fb -1 LHC, 100 fb fb TeV % C.L. sensitivity limits on M s (HLZ) n=4 e + e - +  +  - +  Using double differential cross-sections HLZ formalism: sign of interference fixed, interference term is ~ F / M S 4, where F reflects the number of ED F = log(M S 2 /2), n=2 F = 2/(n-2), n>2  =  F. M S 4 (Hewett) 2 M S 4 (HLZ) Han, Lykken and Zhang Phys Rev D 59, (1999) 2 fb fb -1

Tracey Pratt Durham Exotics Workshop CDF ED Searches Emission Channels  + ME T, jet+ ME T Exchange Diphoton, Dielectron and combined Dimuon Dielectron and combined (Diphoton) (Dijet) (top pair, Run I Run II

Tracey Pratt Durham Exotics Workshop Initial Run II limits: ee,  M Z‘ > 275 GeV/c 2 16 pb -1 No deviations from the SM observed Limits set on one Z’ and RS model 0.1 K/M Pl L = 16 pb % C.L. Excluded Region Run 2  Graviton mass (GeV/c 2 )  pb Dimuon mass (GeV/c 2 ) Events / 5 GeV CDF6080,6073 ICHEP 2002

Tracey Pratt Durham Exotics Workshop limits  72 pb  55  00 42  Search selection 2 isolated  P T >20 GeV/c, |  |<1 Cosmic ray rejection cuts Results Observed 775 events Signal region above 150 GeV/c 2 observed 4 events Limits 95 % C.L. upper limit on number of signal events: 5.6 K= GeV/c 2 CDF6344

Tracey Pratt Durham Exotics Workshop Run II cosmic ray rejection using the Time-of-Flight detector Remove cosmic rays with a cut requiring T upper – T lower > -5 ns T upper – T lower ~ 2L/c for cosmic ray dimuons ~ 0 for interaction dimuons Time resolution  100 ps Cosmic ray muonsInteraction muons r z T upper T lower

Tracey Pratt Durham Exotics Workshop Run II ee search 72 pb GeV Search selection 2 isolated e (CC, CP) E T >25 GeV Results Observed: 4576 ee events Above 200 GeV/c 2 observed 27, expected 16  8 Above 350 GeV/c 2 observed 3, expected 1.1  0.3 CDF6343

Tracey Pratt Durham Exotics Workshop ee better limits than in  channel, because plug gives e a larger acceptance and a higher efficiency per event Run II ee search 72 pb -1 3 ,e 00 42 ,  20 % rather than 50% Total acceptance Effic: for ee CC:84% CP:69% Mm: PP= 57%, XX 65%, PX 61% CDF % C.L. Excluded region K=1.3

Tracey Pratt Durham Exotics Workshop Run II ee +  search 72 pb % C.L. Excluded region K=1.3

Tracey Pratt Durham Exotics Workshop CDF model searches  Future: Add more of the  detector acceptance Use Run II dijet and diphoton searches to set RS limits 25  55  00 42  |  |<0.6 |  |<1 |  |<1.5

Tracey Pratt Durham Exotics Workshop Run II dijet search at CDF Inclusive Jet samples 2 highest E T jets selected Fit of the mass spectrum with a simple background parameterisation and search for bumps comparable with mass resolution No significant evidence for a new particle RS model dijet limits to be determined. Highest mass event 1364 GeV/c 2 E T =666 GeV (corr) 583 GeV (raw)  =0.31 (detector) =0.43 (correct z) E T =633 GeV (corr) 546 GeV (raw)  =-0.30 (detector) =-0.19 (correct z) z vertex = - 25 cm J1 E T = 666 GeV (corr) 583 GeV (raw) J1  = 0.31 (detector) = 0.43 (correct z) J2 E T = 633 GeV (corr) 546 GeV (raw) J2  = (detector) = (correct z) z  CDF6248 MET/  E T <6 and  E<2.2 TeV

Tracey Pratt Durham Exotics Workshop Run II diphoton search Results Highest mass event is: 168 GeV/c 2 Above 150 GeV/c 2: Observed 2 events Expected 3.3 events Search selection Isolated  with E T > 13 GeV, |  | < 0.9 No 3D tracks pointing to em cluster Bins are 20 % of mass 71% from jets (loose cuts) + 29% from MC No excess observed at high invariant mass Main backgrounds fakes from  -jet and jet-jet, where jet fragments into a hard  0 CDF6312

Tracey Pratt Durham Exotics Workshop Davoudiasl, Hewett, Rizzo hep-ph constraints m 1 (GeV) K/M Pl Tevatron 110 pb -1 Dijet and dilepton data Oblique Parameters   < 10 TeV Solve hierarchy |R 5 | < M 5 2 Curvature of 5 th dimension LHC 10 fb -1 Dilepton data Allowed Region 2 fb -1 Sridhar hep-ph m 1 : GeV Diphoton data 2 fb -1

Tracey Pratt Durham Exotics Workshop Outstanding Questions K factor: ADD CDF ee+  use K LED = 1.0 and 1.3 “They place a K LED on the LED terms of the production cross-section: 1.0 for no loop corrections and a SM-like 1.3 for two independent cases.” (cdf 5753) used to correct the LO cross-section to NLO: ?? Should K=1.3 apply to the non- QCD process of graviton exchange? K LED applies to the LED terms of the cross section, to estimate the effect of non-leading orders in LED. CDF 5373 No interference between the gg SM and KK terms included in their Pythia input - this has been included into the systematics This inference is relatively small compared to the direct KK terms, and has quite a complex analytic form. Has been computed by Eboli et al (hep-ph/ ) qg-> gam gam is about 30 % of the cross section of qq-bar - > gam gam  Is ADD model graviton exchange in Pythia ? MC program by Ulrich Baur, but no interference between the SM gg box diagrams and the tree-level gg graph Has been calculated by Eboli et al (hep-ph/ ) Included as a systematic uncertainty (  Sys INT ) at present (  Sys INT = 34 %  Sys Total for  =-1, 43 % for =+1) ( including K=1.3 increases sensitivity by about 30 GeV in exchange processes ) 1.0 as for no loop corrections ? or 1.3 like in the SM ? Justified? Not clear, since the NLO processes including gravitons are quite different than the SM NLO QCD processes  =  SM + K LED (   INT +  2  KK )  What should the k-factor used for ED searches Not clear, since the NLO processes including gravitons are quite different than the QCD processes (e.g. gg box diagram) that enhance SM photon production. Reasonable to multiply the  qq by 1.3, but also for interference (  INT ) and direct signal (  KK ) processes? Interference term of gg-> between SM and KK is not in their gamgam searches in Run I, they take this a a systematic uncert, however, interference of qq-bar term is in the MC and gg interference term about 0.1* qq-bar interference term (CDF5694) Get Syst Uncert by varying the qq-bar interference cross-section by +/-100 %,this is an over estimate. cdf5658

Tracey Pratt Durham Exotics Workshop Conclusions and outlook  Searches performed in several channels at CDF  No evidence of deviations from Standard Model expectation observed  Best limits obtained ADD jets+E T, ee +  ~ 1 TeV RS ee +  m 1 ~ 365 to 550 GeV for k/M Pl 0.05 to 0.1  Tevatron Run II has successfully started, the first CDF Run II results already determined and.. to be updated in the future…  Tevatron Run IIa (2 fb -1 ) has a promising observation potential and should be in a position to discover ED, if they exist, ADD: up to about M S = 2 TeV RS: m 1 from 0.5 to 1 TeV for k/M Pl 0.01 to 0.1  The highest limits obtained are from the ** channel.  Many interesting channels to look in.  Run II results already coming in  To be updated in the future… ADD ee +  939 (853) GeV for =-1 (+1), K LED = 1.3 ADD jets+E T 995 for n=2, 768 for n=4 RS ee 205 to 535 GeV for k/M Pl to 0.1  Tevatron Run II has a promising observation potential and should be in a position to discover ED, if they exist, ADD: up to about M S = 2 to 3 TeV (Runs IIa, 2 fb -1 ; IIb, 20 fb -1 ) RS: m 1 from 0.5 to 1 TeV for k/M Pl 0.01 to 0.1 (Run IIa, 2 fb -1 )

Tracey Pratt Durham Exotics Workshop THE END!

Tracey Pratt Durham Exotics Workshop Jets+MEt Process M D = 1 TeV  n  (pb)  Total)  n   (pb)  Total)  n  (pb)  Total) qq-bar  gG KK 4.1 (0.16) 1.6 (0.53) 0.70 (0.78) qg  gG KK 9.6 (0.38) 0.68 (0.22) (0.11) qg  gG KK 11.4 (0.45) 0.77 (0.25) 0.11 (0.12) Total cdf5151

Tracey Pratt Durham Exotics Workshop CDF ll/  LED search method ee and  CDF results cdf % C.L. M S > 826 / 905 GeV ( = +1/-1, Hewett) K LED = % C.L. M S > 853 / 939 GeV ( = +1/-1, Hewett) K LED = pb -1 +/- 7 Run I N SM CC = 3463  223 N SM CP = 3883  292 N BG CP = 224  71 The CC BG is negligible. Observed: CC: 3319, CP: ) Scan through , and at each point, reminimise L w.r.t n SM and n BG. 2) Plot L 3) 95 % C.L. result is the value of  such that 95 % of area under the likelihood function lies between it and 0. L = 1 e – ADD Equation! Page 15 cdf 5892  2  SM 2 n LED (  ) is the fitted number of events attributable to LED physics 3 parameter unbinned likelihood function: n SM, n BG  = /M S 4 Bayesian gaussian prior on n SM events Bayesian gaussian prior on n BG events Poisson constraint on total number of events Term to weight events according to its consistency with the SM, SM-LED interference, direct KK shapes, and BG shapes CDF 5892,5373

Tracey Pratt Durham Exotics Workshop Tevatron

Tracey Pratt Durham Exotics Workshop Dimuon acceptance

Tracey Pratt Durham Exotics Workshop Diphoton constraints hep-ph Diphoton production at Tevatron Run II sensitive to mass of first KK graviton resonance (m 1 ) : GeV ADD K factor for both and ref and add bin sizes And know method – xhi Squ !? LHC: can probe first graviton excitation up to ~ TeV For K/M Pl 0.01 to % C.L. m 0 Tevatron: GeV implies mass of first KK graviton resonance must lie above 700 GeV m 0 (GeV) K/M Pl  s = 2 TeV L = 2fb -1 Run II a, b 95 % C.L. m 0 (GeV) K/M Pl  s = 14 TeV L = 100fb % C.L. m 1 : GeV m 1 : TeV TevatronLHC |   |<1.2 for both  |   |<2.5 for both  Using (K LED =1.3) for full 