e + e - H1 Highlights for EPS03 High Q 2 Cross Sections and PDFs QCD Tests with jets and heavy flavours Low x Physics Searches for new Physics

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1 Multi electron Event M()=3 GeV H Highlights for EPS3 PT=63 GeV Paul Newman Birmingham University PT=6 GeV High Q Cross Sections and PDFs QCD Tests with jets and heavy flavours Low x Physics Searches for new Physics intergrated luminosity (/pb) 5 HERA luminosity e E P = 9 GeV E P = 8 GeV e H 5 days of running

2 Results to Be Shown for the First Time at a Major Conference Final high Q NC & CC xsecs / pdfs New method and data on F L at low Q F from QED-Comptons F D at high Q γp γy at high t Deeply-Virtual Compton Scattering NLO Treatment of Diffractive Final States Elastic J/ψ photoproduction High t J/ψ D photoproduction D (+ jet) in DIS will not appear b µ Photoproduction, 3-jet event shapes at high Q Dijets at low x Prompt Photons with Associated Jets Inclusive η, ρ, f, f photoproduction General Search for new Phenomena R-parity Violating SUSY (full data) Search for Superlight Gravitino Search for magnetic monopoles Multi Electron Production Contact Interactions 53 papers submitted to conference, summarising work of last years

3 High Q NC & CC Cross Sections and Fits F i x =.5, i = x =.8, i = x =.3, i = 9 H PDF extrapolation x =., i = 8 x =.3, i = 7 x =.5, i = 6 x =.8, i = 5 x =.3, i = 4 x =., i = 3 x =.3, i = x =.5, i = x =.8, i = x =.3, i = 9 x =., i = 8 x =.3, i = 7 x =.5, i = 6 H e + p high Q 94- H e + p low Q BCDMS NMC x =.8, i = 5 x =.3, i = 4 x =.8, i = 3 x =.5, i = x =.4, i = x =.65, i = Q / GeV H Collaboration xp(x) xd xu xu v xd v xg x xu xd H PDF : Q = 4 GeV Fit to H data experimental errors model uncertainties Fit to H + BCDMS data parton distribution Beautiful summary of years of high Q inclusive measurements Parton densities from H data alone! U = u + c etc x H Collaboration

4 NC Comparison between H and ZEUS F i x =.5, i = x =.8, i = x =.3, i = 9 x =., i = 8 x =.3, i = 7 x =.5, i = 6 x =.8, i = 5 x =.3, i = 4 x =., i = 3 x =.3, i = H e + p ZEUS e + p BCDMS NMC xf(x,q ) xu Q = GeV H PDF ZEUS-S PDF xu xf(x,q ) Q = GeV xu H PDF ZEUS-S PDF xu 3 x =.5, i = x =.8, i = x =.3, i = 9 x =., i = 8 x =.3, i = 7.5 xd xd.5 xd xd - - H PDF extrapolation -3 x =.5, i = 6 x =.8, i = 5 x =.3, i = 4 x =.8, i = 3 x =.5, i = x =.4, i = x =.65, i = Q / GeV H Collaboration 5 xg x 5 xg Consistency between experiments in data Reasonable consistency in pdf s x

5 Search for Contact Interactions dσ/dq / dσ SM /dq 3 e p NC data s =39 GeV 3 4 dσ/dq / dσ SM /dq 3 e + p NC data s =39 GeV 3 4 H Λ (TeV) Λ + (TeV) LL.6.8 LR RL. 3.3 RR..8 VV AA 4..5 VA 3..9 LL+RR RL+LR H 3 4 Q (GeV ) H 3 4 Q (GeV ) 5 5 ελ (TeV) H NC data consistent with Standard Model (CTEQ partons) up to highest Q Competitive limits on compositeness scales, LQ, SUSY, large extra dimensions Quark radius constrained to R q < 8 m

6 Differential -jet and 3-jet Event Shapes at high Q New differential measurements in extended Q range dσ/dτ /σ 3 H preliminary )+NLL+PC NLO( α s jet shapes: τ B τ C C ρ 3 jet shapes: K out /Q χ Jet rates: y kt y3 kt y4 kt - jet shapes: Fits using NLO QCD new - resummed calculations power corrections e.g. τ = Thrust -3-4 <Q>= 5 GeV <Q>= 8 GeV <Q>= 4 GeV <Q>= 37 GeV <Q>= 58 GeV <Q>= 8 GeV <Q>=6 GeV..5. τ

7 Impact of New Measurements 95- data, resummed, fit distributions data, non-resummed, fit means α (µ I = GeV).6.55 τ c H preliminary B C )+NLL+PC Fits NLO( α s stat. and exp. syst. errors Q >GeV α _ (µ Ι = GeV).7.6 Power Correction Fits (stat. and exp. syst. uncertainties) ρ ρ τ world average...3 α s (m Z ) More consistent picture results for α s and H B τ τ c C α s (M Z ) power correction parameter α

8 e e' D Photoproduction γ ( ) D data in tagged γp... Testing MC models and NLO theory p g [nb] dσ(ep D* X)/dη 4.5 H 99- (prel.) 4 NLO QCD: 3-flavour massive flavour massless [nb/gev] dσ(ep D* X)/dpt - - H 99- (prel.) NLO QCD: 3-flavour massive FONLL ( matched ) η (D*) pt (D*) [GeV] Not fully described by MC models or massive theory Massless, Matched FONLL better? Important data to constrain large theory uncertainties

9 D + Dijets in DIS dσ(ep ed*jjx)/de max t [nb GeV - ] H preliminary H D*+jj (prelim.) RAPGAP dir RAPGAP dir+res CASCADE E max t [GeV] σ(d * jjx) [nb] H preliminary H D * CASCADE ε=. CASCADE ε=.78 CASCADE ε=.35 RAPGAP dir.+res. RAPGAP dir. HERWIG AROMA σ(d * X) [nb] DIS Results for Inclusive D and D + dijets New insights with jet requirements LO MC models describe inclusive data well, but dijets bring sensitivity to extra effects

10 σ(ep eb bx ejjµx) in γp H Preliminary H Preliminary Events H Data (Prel.) Pythia bb Pythia cc Pythia uds Sum Events H Data (Prel.) Pythia bb Pythia cc Pythia uds Sum Impact Parameter δ [ cm ] 3 p rel t [ GeV ] Measure b cross sections for dijet events with muon associated with one jet Two observables to separate b, c and background Simultaneous D fit ) Track impact parameter δ from Silicon ) p rel (µ jet) T

11 Beauty Photoproduction Cross Sections dσ/dη µ [pb] 6 dσ/dη µ (ep ebb X ejjµx) Q < GeV. < y <.8 p µ t >.5 GeV p jet t > 7(6) GeV η jet <.5 H Data ZEUS Data NLO QCD Had dσ/dp µ t [pb/gev] dσ/dp µ t (ep ebb X ejjµx) Data H Preliminary NLO QCD Had NLO QCD 4 Q < GeV ;. < y <.8 p jet t > 7(6) GeV; η jet < < η µ < η µ p µ t [GeV] H and ZEUS in good agreement Comparisons with NLO QCD (fixed order massive) σ(ep eb bx ejjµx) : Data / NLO.8 (.5σ) for measured range Discrepancy increases as p T decreases...

12 Dijet Production at Low x γ x x g Q Jet s^ Jet Jet φ <α π Jet Azimuthal decorrelation between jets in γ p CMS sensitive to higher order effects, incoming k T Measure S = Pr ( leading jets have φ < ) Mostly well described by NLO 3-jet theory Still missing contributions at lowest x, Q!...

13 Determination of F L at Low Q F L is the ideal observable to study the low x gluon F L at low Q (MRST) - huge changes from LO, NLO, (NNLO) H Collaboration F L (x,q ) Q = GeV NNLO (average) NNLO (extremes) NLO LO Sensitivity at highest y (E e > 3 GeV) New data at lowest Q from SV run. New method introduced: Fit σ r at fixed Q : σ r = c x λ y /Y + F L

14 F L at Low Q But models that can get the Q dependence right can still be wrong No substitute for measuring x dependence... H Collaboration H F L determination now spans 3 orders of magnitude in Q Distinguishes between models!

15 QCD Hard Scattering Factorisation for Semi-Inclusive DIS Hard scattering factorisation established for diffractive DIS Diffractive parton densities extracted from H diffractive data with 6.5 < Q < 9 GeV β z Σ(z,Q ).. Singlet H σ r D NLO QCD Fit z g(z,q ) H preliminary Gluon Q [GeV ] 6.5 γ q q g (z) IP (-z) p p Test partons at higher Q and in final state data z H σ r D NLO QCD Fit (exp. error) (exp.+theor. error) H σ r D LO QCD Fit z 5 9

16 x IP σ r D(3) H 99 ( s=39 GeV, prel.) H 99- ( s=39 GeV, prel.) H 97 ( s=3 GeV, prel.) H preliminary H σ r D NLO QCD fit (prel.) extrapol. fit β=. β=.4 β=. β=. β=.4 β=.65 β=.9 Q [GeV ] x IP σ r D(3).5.5 Diffractive DIS at High Q x IP =.3 x=.3, β=.7 x=.5, β=.67 H preliminary x=.5, β=.667 x=.8, β=.667 H F D data now cover 4 orders of magnitude in Q x=.8, β=.67 x=.3, β=.433 x=., β=.667 x=.3, β=.67 3 Q [GeV ] x=.3, β=.4333 x=., β= Q [GeV ] H 97 ( s=3 GeV, prel.) H 99- ( s=39 GeV, prel.) H σ r D NLO QCD fit ( s=39 GeV, prel.) IP only extrapol. fit QCD fit to medium Q data for diffractive parton densities describes data well. new x IP

17 NLO treatment of diffractive final states γ q Calculations for previous H data using diffractive DISENT and HVQDIS. g (z) q [pb] dσ / dz IP (jets) 6 4 H Diffractive Dijets (prel.) H fit, µ r =p T, µ f =4 GeV H Data p T,() >5(4) GeV DDISENT NLO *(+δ had. ) DDISENT NLO DDISENT LO dσ / dz IP [pb] 8 6 H Diffractive D * (prel.) H fit, µ =Q +4m c H Data DHVQDIS NLO DHVQDIS LO p IP (-z) p Description 4 beyond LO+PS z IP (jets) z IP Low scales... large scale and hadronisation uncertainties Data well described Consistent description of diffractive DIS Diffractive hard scattering factorisation works!

18 γ Diffractive J/ψ µ + µ Photoproduction Elastic J/ψ µ + µ at low t... dσ/dt (W ) α(t) H: γp J/ψp H: γp J/ψp σ γp J/ψp [nb] 5 75 H 99- J/ψ µ + µ - (prelim.) H J/ψ e + e - (BR corr.) ZEUS E4 α P (t).6.4 H 99- J/ψ µ + µ - (prelim.) ZEUS 5 E FMS (CTEQ4L, λ=4) MRT (CTEQ5M) MRT (MRST99) W [GeV].8.6 Fit: α +α t α =.±. α = (.5±.6) GeV t [GeV ] Hard energy dependence σ W.7±.8 Some shrinkage: α =.5 ±.6 GeV

19 High t Diffractive J/ψ Photoproduction dσ(γp J/ψY)/dt [nb/gev ] - Data H BFKL LL (fixed α s ) BFKL LL + NL (fixed α s ) BFKL LL + NL (running α s ) DGLAP LL α IP (t).6.4. H γp J/Ψ p (prelim.) H γp J/Ψ Y (prelim.) ZEUS γp J/Ψ p α IP (t)=. -.5 GeV - t α IP (t)=.7 +. GeV - t α IP (t)=. -. GeV - t 3 t [GeV ] - t [GeV ] Unprecedented t range for VM BFKL and DGLAP models describe most aspects of data Trajectory incompatible with low t elastic J/ψ Evidence for new low x dynamics?

20 Diffractive Photoproduction of Photons at high t e γ e γ X p Y First observation of new process Lower statistics than high t J/ψ, but no uncertainty due to VM wavefunction Data reasonably described by LL BFKL model with reasonable ᾱ s

21 Deeply Virtual Compton Scattering e p γ * e e γ p New measurement higher Q p γ * e p γ σ (γ * p γp) [nb] Leading twist NLO calculation using GPDs (Freund, McDermott) Data described with dσ/dt e bt, b = 7[.5 log(q /)] GeV parameterised from ρ data Sensitivity to choice of GPD σ (γ * p γp) [nb] W [GeV] - HERA measurements consistent Q [GeV ]

22 F at High x, but Low Q k l l l k P q = l - l - k P q = l - l - k l X X Use QED-Compton events and new models for the low W region events / pb - 5 H preliminary H QEDC 997 COMPTON + bg Backgrounds 5 5 F F.5.4 Q =.5 GeV x.5 Q = 7 GeV x F Q = GeV x H QEDC 97 prel E665 H SV prel NMC H 99 prel SLAC ZEUS BPT ALLM97 Fractal log y Σ

23 e + d λ j ~ j u L u, d χ ~ + α, g, χ β χ e q q ( ν e q q ) Search for q in R p Supersymmetry e.g. e + d ũ L... e.g. e u d R... χ + q, l + Searches for squarks in R P viol. SUSY Searches for squarks in R P viol. SUSY (b) W + q, ν l λ, j Unconstrained MSSM, j=, λ, k Unconstrained MSSM, k=, Study several leptons + jets channels No significant deviations from - - e + + d c (APV) EXCLUDED IN PART OF PARAM. SPACE EXCLUDED tan β = -3 < µ < 3 GeV 7 < M < 35 GeV M LSP > 3 GeV imposed - - EXCLUDED IN PART OF PARAM. SPACE EXCLUDED λ, (CCU) tan β = -3 < µ < 3 GeV 7 < M < 35 GeV M LSP > 3 GeV imposed expectations e + + d u (ββν) H preliminary λ, (ββν) H preliminary M squark (GeV) M squark (GeV) m q < 75 GeV excluded in large part of parameter space for λ of electromagnetic strength

24 Search for Superlight Gravitino e + d χ ẽ u j γ G m e ~ (GeV) 4 H e + p preliminary theoretically inaccessible λ, j =.5 λ j If G is LSSP, produce χ via R p t-channel exchange of ẽ. Signature γ + p miss T Then χ Gγ 8 6 λ, j =.5 λ, j =. χ not NLSP GMSB, j=, tanβ =.5, µ <, N = Limits set in GMSB scenario m x (GeV)

25 General Search for New Physics Events How compatible is H data with the Standard Model overall? j j e j µ j j ν e ν e e e µ µ µ j γ e γ ν γ γ γ j j j e j j j j ν e e j e j ν µ j ν j j γ e j γ j ν γ e j j j j j j ν j j j j e j j j j 3 H General Search 4 H Data (prelim.) SM Investigation of all multi-object final states with j, e, µ, γ, p miss T... isolated... p T > GeV... < θ < 4 3+ channels!... Compare with Standard Model up to O(α s )+PS in QCD (many MC s!) Impressive agreement for most channels

26 Differential Analysis in Σp T Novel statistical algorithm to quantify level of agreement... For each channel, scan all possible connected regions in Σp T find most significant deviation and M all to Use MC experiments to determine probability ˆP of finding a more significant excess somewhere in distribution Events and M all H Data (prelim.) SM Region µ - j - ν Σ P T (GeV) Event MUON- Most significant effect from Σp T scan for µjν events... Corresponds to already reported isolated leptons with missing p T channel GeV GeV GeV H

27 Overall Compatibility with Standard Model Probability of isolated lepton excess at high p T was estimated at 3 Probability that one of the 3 studied channels would give a more significant excess in Σp T % For M all analysis, 5% probability for larger excess... Analysis confirms existing excess No new deviations found Number of Event Classes Number of Event Classes H Data (prelim.) H General Search -- results Σ P T MC Experiments µ - j - ν H General Search -- M all results H Data (prelim.) MC Experiments µ - j - ν -log P log P

28 Summary Many new H results for EPS3 - HERA-I analysis still going strong! Final HERA-I results in many areas Old topics revisited with improved precision Extended kinematic range Several new and completely original topics Significant contributions to several areas of our field Competitive sensitivity to new physics Improved parton densities and tests of QCD Unique constraints on low x Physics Thanks and Congratulations to all in H who worked on the new data!