CDF RESULTS ON DIFFRACTION AND EXCLUSIVE PRODUCTION Konstantin Goulianos 14th Workshop on Elastic and Diffractive Scattering (EDS Blois Workshop) Frontiers of QCD:  From Puzzles to Discoveries December 15-21, 2011, Qui Nhon, Vietnam

CDF Diffraction and Exclusive Production CONTENTS INTRODUCTION DIFFRACTION Diffractive W and Z production – published Diffractive structure function in dijet production – update Rapidity gaps between jets - update EXCLUSIVE PRODUCTION Exclusive gg in pp collisions at 1.96 TeV – new! CONCLUSION EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Diffraction at CDF in Run I Find PRL/PRD references in http://physics.rockefeller.edu/publications.html sT=Im fel (t=0) Elastic scattering Total cross section gap OPTICAL THEOREM f f h h SDD SD DD DPE /CD Single Diffraction or Single Dissociation Double Diffraction or Double Dissociation Double Pom. Exchange or Central Dissociation Single + Double Diffraction (SDD) multi-gap w/ two gaps  part of SD EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production Definitions p’ M x,t p p’ p p M p’ dN/dh gap particles Dh=-lnx Dh=-lnx h ln M2 ln s No radiation  no price paid for increasing diffractive gap size EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Highlights of Run I Results The MBR (Minimum Bias Rockefeller) Monte Carlo was used in the forward physics program - see: http://physics.rockefeller.edu/publications.html EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production TOTAL SD x-SECTION Run I M x,t p p’  suppressed relative to Regge KG, PLB 358, 379 (1995) 1800 GeV 540 GeV Regge Factor of ~8 (~5) suppression at √s = 1800 (540) GeV  RENORMALIZATION  CDF results √s=22 GeV EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production DD at CDF Run I gap probability x-section renormalized EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production SDD at CDF Run I Excellent agreement between data and MBR (MinBiasRockefeller) MC EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production DPE / CD at CDF Run I Excellent agreement between data and MBR  low and high masses are correctly implemented EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production Hard diffraction Run I Fraction: SD/ND ratio @ 1800 GeV Fraction % JJ 0.75 +/- 0.10 W 1.15 +/- 0.55 b 0.62 +/- 0.25 hard dN/dh J/y 1.45 +/- 0.25 All fractions ~ 1% (differences due to kinematics) ~ FACTORIZATION ! FACTORIZATION ! h EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Diffrr. Structure Function - DSF Run I  breakdown of QCD factorization Run I PRL 84, 5043 (2000) p+pp+[JJ+X] _ suppression factor is 2.5 times larger than in soft diffraction one of the main reasons for repeating measurement in Run II with an improved forward detector system ~ 20 b  momentum fraction of parton in “Pomeron” EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production Puzzles from run I Run I gap fractions are suppressed relative to theory predictions, both for soft (Regge) and hard diffraction …but factorization holds among processes at the same energy, just like at HERA DSF at √s=1800 GeV suppressed by factor ~ 20 while Regge by factor ~8  contradicts RENORM prediction, but…see further down in the talk EDS-2011 Vietnam CDF Diffraction and Exclusive Production

The CDF II Detector – plan view EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production The MiniPlugs @ CDF 3.5<|h|<5.1 EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Measurements w/the MiniPlugs MP TOWER STRUCTURE MULTIPLICITY @ POSITION ENERGY ADC counts in MiniPlug towers in a pbar-p event at 1960 GeV. “jet” indicates an energy cluster and may be just a hadron. 1000 counts ~ 1 GeV NIM A 430 (1999) NIM A 496 (2003) NIM A 518 (2004) Multiplicity of SD and ND events EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production Diffractive W/Z In LO QCD W probes the quark content of diffractive exchange. Production by gluons is suppressed by a factor of aS and distinguished by an associated jet. MW EDS-2011 Vietnam CDF Diffraction and Exclusive Production

MW from inclusive We/m+v Method: compare transverse MW data with MC MWdiff= 80.9± 0.7(GeV/c2) EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Data and event selection 0.6 fb-1 of integrated luminosity data W Z EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Diffractive W/Z fractions ~80% ~87%% 68-80% f1-int =(25.6±1.2)% Run I: RW =1.15±0.55 % for xmin< x <0.1  [0.88±0.21 (stat)% within 0.03 < x < 0.10 & |t|<1 EDS-2011 Vietnam CDF Diffraction and Exclusive Production

DSF from Dijets in Run II ) (x F Bj ND jj SD Rate R(x Þ º xBj-distribution of SD/ND ratio has no strong Q2 dependence slope of t-distribution is independent of Q2 for |t| < 1 (GeV/c)2 does the t-distribution have a diffraction minimum beyond |t|=1 GeV/c)2??  stay tuned, release coming soon! EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Dijet ET distributions  similar for SD and ND over 4 orders of magnitude Kinematics EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Q2 dependence of DSF in dijets ETjet ~ 100 GeV ! Small Q2 dependence in region 100<Q2<10 000 GeV2 where dsSD/dET & dsND/dET vary by a factor of ~104 !  The Pomeron evolves as the proton ! EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Diffractive structure function – Run II t - dependence Fit ds/dt to a double exponential: No diffraction dips at |t| < 1 GeV2 No Q2 dependence in slope from inclusive up to Q2~104 GeV2 Same slope over entire region of 0 < Q2 < ~ 10 000 GeV2! EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production sTSD and dijets p e g* p soft dijet p p p ~8 ZEUS and H1 vs. CDF H1 ZEUS CDF KG, PLB 358 (1995) 379 sTsd ~ 8 b Magnitude: same suppression factor in soft and hard diffraction! Shape of b distribution: ZEUS, H1, and Tevatron – why different slapes? EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production GAPS BETWEEN JETS Jet gap analysis nears completion repeat at LHC at 7 TeV with higher ET forward jets EDS-2011 Vietnam CDF Diffraction and Exclusive Production

EXCLUSIVE Dijet Excl. Higgs THEORY CALIBRATION p _ } JJ gg cc PRD 77, 052004 (2008) PRL 99, 242002 (2007) PRL 242001 (2007) Exclusive dijets EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Exclusive gg production Phys.Rev.Lett. 99,242002 (2007) ET > 5 GeV ||< 1.0 3 gg / popo evts observed 2  candidates 1 00 candidate V.A.Khoze et al. Eur. Phys. J C38, 475 (2005): 2 events   ~ 90 fb, in agreement with theory cannot claim discovery as bgd study was made a posteriori EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Exclusive Dimuon Production p+p→p++-+p 3 GeV/c2 <M<4 GeV/c2 many physics processes in this data set:  c exclusive c in DPE EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production Exclusive J/ and (2s) J/ production 243 21 events d/dy|y=0= 3.92 ± 0.62 nb Theoretical Predictions 2.8 nb [Szczurek07,], 2.7 nb [Klein&Nystrand04], 3.0 nb [Conclaves&Machado05], and 3.4 nb [Motkya&Watt08]. Y(2s) production 347 events d/dy|y=0 = 0.54 ± 0.15 nb R = (2s)/J/= 0.14 ± 0.05 In agreement with HERA: R = 0.166 ± 0.012 in a similar kinematic region PRL 242001 (2009) J/ Fit : 2 Gaussians + QED continuum (2s) QED continuum EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Exclusive c→J/(→+-)+ PRL 242001 (2009) Allowing EM towers (ET >80MeV) large increase in the J/y peak & minor change in the y(2s) peak  Evidence for: c→J/+ production J/y 286 352 = +66 events Y(2s) 3940 = +1 event Allow extra EM tower d/dy|y=0 = 75 ± 14 nb, compatible with theoretical predictions 160 nb (Yuan 01) 90 nb (KMR01) EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Exclusive gg production - new! (submitted to PRL: arXiv:1112.0858) EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Exclusive gg and e+e- events EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production Exclusive gg data vs. MC EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Exclusive gg cross section EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Exclusive gg event candidate EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Tevatron Low-s Energy Scan September 8-16 2011 √s=300 & 900 GeV (CDF already studied √s=630 , 1800 &1960 GeV) MinBias events (charged particle multiplicities, dN/dh, etc… Underlying event for various processes Gap-X-Gap events Tune MC generators Plan to have (some) results in summer conferences CDF data EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production SUMMARY Diffractive W and Z fractions: final results based on Run II CDF data using a Roman Pot Spectrometer (RPS) to measure the recoil pbar momentum The W fraction is in good agreement with the fraction measured in Run I based on a rapidity gap analysis The Z fraction is about 10% smaller than the W fraction, just as in non-diffractive events Diffractive structure function in dijet production: no strong Q2 and/or t dependence over a wide range is there a diffraction dip in the t-distribution?  coming soon Central rapidity gaps in min-bias and very forward dijet events: same dependence on Dh=hmax- hmin Exclusive production observed/measured for several processes thank you for your attendance EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production BACKUP EDS-2011 Vietnam CDF Diffraction and Exclusive Production

DIFFRACTIVE AND NON-DIFFRACTIVE INTERACTIONS Non-diffractive  no “large” gaps Color-exchange Diffractive  gaps Colorless exchange with vacuum quantum numbers Incident hadrons acquire color and break apart CONFINEMENT rapidity gap p Incident hadrons retain their quantum numbers remaining colorless pseudo- DECONFINEMENT POMERON p p p p Goal: understand the QCD nature of the diffractive exchange EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Gap survival probability EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Dynamic Alignment of RPS Detectors Method: iteratively adjust the RPS X and Y offsets from the nominal beam axis until a maximum in the b-slope is obtained @ t=0. Limiting factors 1-statistics 2-beam size 3-beam jitter @ CDF W/lowlum data EDS-2011 Vietnam CDF Diffraction and Exclusive Production

x & b dependence of FDjj – Run I Pomeron dominated EDS-2011 Vietnam CDF Diffraction and Exclusive Production

Diffractive dijets @ Tevatron p jet reorganize EDS-2011 Vietnam CDF Diffraction and Exclusive Production

CDF Diffraction and Exclusive Production Diffractive DIS @ HERA J. Collins: factorization holds (but under what conditions?) Pomeron exchange Color reorganization e Q2 g* p jet x reorganize e g* x,t p IP Results favor color reorganization EDS-2011 Vietnam CDF Diffraction and Exclusive Production