CDF. The Future of QCD at the Tevatron Fermilab, May The Rockefeller University. Konstantin Goulianos

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$Diffraction @ CDF Konstantin$ University The Future of QCD

1 CDF Konstantin Goulianos The Rockefeller University The Future of QCD at the Tevatron Fermilab, - May 4

$Future of QCD: Diffraction @CDF K.$

2 CDF Run I results Fermilab - May 4 The Future of QCD: K. Goulianos

3 Run I Run # Dates b - Physics ~5 Elastic, Diffractive & Total x-sections -A,B ~ Raidity Gas -C ~ Roman Pots Fermilab - May 4 The Future of QCD: K. Goulianos 3

$Run - (988-89) Elastic, single diffractive, and total cross sections @ 546 and 8 GeV Roman Pot Sectrometers Roman Pot$ $σ tot ~ s ε Elastic cross section dσ/dt ~ ex[α lns] shrinking forward eak Single diffraction Additional Detectors$

4 Run - (988-89) Elastic, single diffractive, and total cross 546 and 8 GeV Roman Pot Sectrometers Roman Pot Detectors Scintillation trigger counters Wire chamber Double-sided silicon stri detector Results Total cross section σ tot ~ s ε Elastic cross section dσ/dt ~ ex[α lns] shrinking forward eak Single diffraction Additional Detectors Trackers u to η = 7 Breakdown of Regge factorization Fermilab - May 4 The Future of QCD: K. Goulianos 4

5 Total & Elastic Cross Sections (Run I-) σ ( s) = σ T φ o s ε y = ln s = σ ε y The exonential rise of σ T is a QCD asect exected in the arton model (see E. Levin, An Introduction to Pomerons,Prerint DESY 98-) o e y Im f el φ ( s, t) y = ln s e ( ε + α t ) y y Fermilab - May 4 The Future of QCD: K. Goulianos 5

6 Soft Diffraction (Run I-) σ dtdξ Unitarity roblem: With factorization and std omeron flux σ SD exceeds σ T at s TeV. Renormalization: normalize the omeron flux to unity KG, PLB 358 (995) 379 ξ. min t= f IP/ (t,ξ) dξ dt = d SD = f IP/ (t, ξ) σ IP (M X ) σ SD ~ s ~ ε Fermilab - May 4 The Future of QCD: K. Goulianos 6

7 M -scaling KG&JM, PRD 59 (999) 47 Factorization breaks down in favor of M -scaling renormalization σ ε d s + ε dm (M ) std. and renorm. flux fits ε =.5 =.5 renorm. flux rediction... 4 GeV (. < ξ <.3) GeV (. < ξ <.3) 546 GeV (.5 < ξ <.3) 8 GeV (.3 < ξ <.3) (M ) GeV std. flux rediction 8 GeV std. flux rediction Fermilab - May 4 The Future of QCD: K. Goulianos 7

8 QCD Basis for Renormalization (KG, he-h/54) t y y indeendent variables: d dt t, y σ = C F ( t) d y Ga robability ε y ~ e { ( ε + α t ) y} { ε y e κ σ e } y= ln s y Fermilab - May 4 The Future of QCD: K. Goulianos 8 color factor min κ = o g IP IP IP ( t) β () IP.7 ε y s s ε Renormalization removes the s-deendence M -SCALING

9 κ and ε Exerimentally: κ = KG&JM, PRD 59 (47) 999 Color factor: Pomeron intercet: Q κ = f f = g = q N N 8 3 ε c g IP IP IP β IP = g q q =.7 ±., ε =.4 λ g w + λ w =. c.8 λ HERA x f(x) = x λ f g =gluon fraction f q =quark fraction x f (x) - λ g =. λ q =.4 λ R =-.5 Q = GeV gluon valence quarks sea quarks x Fermilab - May 4 The Future of QCD: K. Goulianos 9

10 Run-IC CDF-I Run-IA,B η = CENTRAL MUON UPGRADE STEEL ABSORBER CENTRAL MUON CENTRAL HADRON Central Muon Extension END WALL HADRON η =.9 CDF Detector CES CPR CENTRAL EM SOLENOID CENTRAL TRAKCING CHAMBER END PLUG EM END PLUG HADRON η =.4 EM Forward (Not-To-Scale) HADRON DIPOLE MAGNETS - CDF Vertex Tracking Chamber Silicon Vertex Detector INTERACTION POINT BBC Z η = 4. x= x<.97 ROMAN POTS at 57 m Scintillator fiber xy-tracker 7 µ itch, m lever arm Accetance: < t <,.3< ξ <. Forward Detectors BBC 3.<η<5.9 FCAL.4<η<4. Fermilab - May 4 The Future of QCD: K. Goulianos

11 Soft Central and Double Gas IP M M η min dn dη η max ln M ln M ln s η Double Diffraction Dissociation One central ga η _ η η IP IP Double Pomeron Exchange Two forward gas IP t IP t M M η min η max ln M ln M ln/ξ ln s ln s η SDD: Single+Double Diffraction One forward + one central ga Fermilab - May 4 The Future of QCD: K. Goulianos

12 Generalized Renormalization (KG, he-h/54) d 5 indeendent variables 5 i= 5 σ dv i = C F ( t) i= - y y Ga robability y= y { ( ε + α t ) } i yi ε ( y + y ) e κ σ e { } Fermilab - May 4 The Future of QCD: K. Goulianos y y y t y = y + y ε y ~ e ln s y s min ε s ε t o y color factors Sub-energy cross section (for regions with articles) Same suression as for single ga!

13 Central & Double-Ga Results events s=8 GeV Differential shaes agree with Regge redictions DATA DD + non-dd MC non-dd MC s = 8 GeV.35 ξ-.95 t- DD SDD DPE. GeV η =η max -η min events s=8 GeV DATA SDD + SD MC SD MC η ex =η max -η min Number of Events er logξ = CDF Preliminary M X ( GeV ) Data DPE MC SD MC DPE+SD MC ξ X σ DD (mb) for η > 3. One-ga cross sections are suressed Two-ga/one-ga ratios are κ =. 7 CDF UA5 (adjusted) Regge Renormalized ga ga fraction η > 3. - CDF: one-ga/no-ga CDF: two-ga/one-ga Regge rediction Renorm-ga rediction -ga -ga Fraction of Events with ξ < CDF Data: DPE/SD ratio (Preliminary) Regge + Factorization Ga Probability Renorm. Pomeron Flux Renom. 3 s (GeV) 3 sub-energy s --, (GeV) 3 s (GeV) Fermilab - May 4 The Future of QCD: K. Goulianos 3

14 Soft Ga Survival Probability ga fraction η > 3. CDF: one-ga/no-ga CDF: two-ga/one-ga Regge rediction Renorm-ga rediction -ga S = ga/ ga S ga/ ga(8 GeV).3 - -ga ga/ ga S ga/ ga(63 GeV).9 3 sub-energy s --, (GeV) Fermilab - May 4 The Future of QCD: K. Goulianos 4

15 Soft Diffraction Conclusions Exeriment: M scaling Non-suressed double-ga to single-ga ratios Phenomenology: Generalized renormalization Obtain Pomeron intercet and trie-pomeron couling from inclusive PDF s and color factors Soft diffraction is understood! (?) Fermilab - May 4 The Future of QCD: K. Goulianos 5

16 Hard Diffraction Diffractive Fractions Diffractive Structure Function Factorization breakdown and restoration DSF from inclusive PDF s Hard diffraction conclusions Fermilab - May 4 The Future of QCD: K. Goulianos 6

17 Diffractive Fractions X + ga SD/ND fraction at 8 GeV Jet + ga + Jet DD/ND ga fraction at 8 GeV X W JJ b J/ψ Fraction(%).5 (.55).75 (.).6 (.5).45 (.5) All SD/ND fractions ~% Gluon fraction =.54 ±.5 Suression by ~5 relative to HERA f g ga survival robability ~% Factorization Tevatron at 8 GeV (single energy) Fermilab - May 4 The Future of QCD: K. Goulianos 7

18 Diffractive Structure F n + + Jet + Jet + X Measure ratio of SD/ND dijet rates as a f n of x R SD ND g,q (x / ) (3) i = R x In LO-QCD ratio of rates =.45 equals ratio of structure fn s F jj (x E i T s e x η i C F ) = x g(x ) + (qi(x ) + qi(x )) CA SD/ND Rates vs x Fermilab - May 4 The Future of QCD: K. Goulianos 8

19 Breakdown of QCD Factorization HERA The clue to understanding the Pomeron TEVATRON e γ* IP ξ,t H CDF IP ga η dn/dη ga η dn/dη F ( Q, x) F D ( Q, β, ξ, t )??? F F JJ D JJ Jet ( E, x) Jet ( E, β, ξ, t) T T Fermilab - May 4 The Future of QCD: K. Goulianos 9

20 Restoring Diffractive Factorization ND jet jet F D jj (β) from DPE/SD,. ξ.3 from SD/ND,.35 ξ.95 η _ SD DPE jet jet jet η jet η IP IP IP DSF from single-gas R(SD/ND) R(DPE/SD) DSF from double-gas: Factorization restored!.. β Fermilab - May 4 The Future of QCD: K. Goulianos

21 DSF from Inclusive df s (KG) x f (x) - ε g =. ε q =. 4 ε R =-.5 Q = GeV gluon valence quarks sea quarks x F D ( Q, x, ξ ) ξ ε F ( x f ( x) = x ε Power-law region ξ max =. x max =. β <.5ξ, x) x f (x) - C( Q ) ξ ε + βξ λ ( ( ) λ g =.5 λ q =.3 Q + Q ) Q = 75 GeV gluon valence quarks sea quarks x ANORM C κ + ξ ε+ λ β λ HERA(no RENORM ): TEVATRON (RENORM) R DDIS DIS : R fixed ( x) ξ constant SD ND ( ε + λ ) () x x ( ) ε = ε + λ Q DDIS Fermilab - May 4 The Future of QCD: K. Goulianos

22 Pomeron Intercet from H α IP () H Diffractive Effective α IP () (rel) 999 (rel).3 Inclusive. α ( t) =+ ε + α t IP +λ RENORM. ( Q = ) soft IP - Q [GeV ] Fermilab - May 4 The Future of QCD: K. Goulianos

23 ξ-deendence: Inclusive vs Dijets x f (x) λ g =.5 Q = 75 GeV gluon valence quarks sea quarks λ q =.3 F jj (x x 4 ) = x g(x ) + (qi(x ) + qi(x )) 9 dσ incl dξ constant Pomeron+Reggeon F β ξ ( β,ξ) (n =. ±., m =.9.) D jj ± n m Pomeron dominated Fermilab - May 4 The Future of QCD: K. Goulianos 3

24 Enery Deendence of F JJ D Phenomenological Models: Renormalization Phys. Lett. B 358, 379 (995). Ga survival robability, e.g. Eur.Phys. J. C, 5 (). Soft color interactions Phys. Rev. D 64, 45 (). R 63/8 (redicted) ~ R 63/8 =.3±.(stat)+.4/-.3(syst) Fermilab - May 4 The Future of QCD: K. Goulianos 4

25 Hard Diffraction Conclusions Diffraction aears to be a low-x exchange subject to color constraints Fermilab - May 4 The Future of QCD: K. Goulianos 5

26 Summary of Run I Results SOFT DIFFRACTION M scaling Non-suressed double-ga to single-ga ratios HARD DIFFRACTION Flavor-indeendent SD/ND ratios Factorization breakdown and restoration Universality of ga rob. across soft and hard diffraction Fermilab - May 4 The Future of QCD: K. Goulianos 6

27 Run II Diffractive Program Single Diffraction ξ and Q deendence of F jj D Process deendence of F D (W, b,j/ψ,...) Double Diffraction Jet-Ga-Jet: η ga for large fixed η jet Double Pomeron Exchange F jjd on -side vs ξ-bar Also: Exclusive central roduction Dijets, χ c, low mass states, Higgs(!)(?) Other Oen to suggestions Fermilab - May 4 The Future of QCD: K. Goulianos 7

$Diffraction @CDF K.$

28 CDF-II Tag leading < ξ<. Reject (retain) 95% of ND (SD)events detect forward articles Fermilab - May 4 The Future of QCD: K. Goulianos 8

reflective Al sheets and guided into bunches to be viewed individually by

29 MiniPlug Calorimeter About 5 wavelength shifting fibers of mm dia. are strung through holes drilled in 36x¼ lead lates sandwiched between reflective Al sheets and guided into bunches to be viewed individually by multi-channel hotomultiliers. Fermilab - May 4 The Future of QCD: K. Goulianos 9

$5 in Fermilab - May 4 The Future of QCD: Diffraction @CDF$

30 Artist s View of MiniPlug 84 towers 5 in 5.5 in Fermilab - May 4 The Future of QCD: K. Goulianos 3

x IP F D(3)(x IP,β,Q ).5.5.5 x IP =.3 H reliminary x=.3, β=. x=., β=.4 x=.3, β=. Q deendence of DSF F (x,q ).5 x=.6, β=..5 x=., β=.4.5.5 x=.95, β=.65 x=.7, β=.9 Q [GeV ] F D(3) (x IP,β,Q ) H rel.

31 x IP F D(3)(x IP,β,Q ) x IP =.3 H reliminary x=.3, β=. x=., β=.4 x=.3, β=. Q deendence of DSF F (x,q ).5 x=.6, β=..5 x=., β= x=.95, β=.65 x=.7, β=.9 Q [GeV ] F D(3) (x IP,β,Q ) H rel. F (x,q ) H R D F (Q, x, ξ) F(Q, x) ~ no Q deendence ~ flat at HERA ~ /x.5 at Tevatron Pomeron evolves similarly to roton excet for for renormalizartion effects Fermilab - May 4 The Future of QCD: K. Goulianos 3

$Hard Double Diffraction + Jet + Ga + Jet y y ga$ ?? jet y y R J G J LHC J G J R TEV (s ) = /S %/.

32 Hard Double Diffraction + Jet + Ga + Jet y y ga jet Run I Results Question ga??? jet y y R J G J LHC J G J R TEV (s ) = /S %/. 5% Fermilab - May 4 The Future of QCD: K. Goulianos 3

$Exclusive Dijets in DPE Interest in diffractive Higgs roduction Calibrate on$ excl jj DPE (R >.8) 97 ± 65 ± 7 b 34 ± 5 ± b jj no eak!

33 Exclusive Dijets in DPE Interest in diffractive Higgs roduction Calibrate on exclusive dijets Dijet mass fraction R = jj M M cone jj X E jet T GeV 5 GeV σ excl jj DPE (R >.8) 97 ± 65 ± 7 b 34 ± 5 ± b jj no eak! Uer limit for excl DPE-jj consistent with theory Fermilab - May 4 The Future of QCD: K. Goulianos 33

34 Search for Exclusive χ + + χ c ( J/ψ + γ) + Events are triggered on dimuons Select muons with P T >.5 GeV, η <.6 Reject cosmic rays using time of flight information Select events in J/ψ mass window χ c candidates No ositive identification of χ c events Cross section uer limit comarable to KMR rediction Fermilab - May 4 The Future of QCD: K. Goulianos 34

35 Merits/Problems/Needs Merits of CDF Run II diffractive rogram Measuring ξ with calorimeters full accetance overla rejection BSC ga triggers can take data at high luminosities But: BSC ga rejects some diffractive events from MP sillover Useful rates too low for many rocesses, e. g. exclusive b-bbar Need: Low luminosity runs for calibrations: ξ-roman ot vs ξ-calorimeter BSC ga trigger vs roman ot trigger Also need: $$$ to instrument MPs from current 84 to all 56 channels for EM/hadron discrimination and better jet definition Fermilab - May 4 The Future of QCD: K. Goulianos 35

36 CONCLUSION Run II CDF has a comrehensive Run II diffractive rogram Modest ugrades & secial runs are desirable Full MiniPlug instrumentation Low luminosity (~ 3 ) runs for calibrations Data run at 63 GeV Beyond Run II Can think of imrovements, but of no comelling diffractive hysics that cannot be done in Run II Fermilab - May 4 The Future of QCD: K. Goulianos 36

Diffraction and Exclusive (Higgs?) Production

$Diffraction and Exclusive (Higgs?) Production$ Diffraction and Exclusive (Higgs?) Production from CDF to LHC Konstantin Goulianos The Rockefeller University Les Rencontres de hysique de la Valle e d Aoste 4-10 March 007, La Thuile, Italy Recent references: