New Results on Diffractive and Exclusive Production from CDF Konstantin Goulianos The Rockefeller University (for the CDF Collaboration) DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 1

CONTENTS  Introduction  Diffraction in QCD  Diffraction at CDF Definitions Factorization breaking in soft diffraction Exclusive production of: dijet-2008, dimuon   c -J/  (2s)-2009,   Central Exclusive Production of  +  -  NEW! DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 2

DIFFRACTION IN QCD Diffractive events  Colorless vacuum exchange   -gaps not suppressed Non-diffractive events  color-exchange   -gaps exponentially suppressed POMERONPOMERON Goal : probe the QCD nature of the diffractive exchange rapidity gap p ppp p DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 3

DIFFRACTION AT CDF Single Diffraction or Single Dissociation Double Diffraction or Double Dissociation Double Pom. Exchange or Central Dissociation Single + Double Diffraction (SDD) SD DD DPE/CD SDD Elastic scatteringTotal cross section  T =Im f el (t=0) OPTICAL THEOREM   gap   JJ, b, J/   W p p JJ …ee…  exclusive DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 4

DEFINITIONS MXMX dN/d  ,t,t p’ rap-gap  =-ln  0 ln s ln Mx 2 ln s since no radiation  no price paid for increasing diffractive-gap width pp p MXMX p p’ SINGLE DIFFRACTION DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 5 Forward momentum loss

Factor of ~8 (~5) suppression at √s = 1800 (540) GeV  diffractive x-section suppressed relative to Regge prediction as √s increases see KG, PLB 358, 379 (1995) 1800 GeV 540 GeV M ,t,t p p p’ √s=22 GeV RENORMALIZATION Regge FACTORIZATION BREAKING IN SOFT DIFFRACTION CDFCDF DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 6 Interpret flux as gap formation probability that saturates when it reaches unity

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 7 EXCLUSIVE Dijet  Excl. Higgs T HEORY CALIBRATION p p _ } JJ  c Exclusive dijets PRD 77, (2008) PRL 102, (2009)

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 8 Exclusive  c Exclusive dimuon production 3 GeV/c 2 <M  <4 GeV/c 2 p+p →p+  +  - +p PRL 102, (2009)  Several physics processes in this dataset: _ _

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 9 Exclusive  c Exclusive  c →J/  (→  +  - )+   Allowing EM towers (E T >80MeV)  large increase in the J/  peak & minor change in the  (2s ) peak  Evidence for:  c →J/  +  production J/  286  352 = +66 events  (2s) 39  40 = +1 event d  /dy| y=0 = 75 ± 14 nb, compatible with theoretical predictions  160 nb (Yuan 01)  90 nb (KMR01) Allow extra EM tower PRL 102, (2009)

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 10 Exclusive  c Exclusive J/  and  (2s) J/  producton 243  21 events d  /dy| y=0 = 3.92± 0.62 nb Theoretical Predictions 2.8 nb [Szczurek07,], 2.8 nb [Szczurek07,], 2.7 nb [Klein&Nystrand04], 2.7 nb [Klein&Nystrand04], 3.0 nb [Conclaves&Machado05], and 3.0 nb [Conclaves&Machado05], and 3.4 nb [Motkya&Watt08]. 3.4 nb [Motkya&Watt08].  s  production 34  7 events 0.54 d  /dy| y=0 = 0.54 ± 0.15 nb R =  (2s)/J/  = 0.14 ± 0.05 In agreement with HERA: R = ± in a similar kinematic region J/   (2s) QED continuum

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 11 Exclusive  production-2012 PRL 108, (2012)

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 12 Exclusive  and e + e - events

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 13 Exclusive  data vs MC

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 14 Exclusive  cross section 14

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 15 Exclusive  event candidate

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 16 Central Exclusive Poroduction of  +  - DETECTOR NOT USED NOT UED use only |  |=

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 17 Central Exclusive Production of  +  -  TRIGGERS  Two Central Calorimeter towers (|  |<1.3) w/E≥0.5 GeV (a very low threshold) and no energy in BSC (|  |= ) and in the Forward Plug Calorimeters (|  |= ).  “zero-bias” bunch crossing events with no tracks  to study noise/exclusivity cuts.  DATA SETS  Recorded 90(22)×10 6 events at√s=1960 (900) GeV.  PRELIMINARY RESULTS  |y(  +  - )|<1.0, M  +  - <0.8 where there is some acceptance at all p T. Notice: no particle ID is (yet) being used and the observed tracks are assumed to be due to pions (until further notice – stay tuned!). NEW DATA

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 18 “Empty” events  detector noise levels  Detector noise levels:  Determined separately for interaction and no-interaction events  Rejected “noise” events below vertical dashed lines  Empty-event selection  Select region of bunch luminosity with low overlaps and high yied use data only here

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 19 M  +  - distributions at 1960 GeV  not-corrected for acceptance  corrected for acceptance  we clearly see f 0 (980), f 2 (1270) and f 0 (1370).  the small but significant peak at 3.1 GeV is understood to be from J/   e + e - with masses assumed as m  + m  -.

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 20 Event ratio of 1960/900 GeV and average P T at 1960 GeV  Ratio of candidates at √s=1960/900 GeV vs M(pair)   Mean p T (pair) in GeV/c as a function of M(pair) 

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 21 Comparisons of d  /dM  events per bin  The structures observed in the mass region of less than ≈1 GeV are under investigation.

DIS-2013, Marseille Diffractive and Exclusive Production at CDF K. Goulianos 22 SUMMARY  Reviewed briefly exclusive production at CDF.  Measured exclusive  +  - production (no particle ID yet, tracks assumed to be due to pions) at √s=900 GeV and √s=1960 GeV with higher statistics than in earlier studies.  Explored the low mass region: found well known structures from AFS at ISR at √s=63 GeV for M    GeV.  Partial wave analysis currently underway – stay tuned! Thank you for your attention