7/8/2016James L Pinfold Manchester Exclusive      Production in the Upsilon Region at CDF Forward Physics at the LHC Manchester 2010 James L Pinfold University of Alberta Forward Physics at the LHC Manchester 2010 James L Pinfold University of Alberta

7/8/2016James L Pinfold Manchester Muon Chambers CDF Detector CDF Detector A Roman Pot deployed detector is placed on one side of CDF at at 60m from the IP. RPS acceptance ~80% for 0.03 < ξ < 0.1 and |t| < 0.1)

7/8/2016James L Pinfold Manchester Central Exclusive Physics Central Exclusive Physics Central state ,  P, PP Proton/antiproton does not break up during interaction Both protons coherently scattered. Central state fully specified and measured, unlike “inclusive” production: > 3 rap-gap Mass to ~3 GeV at ISR, ~100 GeV at Tevatron, ~700 GeV at LHC Forward tagging of the p’s at the LHC with FP420/ 220m allows full reconstruction of the central state  ~180 o  p T ~ 0

7/8/2016James L Pinfold Manchester Exclusive Production Diagrams Exclusive Production Diagrams Gamma-gamma Photoproduction QCD p p g g g X q-loop  X IP QCD DPE gap In perturbative QCD the lowest order prototype of the pomeron is the color neutral system of two gluons. Central Exclusive Production (b) Υ(1S) Υ(2S) Υ(3S) bb

7/8/2016James L Pinfold Manchester Exclusive     Production in the J/  Region Exclusive     Production in the J/  Region Trigger (DIFF_CHIC_CMU1.5_PT1.5_TRK): –BSC Gap, east & west –muon + track (p t > 1.3 GeV/c; |  | < 1.2) – 3.0 < M(muon + track) < 4.0 GeVc 2 The existing sample corresponds to a lumi of 1.48 fb -1 Offline cuts –No other activity in the events (to an |  | of 7.4) –P T (  ) > 1.4 GeV/c & |  (  )| < 0.6 –Cosmic ray cuts (abs (  TOF ) < 3 ns) –Exclusivity cuts (same as for the e + e - paper) STARLIGHT Monte Carlo simulation used (Klein & Nystrand) p + p  p +      + p

7/8/2016James L Pinfold Manchester Exclusive     Production in the J/  Region Example exclusive  +  - event: Run , Event

7/8/2016James L Pinfold Manchester events Fit: 2 Gaussians + QED continuum. Masses 3.09, 3.68 GeV == PDG Widths 15.8,16.7 MeV=resolution. QED = generator x acceptance 3 amplitudes floating J   s  (with no EM shower) Exclusive     Production in the J/  Region

7/8/2016James L Pinfold Manchester Similar selection as     search with additional isolated EM shower req.  c  J/  (     ) +  (soft) (1)  c  J/  (     ) +  (soft) (1)  DPE QCD Plot show fit of ET spectrum for events from J/  peak with: –E EM T tower > 100 MeV Total number of  c events: 68.2 ±  c events above the 80 MeV exclusivity cut 4.0 ± 1.6%  c event background to exclusive J/  signal

7/8/2016James L Pinfold Manchester The measured cross-section agrees -within theoretical errors - with: –The predictionof Khoze, Martin & Ryskin EPJ C19, 447 (2001), Erratum C (2001) & Khoze, Martin, Ryskin & Stirling, Eur.Phys.J.C35: ,2004 –The calculation of Pasechnik, Szczurek & Teryaev, arXiv: [hep-ph]. In this analysis it is assumed that the produced  c is 0 ++ (J PC )(BR~1%) –NB double-diffractive production of exclusive axial vector (1 ++ ) & tensor (2 ++ ) quarkonium states are strongly suppressed (Khoze, Martin & Ryskin, EPJ C19, 447 (2001) Caveat: large BR of the  c (1++) (34%) to J/  means it may contribute to signal Exclusive  c Production - Results Exclusive  c Production - Results IP + IP  c  J/       (soft) Theory 90 nb

7/8/2016James L Pinfold Manchester Exclusive production of      ,  (1S,2S,3S),  b Exclusive     Production in the Υ Region Cross-sections are down by 2 orders of magnitude – thus we have to change our analysis strategy for exclusives – we need to deal with pile-up Predictions of d  /dy| y=0, from: Motyka and Watt arXiv: pb Cox, Forshaw & Sandapan - 12  1 pb Klein& Nystrand ~12 pb Bzdak,Motyka,Szymanowski & Cudell 0.8 – 5 – 9 pb

7/8/ Now apply “super clean” exclusivity cuts as in low mass (J/  ) exclusive  -pair analysis i.e. no pile-up, and only  -pairs detected Superclean Upsilon 6 events in the 8 – 12 GeV/c 2 region 4 events with mass > 12 GeV/c 2. (Most of reduction is killing pile-up)    ETET James L Pinfold Manchester 2010 Plugs, Miniplugs, CLC, BSC empty Run/Event: / Lego, threshold E T > 10 MeV M ~ 9.4 GeV Exclusive Upsilon Y(1S) Candidates Exclusive Upsilon Y(1S) Candidates

7/8/2016James L Pinfold Manchester STUDY ANALYSIS STRATEGY USING       -  IN UPSILON REGION – THEN APPLY TO UPSILON ANALYSIS Find Exclusive events using –Number of tracks associated with    - vertex = 0 –Kinematics:   180 o,  p T  0, (or  P T  0) Trigger: 2 central muons with p T > 4 GeV/c L = 1.14±.06 fb −1 utilized (6% error assumed) ~ 3 M events. Remove cosmic rays (timing + collinearity) Require on beam-line. Count additional (associated) tracks (n_ass) within 2 mm of     vertex. Cleanliness, backgrounds & acceptances being studied. Analysis Strategy Analysis Strategy

7/8/2016 James L Pinfold Manchester To be assigned to a vertex |z(  1 ) - z(  2 )| ≤ 2.0 mms The  -pair z-vertex is defined as the [z(  1 )+z(  2 )]/2.0 A track is associated if it lies within ± 2.0 mms of the  -pair z-vertex We are studying using smaller associated track regions Definition of Associated Tracks Definition of Associated Tracks

Search for/measurement of photoproduction of Y(1S),Y(2S),Y(3S) (not before seen in hadron-hadron) Blessed plots have lower lumi: L = 890 pb -1 ~ 2.3 M events. Trigger: μ+μ- |η| 4 GeV/c “Preliminary look” exclusivity cuts” –p T (μμ) < 1.5 GeV/c –  > 120 degrees –0 associated tracks A “background” is expected from  b  Y(     - ) +  (soft) 7/8/2016 James L Pinfold Manchester Dimuons in the Upsilon Region Dimuons in the Upsilon Region Y(1S) Y(3S) Y(2S) Continuum

7/8/2016James L Pinfold Manchester HERA’s Upsilon States HERA’s Upsilon States H1 ZEUS Phys.Lett.B483:23-35 (2000) Phys.Lett. B437: (1998) H1 ZEUS

The inelastic events form a background to the truly exclusive events. The LPAIR MC predicts that with our final analysis cuts: 78% of events are truly exclusive, and 22% are inelastic (16% Elastic Inelastic + 6% Inelastic-Inelastic) NEW DEVELOPMENT – Pythia implementation of LPAIR algorithms will allow us to study proton breakup products and pass them thru CDFsim 7/8/2016 James L Pinfold Manchester Can We Tell Inelastic from Elastic Events? Can We Tell Inelastic from Elastic Events? LPAIR

7/8/2016 James L Pinfold Manchester Muon quality cuts Initial acceptance cuts (same as the trigger “cuts”) –p T (each muon) > 4.0 GeV/c –Pseudorapidity of each muon |  | < 0.6 –Assign to the various 7 mass ranges –Cosmic cuts, acollinearity < 3.05 radians Analysis cuts –π − φ ≤ 0.07 radians –p T (muon-pair) ≤ 0.8 GeV/c –Associate tracks = 0 Selection Cuts for QED Analysis Selection Cuts for QED Analysis MASS RANGES

7/8/2016James L Pinfold Manchester “Exclusive” QED      - will have n_ass=0 But there is background from events where the associated tracks are not seen (due to acceptance). We estimate this by linearly extrapolating the n_assoc track distribution into the n_assoc =0 bin In this example the background due to unobserved associated tracks is ~20 events out of 76. The linear extrapolation seems to be good in all mass ranges considered This approach to background subtraction is being studied Check Analysis in Presence of Check Analysis in Presence of Pileup Using QED     States (2) Pileup Using QED     States (2) EXAMPLE- FOR ILLUSTRATION ONLY

7/8/2016James L Pinfold Manchester Correct for efficiency, acceptance and perform background subtraction Calculate the QED cross-section for each QED mass region considered We get good agreement with the LPAIR MC (Vermaseren) prediction at all     masses As a check we divided the date into 3 regions according to the L inst of the event - LO (<45E30 ) MED(45E30-80E30) & HI ( <80E30) The integrated lumi that corresponds to each sample is 344.8, and 454 pb -1, respectively We see no systematic rise of the cross-section with luminosity Plots not blessed as yet Check Analysis in Presence of Check Analysis in Presence of Pileup Using QED     States (3) Pileup Using QED     States (3)

7/8/2016 James L Pinfold Manchester With some confidence that we can work with exclusive signals in the presence of pileup we are looking at the signals from the Upsilon Υ(1S,2S,3S) and  b  (Upsilon + soft photon) signal via the muon-pair final state. Choose events in acceptance with good quality + preliminary kinematic cuts (large box cuts) & CR veto To take account of the higher expected p T (muon-pair) and the larger value of  expected for such events we have changed the cuts to: 0.35 ≤ p T (muon-pair) ≤ 1.2 GeV/c  ≤  ≤ 0.15 Radians Clear Y(1s) and Y(2s) peaks seen (plots not blessed) “Small box” cuts Ongoing Work on Υ(1s,2s,3s) &  b Ongoing Work on Υ(1s,2s,3s) &  b b Υ(1S) Υ(2S) Υ(3S) bb b

7/8/2016James L Pinfold Manchester Exclusive  b  Search Exclusive  b  Search IP + IP  b        (soft) b Khoze, Martin, Ryskin, Stirling, Eur.Phys.J.C35: ,2004. It is a challenging task to separate  b from  (1s) production in the presence of pileup – –Looking at the use of kinematic constraints involving soft  (+     only vertex ) Hard to estimate number of events expected as there is only an upper limit for the BR[  b0 (1P)   (1s)] < 0.6 from Crystal Ball (Phys.Rev.DF34, 2611 (1986) However we now have a prediction for the BR[  b0 (J=0)   (1S)] ≈ 3% from Harland-Lang, Khoze, Ryskin and Stirling BIG background from  b production to  (1S) production –d  /dy(KMRS) = 200 pb if BR[  b   (1S)] ~ 4%   [  b   (1S)~ 8pb compared with ~10pb for exclusive Upsilon production

Exclusive di-leptons with 8 < M < 12 GeV/c 2 are rich in physics: –Photoproduction and DPE production of bottomonium states, –Important tests of p+H+p theory –Learning curve for FP420 calibration (p-scale & resolution) – expect ~5      - /hour at cm -2 s -1 at the LHC Tests of the analysis method using QED events (      - ) indicate that we can search for exclusive channels in the presence of pileup We are studying the background reduction, luminosity dependence and systematics of the search for exclusive Upsilon production We are also studying the use of kinematic constraints to allow us to separate  b       - from      -  - but this is challenging We also need to finalize the expected background from inelastic events We are working to complete this program within the next several months! 7/8/2016 James L Pinfold Manchester Conclusion Conclusion