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GTeV: Gluon Physics at the Tevatron

A future experiment at the Tevatron 2009: CDF & D0 complete data taking BTeV to run (if funded) 2009-2014(?) Primary Goal of GTeV: Non-perturbative QCD Uses CDF or D0 detectors as “core” Add precision forward and very forward tracking. GTeV: Gluon Physics at the Tevatron.

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GTeV: Gluon Physics at the Tevatron

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  1. A future experiment at the Tevatron 2009: CDF & D0 complete data taking BTeV to run (if funded) 2009-2014(?) Primary Goal of GTeV: Non-perturbative QCD Uses CDF or D0 detectors as “core” Add precision forward and very forward tracking GTeV: Gluon Physics at theTevatron

  2. Primary Goal: Understand Strong Interactions Foci: Determine glueball spectrum Relates to pomeron trajectories, strings, bags, lattice, potential etc Discover new exotic hadrons Hybrids, 4-quark, 5-quark, cubons !? Measure exclusive Relates to SM Higgs study at LHC Search for non-SM Higgs (CP-odd?) and other narrow scalars

  3. The REAL Strong Interaction extended, strong coupling classical limit? point-like, weak coupling • Many approaches • None complete: •  Regge Theory: Analyticity + • Unitarity + Crossing Symmetry • + Complex angular momenta • Lattice Gauge Theory Discrete spacetime, small volume Bag models Skyrmions • etc etc Want a complete S.I Theory Regge theory etc to be seen as “derivatives”

  4. Subset of proposed program could be done now, • except for: • Limit on number of triggers • bandwidth that would be allocated small • Students, postdocs want to discover H, SUSY, BH ... • (don’t we all!) • Dedicated program  >~ 1000 x the statistics • GTeV: Top priority to QCD, some other studies permitted • e.g. CDF, D0: NPQCD <~ 10%, other ~ 90% • GTeV: NP QCD ~ 90%, other <~ 10% • & need major upgrade of forward detectors

  5. 10 Billion 10,000,000,000 recorded events per year Maybe ~ 4,000,000,000 zero-bias (but not empty) events ~ 1 Khz to “tape” DAQ & Offline upgrades x 10

  6. Central Exclusive Production ... or, diffractive excitation of the vacuum It is contrary to reason to say that there is a vacuum or a space in which there is absolutely nothing. Descartes  Virtual states in the vacuum can be promoted to real states by the glancing passage of two particles.  Charged lepton (or q) pairs : 2-photon exchange  Hadronic states : 2-pomeron exchange (DPE) dominates Vacuum quantum number exchange. Central states’ quantum numbers restricted. Measure forward p,pbar  missing mass, Q-nos. Ideal for Glueball, Hybrid spectroscopy

  7. Central Exclusive Production • gg fusion: main channel for H production. • Another g-exchange can cancel color, even leave p intact. • p p  p + H + p • Theoretical uncertainties in cross section, involving skewed • gluon distributions, gluon k_T, gluon radiation, Sudakov ff etc. • Probably ~ 1 fb at Tevatron, not detectable, but may be possible at LHC (higher L and ~ 40 fb?) Khoze,Martin,Ryskin hep-ph/0111078 Lonnblad & Sjodahl hep-ph/0311252 and many others

  8. CP-Odd Higgs at Tevatron? • In SUSY can have CP-violation in Higgs sector • Higgses are CP-odd & CP-even mixtures • CP-odd component does not couple to W,Z • Even if M ~ 40 GeV would not have been seen at LEP Allowed regions ~ 20-60 GeV, tan beta ~ “few” • Will not be seen by standard associated WH,ZH at Tevatron, LHC Production through gg  top loop  H not suppressed But b-bbar b/g large too. Missing Mass resolution is critical !! ~ 250 MeV, then (30 ps timing in pots  where p,pbar are in bunches)

  9. Predictions for Tevatron: Khoze, Martin, Ryskin ~ 600 nb Feng Yuan ~ 735 nb (20 Hz at Tevatron!) GTeV: Acceptance  50%, 50K in 1 fb^-1 Measuring forward p  central quantum numbers 2+ forbidden at t=0 for state (Valery Khoze) If MM resolution <~ 100 MeV, exclusive test, resolve states

  10. Single Diffractive Excitation System X can be soft (all low pT) or hard (jets, W, Z). Pomeron trajectory probably different for hard and soft systems. Similar seen at HERA in Systematic study of trajectories, needs s-dependence • run at sqrt{s} = 630, 900, 1400, 1960 GeV (~ log spacing)

  11. BFKL and Mueller-Navelet Jets Color singlet (IP) exchange between quarks Enhancement over 1g exchange – multiRegge gluon ladder Jets with large y separation n minijets in between (inelastic case) large gap in between (elastic case) Fundamental empirical probe of new regime: non-perturbative QCD at short distances.

  12. Gluon Jets LEP(Z) ... ~ 10^7 q-jets, detailed studies “Pure” g-jet sample: 439 events (OPAL), also Delphi (less pure) (2 jets and ~ nothing else) ~ 99.9% pure g-jets q-jets suppressed by Jz = 0 rule

  13. Probing Very Small x Gluons High parton densities New phenomena (gluon saturation) HERA measures q(x) to ~ 10^-5 GTeV : measure g(x) to ~ 10^-4 (also x >~ 0.5) xF (see over) Hard to measure and c/b-tag v.forward jets Miniplug region (no tracking or tagging now) BTeV competition?

  14. Low-x Mapping: Forward probably best for lowest x gluons.

  15. Missing Mass! In science one must search for ideas. If there are no ideas, there is no science. Belinskii (Band) Extreme case of rest of detector completely empty Any MM peak crazy But threshold bump  pair production of e.g. LSPs Needs measurement of all forward particles Tracking + dipoles (?) Background from double beam halo: Timing (<~30 ps) on pots, Luminosity dependence

  16. Low pT is THE frontier of QCD [Bjorken] As pT drops from 200  100  50 MeV What happens? Larger distances: 1 f  4 fm How do gluon fields in protons “cut off” (not sharply(?)) Multiplicity distributions of very low pT particles, correlations, ... Low-pT cloud in special events [Runs with reduced field, Si-only tracking, etc ...................absorption and multiple scattering is limit] Large impact parameter, b collisions RHIC AA can measure b, how can we? Perhaps p[ qq .....q] (linear string, like meson) >> frozen (time dilation) Can collide aligned (small b) - --   - -- or across X I How select/study? Crazy ideas needed e.g. triple-Drell-Yan

  17. Non-Diffractive Events Inclusive production of many many hadrons (pT, y) Imagine with 1000 x the statistics! > Searches for new and rare (bbc !) states for hadron spectroscopy, > masses, lifetimes, production mechanisms, decay modes ... > beat data against PYTHIA and other MC of the future > c and b can be intrinsic (in p wave-fn) or created g g  Q Qbar > Probe small-x gluons (where they get dense!)

  18. Hadron Spectroscopy: an example X(3872) discovered by Belle (2003) Seen soon after by BaBar and CDF Relatively narrow What are its quantum numbers? Why so narrow? What is it? Google X(3872)  54,500 hits! See in exclusive DPE? Also, cross-section depends on “size/structure” of state.

  19. Hyperons Y and heavy flavor baryons Nice hyperon signals in Run 2 data with 2-track trigger. “High” p_T ... small acceptance. Looking now in 0-bias data. Best hope of finding most exotic states Main competition is BTeV Measure masses, lifetimes, BR’s, production mechanisms (Y-Y corrlns) excited states & combinations SELEX: doubly charmed baryons 

  20. Stringy Hadrons Mesons, Glueball, Baryon, Antibaryon Baryonium: 2 types? Really Exotics: Pentaquark Cubon  (!) Hybrid topology?

  21. Exotic Baryons Even without b-hadrons: There are many baryons with strange and charmed quarks. Many not yet seen (ccc) To say nothing of the b’s: bcs, bbc, bbb Can you think of any better way of producing and studying these than GTeV with 10^10? Not just stamp collecting, hadrons test non-perturbative QCD (Lattice or otherwise)

  22. Bose Einstein Correlations BEC Where do hadrons form? Local enhancement of identical bosons Size of hadron formation region Longitudinal and Transverse (3D) Powerful tool at RHIC in AA Study both in X and pGXGp events and “special” e.g. double Drell-Yan ! Study fermions too:

  23. Multiple Parton Scattering Infinite sea of partons as x 0 With valence(a) or with pion cloud (vacuum chiral condensate) (b) DPS = double parton scattering: pair-wise balancing 4 jets (or photon + 3 jets, or DY + 2-jets ...) Minijets ~ 5-10 GeV Results (“crude” from ISR, SPPS, Tevatron) Also: # of Minijets “measure” impact parameter (at least there’s a correlation) CDF 

  24. Antinuclei ISR Coalescence model: Overlap of wave-functions: Exercise: understand multiple baryon formation in hadron collisions Possible astrophysical interest: searches for antimatter in Universe (AMS) and in cosmic rays. This is the background

  25. Gluon initial states, mechanism unclear, surprises Color evaporation model: no polarization (isotropic) Non-relativistic QCD  polarization Soft g should couple more weakly to bb than cc – test CDF Polarization:

  26. Chung-I Tan (small-x & diffractive workshop) Strong Interactions and gravity, tied together with string! Nothing puzzles me more than time and space; and yet nothing puzzles me less, as I never think about them. Charles Lamb

  27. Detectors D0 an option I focus on CDF (tracking, hadron ID ...) Add: New pots very forward E&W: quad + near (55m) + far (120m?) Tracking |eta| > 2 (?) to beam pipe. Push low-beta quads back. Other forward detectors (tracking, upgrade calorimetry e.g.)? New DAQ and trigger system  kHz Silicon (certainly want it) ... hope it’s still good

  28. CDF Silicon VerteX Detector SVX For beauty, charm, tau identification and measurement. ~ 720,000 strips, 25um with 50um readout L00 : ~ 1.5 cm from x, R-phi view SVXII: 3 double 90 deg layers + 2 double 1.2 deg layers ISL : 1 or 2 double 1.2 deg layers. Impact parameter resolution ~ 30 um @ 1 GeV/c

  29. CDF Central Outer Tracker (COT) Drift chamber 3.1m in z, 0.34-1.32m in R 96 layers  30,240 s.wires 40 um gold-plated tungsten ADC & TDC each end 6 um Au-mylar field sheets Resolution ~ 150 um/wire

  30. Time of Flight Detector Surrounds Central Outer Tracker COT 140 cm ( ~ 4.7 ns) from beam. 216 scintillator bars, each ~ 4 cm x 4 cm Both ends read out: time and pulse height Design resolution = 100 ps Design optimized for B physics, K-pi separation.

  31. COMPARISON of TOF and COT dE/dx Thanks Kai Yi TOF Separation Power (sigma) <dE/dx> (CDF) p K p (GeV/c) Low p_T particles in range ~ 0.3 – 3.0 GeV/c, high identification probability

  32. Calorimetry in CDF em: Pb-scintillator had: Fe-scintillator + em shower position detector (strips) “New” (Run 2) Plug Central: 31x [3.2mm Pb + 5mm scint] + strip (2cm) chambers at 6 Xo 32x [25mm Fe + 10mm scint] Plug: 22x [4.5mm Pb + 4mm scint] + sh.max : 5mm scint strips at 6 Xo 23x [50mm Fe + 6mm scint]

  33. Below 3 degrees: (1) Cerenkov Luminosity Counters CLC Al mylar cones with isobutane radiator and 1” Ham R5800Q PMT 48 each end in 3 rings of 16 (2) MiniPlug Calorimeters 36x [4.8mm Pb + 6.4mm Sc] Liquid scint + wls fibers 18 Ham R5900 PMT each end

  34. New Forward Region (0.5-3.0 deg) ? Now: 48 CLC counters + Miniplugs Can (remove Q1 and) push back ~ 2 m low-beta quads Tracking e.g. GEM layers (50 um, 15 ns) over large area Possibility of forward dipoles (?) Deeper Calorimeter (~6 int. lengths?) high granularity, em/had Upgrade motivation, remembering BTeV ?? Full events + ? Very forward jets, Low-x, J G X G J etc.

  35. Very Forward: Roman Pots D0 has 8+8 quadrupole spectrometer pots + 2 dipole spect. pots Scintillating fiber hodoscopes (~ 1mm) CDF has 3 dipole spect. pots 0.8 mm x-y fibers GTeV: Quads + near + far dipoles Silicon ustrips, pixels, trig scint Quartz Cerenkov for ~ 30 ps TOF

  36. Roman Pot Acceptances (pbar) Q1h Q1v Q2h Q2v D55h D55v {CDF} D150h Acceptance (all pots) Sasha Drozhdin

  37. Add (repeat): New pots very forward E&W: quad + near (55 m) + far (120 m?)Tracking |eta| > 2 (?) to beam pipeOther forward detectors (calorimetry e.g.)?New DAQ and trigger system  kHzQuestion central tracking and hadron ID cf CDF Re-using D0 detector?

  38. Spaces for pots and their position: quad, near dipole, far dipole Replace 2(3) dipoles with 1(2) High Field dipole(s)  spaces 7.5 Tesla, same current, temperature! Missing mass resolution budget. limits? medium-beta? p-z corrln? Co-existence with BTeV: Luminosity (~4 e31, also high?), Harmonic number 1113 (1/6 arc separation) – RF, bunch structure, BB tune shift, Long-range tune shift, ES separators, L lifetime, ... Bunch-bunch variations, stability, drifts Instrumentation: precision BPMs at pots Contacts (so far): R.Dixon, V.Shiltsev, J.Marriner, A.Hahn, A.Drozhdin, N.Mokhov, M.Syphers, J.Johnstone, P.Garbincius, A.Zlobin, M.Martens, J.Strait ... Tevatron Issues

  39. GTeV plan GTeV Working Groups Topics Physics Total and Elastic Scattering Single Diffractive Excitation Low Mass Double Pomeron High Mass DPE & Higgs Jet-Gap-Jet Studies+BFKL Non-diffractive Interactions Small-x Hadron spectroscopy Charm and Beauty Exotica, extreme events Cosmic Ray issues Event Generators Detectors Simulations with Detectors Central detector Forward tracking, MPS Roman pots ("v.forward") DAQ & Trigger Triggers L1 L2 L3 kHz DAQ Computing on/off line, GRID Public database Tevatron High Field Dipoles Orbit issues, beta, ES seps Roman Pot insertions BTeV-GTeV interaction Plan: Now ... Form working groups and interested groups Expression of Interest to PAC April 2nd Workshop at Fermilab May 20-22nd Probably “Collaboration Mtg.” ~ September Proposal to PAC Fall 2004 Critical path probably High Field Dipoles

  40. Six random days of relevant preprints Theory76 Expt data3 Expt reviews2 So much theory So little experiment  UNHEALTHY

  41. Imagination is more important than knowledge. Einstein A Few of the Subjects not Covered p  3 jet fragmentation Fractal structure of jets Spikes in y-distributions Baryonium, cubic hadrons, buckyballs 2 leading n’s  pi-pi collider Color flow studies Multiple minijets & hot spots Color transparency QCD strings and superstrings strong interaction  gravity duality Hyperon (& pair) polarizations Elastic scattering: Coulomb – Large t Events with extreme K/pi, D/pi, … Skyrmions, chiral instantons Coherent pion emission Diffractive structure functions (various) QCD instantons udscbg Gluon condensates Color glass condensates Cosmic ray connection JGXGJ (X low mass) Centauro & Anticentauro Vacuum domains: very soft gammas Disoriented chiral condensates Chiral symmetry restoration Gamma-gamma ints, and L, sigma_inel Photoproduction, gamma-pom interference Odderon search Critical phenomena: wee quarks - pions Local Parton Hadron Duality etc, etc, etc !

  42. There is no higher or lower knowledge, but one only, flowing out of experimentation. Leonardo da Vinci

  43. My advice is to go for the messes – that’s where the action is. Steven Weinberg Address to Science Convocation, McGill University, 2003

  44. We do basic research to understand. And many times that’s justification enough. Spencer Abraham, Sec. of Energy 10th Nov 2003

  45. Concluding Remarks There will be a vast amount of QCD physics still to be done in 2009. Here I have only scratched the surface. One can easily imagine 20-30 publications / year Students, theses, training on collider physics close to home. The CDF and D0 detectors are great central detectors for this program, suitably upgraded at modest cost: DAQ, trigger, forward (few deg) and very forward (pots) Not all 1300 physicists on CDF and D0 want to go to LHC + from HERA, RHIC, JLab etc. Tevatron running anyway for BTeV, cost ~ $30M/year. Incremental cost of GTeV ~ $4M/year. Let’s do it!

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