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Status of PPR Chapter 6.5 Charm and Beauty

Status of PPR Chapter 6.5 Charm and Beauty. Editors: F. Antinori 2 and A. Dainese 1,2 1 University and 2 INFN – Padova. Before moving to ~editorial matters… …The Latest News: “The charm of non-central collisions”.

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Status of PPR Chapter 6.5 Charm and Beauty

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  1. Status of PPR Chapter 6.5Charm and Beauty Editors: F. Antinori2 and A. Dainese1,2 1University and 2INFN – Padova ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  2. Before moving to ~editorial matters… …The Latest News: “The charm of non-central collisions” • This item is missing in 6.5, although important (need to know requested number of events for RCP & v2 studies… see physics motivations later on) • First steps: • Calculated heavy-quark yields as a function of centrality (using centrality classes as defined in PPR 6.1) • Estimated D0Kp performance in semi-periph. collisions (preliminary) • Goal: have something on D0 in the PPR, maybe something on B  e+X ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  3. Heavy quarks and dNch/dy vs centrality(PPR 6.1 classes) b-dependence of shadowing from Emel’yanov, Khodinov, Klein, Vogt, PRC61 (2000) 044904 ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  4. Heavy quarks and dNch/dy vs centrality (2) for v2 for RCP b-dependence of shadowing from Emel’yanov, Khodinov, Klein, Vogt, PRC61 (2000) 044904 ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  5. D0 Kp in 33-58% Pb-Pb (2.5x106 evts) • Used signal and background samples for Pb-Pb 0-5% • Rescaled signal by 0.11 (decrease of Ncc/event) • assumed same shadowing as in central collisions… • Rescaled backgr. by [(dNch/dy)33-58%/(dNch/dy)0-5%]2 ~ 0.01 • Assumed same tracking & PID efficiencies & resolutions as in central collisions • Issue: primary vertex reconstruction may be worse • xy: same resolution as in central, given by beam size • z: worse resolution sz(dNch/dy=600) = 15 mm (from Catania’s vertex reconstruction results) [sz(dNch/dy=6000) = 5 mm] • not a problem: z used only for pointing angle, where resolution dominated by secondary vertex z-res. ~ 80 mm • (roughly) Retuned cuts for new normalization ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  6. Rel. statistical error for 33-58% 33-58% Larger bins than for 0-5% have to be used 0-5% ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  7. pT distribution for 33-58% (0-5%) same systematic errors (band) as for 0-5% assumed ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  8. RCP for 0-5%/33-58% • only stat. errors (dominated by 33-58% errors, if RCP=1) • errors estimation for more likely RCP~0.4 in progress • systematic error should mainly come from <Ncoll> ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  9. pT bin (GeV/c) pT bin (GeV/c) Signal Signal sv2 (statistical) sv2 (statistical) 5-7 5-7 3x74 74 0.05 0.08 33-58% 2.5x106 evts 20-60% 4x106 evts 7-10 7-10 3x34 34 0.12 0.07 10-14 10-14 12 3x12 0.12 0.20 5-14 5-14 3x120 120 0.04 0.06 First look at v2(quick&dirty) • For pT < 5 GeV/c, candidate are signal + background need to study bkg v2 (e.g. using sidebands or ev. mixing) and subtract it requires dedicated study • For pT > 5 GeV/c, background is negligible just get v2 from all D0 candidates (only signal) • First trial, for pT > 5 GeV/c: assumed v2 ~ 0.10-0.20 Need more “non-central” events? ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  10. Back to editorial matters…Contents of chapter 6.5 • 6.5.1 Physics motivations • 6.5.2 Available measurements of heavy-flavour hadroproduction • 6.5.3 Charm and beauty production at LHC • 6.5.4 Exclusive charm reconstruction with D0 Kp • 6.5.5 Perspectives for the study of charm quenching • 6.5.6 Beauty detection in the semi-electronic decay channels ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  11. New sections to be added • 6.5.7 Beauty in the muon channels • Single and di- muons in Pb-Pb (by R. Guernane) • Presented as work in progress: • 3- and 4-muons in pp and pA (prel. study by A. Morsch) • e-m correlations (prel. study by P. Crochet) • 6.5.8pp-specific section: detection possibilities for nonlinear effects in gluon evolution via charm ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  12. 6.5.1 Physics Motivations • Heavy quarks: produced in early stage, hard scale, calculable in pQCD • Added pp and pA specific motivations: • test pQCD and factorization in pp/pA • look for break down of factorization: shadowing, gluon saturation, Color Glass Condensate • look for multiparton scattering in pA • Revised AA motivations. Heavy quarks can probe: • density of medium, via energy loss and its dependences (mass, colour charge) • degree of thermalization, via v2 ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  13. 6.5.1 Physics Motivations • Probing high-density initial state with heavy quarks • nonlinear gluon evolutions in pp • shadowing in pA (AA) • CGC in pA (AA) • Multiple parton scattering in pA ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  14. 6.5.1 Physics Motivations • Probing high-density initial state with heavy quarks • nonlinear gluon evolutions in pp • shadowing in pA (AA) • CGC in pA (AA) • Multiple parton scattering in pA • Saturation scale Qs2(x) ~ xg(x)A/RA2 ~ xg(x)A1/3 • At LHC for x~10-4, Qs~1-5-2 GeV > mc • For mT,c~Qs, charm prod. CGC-dominated: • scales with Npart in pA (not Ncoll) • harder pT spectra, since typical kT~Qs~1.5 GeV, while • in standard factorization kT~LQCD~0.2 GeV ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  15. predicted rate: cccc/cc ~ 10% (Treleani et al.) signature: events with “tagged” DD (can use D0+e+ or e+e+) and ch. conj. NB: there is a “background” from normal bb events, but is can be estimated from measured single inclusive b cross section 6.5.1 Physics Motivations • Probing high-density initial state with heavy quarks • nonlinear gluon evolutions in pp • shadowing in pA (AA) • CGC in pA (AA) • Multiple parton scattering in pA probe “many-body” PDFs normal and anomalous: different A dep. ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  16. mass effect 6.5.1 Physics Motivations • Medium effects in AA: • heavy-quark energy loss • azimuthal asymmetry / v2 / coalescence RD/h enhancement probes color-charge dep. of E loss RB/h enhancement probes mass dep. of E loss Armesto, Dainese, Salgado, Wiedemann, PRD71 (2005) 054027. ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  17. f = p/2 f = 0 6.5.1 Physics Motivations • Medium effects in AA: • heavy-quark energy loss • azimuthal asymmetry / v2 / coalescence RHIC 200 GeV • The azimuthal asymmetry (v2) of D and B • mesons in non-central collisions tests: • at low/moderate pT: coalescence scenario, v2 of c/b quarks, hence degree of thermalization of medium • at higher pT: path-length dependence of E loss (almond-shaped medium => v2~5-10%) Greco, Ko, Rapp, nucl-th/0312100 ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  18. 6.5.2 Available measurements • Not only pA and AA, included also ppbar (Tevatron) • pA: • Charm production in pA fixed target up to sqrt{s} ~ 40 GeV: understood and well described by binary scaling • AA: • The NA50 di-muons enhancement puzzle • Single electrons from PHENIX (RAA and v2) • Additions: • Charm and beauty in ppbar at 1.96 TeV (compared to FONLL calc.) • Charm in d-Au at 200 GeV: STAR D meaurement compared to FONLL calc. ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  19. 6.5.3 Production at LHC • Total cross sections at NLO in nucleon-nucleon collisions from MNR code with CTEQ5M and MRST2001 • Extrapolation to p-Pb and Pb-Pb collisions • Spectral shapes and tuning of event generators (PYTHIA) • Hadronization and decays • Being added: • figures with theoretical uncertainty bands from MNR and, optionally, FONLL • theoretical uncertainty for extrapolation of pp measurement from 14 TeV to 5.5 TeV ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  20. 6.5.3 Production at LHC 0.5 mt < mF,mR < 2 mt, 1.3 < mc < 1.7 GeV, 4.5 < mb < 5.0 GeV ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  21. 6.5.3 Production at LHC Extrapolation of the pp data from 14 to 5.5 TeV beauty 14/5.5 charm 14/5.5 +10/-15% syst. error +5/-10% syst. error 0.5 mt < mF,mR < 2 mt, 1.3 < mc < 1.7 GeV, 4.5 < mb < 5.0 GeV ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  22. 6.5.4 D0 Kp • D0 K-p+ analysis in central Pb-Pb (0-5%) • done for B = 0.4 T and dNch/dy = 6000 • extrapolation to lower multiplicity (3000) • extrapolation to lower field (0.2 T) • Same analysis in pp: focus on pp-specific problems, namely primary vertex uncertainty due to necessity to reduce luminosity at ALICE I.P. to ~1030 cm-2s-1 • Being included: p-Pb study by R. Grosso • Physics performance: • uncertainties in charm cross section measurement • energy loss studies: sensitivity to RAA and ratio D/hadrons ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  23. mc PDFs scales down to pt ~ 0 ! The Physics plots (1) • D0 cross section measurement ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  24. The Physics plots (2) • Charm quenching: sensitivity to D-meson suppression updated predictions Armesto, Dainese, Salgado, Wiedemann, PRD71 (2005) 054027 ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  25. Study shadowing in p-Pb at 8.8 TeV? (to be included) R.Grosso, PhD thesis (2004) ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  26. 6.5.6 B  e+X in Pb-Pb (complete study presented at ALICE Week in March) Using electrons in 2 < pt < 20 GeV/c obtain B meson 2 < ptmin < 30 GeV/c inner bars: stat. errors outer bars: stat.  pt-dep. syst. errors not shown: 11% normalization error Note: quenching curves mainly for illustration. Pb-Pb vs. pp comparison needed to study E loss Study of Be+X in pp is in progress in Padova ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  27. 6.5.7 Beauty with muons in Pb-Pb (still to be included, but ~ copy-paste from ALICE note) (Guernane et al.) ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  28. Summary • Ch 6.5 text in good shape: ~70 pages! • Received comments by Jurgen, Yiota, Luciano (thanks!) • We plan to still include: • D0 in p-Pb results • D0 performance in semi-peripheral Pb-Pb • D quenching studies • B m • possible non-linear effects in pp • a paragraph on future developments (other channels / physics observables) ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  29. EXTRAS ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  30. Results for 33-58% Not divided by bin width Larger bins than for 0-5% have to be used ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  31. S/B and Significance for 33-58% 33-58% 0-5% ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  32. 6.5.2 Available measurements CDF D-meson data at 1.96 TeV hep-ex/0307080 FONLL predictions by Cacciari and Nason ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  33. 6.5.2 Available measurements CDF B  J/ + X data at 1.96 TeV FONLL and MC@NLO predictions by Cacciari, Frixione, Mangano, Nason and Ridolfi, hep-ph/0312132 ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

  34. FONLL, hep-ph/0502203 6.5.2 Available measurements STAR D-meson data in d-Au at 200 GeV nucl-ex/0407006 nucl-ex/0404029 (high pt prelim.) ALICE Physics Forum - Utrecht, June 14, 2005 Andrea Dainese

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