Production & Spectroscopy Production & Spectroscopy of Heavy Hadrons of Heavy Hadrons at the LHC at the LHC Hal Evans Indiana University for the ALICE, ATLAS, CMS, LHCb Collaborations Hadron2011, 13-17 June, 2011, Munich Hadron2011: 16 June, 2011 1 Hal Evans
Outline Outline Outline Outline 1) Overview of LHC Experiments – Issues relevant for heavy hadrons 2) Heavy Flavor Production – Background & Theoretical predictions – Charm production – Beauty production 3) Exclusive Final States – Spectroscopy – Tool for studying Electro-Weak symmetry breaking 4) Summary of What We’ve Learned (so far) – What to look for in the future ~50 Experimental Results from ALICE, ATLAS, CMS, LHCb ~50 Experimental Results from ALICE, ATLAS, CMS, LHCb Hadron2011: 16 June, 2011 2 Hal Evans
What I Won’t Cover What I Won’t Cover What I Won’t Cover What I Won’t Cover Tragically, the organizers ignored my request for more time – and I only needed 150 extra minutes ! We will have to skip – nearly interesting experimental details – many states that have been re-observed at the LHC – CP-violation and other electro-weak topics – B → μ + μ − – top physics (feeble excuse: it doesn’t hadronize) Other LHC Heavy Flavor-related talks at Hadron 2011 – Plenary Sessions > Charmonium (Yuanming Gao) & Bottomonium (Nuno Leonardo) – Parallel Session talks by > ALICE: K. Schweda, F. Kramer > ATLAS: C. Schiavi > CMS: B. Akgun, B. Paolo, H-C Kaestli, C. Grab, J. Wang > LHCb: R. Cardinale, G. Sabatino, A. Uklega, B. Liu Hadron2011: 16 June, 2011 3 Hal Evans
Heavy Flavors and LHC Exp’s Heavy Flavors and LHC Exp’s Heavy Flavors and LHC Exp’s Heavy Flavors and LHC Exp’s Heavy Flavor Production/Spectroscopy is not the primary focus of any of the LHC experiments – ATLAS/CMS direct searches for new physics – LHCb matter-antimatter asymmetry, EW symmetry breaking – ALICE strongly interacting matter at extreme energy densities Nevertheless each has good capabilities to make these types of measurements – unfortunately, no time to go into details of each experiment – but will highlight a few of the most important issues Hadron2011: 16 June, 2011 4 Hal Evans
Experimental Issues Illustrated Experimental Issues Illustrated Experimental Issues Illustrated Experimental Issues Illustrated B s → μ D s X Event at LHCb General Experimental Concerns – production & acceptance – triggering – tracking: vertexing, mass – particle ID: leptons, hadrons Hadron2011: 16 June, 2011 5 Hal Evans
Production and Acceptance Production and Acceptance Production and Acceptance Production and Acceptance Data Collected Detector Acceptances – all exp’s efficiency > 90% pp Luminosity 2010 2011 μ e ALICE peak (cm –2 s −1 ) 2∙10 32 >1∙10 33 ATLAS μ integrated (pb −1 ) ~40 >1000 μ CMS (>350 LHCb) LHCb Triggers used in analyses Trigger Exp’s Comments min(micro) bias all only earliest data single muon all lowest p T prescaled single jet ATLAS, CMS lowest p T prescaled di-muon all unprescaled (so far) displaced Vtx LHCb unprescaled Hadron2011: 16 June, 2011 6 Hal Evans
Tracking & Hadron ID Tracking & Hadron ID Tracking & Hadron ID Tracking & Hadron ID Mass Resolution π/K/p Separation – all exp’s have some capabilites > but not used here by ATLAS,CMS,ALICE – LHCb (RICH) used extensively Impact Parameter Resolution track ALICE ~30 μm p T = 8 GeV impact ATLAS ~30 μm p T = 5 GeV param CMS ~30 μm p T = 6 GeV LHCb ~30 μm high p T primary vertex Hadron2011: 16 June, 2011 7 Hal Evans
Heavy Flavor Production Heavy Flavor Production Heavy Flavor Production Heavy Flavor Production D Q H (z) A f a (x 1 ) Q ̂ σ ab Q Hard Interaction B f b (x 2 ) Parton Shower / Fragmentation Incoming Particles PDFs d σ( pp → X ) = ∑ a ,b ∫ dx a dx b dz Fragmentation Function f a ( x 1, μ F ) f b ( x 2, μ F ) 3 p 1 ... d 3 p n d H ( z , μ F ' ) ̂ × σ ab ( p a , p b , p X , α s (μ R ) , μ R , μ F ) × D Q Hard Scatter x-sect renormalization & factorization scales Hadron2011: 16 June, 2011 8 Hal Evans
Situation c. 2000 Situation c. 2000 Situation c. 2000 Situation c. 2000 D* production in DIS (ZEUS) CDF, D0 Run I arXiv:hep-ph/0201071 Beauty Production vs NLO predictions – reasonable agreement in shape, but scale off by factors of 2–3 Charm Production vs NLO Predictions – agreement generally better, but errors quite large Could this be New Physics ??? Hadron2011: 16 June, 2011 9 Hal Evans
Road to Enlightenment Road to Enlightenment Road to Enlightenment Road to Enlightenment Experimental Issues: be careful what you report – cross-sections from reconstructed b -hadrons (B + → J/ψ K + , ...) > careful treatment of fragmentation, updated α s & PDFs – cross-sections from b- tagged jets Theory Issues: consistent calculations peripheral to NLO – Large scale dependence: sizable contributions from beyond NLO > low p T small x ~ m b / √ s effects > high p T large log( p T / m b ) (FONLL resummation) – Consistent (FONLL) treatment of fragmentation functions ) 9 0 9 0 0 2 y ( t u 9 a 7 e D B R : s P t t : i F P D . K C Hadron2011: 16 June, 2011 10 Hal Evans
State of the Art State of the Art State of the Art State of the Art Heavy Flavor Production included in MC generators – PYTHIA, HERWIG: LO with some higher order topologies NLO: Flavor Excitation NLO: Gluon Splitting LO: Flavor Creation – MadGraph/MadEvent: 2 → 2,3 Processes – CASCADE: off-shell LO Matrix Elems w/ high-E factorization – MC@NLO, POWHEG, FONLL,MCFM: full NLO calculations Experimental Issues – Does good data vs NLO agreement extend to new LHC energy regime? – How well do we understand the details of higher order topologies? – Cross-section measurements techniques > i) inclusive ( b/c -jet, e/μ) ii) partially inclusive (μ D 0 X, J/ψ X,...) > iii) exclusive ( c →D (*) , B + → J/ψ K + ,...) Hadron2011: 16 June, 2011 11 Hal Evans
Exclusive c c : LHCb : LHCb Exclusive Exclusive c c : LHCb : LHCb Exclusive pp → D X using micro bias trigger (1.81 nb −1 – May, 2010) – b -component extract using fit to D-meson impact parameter distrib. D *+ → D 0 (K − π + ) π + D 0 → K − π + D + → K − π + π + 3 1 0 - 0 1 0 2 - F N PYTHIA O D s + → Φ(K − K + ) π + MC: Cacciari, Frixione, Mangano, Nason, Ridolfi C - BAK: Kniehl, Kramer, Schienbein, Spiesberger B C H L Hadron2011: 16 June, 2011 12 Hal Evans
Exclusive c c : ATLAS : ATLAS Exclusive Exclusive c c : ATLAS : ATLAS Exclusive pp → D X using minimum bias trigger (1.1 nb −1 – Mar-Jul, 2010) – contains both b,c components (nb: σ cc ~ 20 σ bb ) D *+ → D 0 (K − π + ) π + D *+ → D 0 (K − π + ) π + D + → K − π + π + D s + → Φ(K − K + ) π + N (D s ± ) = 304 ± 51 N (D *± ) = 2310 ± 130 N (D ± ) = 1546 ± 81 ATLAS-CONF-2011-017 vis [μ b ] σ ( p T > 3.5 GeV, ∣η∣< 2.1 ) POWHEG-PYTHIA ∗± + 32 ( syst ) ± 31 ( lum ) ± 4 ( br ) + 169 ( scale ) + 13 ( m Q ) + 24 ( PDF ) + 20 ( hadr ) D 285 ± 16 ( stat ) 153 − 27 − 80 − 15 − 21 − 16 ± + 35 ( syst ) ± 26 ( lum ) ± 10 ( br ) + 137 ( scale ) + 11 ( m Q ) + 20 ( PDF ) + 21 ( hadr ) D 238 ± 13 ( stat ) 132 − 23 − 65 − 10 − 18 − 11 ± + 27 ( syst ) ± 18 ( lum ) ± 10 ( br ) + 57 ( scale ) + 4 ( m Q ) + 9 ( PDF ) + 7 ( hadr ) D s 168 ± 34 ( stat ) 59 − 25 − 28 − 6 − 8 − 8 ● data already systematics limited ● data already systematics limited ● results agreement with NLO predictions within large uncertainties ● results agreement with NLO predictions within large uncertainties Hadron2011: 16 June, 2011 13 Hal Evans
Exclusive c c : ALICE : ALICE Exclusive Exclusive c c : ALICE : ALICE Exclusive pp → D X at √s = 7 TeV: 1.6 nb −1 (20% of 2010 data) D + → K − π + π + D 0 → K − π + D *+ → D 0 (K − π + ) π + FONLL: Cacciari et al. GM-VFNS: Kniehl et al. ● y acceptance is p T dependent ● y acceptance is p T dependent (Δ y ~ 1.0 – 1.6) (Δ y ~ 1.0 – 1.6) also pp → D X at √s = 2.76 TeV: 1.1 nb −1 ● results scaled to Δ y = 0.5 ● results scaled to Δ y = 0.5 – 3 days of data! ● results in good agreement with ● results in good agreement with NLO predictions NLO predictions Hadron2011: 16 June, 2011 14 Hal Evans
Charm Summary Charm Summary Charm Summary Charm Summary Differential cross-sections within exp acceptances – generally reasonable agreement: data vs NLO – but large uncertainties Extrapolate individual measurements to full phase space – theory extrapolation error (ATLAS, ALICE) dominates all others LHCb PYTHIA ATLAS POWHEG-PYTHIA ALICE FONLL Hadron2011: 16 June, 2011 15 Hal Evans
Inclusive b b : 3 Methods : 3 Methods Inclusive Inclusive b b : 3 Methods : 3 Methods Inclusive p T rel p T rel Method p T rel Method Vertex Method jet Vertex Method L / σ μ jet vertex mass B large B-mass ● Data 2010 → large kick to B MC light jets decay muon MC c jets B MC b jets flight B M [GeV] length Inclusive Leptons Inclusive Leptons π 0 conv. of γ meson η ω Φ e,μ η’ ρ J/ψ Υ direct γ,γ * B BR (B→ℓν X ) ~ 11% B d Hadron2011: 16 June, 2011 16 Hal Evans ALI-PREL-3940
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