Quarkonia and heavy-quark production in proton and nuclear collisions at the LHC

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Scattering Cold Nuclear Matter Effects Quark Gluon Plasma Signatures New

1 Quarkonia and heavy-quark production in proton and nuclear collisions at the LHC Michael Schmelling / MPI for Nuclear Physics Introduction Double Parton Scattering Cold Nuclear Matter Effects Quark Gluon Plasma Signatures New Developments Summary Heavy Quark Production at the LHC M. Schmelling, EDS Blois 215, Borgo, Corsica 1

2 1. INRODUCION theoretical understanding strong interactions: the QCD Lagrangian is well known and tested many open questions in the non-perturbative regime soft processes and bound states Quark Gluon Plasma - high densities and temperatures experimental approach: study heavy flavour production in: : : Heavy Quark Production at the LHC - Introduction M. Schmelling, EDS Blois 215, Borgo, Corsica 2

Angular coverage of the LHC experiments ALICE

acceptance Heavy Quark Production at the LHC

3 Angular coverage of the LHC experiments ALICE central forward muon coverage ALAS & CMS central detectors forward detector tracking, particle-id and calorimetry in full acceptance Heavy Quark Production at the LHC - Introduction M. Schmelling, EDS Blois 215, Borgo, Corsica 3

4 2. DOUBLE PARON SCAERING heavy flavours probe multi-parton interactions in pp collisions heavy flavours are suppressed in the inital state at LHC energies small-x partons are above the charm threshold, i.e. multi-parton interactions are expected to become important experimental signals: associated production of heavy particles J = plus W, Z or open charm double open charm production CC production from double-parton interactions C C production from single- and double parton interactions competition to multi-parton interactions: g! cc published results: ALAS JHEP 4(214)172 J = + W EPJC 75(215)229 J = + Z CMS JHEP 9(214)94 double J = PLB 77(212)52 double J = JHEP 6(212)141 double charm with open charm Heavy Quark Production at the LHC - Double Parton Scattering M. Schmelling, EDS Blois 215, Borgo, Corsica 4

5 double charm signals D D D D + D D + s D + c JHEP6(212)141 heuristic ansatz for double parton cross-sections DPS (C 1 C 2 ) = (C 1) (C 2 ) k eff with ( k = 2 for C1 = C 2 k = 1 for C 1 6= C 2 naive expectation eff inel ; CDF results suggest eff 15 mb Heavy Quark Production at the LHC - Double Parton Scattering M. Schmelling, EDS Blois 215, Borgo, Corsica 5

6 Evidence for multi-parton scattering double charm cross-sections normalization eff 355 pb pb 1 JHEP6(212)141 theoretical predictions underestimate J = C cross-sections CDF-DPS cross-sections seen in J = C cross-sections C C dominated by single parton scattering eff not needed CC has eff inel Heavy Quark Production at the LHC - Double Parton Scattering M. Schmelling, EDS Blois 215, Borgo, Corsica 6

7 Kinematic studies transverse momentum spectra in J = p (J = ) C -events p (open charm) 355 pb pb 1 JHEP6(212)141 harder p -spectrum for J = than for open charm quantitative analysis: fit an exponential slope for 3 < p < 12 GeV/c d dp / exp (s p ) systematic study of all event classes Heavy Quark Production at the LHC - Double Parton Scattering M. Schmelling, EDS Blois 215, Borgo, Corsica 7

8 Results 355 pb 1 experimental findings: JHEP6(212)141 soft spectra for prompt production harder spectra for CC & C C pattern for J = C : hard spectrum for J = soft spectrum for open charm consistent with DPS with a hard scattering producing the J = and a softer process producing open charm <= soft : : : : : :hard spectrum => Heavy Quark Production at the LHC - Double Parton Scattering M. Schmelling, EDS Blois 215, Borgo, Corsica 8

3. COLD NUCLEAR MAER EFFECS measure J = and production in pa and compare to pp pa collisions are an ideal laboratory to probe cold nuclear effects, e.g.

9 3. COLD NUCLEAR MAER EFFECS measure J = and production in pa and compare to pp pa collisions are an ideal laboratory to probe cold nuclear effects, e.g. parton shadowing as parameterized in nuclear PDFs (coherent) energy loss needed for the interpretation of QGP signatures in heavy-ion collisions use quarkonium states (J = ; ) to probe the hadronic environment combine information to disentangle shadowing and energy loss e.g. differentiate between prompt J = and J = from b Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 9

2345 currently still large unexplored regions combining J = ; and Z data from

10 Current knowledge of nuclear PDFs ratios of nucleon PDFs: F N (Pb)=F N (free) valence quarks gluons arxiv: currently still large unexplored regions combining J = ; and Z data from ALAS/CMS/ALICE/ allows to probe 1 6 < x < 1: Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 1

11 Observables sensitive to nuclear effects ratios: nuclear modification factor: forward-backward asymmetry: R pa (y) = 1 A d pa=dy d pp =dy R FB (y) = R pa(+jyj) R pa ( jyj) positive (forward) rapidity in direction of the proton pp cross-section cancels in R FB asymmetric detectors & swap of beam directions: access to forward and backward hemispheres published results: experiment J = production production ALICE JHEP 2(214)73 PLB 74(215)15 ALAS arxiv:155:8141 CMS JHEP 4(214)13 JHEP 2(214)72 JHEP 7(214)94 Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 11

12 Inclusive single differential J = cross-sections comparison of ALICE and (µb) dσ/dy p-pb s NN = 5.2 ev, inclusive J/ψ µ + µ (µb/(gev/c)) p-pb s NN = 5.2 ev, inclusive J/ψ µ + µ ALICE: 2.3<y <3.53, (preliminary) cms : 2.<y <3.5, arxiv: cms 6 4 σ/dydp 2 d 1 2 ALICE: <p <15 GeV/c, (arxiv: ) : <p <14 GeV/c, (arxiv: ) y cms p (GeV/c) ALICE-PUBLIC-213-2, -CONF slightly different kinematics agreement within uncertainties slightly harder p spectra for J = from b (not shown) Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 12

13 Results: nuclear modification factors common forward & backward acceptance: 2:5 < jy j < 4: prompt J = J = from b R ppb (a) ppb s NN = 5 ev EPS9 LO EPS9 NLO ndsg LO E. loss E. loss + EPS9 NLO, Prompt J/ψ p < 14 GeV/c y R ppb (b) ppb s NN = 5 ev EPS9 LO ndsg LO, J/ψ from b p < 14 GeV/c 1.6 nb nb y JHEP2(214)72 results require interpolation of pp cross-section to p s = 5 ev R ppb 6= 1: the nucleus is not a loose collection of independent nucleons tighter bound B-mesons less affected than prompt J = energy loss and shadowing are about equally important J = data agree with energy loss + NLO shadowing Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 13

14 Comparison of ALICE and comparison of inclusive J = R ppb p-pb s NN = 5.2 ev, inclusive J/ψ µ + µ measurements R FB p-pb s NN = 5.2 ev, inclusive J/ψ µ + µ.4.2 ALICE: <p <15 GeV/c, (arxiv: ) : <p <14 GeV/c, (arxiv: ) y cms.4 ALICE: 2.96< y <3.53, (arxiv: ).2 : 2.5< y cms cms <4, (arxiv: ) p (GeV/c) ALICE-PUBLIC-213-2, -CONF nuclear modification factor good agreement within uncertainties forward-backward asymmetry no need of pp reference cross-section stronger suppression at small p due to Cronin-effect, energy loss, : : : Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 14

15 Central Measurements ALAS measurement of prompt and non-prompt J = production BR(J/ψ µµ) [nb/gev] dy* σ /dp 2 1 ALAS p+pb, 28.1 nb 8 s NN = 5.2 ev < p < 3 GeV Prompt J/ψ Nonprompt J/ψ R FB 1.6 ALAS p+pb, 28.1 nb 1.4 s NN = 5.2 ev Prompt J/ψ y* < 1.94 Data EPS9 NLO (arxiv: ) arxiv: d y* p [GeV] no significant p dependence at large transverse momenta consistent with theoretical expectations similar observations for prompt and non-prompt J = s (not shown) study heavier systems : : : Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 15

16 Upsilon production in pa collisions statistics limited measurement 2 Candidates per 6 MeV/c ppb s NN = 5 ev < y < 4. p < 15 GeV/c 6 5. < y < 2.5 p < 15 GeV/c 1.6 nb nb m µ [MeV/c ] µ - 2 Candidates per 6 MeV/c ppb s NN = 5 ev m µ [MeV/c ] µ - JHEP7(214)94 no differential measurements possible kinematic range: p < 15 GeV/c, 1:5 < y < 4: and 5: < y < 2:5 study nuclear effects in common rapidity range 2:5 < jyj < 4: indication of suppression of (2S ) and (3S ) focus on (1S ) Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 16

17 Results on (1S ) production nuclear modification factor and forward-backward asymmetry R ppb E.loss+EPS9 NLO in Ref.[3] Υ(1S) Prompt J/ψ ppb s = 5 ev NN y R FB ppb s = 5 ev NN E.loss+EPS9 NLO in Ref.[3] 1.6 nb nb 1 Υ(1S) Prompt J/ψ y JHEP7(214)94 compare (1S ), J = from b and prompt J = large uncertainties less suppression for Upsilon production backward data consistent with expectations of anti-shadowing Upsilon consistent with J = from b Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 17

18 Comparison of ALICE and nuclear modification factor, fwd-bwd asymmetry & cross-section R ppb 1.4 p-pb s NN + - = 5.2 ev, inclusive ϒ(1S) µ µ R FB 1.4 p-pb s NN + - = 5.2 ev, inclusive ϒ(1S) µ µ 1.2 ALICE 1.2 ALICE ALICE-PUBLIC-214-2, -CONF (µb) dσ /dy y cms p-pb s NN + - = 5.2 ev, inclusive ϒ(1S) µ µ ALICE y cms agreement within uncertainties data dominated by statistics more data needed! y cms Heavy Quark Production at the LHC - Cold Nuclear Matter Effects M. Schmelling, EDS Blois 215, Borgo, Corsica 18

19 4. QUARK GLUON PLASMA SIGNAURES quarkonia as probes of the nuclear medium probe colour screening and QGP temperature through sequential melting of quarkonium states sensitivity to hot and cold nuclear matter effects test as many states as possible expect excited states to melt earlier expect charm to melt earlier than beauty published results: ALICE PRL 19(212)7231 J = suppression CMS PRL 17(211)5232 suppression of excites states PRL 19(212)22231 sequential suppression PRL 113(214)26231 (2S )=J = Heavy Quark Production at the LHC - Quark Gluon Plasma Signatures M. Schmelling, EDS Blois 215, Borgo, Corsica 19

20 ) Suppression of excited states compare central production in PbPb and pp 2 Events / (.1 GeV/c data PbPb fit pp shape µ p > 4 GeV/c CMS PbPb = 2.76 ev s NN Cent. -1%, y < L int = 15 µb R AA 1.4 CMS PbPb = 2.76 ev % s NN ϒ(1S), stat. unc. ϒ(1S), syst. unc. ϒ(2S), stat. unc. ϒ(2S), syst. unc. 4-5% 3-4% 2-3% -1 L int = 15 µb y < 2.4 µ p > 4 GeV/c 1-2% 5-1% -5% PRL19(212) Mass(µ + µ ) [GeV/c ] N part strong suppression of higher states more suppression in more central collisions larger suppression than in pa - also for (1S ) Heavy Quark Production at the LHC - Quark Gluon Plasma Signatures M. Schmelling, EDS Blois 215, Borgo, Corsica 2

21 Suppression of J = production measurement in forward region PRL 19(212)7231 R 1 (AA) AA = N part (pp) suppression by colour screening (?) extra production by recombination of c and c quarks (?) note: main effect at peripheral collisions accessible by plans to study AA and to extend the measurement to c Heavy Quark Production at the LHC - Quark Gluon Plasma Signatures M. Schmelling, EDS Blois 215, Borgo, Corsica 21

$114 m from IP central region not covered gap size 2 < < 8 huge gain for diffractive physics and central exclusive$ production (e.g.

22 5. NEW DEVELOPMENS HeRSCheL: High Rapidity Shower Counters for forward scintillators for selecting rapidity gaps up to 114 m from IP central region not covered gap size 2 < < 8 huge gain for diffractive physics and central exclusive production (e.g. J = photoproduction on the proton in pa) p > :5 GeV/c p > 1:5 GeV/c simulation results for the efficiency to see charged pions Heavy Quark Production at the LHC - New Developments M. Schmelling, EDS Blois 215, Borgo, Corsica 22

23 Fixed target physics with Ü SMOG: System for Measuring Overlap with Gas possibility to inject (noble) gases: Ne or He, Ar, Kr (under discussion) fixed target physics in pa and PbA configuration Heavy Quark Production at the LHC - New Developments M. Schmelling, EDS Blois 215, Borgo, Corsica 23

24 Nucleus-nucleus interactions first look at PbNe collisions using data from O(1) min running entries/(1 MeV/c 2 ) preliminary PbNe-interactions - work in progress KS m(π + π - ) [MeV/c 2 ] entries/(.5 MeV/c 2 ) s NN =54.4 GeV preliminary work in progress physics potential: explore nuclear structure at large x conditions between SPS and RHIC for QGP studies Λ,Λ m(pπ -,pπ + )[MeV/c 2 ] Heavy Quark Production at the LHC - New Developments M. Schmelling, EDS Blois 215, Borgo, Corsica 24

Links to other communities cosmic ray physics and cosmology understanding of extensive air showers MC tuning understanding the AMS antiproton/proton ratio use fixed

25 Links to other communities cosmic ray physics and cosmology understanding of extensive air showers MC tuning understanding the AMS antiproton/proton ratio use fixed target measurements to clarify: QCD or Dark Matter annihilation Heavy Quark Production at the LHC - New Developments M. Schmelling, EDS Blois 215, Borgo, Corsica 25

26 6. SUMMARY much has been learned from heavy quarks in pp, pa and AA many aspects of heavy flavour production not discussed e.g.: top, beauty and charm cross-sections ( talk by Marcin) polarization of quarkonium states central exclusive production double heavy-particle production probes multi-parton interactions qualitative understanding is emerging cold nuclear matter effects are being probed by pa collisions important constraints on nuclear PDFs, but more data are needed evidence for QGP is seen from Upsilon melting very convincing signals but no quantitative description yet bright prospects for LHC RunII more data to address open points higher energies to get additional constraints new developments further enlarge the physics program much still remains to be learned : : : Heavy Quark Production at the LHC - Summary M. Schmelling, EDS Blois 215, Borgo, Corsica 26

Diffraction Physics at LHCb

$Diffraction Physics at LHCb$ Diffraction Physics at LHCb Michael Schmelling LHCb / MPI for Nuclear Physics The LHCb Experiment Energy Flow Central Exclusive Production New Developments Summary Diffraction Physis at LHCb M. Schmelling,