New high resolution measurements of open and hidden charm production in proton-nucleus collisions at s = 110 GeV with LHCb

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Quark Matter, 7th February 217 1/17 Open

1 LHCb SMOG par Analysis par Results Conclusion New high resolution measurements of open and hidden charm production in protonnucleus collisions at s = 11 GeV with LHCb E milie Maurice on behalf of the LHCb collaboration XXVI international conference on ultrarelativistic heavyion collisions, Quark Matter, 7th February 217 1/17 Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR)

LHCb SMOG par Analysis par Results Conclusion Fixed target protonnucleus program at LHCb LHCb designed for b, c physics; general purpose detector in the forward direction Unique oppportunity to

2 LHCb SMOG par Analysis par Results Conclusion Fixed target protonnucleus program at LHCb LHCb designed for b, c physics; general purpose detector in the forward direction Unique oppportunity to perform fixedtarget mode program at LHC: Forward measurement of open and hidden charm production (J/ψ, D...) Measurement down to low p Large rapidity coverage ( 3 rapidity units) at large Bjorkenx Access to npdf antishadowing region Access to intrinsic charm content in the nucleon Protonnucleus collisions provide reference for heavy ions studies Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 2/17

3 LHCb SMOG par Analysis par Results Conclusion LHCb detector Single arm spectrometer in the forward region, fully instrumented in 2 < η < 5 LHCb can operate in fixedtarget mode Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 3/17

4 LHCb SMOG par Analysis par Results Conclusion LHCb SMOG SMOG: System for Measuring Overlap with Gas Injecting noble gas (He, Ne, Ar,...) in the Vertex Detector Primary role: beamgas imaging for luminosity measurement Can be used as an internal gas target ( 1 7 mbar) Fixedtarget mode Parasitic to the collider mode Gas spreads in the beam pipe up to ±2m around LHCb Use noncolliding bunches Fixedtarget specs With 2.5 to 7 ev proton beams: snn [69, 115] GeV With 2.5 ev Pb beams: snn = 69 GeV Backward rapidity region y = y 4.77 Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 4/17

5 LHCb SMOG par Analysis par Results Conclusion LHCb fixedtarget mode: par analysis Study the J/ψ and D production in par collisions at = 11 GeV in rapidity and transverse momentum bins LHCbCONF2171 First measurement of heavyflavour production with LHCb in fixedtarget mode 6.5 ev proton beam on argon gaseous target 1 7 mbar During 17h, protons on target Reconstructed collision vertices extended over 1m Primary Vertex R position (mm) s = 11 GeV par Data Primary Vertex Z position (mm) Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 5/17

6 LHCb SMOG par Analysis par Results Conclusion Signal extraction Select events with Z vertex inside the Vertex Detector, Z vertex [ 2, +2] mm J/ψ and D signal are extracted using Crystal Ball functions Candidates / (1 MeV/ = 11 GeV par N J/ψ = 482 ± 23 Candidates / (5 MeV/ σ 14 MeV/c 2 σ 8 MeV/c = 11 GeV par N D = 6451 ± m(µ + µ ) [MeV/c 2 ] m(k π + ) [MeV/c 2 ] 5 J/ψ µ + µ 6 5 D K π ± Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 6/17

7 LHCb SMOG par Analysis par Results Conclusion N D N D N D N D Differential production: rapidity J/ψ and D signal extracted independently in 4 rapidity bins y [2, 3] y [3, 3.5] y [3.5, 4] y [4, 4.6] J/ψ Candidates / (1 MeV/ = 11 GeV par N J/ψ = 73 ± 9 y [2, 3] Candidates / (1 MeV/ = 11 GeV par N J/ψ = 142 ± 12 y [3, 3.5] Candidates / (1 MeV/ = 11 GeV par N J/ψ = 168 ± 13 y [3.5, 4] Candidates / (1 MeV/ = 11 GeV par N J/ψ = 13 ± 1 y [4, 4.6] m(µ + µ ) [MeV/c 2 ] m(µ + µ ) [MeV/c 2 ] m(µ + µ ) [MeV/c 2 ] m(µ + µ ) [MeV/c 2 ] D Candidates / (5 MeV/ = 11 GeV par = 765 ± 29 y [2, 3] Candidates / (5 MeV/ = 11 GeV par = 1918 ± 49 y [3, 3.5] Candidates / (5 MeV/ = 11 GeV par = 2433 ± 56 y [3.5, 4] Candidates / (5 MeV/ = 11 GeV par = 146 ± 46 y [4, 4.6] m(k π ) [MeV/c 2 ] m(k π ) [MeV/c 2 ] m(k π ) [MeV/c 2 ] m(k π ) [MeV/c 2 ] Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 7/17

8 LHCb SMOG par Analysis par Results Conclusion N D N D N D N D Differential production: transverse momentum J/ψ and D signal extracted independently in 4 transverse momentum bins [,.6] GeV/c [.6, 1.2] GeV/c [1.2, 1.8] GeV/c [1.8, 8] GeV/c J/ψ Candidates / (1 MeV/ = 11 GeV par N J/ψ p = 59 ± 8 [,.6] GeV/c Candidates / (1 MeV/ = 11 GeV par N J/ψ p = 155 ± 13 [.6, 1.2] GeV/c Candidates / (1 MeV/ = 11 GeV par N J/ψ p = 12 ± 11 [1.2, 1.8] GeV/c Candidates / (1 MeV/ = 11 GeV par N J/ψ p = 155 ± 12 [1.8, 8] GeV/c m(µ + µ ) [MeV/c 2 ] m(µ + µ ) [MeV/c 2 ] m(µ + µ ) [MeV/c 2 ] m(µ + µ ) [MeV/c 2 ] D Candidates / (5 MeV/ = 11 GeV par p = 1251 ± 42 [,.6] GeV/c Candidates / (5 MeV/ = 11 GeV par p = 1992 ± 51 [.6, 1.2] GeV/c Candidates / (5 MeV/ = 11 GeV par p = 1496 ± 42 [1.2, 1.8] GeV/c Candidates / (5 MeV/ = 11 GeV par p = 1736 ± 43 [1.8, 8] GeV/c m(k π ) [MeV/c 2 ] m(k π ) [MeV/c 2 ] m(k π ) [MeV/c 2 ] m(k π ) [MeV/c 2 ] Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 8/17

9 LHCb SMOG par Analysis par Results Conclusion Yield corrections and uncertainties N k = Nmeasured k ɛ k with k = J/ψ, D N measured k extracted from mass fits are corrected for different efficiencies: ɛ k = ɛ k acc ɛ k trig ɛ k sel ɛ k reco ɛ k PID geometrical acceptance, trigger, selection, reconstruction, particle identification Corrections are computed using par simulation samples and pp 13 ev data Source of uncertainties J/ψ y J/ψ p D y D p Corr. between bins Signal selection 1.4% 1.4% 2.2% 2.2% Signal extraction 2.3% 2.3% 2.3% 2.7% Uncorr. between bins MC sample ( )% (.9 1.4)% (1. 1.9)% (1. 1.5)% racking ( )% ( )% ( )% ( )% PID (.2 2.7)% (.1 2.)% ( )% ( )% Stat. uncertainties ( )% ( )% (.7 3.7)% (.6 3.4)% J/ψ uncertainties are dominated by statistical uncertainties Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 9/17

10 LHCb SMOG par Analysis par Results Conclusion J/ψ corrected yields Rapidity y ransverse momentum p /dy J/ψ = 11 GeV par J/ψ /dp = 11 GeV par Rapidity y ransverse momentum p [MeV/c] Blue points: data J/ψ dy, J/ψ dp Vertical lines: stat. uncertainties (black), uncorrelated syst. uncertainties (blue) Box: Quadratic sum of statistical, uncorrelated and correlated syst. uncertainties Red area: Monte Carlo (PYHIA8C9MCS/NRQCD) normalized to data, uncertainties are statistical Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 1/17

11 LHCb SMOG par Analysis par Results Conclusion J/ψ: comparison with phenomenological parametrizations Based on Arleo, F. & Peigné, S. J. High Energ. Phys. (213) 213: 122. Arleo, F. et al. J. High Energ. Phys. (213) 213: 155. Rapidity in cms: y = y 4.77 ransverse momentum p /dy* J/ψ = 11 GeV par J/ψ /dp = 11 GeV par Rapidity in centreofmass y* ransverse momentum p [MeV/c] Phenomenological parameters based on linear and logarithmic interpolations between 41.5 GeV and 2 GeV measurements No strong difference observed within uncertainties Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 11/17

12 LHCb SMOG par Analysis par Results Conclusion D corrected yields Rapidity y ransverse momentum p /dy D = 11 GeV par /dp D 25 2 = 11 GeV par Rapidity y ransverse momentum p [MeV/c] Blue points: data D dy, D dp Vertical lines: stat. uncertainties (black), uncorrelated syst. uncertainties (blue) Box: Quadratic sum of statistical, uncorrelated and correlated syst. uncertainties Red area: Monte Carlo (PYHIA8C9MCS) normalized to data, uncertainties are statistical Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 12/17

13 LHCb SMOG par Analysis par Results Conclusion Bjorkenx distribution x 2 = M snn exp( y ) J/ψ D /dx 2 J/ψ = 11 GeV par /dx 2 D = 11 GeV par M J/ψ x 2 = exp(y*) 15 = x 2 M D exp(y*) Bjorkenx x Bjorkenx x 2 Coverage: x J/ψ 2 [.3,.45] x2 D [.2,.27] Blue points: data Vertical lines: stat. uncertainties (black), uncorrelated syst. uncertainties (blue) Box: Quadratic sum of statistical, uncorrelated and correlated syst. uncertainties Red area: Monte Carlo (PYHIA8C9MCS) normalized to data, uncertainties are statistical Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 13/17

14 LHCb SMOG par Analysis par Results Conclusion Feynmanx distribution x F = x 1 x 2 = 2 M snn sinh(y ) J/ψ D J/ψ /dx F = 11 GeV par M J/ψ x F = 2 sinh(y*) /dx F D = 2 x F = 11 GeV par M D sinh(y*) Coverage: Feynmanx x F x J/ψ F [.45,.1] xf D Feynmanx x F [.27,.1] Blue points: data Vertical lines: stat. uncertainties (black), uncorrelated syst. uncertainties (blue) Box: Quadratic sum of statistical, uncorrelated and correlated syst. uncertainties Red area: Monte Carlo (PYHIA8C9MCS) normalized to data, uncertainties are statistical Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 14/17

15 LHCb SMOG par Analysis par Results Conclusion Comparison between J/ψ and D cross sections σ(j/ψ) σ(d ) = NJ/ψ N D BR(D K π ± ) BR(J/ψ µ + µ ) ) σ(j/ψ) / σ(d = 11 GeV par Rapidity y No strong difference observed between J/ψ and D production Looking for theoretical predictions Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 15/17

16 LHCb SMOG par Analysis par Results Conclusion High resolution performance also for D +, D +, D + s, Λ + c Candidates / (4 MeV/ s = 11 GeV par + D K π + π Candidates / (2.67 MeV/ s = 11 GeV par *+ D D π m(k π π ) [MeV/c 2 ] m(d π + ) [MeV/c 2 ] Candidates / (6.4 MeV/ s = 11 GeV par + + Ds K K π + Candidates / (6.4 MeV/ s = 11 GeV par + Λ p K π + c m( K K π + ) [MeV/c 2 ] m(p K π + ) [MeV/c 2 ] Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 16/17

17 LHCb SMOG par Analysis par Results Conclusion Conclusion First measurement of heavyflavour production in LHCb fixedtarget mode Studied J/ψ and D production in par collisions at s = 11 GeV Collected after selection overall 5 J/ψ and 65 D LHCb is able to access npdf antishadowing region and intrinsic charm content in the nucleon Observe no strong difference between J/ψ and D production LHCb can also: Measure D +, D +, D + s, Λ + c hadrons Perform analysis of ψ(2s), χ c with future larger data samples Outlook: Work on luminosity for crosssection measurements Investigate phe, pne, PbAr data ake additional fixedtarget data in 217 Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 17/17

18 LHCb SMOG par Analysis par Results Conclusion Back up Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 18/17

19 LHCb SMOG par Analysis par Results Conclusion SMOG data taking 215: phe: 8h, = 11 GeV, protons on target pne: 2h, = 11 GeV, protons on target par: 18h, = 11 GeV, protons on target par: 11h, = 69 GeV, protons on target PbAr: 1h, = 69 GeV, nuclei on target : phe: 18h, = 11 GeV, protons on target phe: 87h, = 87 GeV, protons on target Open and hidden charm production in par at s = 11 GeV, with LHCb, E. Maurice (LAL, LLR) 19/17

Heavy ion physics at LHCb

Heavy ion physics at LHCb J/ψ in ppb, 8 ev D in ppb, 5 ev Λ+ c in ppb, 5 ev Heavy flavour with SMOG data Conclusion Heavy ion physics at E milie Maurice on behalf of the collaboration ICFNP 25th August 217, Kolymbari, Creta August