PROTON STRUCTURE AND HARD P-P PROCESSES AT LHC ENERGIES LHC ATLAS Gennady Lykasov* in collaboration with Vadim Bednyakov *, Michail Demichev* Mark Stockton**, Tzvetalina Stavrveva***, Yuri Stepanenko* *JINR, Dubna, ** Mcgill Univ. & CERN ***LPSC, Grenoble, France 1 1

OUTLINE 1. Intrinsic flavour in proton 2. PDF including intrinsic heavy quark components 3. Hard parton-parton collisions 4. Intrinsic charm in proton and D-meson production in p-p at LHC 5.IC signal in the γ +c-jet production in p-p 6.ATLAS data on Z0(->l+l-)+b-jet production in p-p 7.IC signal in the γ*/Z0(->l+l-) +c-jet production in p-p 8. Summary OUTLINE 2

J.Pumplin, H.L. Lai and W.K.Tung, Phys.Rev.D75 (2007) 054029 BHPS model S.J. Brodsky,P. Hoyer, C. Peterson and N. Sakai, Phys.Lett. B93 (1980) 451; S.J. Brodsky, S.J. Peterson and N. Sakai, Phys.Rev. D23 (1981) 2745. MIT bag model: J.F. Donoughe, E.Golowich, Phys.Rev.D15 (1977) 3421. is J.Pumplin, H.L. Lai and W.K.Tung, Phys.Rev.D75 (2007) 054029

INTRINSIC HEAVY QUARK STATES Two types of parton contributions The extrinsic quarks and gluons are generated on a short time scale in association with a large transverse-momentum reaction. The intrinsic quarks and gluons exist over a time scale independent of any probe momentum, they are associated with the bound state hadron dynamics.

Gluon-exchange & vacuum-polarization graphs Diagrams which give rise to the intrinsic heavy quarks within the proton. Dashed and curly lines represent transverse and longitudinal-scalar (instantons) gluons, respectively. (S.J.Brodsky, C.Peterson, N.Sakai, Phys.Rev. D23 (1981) 2745. )

The x-distribution of the charm quarks xc(x,Q2) in proton; the solid black line is the IC contribution with its probability about 3.5 %, the dash green curve is the see charm quark contribution xcsea (x,Q2) at Q2=1.69 GeV2. There is enhancement at x>0.1.

The x-distribution of the charm quarks xc(x,Q2) in proton; the solid black line is the IC contribution with its probability about 3.5 %, the dash red curve is the see charm quark contribution xcsea (x,Q2) at Q2=1000GeV2. There is enhancement at x=0.2-0.4.

Comparison of the HERMES data with calculation within the BHPS at Q2 about 2.5 Gev2, μ is the QCD scale. A.Airapetian, et al., Phys.Lett.B666 (2008) 446; J.Peng, W.Cheng, hep-ph/1207.2193.

PHOTON & c(b)–JETS DI-LEPTON & c(b) -JETS PHOTON (DI-LEPTON) AND c(b)-JETS PRODUCTION IN P-P PHOTON & c(b)–JETS DI-LEPTON & c(b) -JETS Fig.a. Feynman diagram for the process Fig.b. Feynman graph for the process To observe the IC for Fig.a for Fig.b

Main subprocess for

A Monte Carlo for FeMtobarn processes at Hadron Colliders MCFM A Monte Carlo for FeMtobarn processes at Hadron Colliders We calculated the processes 12: 17: and their sum within the NLO QCD

SUMMARY 1. The production of heavy flavours at LHC can give us the information on the proton structure. 3. Some enhancement due to the intrinsic charm can be seen in the PDF (CTEQ66c) at x>0.1 and any Q2. 4.The measurements of the inclusive spectra of photons in the reaction give us a new information on the intrinsic charm contribution in the proton. 5. The signal of the IC contribution can be about 200% in the photon-c(jet) production at ~150 GeV/c and about 300 % at ~ 300 GeV/c. 6.The IC signal can be measured also in the production of vector bosons and heavy flavour jets. In the dN/dpT b of the process the IC signal can be about 300 % at high pTb SUMMARY measured at ATLAS can

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BACK UP

INTRINSIC STRANGENESS IN PROTON There is an enhancement at x>0.1 Strange hadron production in p-p collisons

Comparison of the HERMES data with calculation within the BHPS at Q2 about 2.5 Gev2, μ is the QCD scale. A.Airapetian, et al., Phys.Lett.B666 (2008) 446; J.Peng, W.Cheng, hep-ph/1207.2193.

STRANGENESS IN PROTON x Red line is without (IS), green line is with (IS); the probability of the IS is about 2.5 %. The points are the HERMES data arXiv:0803.2993 [hep-ex]; Q2=2.5 GeV2.

Tzvetalina Stavrevas’ calculation for

Subprocess for Subprocess for

WITHOUT SINGLE-TOP SUBTRACTION

Single production in p-p at TeV. G.L., V.A.Bednyakov, A.F.Pikelner, N.I.Zimin, Eur.Phys.Lett. 96 (2012)21002. To observe the IC we need

The experimental data on the di-muon mass distribution for events with at least one b-tagged jet with pt >25 GeV/c and |y|<2.1. The contribution estimated from the simulated MC samples of the signal and various background processes was shown. (ATLAS Colalboration, arXiv:1109.1403 [hep-ex])

The experimental data on the di-electron mass distribution for events with at least one b-tagged jet with pt >25 GeV/c and |y|<2.1. The contribution estimated from the simulated MC samples of the signal and various background processes was shown. (ATLAS Colalboration, arXiv:1109.1403 [hep-ex])

Gluon-exchange & vacuum-polarization graphs Diagrams which give rise to the intrinsic heavy quarks within the proton. Curly and dashed lines represent transverse and longitudinal-scalar (instantons) gluons, respectively. (S.J.Brodsky, C.Peterson, N.Sakai, Phys.Rev. D23 (1981) 2745. )

We included only hard subprocesses LO QCD diagram a)

OUTLINE 1. Intrinsic flavour in proton 2. PDF including intrinsic heavy quark components 3. Hard parton-parton collisions 4. Intrinsic charm in proton and D-meson production in p-p at LHC 5.IC signal in the γ +c-jet production in p-p 6.ATLAS data on Z0(->l+l-)+b-jet production in p-p 7.IC signal in the γ*/Z0(->l+l-) +c-jet production in p-p 8. Summary OUTLINE 35