1. 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

2. 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

3. 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)

4. 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.

5. 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) )

6. 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.

7. 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=

8. 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/

9. 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

17. Main subprocess
for

18. 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

20. 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

21. THANK YOU VERY MUCH FOR YOUR ATTENTION !21

22. BACK UP

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

24. 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/

25. 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: [hep-ex]; Q2=2.5 GeV2.

26. Tzvetalina Stavrevas’ calculation for

27. Subprocess for
Subprocess for

28. WITHOUT SINGLE-TOP SUBTRACTION

30. 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

31. 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: [hep-ex])

32. 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: [hep-ex])

33. 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) )

34. We included only hard subprocesses
LO QCD diagram a)

35. 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