1. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 1 Total, elastic and inelastic cross sections of high energy pp, pA and  * A reactions with dipole formalism Wigner Research Centre for Physics, Budapest, Hungary András Ster Work in collaboration with Gösta Gustafson and Leif Lönnblad in Dept. of Astronomy and Theoretical Physics, Lund University, Sweden

2. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 2 Content Motivations The Lund Dipole Cascade Model Application in MC event generator DIPSY Preliminary DIPSY-MC cross section results Summary

3. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 3 Motivations An example: the PYTHIA MC-model is the most successful description of inelactic reaction in DIS and pp collisions. But: there are simplified assumptions about correlations and diffraction. Our goal: to undestand underlying dynamics in more detail. - evolution of parton densities - correlations and fluctuations - diffraction - nuclear collisions

4. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 4 Motivations: correlations Our solution: detailed dynamical model for parton evolution (Lund Dipole Cascade Model) Earlier Sjöstrand and van Zilj assumed that the dependence of double-parton density on kinematic variables (x, Q 2 ) and on the separation in impact parameter space (b) factorizes. Implemented in PYTHYA and HERWIG event generators Problem: how to extrapolate to higher energies (LHC)

5. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 5 The Lund Dipole Cascade Model is based on BFKL evolution equations and Müller’s dipole cascade model: Motivations: a new improved model

6. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 6 The Lund Dipole Cascade Model With the constraint: It improves BFKL evolutions :

7. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 7 The Lund Dipole Cascade Model Dipole cascades: LL BFKL evolution in transverse coordinate space Gluon emission probality:

8. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 8 The Lund Dipole Cascade Model Dipole-dipole scattering:

9. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 9 The Lund Dipole Cascade Model Saturation:

10. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 10 The Lund Dipole Cascade Model Inclusive observables: With the ikonal form of the transition probability:

11. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 11 The Lund Dipole Cascade Model In the (Glauber like) black disk limit : Hence:

12. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 12 Application in DIPSY-MC It includes: - important not-leading effects in BFKL (E cons., runnnig  s ) - saturation in pomeron loops in the evolution - confinement - correlations and fluctuation - collision between e,p,A

13. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 13 Application in DIPSY-MC Dipole interactions:

14. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 14 Application in DIPSY-MC Sample Au-Au event:(nucleons are dipole triangles here)

15. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 15 Application in DIPSY-MC Sample Au-Au event:

16. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 16 Application in DIPSY-MC Sample Au-Au event:

17. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 17 Cross section results Simulations are based on tunes of a few model parameters to pp total cross sections. An example:  QCD.

18. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 18 Cross section results Main model parameters in DIPSY:

19. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 19 Cross section results parameters tuned to:  QCD = 0.23 GeV R p = 0.57 fm

20. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 20 Cross section results GLISSANDRO **: provides nucleon center density * : H. DeVries et al., Atom. Data Nucl. Tabl. 36 (1987) **: W.Broniowski et al., GLISSANDRO, nucl-th/0710.531v3 Ion MC’s are based on theWood-Saxon nucleus charge density*:

21. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 21 Cross section results Total inelastic pPb data: CMS: preliminary LHCb: first measurement

22. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 22 Cross section results

23. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 23 Cross section results

24. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 24 Cross section results

25. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 25 Cross section results

26. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 26 Cross section results

27. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 27 Cross section results

28. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 28 Cross section results

29. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 29 DIPSY vs Glauber cross section results Same initial conditions: - WS distribution - hard-core = 0.45fm - input: pp  inelND

30. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 30 DIPSY vs Glauber cross section results

31. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 31 Cross section results Further ongoing simulations are for: - AA collisions (take lots of execution time) - dn/dy distributions

32. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 32 Outlook Things to do: - speed-up large ion calculations - final state effects - diffractive final states - NLL effects -...

33. Zimanyi-School, Budapest, 03/12/2014 A. Ster, Wigner-RCP, Hungary 33 Summary Reconstruction of pp total cross sections from RHIC energies to LHC energies and pPb inelastic ones at 5 TeV was successful. Lund Dipole Cascade Model offers unique possibility to study gluon evolution inside hadrons at small x Predictions for total cross sections in various pA,  *A high energy collisions were made.