Correlations in double parton distributions at small x

  • Christoffer Flensburg
  • Gösta Gustafson
  • Leif Lönnblad
  • Andras Ster
Open Access


We present a dynamical study of the double parton distribution in impact parameter space, which enters into the double scattering cross section in hadronic collisions. This distribution is analogous to the generalized parton densities in momentum space. We use the Lund Dipole Cascade model, presented in earlier articles, which is based on BFKL evolution including essential higher order corrections and saturation effects. As result we find large correlation effects, which break the factorization of the double scattering process. At small transverse separation we see the development of “hot spots”, which become stronger with increasing Q 2. At smaller x-values the distribution widens, consistent with the shrinking of the diffractive peak in elastic scattering. The dependence on Q 2 is, however, significantly stronger than the dependence on x, which has implications for extrapolations to LHC, e.g. for results for underlying events associated with the production of new heavy particles.


QCD Phenomenology Phenomenological Models 


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© The Author(s) 2011

Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  • Christoffer Flensburg
    • 1
  • Gösta Gustafson
    • 1
  • Leif Lönnblad
    • 1
    • 2
  • Andras Ster
    • 1
    • 3
  1. 1.Dept. of Astronomy and Theoretical PhysicsLund UniversityLundSweden
  2. 2.CERN Theory DepartmentGenevaSwitzerland
  3. 3.MTA KFKI-RMKI Department of Theoretical PhysicsBudapestHungary

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