Multiparton interactions with an x-dependent proton size

  • Richard Corke
  • Torbjörn Sjöstrand


Theoretical arguments, supported by other indirect evidence, suggest that the wave function of high-x partons should be narrower than that of low-x ones. In this article, we present a modification to the variable impact parameter framework of Pythia 8 to model this effect. In particular, a Gaussian hadronic matter profile is introduced, with a width dependent on the x value of the constituent being probed. Results are compared against the default single-and double-Gaussian profiles, as well as an intermediate overlap function.


QCD Phenomenology Phenomenological Models 


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Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  1. 1.Theoretical High Energy Physics, Department of Astronomy and Theoretical PhysicsLund UniversityLundSweden

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