Journal of High Energy Physics

, 2012:115 | Cite as

Exclusive final states in diffractive excitation

  • Christoffer Flensburg
  • Gösta Gustafson
  • Leif Lönnblad


In this paper we describe a formalism for generating exclusive final states in diffractive excitation, based on the optical analogy where diffraction is fully determined by the absorption into inelastic channels. The formalism is based on the Good-Walker formalism for diffractive excitation, and it is assumed that the virtual parton cascades represent the diffractive eigenstates defined by a definite absorption amplitude. We emphasize that, although diffractive excitation is basically a quantum-mechanical phenomenon with strong interference effects, it is possible to calculate the different interfering components to the amplitude in an event generator, add them and thus calculate the reaction cross section for exclusive diffractive final states. The formalism is implemented in the DIPSY event generator, introducing no tunable parameters beyond what has been determined previously in studies of non-diffractive events. Some early results for DIS and proton-proton collisions are presented, and compared to experimental data.


Phenomenological Models Monte Carlo Simulations 


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Copyright information

© SISSA, Trieste, Italy 2012

Authors and Affiliations

  • Christoffer Flensburg
    • 1
  • Gösta Gustafson
    • 1
  • Leif Lönnblad
    • 1
  1. 1.Department of Astronomy and Theoretical PhysicsLund UniversityLundSweden

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