Abstract
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.
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Corke, R., Sjöstrand, T. Multiparton interactions with an x-dependent proton size. J. High Energ. Phys. 2011, 9 (2011). https://doi.org/10.1007/JHEP05(2011)009
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DOI: https://doi.org/10.1007/JHEP05(2011)009