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arXiv · 1506.09085

Colour Reconnection at Future $\mathrm{e}^\mathbf{+}\mathrm{e}^\mathbf{-}$ Colliders

Abstract

The effects of colour reconnection (CR) at $\mathrm{e}^+\mathrm{e}^-$ colliders are revisited, with focus on recently developed CR models. The new models are compared with the LEP2 measurements for $\mathrm{e}^+\mathrm{e}^- \to \mathrm{W}^+\mathrm{W}^- \to\mathrm{q}_1 \overline{\mathrm{q}}_2 \mathrm{q}_3 \overline{\mathrm{q}}_4$ and found to lie within their limits. Prospects for constraints from new high-luminosity $\mathrm{e}^+\mathrm{e}^-$ colliders are discussed. The novel arena of CR in Higgs decays is introduced, and illustrated by shifts in angular correlations that would be used to set limits on a potential $CP$-odd admixture of the 125 GeV Higgs state.

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Jesper R. Christiansen, Torbjörn Sjöstrand. 2015-06-30. Colour Reconnection at Future $\mathrm{e}^\mathbf{+}\mathrm{e}^\mathbf{-}$ Colliders. https://arxiv.org/abs/1506.09085

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