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arXiv · 1202.5073

Constraints on large scalar multiplets from perturbative unitarity

Katy Hally·Heather E. Logan·Terry Pilkington
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Abstract

We determine the constraints on the isospin and hypercharge of a scalar electroweak multiplet from partial-wave unitarity of tree-level scattering diagrams. The constraint from SU(2)_L interactions yields T <= 7/2 (i.e., n <= 8) for a complex scalar multiplet and T <= 4 (i.e., n <= 9) for a real scalar multiplet, where n = 2T+1 is the number of isospin states in the multiplet.

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Katy Hally, Heather E. Logan, Terry Pilkington. 2012-03-05. Constraints on large scalar multiplets from perturbative unitarity. https://doi.org/10.1103/physrevd.85.095017

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