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Neutral Pion-like Resonances at Photon Colliders

Kingman Cheung·Hsin-Wu Tseng
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Abstract

Two photons can annihilate into a neutral pion-like resonance via the anomaly coupling, just like $π^0γγ$ in QCD. In some strongly interacting electroweak symmetry breaking models, e.g., technicolor type models, there often exist neutral pion-like resonances. TeV photon colliders have a strong capability to discover such particles, because the standard model background in photon scattering goes through box diagrams and is therefore highly suppressed. In this study, we perform a signal-background comparison. We show that $e^+ e^-$ linear colliders running in $γγ$ mode can discover such neutral-pion-like resonances with a decent sensitivity.

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Kingman Cheung, Hsin-Wu Tseng. 2004-11-30. Neutral Pion-like Resonances at Photon Colliders. https://doi.org/10.1103/physrevd.71.037501

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