Search for new physics in $B \to K \pi \pi \gamma$ with Belle II data

Sahil Saha

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arXiv · 2604.26315

Search for new physics in $B \to K \pi \pi \gamma$ with Belle II data

Sahil Saha

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Abstract

The measurement of the time-dependent CP-asymmetry of $B^0 \to K_S^0 \pi^+ \pi^- \gamma$ decays is sensitive to contributions from physics beyond the Standard Model. To translate this measurement into a constraint on new physics, it is necessary to distinguish between decay modes that contribute to the final state via a kaonic resonance that is a CP eigenstate, and those that proceed through non-CP eigenstates. This requires an amplitude analysis of the $B \to K_{res} \gamma \to K \pi^+ \pi^- \gamma$ decay, that is discussed in this article.

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Sahil Saha. 2026-04-29. Search for new physics in $B \to K \pi \pi \gamma$ with Belle II data. https://arxiv.org/abs/2604.26315

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