Constraints on new physics from rare (semi-)leptonic B decays

TL;DR

Recent measurements of rare leptonic and semi-leptonic B decays at the LHC align with the Standard Model, providing stringent constraints on new physics models, especially those involving flavor-changing Z couplings in partial compositeness frameworks.

Contribution

The paper discusses how current experimental results restrict new physics models, with a focus on partial compositeness and flavor-changing Z interactions in rare B decays.

Findings

No significant deviations from the Standard Model observed.

Strong constraints placed on models with flavor-changing Z couplings.

Future experiments will further test these models.

Abstract

The measurements of rare leptonic and semi-leptonic B decays performed at the LHC, not showing any significant deviations from the Standard Model expectations, put strong constraints on new physics. A brief account of the impact of recent measurements is given. As a concrete example, models with partial compositeness are discussed, where tree-level flavour-changing Z couplings lead to potentially visibile effects in rare B (and K) decays that will be scrutinized experimentally in the near future.