Footprints of leptoquarks: from $ R_{K^{(*)}} $ to $ K \to \pi \nu \bar\nu $

Understand

Rare $K \to \pi \nu \bar \nu$ decays, being dominated by short distance contributions within the Standard Model (SM), open a window for New Physics (NP) searches at low energies.

• The $ K \to \pi \nu \bar\nu $ branching ratios are expected to be measured with $ \sim 10\% $ accuracies by NA62/CERN and KOTO/JPARC.
• The theoretical uncertainties of branching ratios within the SM are well under control.
• In the $ B $ sector, it is tentative to explain the $ B $-meson anomalies $ R_{D^{(\ast)}} $ and/or $ R_{K^{(\ast)}} $ by effects of physics beyond the SM.