In light of the recent measurement of the B^+ \to K^+ \nu\nu branching ratio from the Belle II experiment, which results to be about 3 or more times larger than the Standard Model prediction, I will show the main new physics scenarios that have been considered and studied in literature so far in order to explain the observed excess of events.
Papers:
https://arxiv.org/pdf/2308.13426.pdf
https://arxiv.org/pdf/2309.17191.pdf