DPF - PHENO 2024

An axion-like particle explanation of B→πK puzzle and B→Kνν¯ excess

16 May 2024, 14:15

15m

David Lawrence Hall 104 (University of Pittsburgh)

Quark and Lepton Flavor Physics Quark and Lepton Flavor Physics

Speaker

Shibasis Roy (Chennai Mathematical Institute)

Description

In light of the recent branching fraction measurement of $B^{+}\to K^{+}\nu \overline{\nu }$-decay and its deviation from the SM expectation, we analyze the prospect of an axion-like particle (ALP) as the cause of such a departure. We assume a long-lived ALP with a mass of the order of a pion that predominantly decays to two photons. We focus on the scenario where the ALP decay length is several meters and therefore a non-negligible probability to decay outside detector volume of Belle-II mimicking the $B^{+}\to K^{+}\nu \overline{\nu }$-signal. Remarkably, such an arrangement provides a simple explanation to the long-standing $B\to \pi K$-puzzle by noting that the measured $B^0\to {\pi }^0{K}^0$ and $B^{+}\to {\pi }^0{K}^{+}$ decays have a $B^0\to a{K}^0$ and $B^{+}\to a{K}^{+}$ component respectively. We also argue based on our results that the axion-photon effective coupling belongs to a region in the parameter space that is still allowed after considering all the constraints known from various experiments.

Presentation materials

APS DPF Roy.pdf