Angular analyses of exclusive $\overline{B}\to X_J{\ell }_1{\ell }_2$ decays for spin $J\le 4$

Abstract

As an update to our previous calculation for spin $J\le 2$, we present the angular moments for exclusive $\overline{B}\to X_J{\ell }_1{\ell }_2$, where ${\ell }_1$ is a charged massless lepton and ${\ell }_2$ is a charged or neutral massless lepton, and $X_J$ is a mesonic system with spin $J\le 4$. The expected applications include higher resonances in the $[K\pi ]$ system in ${\overline{B}}^0\to K^{-}{\pi }^{+}{\mu }^{-}{\mu }^{+}$ at LHCb in Run~II, and in the $[\pi \pi ]$ system for $\overline{B}\to \pi \pi {\ell }^{-}{\bar{\nu }}_{\ell }$ at Belle~II. For the $J\le 2$ case, we also provide a set of consistency relations among the measured moments observables and validate them against the latest measurements from LHCb.