Phenomenology of inclusive $\bar{B}\to X_s \ell^+ \ell^-$ for the Belle II era

Understand

With the first data being recorded at Belle II, we are at the brink of a new era in quark flavour physics.

• The many exciting new opportunities for Belle~II include a full angular analysis of inclusive ${\bar B \to X_{s} \, \ell^+\ell^-}$ which has the potential to reveal new physics, in particular by its interplay with the exclusive $b \to s \ell^+\ell^-$ counterparts studied extensively at LHCb.
• In this paper, we present fully updated Standard Model predictions for all angular observables necessary for this endeavour.
• These predictions are tailored to Belle II and include an elaborate study of the treatment of collinear photons which become crucial when aiming for the highest precision.