First evidence for mixing-induced $CP$ violation in B${}_{\mathrm{s}}^0$ $\to$ J/$\psi \varphi$(1020) decays in pp collisions at $\sqrt{s}=$ 13 TeV

CMS Collaboration

A novel machine-learning-based flavor-tagging algorithm combining same-side and opposite-side tagging is used to obtain the equivalent of 27000 tagged B${}_{\mathrm{s}}^0$ $\to$ J/…