First exclusive reconstruction of the B*+, B*0, and B*0s mesons and precise measurement of their masses

Using proton-proton collision data collected by the CMS experiment at √𝑠=13  TeV in 2016–2018, corresponding to an integrated luminosity of 140  fb−1, the first full reconstruction of the three vector 𝐵 meson states, 𝐵*+, 𝐵*0, and 𝐵*0𝑠, is performed. The mass differences between the excited mesons and their corresponding ground states are measured to be 𝑚⁡(𝐵*+)−𝑚⁡(𝐵+)=45.277±0.039±0.027  MeV, 𝑚⁡(𝐵*0)−𝑚⁡(𝐵0)=45.471±0.056±0.028  MeV, and 𝑚⁡(𝐵*0𝑠)−𝑚⁡(𝐵0𝑠)=49.407±0.132±0.041  MeV, where the first uncertainties are statistical and the second are systematic. These results improve on the precision of previous measurements by an order of magnitude.