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^*0_𝑠, 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^*0_𝑠) −𝑚 (𝐵⁰_𝑠) =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.
Collaboration et al. (Thu,) studied this question.