Precision measurement of the $B_c^{+}$ meson mass

A precision measurement of the $B_c^{+}$ meson mass is performed using proton-proton collision data collected with the LHCb experiment at centre-of-mass energies of $7,8$ and $13$ TeV, corresponding to a total integrated luminosity of $9.0{\mathrm{f}\mathrm{b}}^{-1}$. The $B_c^{+}$ mesons are reconstructed via the decays $B_{c}^{+} \rightarrow J\mskip -3mu/\mskip -2mu\psi\mskip 2mu \pi^+$,$B_{c}^{+} \rightarrow J\mskip -3mu/\mskip -2mu\psi\mskip 2mu \pi^+ \pi^- \pi^+$,$B_{c}^{+} \rightarrow J\mskip -3mu/\mskip -2mu\psi\mskip 2mu p \bar{p} \pi^+$,$B_{c}^{+} \rightarrow J\mskip -3mu/\mskip -2mu\psi\mskip 2mu D_{s}^{+}$,$B_{c}^{+} \rightarrow J\mskip -3mu/\mskip -2mu\psi\mskip 2mu D^{0} K^{+}$and$B_{c}^{+} \rightarrow B_{s}^{0} \pi^{+}$\mathrm{.}Combiningtheresultsoftheindividualdecaychannels,the$B_{c}^{+}$massismeasuredtobe$6274.47 \pm 0.27 ,({\rm stat}) \pm 0.17 ,({\rm syst}) $\mathrm{M}\mathrm{e}\mathrm{V}$/c^{2}$. This is the most precise measurement of the $B_c^{+}$ mass to date. The difference between the $B_c^{+}$ and $B_s^0$ meson masses is measured to be $907.75 \pm 0.37 ,({\rm stat}) \pm 0.27 ,({\rm syst}) $\mathrm{M}\mathrm{e}\mathrm{V}$/c^{2}$.