New measurement of the π- -meson mass
Marushenko V.N., Mezentsev A.F., Petrunin A.A., Skornyakov S.G., Smirnov A.I.
We measured the energies of the π-mesic-atom 4/-3d transitions in Ti and Ca, equal respectively to 87 649.2± 1.9 and 72 347.0±1.1 eV. The normal value was taken to be the KalW energy from the β decay of 182Ta: 59 318.77±0.21 eV. Using the conversion factors given in m, we found for the rest mass of the π~ meson the value M„-c2= 139 565.7± 1.7 keV.