ENERGIES OF SYMMETRICAL MESIC MOLECULES

The nonrelativistic energy E(m, M) of symmetric four-particle mesic mo lecules consisting of two pairs of identical particles is considered a s a function of the particle masses m and M, The expansion of the func tion E(m, M) in a series of the Born-Oppenheimer type is found with al lowance for its symmetry under the permutation of the pairs of particl es and for its behavior at small and large values of the ratio s = m/M . This expansion and available results of precision calculations of th e hydrogen molecule and of mesic molecular systems are used to constru ct a reliable six-term formula for calculating the energies of symmetr ic four-particle mesic molecules with arbitrary particle masses rta an d M. With the aid of this formula, prediction are obtained for the dis sociation energies of the mesic molecular systems mu(+)mu(+)e(-)e(-), pi(+)pi(+)e(-)e(-), pi(+)pi(+)mu(-)mu(-), K(+)K(+)e(-)e(-), K(+)K(+)mu (-)mu(-), and d(+)d(+)p(-)p(-), for which variational calculations hav e not yet been performed.