The (m(+), e(-), e(+)) system as a positronic atom

The stochastic variational method is used to investigate the stability of t he (m(+), e(-), e(+)) system as a function of the m(+)/m(e), mass ratio. Th e system was found to be stable for 0.697 78 less than or equal to m(+)/m(e ) less than or equal to1.6343. These mass limits correspond to stability fo r energy values of the (m(+), e(-)) subsystem satisfying 0.205 498 less tha n or equal to E(m(+), e(-)) less than or equal to 0.310196 (energies in Har tree). These energy limits correspond roughly to the ionization potentials of neutral atoms that are known to bind a positron. The (m(+), e(-), e(+)) system can be regarded as an analogue of a typical positronic atom since th e structure of the (m(+), e(-), e(+)) system as a function of E(m(+), e(-)) is seen to he reminiscent of the structure of positronic atoms as a functi on of the parent atom ionization potential.