  We suggest a new adiabatic approach for description of three charged
particles in the continuum. This approach is based on the Coulomb-Fourier
transformation (CFT) of three body Hamiltonian, which allows to develop a
scheme, alternative to Born-Oppenheimer one.
  The approach appears as an expansion of the kernels of corresponding integral
transformations in terms of small mass-ratio parameter. To be specific, the
results are presented for the system $ppe$ in the continuum. The wave function
of a such system is compared with that one which is used for estimation of the
rate for triple reaction $ p+p+e\to d+\nu, $ which take place as a step of
$pp$-cycle in the center of the Sun. The problem of microscopic screening for
this particular reaction is discussed.
