STUDY OF THE HIGH ORDER TERMS OF THE BORN SERIES: 
THE  B1B-CDW APPROXIMATION FOR ELECTRON CAPTURE

S. E. Corchs, O. A. Foj\'on   and R.D. Rivarola

Instituto de F\'{\i}sica Rosario (CONICET-UNR), Av. Pellegrini 250,
2000 - Rosario, Argentina

In this work we study the contribution to the electron capture process
of the higher orders of the Born series
with correct boundary conditions. A new approximation is developed within
the distorted wave model. Single differential and total cross sections are
obtained for hydrogenic targets and heavy projectiles at high and
intermediate
energies.