title:Mechanism of doubly excited He by double electron transfer from neutral atoms authors:T. Watanabe, X. M. Tong, S. Ohtani, K. Iemura, Y. Kanai and H. Suzuki afiliations:International Christian University, University of Kansas, University of Electro-Communications, and Institute of Physical and Chemical Research summary: Formation mechanism of a doubly excited helium by collision of He++ with Sr or Ba atoms is considered. Two electron transfer process by the level crossing which is largely affected by the magnitude of polarizability of Sr or Ba, and that of excited He. Polarizability of excited He is obtained by CI calculation based on Hartree-Slater SCF wavefunctions.