  Stereo-dynamics of dissociative electron attachments to CO_2 is investigated
by the O^- anion velocity imaging experiments combined with the R-matrix
calculations. ^2{\Pi}_g as a Feshbach resonant state of CO_2^- is confirmed to
play roles in the dissociations around 8.0 eV. We find that the dynamic
evolutions of the Renner-Teller effect lead to the dramatically different
anisotropic O^- momentum distributions.
