Mean energy losses of foil-transmitted H-2+ ions are measured for the
incidence of 9.6-MeV/amu H-2+, ions on carbon foils of 1.5-8.5 mug/cm2
thickness. The measured ions are those that have traversed the carbon
foil without loss of their original electrons. The stopping power of
carbon for 9.6-MeV/amu H-2+ ions, derived from the energy losses, is 5
5.8+/-4.6 eV/(mug/cm2). The obtained stopping power is compared with t
hat calculated with the first Born approximation. The calculated resul
t is slightly larger than the experimental one.