Secondary electron emission from water vapor under 6.0 MeV/u C6+ion impact

Further improving our previous apparatus, we have successfully measured absolute double differential cross section (DDCS) for secondary electron emission (1 eV-10 keV and 20-160°) produced in the collision of 6.0 MeV/u C6+ ion with water vapor. The angular distributions of DDCSs disagree with the CDW-EIS theoretical calculation at the backward angles (>100°), while single differential cross section (SDCS) agrees well with the CDW-EIS, particularly in the low-energy region (<200 eV).