Electron energy dependence of extreme ultraviolet spectra from highly charged tungsten ions in an electron beam ion trap

We present the electron beam energy dependence of the emission intensity ratio of W45+ to W44+ for the 4s-4p transitions measured by using an electron beam ion trap. The ratio is important for the charge state abundance diagnostics of fusion plasmas; and the benchmark experimental data are thus required for the accurate diagnostics. Experimental results are compared to the theoretical ones evaluated with the flexible atomic code.