The ratio of population densities of C
3+ excited levels, C
3+(3p
2P
3⁄2), C
3+(n = 6), and C
3+(n = 7), indicates that C
3+(n = 7) is predominantly excited by electron collision with the ground state of C
3+ in attached plasmas. Hence, Doppler broadening of the C IV (n = 6-7) spectral line provides C
3+ temperature. Regression analysis of the spectrum results in two C
3+ temperature components. The higher C
3+ temperature ranges from 50 eV to 150 eV, the lower around 20 eV. From the results of the analyses with plasma and impurity transport codes and a collisional-radiative model, the higher and the lower C
3+ temperature correspond to the C
3+ temperature of the common flux (divertor) plasma and of the private plasma, respectively. In the inner divertor, C
3+ temperature is close to D
+ temperature, and the C IV spectral line is predominantly emitted around the inner divertor leg. Therefore, it is concluded that D
+ temperature around the inner divertor leg can be measured from the C IV spectral line. On the contrary, it is found difficult to measure the D
+ temperature in the outer divertor.
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