Measuring Track-Related Pointing Errors on the Nanshan Radio Telescope with an Optical Pointing Telescope

Figure 5

Measured and model predicted values of the alidade twist. The red solid line shows the ex values obtained by extracting the P₁₇ and P₁₈ terms from the overall pointing model, where the P₁₇ and P₁₈ coefficient values were obtained from the “Radio model” column of Table 4. The blue solid line represents the measured alidade twist values obtained from the pointing model using P₁₇ and P₁₈ parameters in the “measured twist” column of Table 4. The black dashed line represents the predicted ex value by the track-alidade model, based on the height profile measured by Wen et al. [13].