Comparison between the Urumqi 4.8 GHz survey and the Parkes 5 GHz survey. (a) Pixel-by-pixel comparison of the observed brightness temperatures of the two survey datasets within 10° < ℓ < 30°. The dashed red line indicates the equality between the two datasets. (b) Histogram of the brightness temperature differences between the two surveys. The vertical dashed line denotes the median value of 0.028 K. (c) Brightness temperature difference as a function of the Galactic latitude for ℓ = 11°65. The dashed red curve represents the polynomial fit to the observed distribution.