Fig. 2

Mean SNR for each of the beams for the entire observational period (top left), the radial velocity acceptance rates for each range for the six beams using a 3-dB acceptance criterion (top right), the scattering angle \(\theta_{\text{s}}\) calculated from each of the off-zenith beams and the mean of these (in olive, centre) (bottom left), and the mean effective beam angle \(\theta_{\text{E}}\) for each of the beams (bottom right). The 3-dB acceptance criterion has also been applied to calculate \(\theta_{\text{s}}\) and \(\theta_{\text{E}}\). The beams are colour coded as: vertical, red; north-west, blue; north, green; north-east, orange; south-west, brown; and west, purple