The first graph shows the declination tilt based on median filtered data for RCW 57, taken March 20-21, 2000. The best fit to a sinusoid gives an amplitude of 2.4' peak-to-peak for the tilt of the base.



The second graph shows the pointing offsets for all 46 RCW 57 scans from the 20th and 21st. The x axis is days from March 20.2, and the y axis is the pointing offset in degrees. The blue "x" points are RA offsets, the red circles are dec offsets. It should be noted that the high RA points are detections of the nearby source NGC 3603 (which is typically somewhat fainter than RCW 57 but due to bad-signal to noise or transmission variations will sometimes be selected by the fitting program as the brighter source). NGC 3603 is about 0.4 real degrees towards the East from RCW 57.



The third graph has all outlying data points removed, and a 0.04 degree amplitude tilt has been drawn in red. This is not a fit curve, and close inspection reveals a slight phase mismatch between the drawn curve and the phase suggested by the raw data.