TOPS coregistration accuracy

Hi,

Can anybody point me to a paper or some other resource that investigates the coregistration accuracy of S1 images using the SNAP TOPS function?

Or is there a way to measure the coregistration accuracy is SNAP? In the ‘back geocoding’ graph there is an option for ‘outputRangeAzimuthOffset’ but I don’t see an output. Also, this option is not available in GUI.