Dan Gerous, re 'expanding rod'.
Yes the photograph shows a pattern normally associated with an expanding rod warhead.
Red Top - IR homing on the flare; typically, the dark doughnut explosive ring (to the fore of the bright clover leaf) gives some spin to the ring, thus the effect is like a band saw.
Its a good picture, but begs the question where were did all of the other segments of the ring go … , photo-chase break off now !