Figure 3.

Photograph of Gamma Knife headframe (a) showing that the length of the longest post is $~15\hspace{0.17em}\text{cm}$, which is much lower than the expected length required for heating via the antenna effect, which would be $~60\hspace{0.17em}\text{cm}$. Plot (b) of the time dependence of the temperature taken at the top of the headframe post, showing that there is no heating with the melon absent (triangles), but significant heating at the screw tips when the melon is mounted in the headframe (circles).