   Starbursts Left on Surface by High Voltage Breakdown  Daniel
Lundberg (graduate student) Program in Plasma Physics This
image, taken with an electron microscope, is of a niobium plate.
To investigate the effects of impure particles on
superconducting cavities for accelerators, small vanadium
particles were deposited on the plate, which was then charged
with several kilovolts relative to a nearby electrode. The
intense electric fields that formed on the sharp edges of the
vanadium particles caused them initiate high voltage breakdown.
Plasma was created, and as it expanded and dissipated, it left
behind complex starburst patterns on the surface.