'DC' and pulsed; some with gaps (the area of uniform field across the pole tips) large enough to get into.
(Once placed head near pole-tips of a pulsed 15 KGauss field - more likely ~5000 gauss at my spot. On that one, eyes closed - 'saw' bluish sparks, at the rep-rate of 6 pps.)
Nothing wraithlike.. in, above or near the jelloware or its I/O.
'Definition of a tragedy - a theory killed with a fact' [experiment?