The ratio of Rise Time to Fall Time. A value of 1.0 means the field ramps up and down at equal speed (symmetric). Values below 1.0 indicate a faster rise than fall. Values above 1.0 indicate the opposite. Asymmetric pulses deliver a different induced stimulus on each edge, since the induced field tracks the rate of change. Values within 15% of 1.0 are considered symmetric.
One pulse over time. The field climbs from rest to its peak, holds, then falls back. How fast that rising edge climbs is the slew rate, and a steeper edge drives a stronger stimulus. The rise time and fall time are measured between the 10% and 90% levels; the pulse width is measured at half the peak.
