  This paper investigates energetic electron transport in magnetized toroidal
plasmas with magnetic fields characterized by island chains and regions of
stochastic field lines produced by coil perturbations. We report on experiments
performed in the DIII-D tokamak, which utilize electron cyclotron heating and
current drive pulses to tag electron populations within different locations
across the discharge. The cross-field transport of these populations is then
inferred from electron cyclotron emission measurements and gamma emission
signals from scintillator detectors. Two types of energetic particles are
distinguished and discussed: nonrelativistic suprathermal electrons and
relativistic runaway electrons. The magnetic field topology in each discharge
is reconstructed with field line tracing codes, which are also used to
determine the location and scale of magnetic islands and stochastic regions.
Comparison of simulations and experiments suggests that suprathermal transport
is suppressed when the tagging is performed at a smaller radial location than
the location of the q=1 island chain, and enhanced otherwise. We further
demonstrate that increasing the width of the stochastic region within the edge
plasma yields enhancement of the suprathermal electron transport.
