  Maximizing the sustainable supercurrent density, Jc, is crucial to high
current applications of superconductivity and, to achieve this, preventing
dissipative motion of quantized vortices is key. Irradiation of superconductors
with high-energy heavy ions can be used to create nanoscale defects that act as
deep pinning potentials for vortices. This approach holds unique promise for
high current applications of iron-based superconductors because Jc
amplification persists to much higher radiation doses than in cuprate
superconductors without significantly altering the superconducting critical
temperature. However, for these compounds virtually nothing is known about the
atomic scale interplay of the crystal damage from the high-energy ions, the
superconducting order parameter, and the vortex pinning processes. Here, we
visualize the atomic-scale effects of irradiating FeSexTe1-x with 249 MeV Au
ions and find two distinct effects: compact nanometer-sized regions of crystal
disruption or 'columnar defects', plus a higher density of single atomic-site
'point' defects probably from secondary scattering. We show directly that the
superconducting order is virtually annihilated within the former while
suppressed by the latter. Simultaneous atomically-resolved images of the
columnar crystal defects, the superconductivity, and the vortex configurations,
then reveal how a mixed pinning landscape is created, with the strongest
pinning occurring at metallic-core columnar defects and secondary pinning at
clusters of pointlike defects, followed by collective pinning at higher fields.
