Extension of NIMROD's synthetic diagnostics: CES and particle transport in perturbed magnetic topologies

We present a synthetic Charge Exchange Spectroscopy (CES) diagnostic to assess the detectability of magnetic islands in KSTAR plasmas, showing that CES can reliably detect island-induced flattening of T_C⁶⁺ profiles when the island width exceeds a critical threshold set by the C⁶⁺ Larmor radius. Using the particle tracer capabilities of the NIMROD and M3D-C1 + MAFOT plasma response codes, we trace large ensembles of test particles with Maxwellian velocity distributions, both with and without collisions, to quantify this threshold. These synthetic diagnostics benchmark KSTAR CES observations and clarify the resolution limits imposed by finite ion orbits of C⁶⁺. This work also continues the expansion of NIMROD capabilities, following prior development of a synthetic ECE-I diagnostic, and will support future studies of tungsten transport in the stochastic edge of metal-wall machines for improved impurity control in reactor relevant conditions. In addition, we aim to quantify diffusion rates in chaotic magnetic fields and compare them to existing theoretical predictions in order to set up a basis for future analytical studies.