NICER observation list: Target ID 258501

The launch of NICER brings unprecedented capabilities for observing magnetic cataclysmic variables ( polars'). Quasi-periodic oscillations (QPOs) of 1-3 s have been observed with fast optical photometry. Existing hydrodynamic models of the accretion unify the source spectrum with predictions for a 2-channel (X-ray and optical) QPO. The X-ray QPO has never been detected, but observing capabilities have been limited. We propose NICER observations of the five polars that have exhibited optical QPOs, complemented by optical coverage from SAAO, both for cross correlation of variability and to understand source state changes. The campaign will compare both the spectral and temporal aspects with models. Detecting even one X-ray QPO would be an enormous advance.