16727

White dwarfs (WD) in intermediate polars (IPs) rotate rapidly and have sufficiently high magnetic-field strengths to channel gas from an accretion disk onto their magnetic poles. The WD in FO Aquarii comma the so-called ''King of the IPs comma .. began spinning down in 2015 after spinning up for the preceding quarter-century. Almost immediately comma it began to drop into a series of low-accretion states in the optical and X-rays comma behavior that was never observed when the WD was spinning up. The power generated by the spin-down is nearly 0.5 Solar luminosities comma which raises a very basic questiondoublePoint where is this energy depositedquestionMark We hypothesize that during FO Aqr.s low states comma the WD powers an outflow that removes angular momentum from the WD comma causing the observed spin-down. This scenario is similar to X-ray binaries in which a magnetized neutron star comma after being spun-up by accretion comma develops a centrifugal barrier that drives outflows or even a jet. FO Aqr.s spin-down power is sufficiently high to drive a substantial outflow comma and although optical spectra of FO Aqr during its recent low state hint at the existence of this feature comma ultraviolet spectra are vastly more sensitive to outflowing gas because of the presence of C IV and Si IV resonance lines. We propose HST-COS observation of FO Aqr to test for outflow-jet signatures such as P-Cygni line profiles that were not present in UV spectra taken in 1995 when the WD was spinning up.