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One of the fundamental properties of an intermediate polar is the dynamicalnature of the accretion flow as it encounters the white dwarf's magnetosphere.Many works have presumed a dichotomy between disk-fed accretion, in which theWD accretes from a Keplerian disk, and stream-fed accretion, in which thematter stream from the donor star directly impacts the WD's magnetospherewithout forming a disk. However, there is also a third, poorly understoodregime in which the accretion flow consists of a torus of diamagnetic blobsthat encircles the WD. This mode of accretion is expected to exist atmass-transfer rates below those observed during disk-fed accretion, but abovethose observed during pure stream-fed accretion. We invoke the diamagnetic-blobregime to explain the exceptional TESS light curve of the intermediate polar TXCol, which transitioned into and out of states of enhanced accretion duringCycles 1 and 3. Power-spectral analysis reveals that the accretion wasprincipally stream-fed. However, when the mass-transfer rate spiked,large-amplitude quasi-periodic oscillations (QPOs) abruptly appeared anddominated the light curve for weeks. The QPOs have two striking properties:they appear in a stream-fed geometry at elevated accretion rates, and theyoccur preferentially within a well-defined range of frequencies (~10-25 cyclesper day). We propose that during episodes of enhanced accretion, a torus ofdiamagnetic blobs forms near the binary's circularization radius and that theQPOs are beats between the white dwarf's spin frequency and unstable bloborbits within the WD's magnetosphere. We discuss how such a torus could be acritical step in producing an accretion disk in a formerly diskless system.

Quasi-periodic oscillations in the TESS light curve of TX Col, a diskless intermediate polar on the precipice of forming an accretion disk