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We present the Transiting Exoplanet Surveying Satellite (TESS) light curve ofthe intermediate polar YY Draconis (YY Dra, also known as DO Dra). The powerspectrum indicates that while there is stream-fed accretion for most of theobservational period, there is a day-long, flat-bottomed low state at thebeginning of 2020 during which the only periodic signal is ellipsoidalvariation and there is no appreciable flickering. We interpret this low stateto be a complete cessation of accretion, a phenomenon that has been observedonly once before in an intermediate polar. Simultaneous ground-basedobservations of this faint state establish that when accretion is negligible,YY Dra fades to $g=17.37\pm0.12$, which we infer to be the magnitude of thecombined photospheric contributions of the white dwarf and its red dwarfcompanion. Using survey photometry, we identify additional low states in2018-2019 during which YY Dra repeatedly fades to -- but never below -- thisthreshold. This implies relatively frequent cessations in accretion.Spectroscopic observations during future episodes of negligible accretion canbe used to directly measure the field strength of the white dwarf by Zeemansplitting. Separately, we search newly available catalogs of variable stars inan attempt to resolve the long-standing dispute over the proper identifier ofthis system.

Hitting a New Low: The Unique 28 h Cessation of Accretion in the TESS Light Curve of YY Dra (DO Dra)