  RW Aur A is a classical T Tauri star, believed to have undergone a
reconfiguration of its circumstellar environment as a consequence of a recent
fly-by of its stellar companion, RW Aur B. This interaction stripped away part
of the circumstellar disk of RW Aur A, leaving a tidally disrupted arm and a
short truncated circumstellar disk. We present photometric observations of the
RW Aur system from the Kilodegree Extremely Little Telescope (KELT) survey
showing a long and deep dimming that occurred from September 2010 until March
2011. The dimming has a depth of ~2 magnitudes, a duration of ~180 days and was
confirmed by archival observations from American Association of Variable Star
Observers (AAVSO). We suggest that this event is the result of a portion of the
tidally disrupted disk occulting RW Aur A, specifically a fragment of the
tidally disrupted arm. The calculated transverse linear velocity of the
occulter is in excellent agreement with the measured relative radial velocity
of the tidally disrupted arm. Using simple kinematic and geometric arguments,
we show that the occulter cannot be a feature of the RW Aur A circumstellar
disk, and we consider and discount other hypotheses. We also place constraints
on the thickness and semi-major axis of the portion of the arm that occulted
the star.
