10 MICRON IMAGING OF UZ TAURI - EVIDENCE FOR CIRCUMSTELLAR DISK CLEARING DUE TO A CLOSE COMPANION STAR

We present 10 mum images of the multiple T Tauri star system UZ Tau taken with the Berkeley mid-infrared array camera at UKIRT and evidence that UZ Tau E and W are a common proper pair. The mid-infrared emission is resolved for the first time into the two components UZ Tau E and UZ Tau W. The mid-infrared excess deduced for UZ Tau W appears to be much lower than that observed for UZ Tau E. This excess emission is consistent with an optically thin circumstellar disk in the case of UZ Tau W, whereas UZ Tau E's excess is consistent with an optically thick disk. We suggest that the close binary star pair in UZ Tau W is responsible for the observed difference between UZ Tau E and W's mid-infrared excess. In the proposed model, the binary star interacts with the local circumstellar disk environment and clears out much of the material inside its orbital radius (approximately 50 AU). As a result, the hot dust, observed at mid-infrared wavelengths, in UZ Tau W is suppressed compared to its ''wider'' companion UZ Tau E. This scenario can also plausibly account for differences observed in UZ Tau E's and UZ Tau W's optical line strengths and profiles.