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		| Paper: | 
		Morphologies of Dusty Circumstellar Environments | 
	 
	
		| Volume: | 
		154, Cool Stars, Stellar Systems and the Sun: Tenth Cambridge Workshop | 
	 
	
		| Page: | 
		2057 | 
	 
	
		| Authors: | 
		Tuthill, Peter; Monnier, John; Danchi, William; Haniff, Chris | 
	 
	
	
		| Abstract: | 
		We present preliminary results from a program of near-IR diffraction-limited imaging of late-type stars underway at the Keck Observatory. Utilizing the techniques of aperture masking, we transformed the 10 m Keck primary mirror into a separate-element, multiple aperture interferometer. Evolved stars make particularly attractive targets for such a program as they exhibit bright extended emission in the IR which results from astrophysically interesting and poorly understood phenomena such as mass-loss and atmospheric extension. By imaging the hottest regions of circumstellar dust shells at unprecedented angular resolution, we have been able to observe the stellar morphology revealing anisotropic mass-loss in the inner regions where dust nucleation occurs. Furthermore, observations with the Keck telescope have yielded near-IR diameters and images of the stellar photospheres of nearby red giant and supergiants. | 
	 
	
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