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		| Paper: | 
		The distribution of comets around stars | 
	 
	
		| Volume: | 
		36, Planets Around Pulsars | 
	 
	
		| Page: | 
		335 | 
	 
	
		| Authors: | 
		Tremaine, Scott | 
	 
	
	
		| Abstract: | 
		The distribution of comets around stars surrounded by planetary systems that formed from disks is analyzed. Results reveal that stars similar to the sun can only generate an Oort-type cloud efficiently if they contain planets at semimajor axis greater than approximately 3 AU. The typical semimajor axis in an Oort-type cloud around a solar-type star will be 10 exp 4 AU. Halo stars are found to require planets that are smaller by about a factor of 3 at a given semimajor axis, and produce larger cloud, with a semimajor axis of about 2 x 10 exp 4 AU. | 
	 
	
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