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		| Paper: | 
		An Isolated HII Region near ESO 481-G017 | 
	 
	
		| Volume: | 
		423, Galaxy Wars: Star Formation and Stellar Populations in Interacting Galaxies | 
	 
	
		| Page: | 
		48 | 
	 
	
		| Authors: | 
		Santiago-Figueroa, N.; Putman, M.; Werk, J.; Ryan-Weber, E.; Meurer, G. | 
	 
	
	
		| Abstract: | 
		We obtained VLA 21-cm observations of the galaxy ESO 481-G017 to determine the environment and trigger of remote star formation traced by an HII region found 43 kpc from the galaxy (in projection). ESO 481-G017 is an early type spiral galaxy with a HI mass of 1.1×109 Msun and a distance of 55 Mpc. The isolated HII region has a Hα luminosity of 1038.1 erg s-1 and minimal continuum emission suggesting that new stars have formed where little or no stars previously existed. The difference in velocity between the HI disk of ESO 481-G017 ( 3840-4000 km s-1 ) and the isolated HII region ( 4701± 80 km s-1 ) indicates the origin of the HII region may be stars forming in a tidal feature or newly triggered star formation in a very low luminosity companion galaxy. The VLA observations shed light on the nature of this young object. | 
	 
	
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