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		| Paper: | 
		Molecular Hydrogen Emission from the Photodissociation Region in Hubble 12 | 
	 
	
		| Volume: | 
		132, Star Formation with the Infrared Space Observatory (ISO) | 
	 
	
		| Page: | 
		330 | 
	 
	
		| Authors: | 
		Chrysostomou, Antonio; Brand, Peter W. J. L.; Ramsay Howat, Suzanne K.; Burton, Michael G. | 
	 
	
	
		| Abstract: | 
		Infrared spectra of molecular hydrogen (H_2) line emission, from the photodissociation region in the planetary nebula Hubble 12, are presented. The spectra range between 0.7 and 2.5 microns. Approximately 75 H_2 lines were measured with over 100 lines actually detected. The ortho/para ratio for H_2 was measured and it is shown that there is a decreasing trend in this ratio with energy level. This is qualitatively interpreted as the radiative excitation of `fresh' molecules from the molecular cloud by a still evolving and young photodissociation region. | 
	 
	
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