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		| Paper: | 
		Investigating the Formation of the Helium Spectrum in the Solar Atmosphere | 
	 
	
		| Volume: | 
		154, Cool Stars, Stellar Systems and the Sun: Tenth Cambridge Workshop | 
	 
	
		| Page: | 
		559 | 
	 
	
		| Authors: | 
		Andretta, Vincenzo; Jordan, Stuart D.; Muglach, Karin; Garcia, Adriana; Jones, Harrison P.; Soltau, Dirk | 
	 
	
	
		| Abstract: | 
		We present the first results of coordinated observations with SOHO (Solar Heliospheric Observatory) and ground-based observatories aimed at investigating the mechanisms responsible for the formation of helium lines in the quiescent solar atmosphere. The observations described here were taken on 7-13 May 1997; the SOHO instruments involved were CDS, SUMER and EIT, while ground-based support was provided by the German Vacuum Tower Telescope on Tenerife (He 1 lambda10830 and Ca 2 lambda8498 spectra-spectroheliograms), Coimbra Solar Observatory (Hα spectroheliograms), and NASA/NSO Vacuum Tower Telescope on Kitt Peak (Ca 2 lambda8542 spectra-spectroheliograms and polarimetry). | 
	 
	
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