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		| Paper: | 
		Seismology of Flaring and Dormant Active Regions | 
	 
	
		| Volume: | 
		478, Fifty Years of Seismology of the Sun and Stars | 
	 
	
		| Page: | 
		231 | 
	 
	
		| Authors: | 
		Maurya, R. A. | 
	 
	
	
		| Abstract: | 
		We study photospheric and sub-photospheric properties of active and quiet regions observed during 11 – 17 February 2011 including the first X-class flare X2.2 of the solar cycle 24 which occurred in the active region NOAA 11158 on 15 February 2011. The p-mode parameters and sub-photospheric flows are computed from the ring-diagrams and inversions. We found larger frequency shifts in active regions than quiet regions. The active region NOAA 11158 shows stronger twisted sub-photospheric flows than dormant active regions. The kinetic helicity density of sub-photospheric flows of the active region NOAA 11158 shows different structure on the flare day than the pre- and post-flare days. | 
	 
	
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