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		| Paper: | 
		Impact of pulsation on the structure of circumstellar envelopes | 
	 
	
		| Volume: | 
		11, Confrontation Between Stellar Pulsation and Evolution | 
	 
	
		| Page: | 
		427 | 
	 
	
		| Authors: | 
		Heske, Astrid | 
	 
	
	
		| Abstract: | 
		Correlations between the stellar parameters and circumstellar parameters of long-period variables are discussed, and a strong influence of the period on the structure of the circumstellar envelope is established. Observational results along with nonregular period variations detected during monitoring observations are used for exploring a model based on a perturbed Keplerian oscillator, in which the star is composed of two oscillators: the interior acting as the driving oscillator and the mantle representing the driven oscillator. It is demonstrated that period variations and long-term amplitude are the generic features of the driven oscillator, and that the initial conditions are critical for the behavior of the mantle. | 
	 
	
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