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Measurements of Acoustic Waves Scattered by Sunspots. Dean-Yi Chou. Collaborators:. Tsing Hua University, Taiwan. Hui Zhao Ming-Hsu Yang. (Stanford, April 2011, LoHCo Workshop). Waves Scattered by a Sunspot. Cameron et al. 2008. The incident wave is a plane wave packet.
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Measurements of Acoustic Waves Scattered by Sunspots Dean-Yi Chou Collaborators: Tsing Hua University, Taiwan Hui Zhao Ming-Hsu Yang (Stanford, April 2011, LoHCo Workshop)
Cameron et al. 2008 The incident wave is a plane wave packet. Cross-correlation between the reference line and each point
Data NOAA 11092 HMI: 30 July – 5 August 2010 (13,583 frames)
The cross-correlation function relates to the wave function, but is not the wave function!!!
Comparison of CCF and Wave • Initially, the wave is narrower than the CCF. • As it propagates, the width of wave increases faster than the width of CCF • because of dispersion.
Interference Patterns from total waves
A Phenomenological Model wave equation in QS σ describes magnetic regions wave equation with magnetic fields solution Green’s function If
Scattered Waves from a Model constant σ inside the circular area