LOCAL HELIOSEISMIC AND SPECTROSCOPIC ANALYSES OF INTERACTIONS BETWEEN ACOUSTIC WAVES AND A SUNSPOT

@article{Rajaguru2010LOCALHA,
  title={LOCAL HELIOSEISMIC AND SPECTROSCOPIC ANALYSES OF INTERACTIONS BETWEEN ACOUSTIC WAVES AND A SUNSPOT},
  author={S. P. Rajaguru and Richard Wachter and Kasiviswanathan Sankarasubramanian and S. Couvidat Indian Institute of Astrophysics and Bangalore and India Hansen Experimental Physics Laboratory and Stanford University and Stanford and Ca and Usa Space Science Division and Space Astronomy Group and Isro Satellite Centre and India.},
  journal={The Astrophysical Journal},
  year={2010},
  volume={721}
}
Using a high-cadence imaging spectropolarimetric observation of a sunspot and its surroundings in magnetically sensitive (Fe I 6173 A) and insensitive (Fe I 7090 A) upper photospheric absorption lines, we map the instantaneous wave phases and helioseismic travel times as a function of observation height and inclination of magnetic field to the vertical. We confirm the magnetic inclination-angle-dependent transmission of incident acoustic waves into upward propagating waves and derive (1) proof… Expand

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