Abstract Details
| Name: Tanmoy Samanta Affiliation: Indian Institute of Astrophysics Conference ID: ASI2015_412 Title : Study of the wave propagation and reflection in the Solar atmosphere using multi-wavelength observations Authors and Co-Authors : Henriques, V. M. J.: Queens University; Banerjee, D. : Indian Institute of Astrophysics; Mathioudakis, M: Queens University Abstract Type : Poster Abstract Category : Sun and the Solar System Abstract : The trapped acoustic waves (p-modes) inside the Sun can leak from the surface and propagate through the atmosphere if periods are shorter than 3 minutes, known as the acoustic cut-off period, longer periods do not propagate at greater heights in the chromosphere and are, instead, evanescent. But the presence of relatively strong magnetic fields can create magneto-acoustic portals which channel the long-period waves into the upper atmosphere. We have observed a quit Sun region with Swedish 1-meter Solar Telescope (SST) using an Imaging SpectroPolarimeter (CRISP). High resolution, high cadence, line scanning images were taken in different layers from Photosphere to upper Chromosphere. In power maps of the upper photosphere and the lower chromosphere one can identify suppressed power surrounding the magnetic network elements, known as magnetic shadow. Our analysis also shows that the wave with periods above the acoustic cut-off propagate from the photosphere to upper layers only in restricted areas in presence of magnetic filed. This supports recent results arguing that network magnetic elements can channel low-frequency photospheric oscillations into the chromosphere, thus providing a way to input mechanical energy in the upper layers. We conclude that the magnetic shadow is linked to the wave mode conversion process which depend on magnetic field topology at the region. |