G. Vigeesh, O. Steiner, S. S. Hasan
The solar atmosphere is magnetically structured and highly dynamic. Owing to
the dynamic nature of the regions in which the magnetic structures exist, waves
can be excited in them. Numerical investigations of wave propagation in
small-scale magnetic flux concentrations in the magnetic network on the Sun
have shown that the nature of the excited modes depends on the value of plasma
beta (the ratio of gas to magnetic pressure) where the driving motion occurs.
Considering that these waves should give rise to observable characteristic
signatures, we have attempted a study of synthesized emergent spectra from
numerical simulations of magneto-acoustic wave propagation. We find that the
signatures of wave propagation in a magnetic element can be detected when the
spatial resolution is sufficiently high to clearly resolve it, enabling
observations in different regions within the flux concentration. The
possibility to probe various lines of sight around the flux concentration bears
the potential to reveal different modes of the magnetohydrodynamic waves and
mode conversion. We highlight the feasibility of using the Stokes-V asymmetries
as a diagnostic tool to study the wave propagation within magnetic flux
concentrations. These quantities can possibly be compared with existing and new
observations in order to place constraints on different wave excitation
mechanisms.
View original:
http://arxiv.org/abs/1104.4069
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