Bibcode
Centeno, R.; Collados, M.; Trujillo Bueno, J.
Bibliographical reference
The Astrophysical Journal, Volume 692, Issue 2, pp. 1211-1220 (2009).
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2
2009
Journal
Citations
68
Refereed citations
65
Description
Velocity oscillations "measured" simultaneously at the photosphere and
the chromosphere—from time series of spectropolarimetric data in
the 10830 Å region—of different solar magnetic features
allow us to study the properties of wave propagation as a function of
the magnetic flux of the structure (i.e., two different-sized sunspots,
a tiny pore, and a facular region). While photospheric oscillations have
similar characteristics everywhere, oscillations measured at
chromospheric heights show different amplitudes, frequencies, and stages
of shock development depending on the observed magnetic feature. The
analysis of the power and the phase spectra, together with simple
theoretical modeling, lead to a series of results concerning wave
propagation within the range of heights of this study. We find that,
while the atmospheric cutoff frequency and the propagation properties of
different oscillating modes depend on the magnetic feature, in all the
cases the power that reaches the high chromosphere above the atmospheric
cutoff comes directly from the photosphere by means of linear vertical
wave propagation rather than from nonlinear interaction of modes.
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