Bibcode
Katsukawa, Y.; Orozco-Suárez, D.
Bibliographical reference
The Astrophysical Journal, Volume 758, Issue 2, article id. 139, 9pp, (2012).
Advertised on:
10
2012
Journal
Citations
20
Refereed citations
20
Description
We have performed power spectral analysis of surface temperatures,
velocities, and magnetic fields, using spectropolarimetric data taken
with the Hinode Solar Optical Telescope. When we make power spectra in a
field of view covering the supergranular scale, kinetic and thermal
power spectra have a prominent peak at the granular scale while the
magnetic power spectra have a broadly distributed power over various
spatial scales with weak peaks at both the granular and supergranular
scales. To study the power spectra separately in internetwork and
network regions, power spectra are derived in small subregions extracted
from the field of view. We examine slopes of the power spectra using
power-law indices, and compare them with the unsigned magnetic flux
density averaged in the subregions. The thermal and kinetic spectra are
steeper than the magnetic ones at the subgranular scale in the
internetwork regions, and the power-law indices differ by about 2. The
power-law indices of the magnetic power spectra are close to or smaller
than –1 at that scale, which suggests the total magnetic energy
mainly comes from either the granular scale magnetic structures or both
the granular scale and smaller ones contributing evenly. The slopes of
the thermal and kinetic power spectra become less steep with increasing
unsigned flux density in the network regions. The power-law indices of
all the thermal, kinetic, and magnetic power spectra become similar when
the unsigned flux density is larger than 200 Mx cm–2.
Related projects
Magnetism, Polarization and Radiative Transfer in Astrophysics
Magnetic fields pervade all astrophysical plasmas and govern most of the variability in the Universe at intermediate time scales. They are present in stars across the whole Hertzsprung-Russell diagram, in galaxies, and even perhaps in the intergalactic medium. Polarized light provides the most reliable source of information at our disposal for the
Tanausú del
Pino Alemán