Search Publications
High-precision density measurements in the solar corona. I. Analysis methods and results for Fe XII and Fe XIII
Young, P. R.; Mariska, J. T.; Hara, H. +1 more
Aims: The EUV Imaging Spectrometer (EIS) instrument on board the Hinode satellite has access to some of the best coronal density diagnostics, and the high sensitivity of the instrument now allows electron number density, N_e, measurements to an unprecedented precision of up to ±5% in active regions. This paper gives a thorough overview of data ana…
Hinode/EIS observations of propagating low-frequency slow magnetoacoustic waves in fan-like coronal loops
Wang, T. J.; Davila, J. M.; Mariska, J. T. +1 more
Aims: We report the first observation of multiple-periodic propagating disturbances along a fan-like coronal structure simultaneously detected in both intensity and Doppler shift in the Fe xii 195 Å line with the EUV Imaging Spectrometer (EIS) onboard Hinode. A new application of coronal seismology is provided based on this observation.
Method…
Upward propagating high-frequency Alfvén waves as identified from dynamic wave-like spicules observed by SOT on Hinode
Tu, C. -Y.; Marsch, E.; Tian, H. +3 more
Aims: We identify high-frequency Alfvén waves propagating upward in the solar chromosphere and transition region from observation by Solar Optical Telescope (SOT) onboard Hinode.
Methods: The spicule shape is enhanced through application of a normal radial gradient filter and an un-sharp mask on the images taken by SOT. The displaced position …
Comparison of transient horizontal magnetic fields in a plage region and in the quiet Sun
Ishikawa, R.; Tsuneta, S.
Aims: The properties of transient horizontal magnetic fields (THMFs) in both plage and quiet Sun regions are obtained and compared.
Methods: Spectro-polarimetric observations with the Solar Optical Telescope (SOT) on the Hinode satellite were carried out with a cadence of about 30 s for both plage and quiet regions located near the disk center…
Signatures of Alfvén waves in the polar coronal holes as seen by EIS/Hinode
Doyle, J. G.; Banerjee, D.; Pérez-Suárez, D.
Context: We diagnose the properties of the plume and interplume regions in a polar coronal hole and the role of waves in the acceleration of the solar wind.
Aims: We attempt to detect whether Alfvén waves are present in the polar coronal holes through variations in EUV line widths.
Methods: Using spectral observations performed over a pola…
On the continuum intensity distribution of the solar photosphere
Rouppe van der Voort, L.; Wedemeyer-Böhm, S.
Context: For many years, there seemed to be significant differences between the continuum intensity distributions derived from observations and simulations of the solar photosphere.
Aims: In order to settle the discussion on these apparent discrepancies, we present a detailed comparison between simulations and seeing-free observations that tak…
Evidence of photospheric vortex flows at supergranular junctions observed by FG/SOT (Hinode)
Innes, D. E.; Potts, H. E.; Attie, R.
Context: Twisting motions of different sorts are observed in several layers of the solar atmosphere. Chromospheric sunspot whorls and rotation of sunspots or even higher up in the lower corona sigmoids are examples of the large-scale twisted topology of many solar features. Nevertheless, their occurrence on a large scale in the quiet photosphere h…
Small-scale oscillations in a quiescent prominence observed by HINODE/SOT. Prominence oscillations
Ichimoto, K.; Cao, W.; Qu, Z. Q. +2 more
Context: Investigations of the behavior of small-scale threads can provide an alternative approach to studying prominence dynamics and understanding its origin and nature.
Aims: The behavior of threads are analyzed in a quiescent prominence, including drifting and both the horizontally and vertically oscillating motions. These indicate waves i…
Magnetic flux emergence into the solar photosphere and chromosphere
Moreno-Insertis, F.; Tortosa-Andreu, A.
Aims: We model the emergence of magnetized plasma across granular convection cells and the low atmosphere, including layers up to the mid-chromosphere.
Methods: Three-dimensional numerical experiments are carried out in which the equations of MHD and radiative transfer are solved self-consistently. We use the MURaM code, which assumes local th…
The size distribution of magnetic bright points derived from Hinode/SOT observations
Möstl, C.; Veronig, A.; Utz, D. +3 more
Context: Magnetic bright points (MBPs) are small-scale magnetic features in the solar photosphere. They may be a possible source of coronal heating by rapid footpoint motions that cause magnetohydrodynamical waves. The number and size distribution are of vital importance in estimating the small scale-magnetic-field energy.
Aims: The size distr…