Search Publications
Properties of solar plage from a spatially coupled inversion of Hinode SP data
Solanki, S. K.; Lagg, A.; van Noort, M. +1 more
Aims: The properties of magnetic fields forming an extended plage region in AR 10953 were investigated.
Methods: Stokes spectra of the Fe I line pair at 6302 Å recorded by the spectropolarimeter aboard the Hinode satellite were inverted using the SPINOR code. The code performed a 2D spatially coupled inversion on the Stokes spectra, allo…
Depth-dependent global properties of a sunspot observed by Hinode using the Solar Optical Telescope/Spectropolarimeter
Lagg, Andreas; Solanki, Sami K.; Tiwari, Sanjiv K. +1 more
Context. For the past two decades, the three-dimensional structure of sunspots has been studied extensively. A recent improvement in the Stokes inversion technique prompts us to revisit the depth-dependent properties of sunspots.
Aims: In the present work, we aim to investigate the global depth-dependent thermal, velocity, and magnetic proper…
Physical properties of solar polar jets. A statistical study with Hinode XRT data
Bemporad, A.; Sterling, A. C.; Paraschiv, A. R.
Aims: The target of this work is to investigate the physical nature of polar jets in the solar corona and their possible contribution to coronal heating and solar wind flow based on the analysis of X-ray images acquired by the Hinode XRT telescope. We estimate the different forms of energy associated with many of these small-scale eruptions, …
The evolution of the emission measure distribution in the core of an active region
Del Zanna, Giulio; Tripathi, Durgesh; Mason, Helen +2 more
We study the spatial distribution and evolution of the slope of the emission measure (EM) between 1 MK and 3 MK in the core of the active region (AR) NOAA 11193, first when it appeared near the central meridian and then again when it reappeared after a solar rotation. We use observations recorded by the Extreme-ultraviolet Imaging Spectrometer (EI…
Spatial deconvolution of spectropolarimetric data: an application to quiet Sun magnetic elements
Ruiz Cobo, B.; Quintero Noda, C.; Orozco Suárez, D. +1 more
Context. One of the difficulties in extracting reliable information about the thermodynamical and magnetic properties of solar plasmas from spectropolarimetric observations is the presence of light dispersed inside the instruments, known as stray light.
Aims: We aim to analyze quiet Sun observations after the spatial deconvolution of the data…
A distinct magnetic property of the inner penumbral boundary. Formation of a stable umbra-penumbra boundary in a sunspot
Jurčák, J.; Bello González, N.; Schlichenmaier, R. +1 more
Context. A sunspot emanates from a growing pore or protospot. In order to trigger the formation of a penumbra, large inclinations at the outskirts of the protospot are necessary. The penumbra develops and establishes by colonising both umbral areas and granulation. Evidence for a unique stable boundary value for the vertical component of the magne…
A solar tornado observed by EIS. Plasma diagnostics
Fletcher, L.; Schmieder, B.; Labrosse, N. +1 more
Context. The term "solar tornadoes" has been used to describe apparently rotating magnetic structures above the solar limb, as seen in high resolution images and movies from the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO). These often form part of the larger magnetic structure of a prominence, however the links b…
The photospheric solar oxygen project. III. Investigation of the centre-to-limb variation of the 630 nm [O I]-Ni I blend
Steffen, M.; Schmidt, W.; Ludwig, H. -G. +5 more
Context. The solar photospheric abundance of oxygen is still a matter of debate. For about ten years some determinations have favoured a low oxygen abundance which is at variance with the value inferred by helioseismology. Among the oxygen abundance indicators, the forbidden line at 630 nm has often been considered the most reliable even though it…
Alfvénic waves in polar spicules
Koutchmy, S.; Ahangarzadeh Maralani, A. R.; Tavabi, E. +2 more
Context. For investigating spicules from the photosphere to coronal heights, the new Hinode/SOT long series of high-resolution observations from space taken in CaII H line emission offers an improved way to look at their remarkable dynamical behavior using images free of seeing effects. They should be put in the context of the huge amount of alrea…
Spectroscopic observations and modelling of impulsive Alfvén waves along a polar coronal jet
Srivastava, A. K.; Murawski, K.; Dwivedi, B. N. +2 more
Context. The magnetic reconnection in the solar corona results in impulsively generated Alfvén waves, which drive a polar jet.
Aims: Using the Hinode/EIS 2'' spectroscopic observations, we study the intensity, velocity, and full width at half maximum (FWHM) variations of the strongest Fe XII 195.12 Å line along the jet to find the signature o…