Related papers: A comparison between solar plage and network prope…
The observation of propagating magneto-hydrodynamic kink waves in magnetic structures and measurement of their properties (amplitude, phase speed) can be used to diagnose the plasma conditions in the neighbourhood of the magnetic structure…
For groups of photospheric magnetic fields differing in strength the time averaged synoptic maps were obtained on the basis of the National Solar Observatory Kitt Peak data (1976-2003). The latitudinal profiles of magnetic field fluxes were…
We analyze spectropolarimetric observations of the chromospheric Ca II 8542 line taken by the Interferometric Bidimensional Spectrometer (IBIS) at the Dunn Solar Telescope and photospheric Fe I 6302 lines obtained with the Solar Optical…
A sunspot penumbra is observationally examined to reveal properties of small-scale flow structures and how they are related to the filamentary magnetic structures and the Evershed flow. We also study how the photospheric dynamics is related…
Observations of the polar region of the Sun are critically important for understanding the solar dynamo and the acceleration of solar wind. We carried out precise magnetic observations on both the North polar region and the quiet Sun at the…
Sunspots, faculae and the magnetic network contribute to solar irradiance variations. The contribution due to faculae and the network is of basic importance, but suffers from considerable uncertainty. We determine the contrasts of active…
The irradiance of the Sun is modulated on all time scales. Small-scale solar magnetic elements composed of quiet-Sun network and active region plages contribute to this modulation on solar cycle time scales. The evaluation of their contrast…
We investigated the role of photospheric plasma motions in the formation and evolution of polar magnetic patches using time-sequence observations with high spatial resolution. The observations were obtained with the spectropolarimeter on…
By use of the high-resolution spectral data and the broadband imaging obtained with the Goode Solar Telescope at the Big Bear Solar Observatory on 2013 June 6, the spectra of three typical photospheric bright points (PBPs) have been…
In this study we present simultaneous low-resolution longitudinal magnetic field measurements and high-resolution spectroscopic observations of the cool single giant FK Com. The variation of the magnetic field over the rotational period of…
Context: Observations indicate that the `quiet' solar photosphere outside active regions contains considerable amounts of magnetic energy and magnetic flux, with mixed polarity on small scales. The origin of this flux is unclear. Aims: We…
Some models for the topology of the magnetic field in sunspot penumbrae predict the existence of field-free or dynamically weak-field regions in the deep Photosphere. To confirm or rule out the existence of weak-field regions in the deepest…
Small-scale internetwork magnetic fields are important ingredients of the quiet Sun. In this paper we analyze how they appear and disappear on the solar surface. Using high resolution Hinode magnetograms, we follow the evolution of…
Our aim is to determine the plasma properties of a coronal bright point and compare its magnetic topology extrapolated from magnetogram data with its appearance in X-ray images. We analyse spectroscopic data obtained with EIS/Hinode, Ca II…
We demonstrate that the radial magnetic-field component at the outer boundary of the sunspot penumbra is about 550 Mx cm$^{-2}$ independent of the sunspot area and the maximum magnetic field in the umbra. The mean magnetic-field intensity…
We investigate the fine structure of magnetic fields in the atmosphere of the quiet Sun. We use photospheric magnetic field measurements from {\sc Sunrise}/IMaX with unprecedented spatial resolution to extrapolate the photospheric magnetic…
We study the radiative emission of various types of solar features, such as quiet Sun, enhanced network, plage, and bright plage regions, identified on filtergrams taken in the Ca II K line. We analysed fulldisk images obtained with the…
We use G-band and Ca II H image sequences from the Dutch Open Telescope (DOT) to study magnetic elements that appear as bright points in internetwork parts of the quiet solar photosphere and chromosphere. We find that many of these bright…
The fine-structure of magnetic field of a sunspot penumbra in the upper chromosphere is to be explored and compared to that in the photosphere. High spatial resolution spectropolarimetric observations were recorded with the 1.5-meter GREGOR…
Solar plages, which are bright regions on the Sun's surface, are an important indicator of solar activity. In this study, we propose an automated algorithm for identifying solar plages in Ca K wavelength solar data obtained from the…