Related papers: Two New Methods for Counting and Tracking the Evol…
Although the Sun's polar magnetic fields are thought to provide important clues for understanding the 11-year sunspot cycle, including the observed variations of its amplitude and period, the current database of high-quality polar-field…
In a previous paper, I described a new way of determining the high-latitude solar rotation rate statistically from space-time maps of polar faculae observed in the 6767 \r{A} continuum by the Michelson Doppler Interferometer (MDI) on the…
The magnetic properties of the Sun's polar faculae are investigated with spectropolarimetric observations of the north polar region obtained by the Hinode satellite in 2007 September. Polar faculae are embedded in nearly all magnetic…
Polar faculae are bright features that can be detected in solar limb observations and they are related to magnetic field concentrations. Although there is a large number of works studying them, some questions about their nature as their…
Surfaces of the Sun and other cool stars are filled with magnetic fields, which are either seen as dark compact spots or more diffuse bright structures like faculae. Both hamper detection and characterisation of exoplanets, affecting…
Polar Crown Filaments (PCFs) form above the magnetic polarity inversion line, which separates the unipolar polar fields and the nearest dispersed fields from trailing part of active regions with opposite polarity. The statistical properties…
This paper describes a new way of determining the high-latitude solar rotation rate statistically from simultaneous observations of many polar faculae. In this experiment, I extracted frames from a movie made previously from flat-fielded…
Rotational periods derived from autocorrelation (ACF) techniques on stars photometrically similar to the Sun in Kepler data have proven difficult to reliably determine. We investigate various instrumental and astrophysical factors affecting…
Small-scale magnetic flux concentrations contribute significantly to the brightness variations of the Sun, yet observing them - particularly their magnetic field - near the solar limb remains challenging. Solar Orbiter offers an…
Regular spaceborne measurements have revealed that solar brightness varies on multiple timescales, variations on timescales greater than a day being attributed to surface magnetic field. Independently, ground-based and spaceborne…
Oscillation properties in two sunspots and two facular regions are studied using Solar Dynamics Observatory (SDO) data and ground-based observations in the SiI 10827 and HeI 10830 lines. The aim is to study different-frequency spatial…
Context. Stellar spectral variability on timescales of a day and longer, arising from magnetic surface features such as dark spots and bright faculae, is an important noise source when characterising extra-solar planets. Current 1D models…
We report on the photometric properties of faculae and network as observed in full-disk, scattered-light corrected images from the Helioseismic Magnetic Imager. We use a Lucy-Richardson deconvolution routine that corrects an image in less…
Light curves of solar-type stars often show gradual fluctuations due to rotational modulation by magnetic features (starspots and faculae) on stellar surfaces. Two quantitative measures of modulated light curves are employed as the proxies…
Magnetic features on the surface of stars, such as spots and faculae, cause stellar spectral variability on time-scales of days and longer. For stars other than the Sun, the spectral signatures of faculae are poorly understood, limiting our…
This study aims at setting observational constraints on the continuum and line core intensity contrast of network and faculae, specifically, their relationship with magnetic field and disc position. Full-disc magnetograms and intensity…
Taken at a high spatial resolution of 0.1 arcsec, Bright Points (BPs) are found to coexist with faculae in images and the latter are often resolved as adjacent striations. Understanding the properties of these different features is…
For solar activity cycles 20 and 21 (1966-1985) the solar differential rotation has been investigated using H{\alpha} filaments and relatively small-scale long-lived magnetic features with negative and positive polarities. We used annual…
Spicules are small hairy like structures seen at the solar limb mainly at chromospheric and transition region lines. They generally live for 3-10 minutes. We observe these spicules in a south polar region of the Sun with a coordinated…
We study the properties of waves in a facular region of moderate strength in the photosphere and chromosphere. Our aim is to analyse statistically the wave periods, power and phase relations as a function of the magnetic field strength and…