Related papers: Statistical Analysis of Magnetic Patches in Solar …
Using an efficient magnetic complexity index in the active-region solar photosphere, we quantify the preflare strength of the photospheric magnetic polarity inversion lines in 23 eruptive active regions with flare/CME/ICME events tracked…
Solar granulation consists of dynamic convective plasma cells that rise from the solar interior to the surface. The interaction between these plasma cells and the Sun's magnetic field provides valuable insights into plasma dynamics near the…
A qualitative analysis is given to the data on the full magnetic and velocity vector fields in a growing sunspot group, recorded nearly simultaneously with the Solar Optical Telescope on the Hinode satellite. Observations of a young bipolar…
Efficient prediction of solar flares relies on parameters that quantify the eruptive capability of solar active regions. Several such quantitative predictors have been proposed in the literature, inferred mostly from photospheric…
The \textit{Sun Watcher using Active Pixel system detector and Image Processing}(SWAP) on board the \textit{PRoject for OnBoard Autonomy\todash 2} (PROBA\todash 2) spacecraft provides images of the solar corona in EUV channel centered at…
Solar flares and coronal mass ejections are among the most prominent manifestations of the magnetic activity of the Sun. The strongest events of them tend to occur in active regions (ARs) that are large, complex, and dynamically evolving.…
We present high-cadence observations and simulations of the solar photosphere, obtained using the Rapid Oscillations in the Solar Atmosphere imaging system and the MuRAM magneto-hydrodynamic code, respectively. Each dataset demonstrates a…
We explore the general properties of near-surface flows around solar active regions. Helioseismic holography is applied to HMI Dopplergrams yielding nearly 5000 flow measurements of 336 unique active regions observed by the Solar Dynamics…
We study chromospheric oscillations including umbral flashes and running penumbral waves in a sunspot of active region (AR) using scanning spectroscopy in H-alpha and Ca II 8542A, with the Fast Imaging Solar Spectrograph (FISS) at the 1.6…
Small scale magnetic fields can be observed on the Sun in G-band filtergrams as MBPs (magnetic bright points) or identified in spectro-polarimetric measurements due to enhanced signals of Stokes profiles. These magnetic fields and their…
The sunspots and other solar activity indicators tend to cluster on the surface of the Sun.These clusters very often occur at certain longitudes that persist in time.It is of general interest to find new and simple ways to characterize the…
We have been monitoring yearly variation in the Sun's polar magnetic fields with the Solar Optical Telescope aboard {\it Hinode} to record their evolution and expected reversal near the solar maximum. All magnetic patches in the magnetic…
The emergence of dipolar magnetic features on the solar surface is an idealization. Most of the magnetic flux emergence occurs in complex multipolar regions. Here, we show that the surface pattern of magnetic structures alone can reveal the…
We have performed numerical magnetohydrodynamic (MHD) simulations of two closed active regions (AR). The input magnetic field values were the coronal magnetic field computed as extrapolation coronal from observations of the photospheric…
Parker Solar Probe and Solar Orbiter data are used to investigate the radial evolution of magnetic turbulence between $0.06 ~ \lesssim R ~\lesssim 1$ au. The spectrum is studied as a function of scale, normalized to the ion inertial scale…
This first paper in a series describes the design of a study testing whether pre-appearance signatures of solar magnetic active regions were detectable using various tools of local helioseismology. The ultimate goal is to understand…
The magnetic topology of the solar photosphere in its quietest regions is hidden by the difficulties to disentangle magnetic flux through the resolution element from the field strength of unresolved structures. The observation of spectral…
We applied automatic identification of sunspot umbrae and penumbrae to daily observations from the Helioseismic Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) to study their magnetic flux (B) and area (A). The results…
Solar flares originate from magnetically active regions but not all solar active regions give rise to a flare. Therefore, the challenge of solar flare prediction benefits by an intelligent computational analysis of physics-based properties…
In the solar corona, magnetic helicity slowly and continuously accumulates in response to plasma flows tangential to the photosphere and magnetic flux emergence through it. Analyzing this transfer of magnetic helicity is key for identifying…