A magnetic field modifies the properties of waves in a complex way. Significant advances have been made recently in our understanding of the physics of sunspot...
Oscillations in the Photosphere of a Sunspot Umbra from the Inversion of Infrared Stokes Profiles
We report on the detection of magnetic field strength and velocity oscillations in the photosphere of a sunspot umbra. Our analysis is based on the inversion of...
A set of series of spectra of high spectral resolution corresponding to the same umbra on several days, is used to study the oscillations related to evolution...
Penumbral thermal structure below the visible surface
Context. The thermal structure of the penumbra below its visible surface (i.e., τ5 ≥ 1) has important implications for our present understanding of sunspots and...
Performance of solar far-side active region neural detection
Context. Far-side helioseismology is a technique used to infer the presence of active regions in the far hemisphere of the Sun based on the interpretation of...
Phase diversity restoration of sunspot images. I. Relations between penumbral and photospheric features
We investigate the dynamics of and the relations between small-scale penumbral and photospheric features near the outer penumbral boundary: penumbral grains...
Phase diversity restoration of sunspot images. II. Dynamics around a decaying sunspot
Two time series, taken simultaneously in the G-band and in white-light, and corrected for telescope aberrations and turbulence perturbations using the method of...
The decay of a sunspot region was studied using high resolution white-light pictures. The photometric and geometric parameters of a light-bridge showing...