相关论文: Solving the paradox of the solar sodium D1 line po…
The linearly polarized spectrum of the solar limb radiation produced by scattering processes is of great diagnostic potential for exploring the magnetism of the solar atmosphere. This spectrum shows an impressive richness of spectral…
The symmetric peak observed in linear polarization in the core of the solar sodium D$_1$ line at 5896 \AA\ has remained enigmatic since its discovery nearly two decades ago. One reason is that the theory of polarized scattering has not been…
The D$_1$ enigma is an anomaly, which was first observed on the Sun as a symmetric polarization peak centered in the core of the sodium D$_1$ line that is expected to be intrinsically unpolarizable. To resolve this problem the underlying…
We demonstrate that the atomic alignment of the hyperfine-structure components of the ground level S$_{1/2}$ of Na {\sc i} and of the upper level P$_{1/2}$ of the D$_1$ line are practically negligible for magnetic strengths $B>10 \rm G$,…
We explain the linear polarization of the Ca II infrared triplet observed close to the edge of the solar disk. In particular, we demonstrate that the physical origin of the enigmatic polarizations of the 866.2 nm and 854.2 nm lines lies in…
This paper reviews some recent advances in the development and application of polarized radiation diagnostics to infer the mean magnetization of the quiet solar atmosphere, from the near equilibrium photosphere to the highly non-equilibrium…
One of the greatest challenges in solar and stellar physics in coming years will be to observe the Second Solar Spectrum with a spatial resolution significantly better than 1 arcsec. This type of scattering polarization observations would…
An accurate calculation of the total polarization charge density in a plasma is essential for a self-consistent determination of the electric field. Yet, for a magnetized plasma, there are two different polarization paradoxes that are…
The solar magnetic fields emerging from the photosphere into the chromosphere and corona are comprised of a combination of "closed" and "open" fields. The closed magnetic field lines are defined as those having both ends rooted in the solar…
The only way to obtain reliable empirical information on the intensity and topology of the weak magnetic fields of the quiet solar chromosphere is via the measurement and rigorous physical interpretation of polarization signals in…
The polarization of the Mg II h and k lines holds significant diagnostic potential for measuring chromospheric magnetic fields, which are crucial for understanding the physical processes governing the energy transport and dissipation in the…
I review some recent advances in methods to diagnose polarized radiation with which we may hope to explore the magnetism of the solar chromosphere and corona. These methods are based on the remarkable signatures that the radiatively induced…
We report on a detailed radiative transfer modeling of the observed scattering polarization in the H-alpha line, which allows us to infer quantitative information on the magnetization of the quiet solar chromosphere. Our analysis suggests…
The solar chromosphere is a transition layer between the cool, dense photosphere and the hot, rarefied corona. This boundary region plays a key role in regulating energy transport and structuring the magnetic field throughout the solar…
Solar magnetic fields leave their fingerprints in the polarization signatures of the emergent spectral line radiation. This occurs through a variety of rather unfamiliar physical mechanisms, not only via the Zeeman effect. In particular,…
Polarimetric radio observations of the Sun can provide rich information about emission mechanisms and the propagation medium. For the past five decades, solar polarimetric studies at low radio frequencies have almost always assumed the…
This paper reviews some of the developments that over the last 10 years have allowed us to go from deciphering the physical origin of several of the enigmatic features of the second solar spectrum to discovering unknown aspects of the Sun's…
Deciphering and understanding the small-scale magnetic activity of the quiet solar photosphere should help to solve many of the key problems of solar and stellar physics, such as the magnetic coupling to the outer atmosphere and the coronal…
We employ the magnetic and velocity fields from turbulent dynamo simulations to synthesize the polarization of a typical photospheric line. The synthetic Stokes profiles have properties in common with those observed in the quiet Sun. The…
The morphology of spectral line polarization is the most valuable observable to investigate the magnetic and dynamic solar atmosphere. However, in order to develop solar diagnosis, it is fundamental to understand the different kinds of…