相关论文: A User-Friendly Code to Diagnose Chromospheric Pla…
[abridged] Inversion techniques are the most powerful methods to obtain information about the thermodynamical and magnetic properties of solar and stellar atmospheres. In the last years, we have witnessed the development of highly…
The observation of the polarization emerging from a rotating star at different phases opens up the possibility to map the magnetic field in the stellar surface thanks to the well-known Zeeman Doppler Imaging. When the magnetic field is…
The ability of new instruments for providing accurate inferences of vector magnetic fields and line-of-sight velocities of the solar plasma depends a great deal on the sensitivity to these physical quantities of the spectral lines chosen to…
A large set of high precision full-Stokes spectropolarimetric observations of the He-D3 line in spicules has been recorded with the ZIMPOL polarimeter at the Gregory-Coude Telescope in Locarno. The observational technique allow us to obtain…
Spectral inversion codes are powerful tools to analyze spectropolarimetric observations, and they provide important diagnostics of solar magnetic fields. Inversion codes differ by numerical procedures, approximations of the atmospheric…
Scattering polarization tends to dominate the linear polarization signals of the Ca II 8542 A line in weakly magnetized areas ($B \lesssim 100$ G), especially when the observing geometry is close to the limb. In this paper we evaluate the…
Stokes inversion codes are crucial in returning properties of the solar atmosphere, such as temperature and magnetic field strength. However, the success of such algorithms to return reliable values can be hindered by the presence of…
The spectral line polarization encodes a wealth of information about the thermal and magnetic properties of the solar atmosphere. Modeling the Stokes profiles of strong resonance lines is, however, a complex problem both from the…
First results of the inversion of Stokes I and V profiles from plage regions near disk center are presented. Both low and high spatial resolution spectra of FeI 6301.5 and FeI 6302.5 A obtained with the Advanced Stokes Polarimeter (ASP)…
A large set of high precision full-Stokes spectropolarimetric observations of prominences in He-D3, Halpha and Hbeta lines has been recorded with the ZIMPOL polarimeter at the Gregory-Coude Telescope in Locarno. The observational technique…
Linearly polarized emission is described, in general, in terms of the Stokes parameters $Q$ and $U$, from which the polarization intensity and polarization angle can be determined. Although the polarization intensity and polarization angle…
Observational astrophysics started when spectroscopy could be applied to astronomy. Similarly, observational work on stellar magnetic fields became possible with the application of spectro-polarimetry. In recent decades there have been…
We describe a simple technique for the acceleration of spectro-polarimetric inversions based on principal component analysis (PCA) of Stokes profiles. This technique involves the indexing of the database models based on the sign of the…
Our knowledge of the lower solar atmosphere is mainly obtained from spectropolarimetric observations, which are often carried out in the red or infrared spectral range and almost always cover only a single or a few spectral lines. Here we…
The determination of the magnetic filed vector in solar filaments is possible by interpreting the Hanle and Zeeman effects in suitable chromospheric spectral lines like those of the He I multiplet at 10830 A. We study the vector magnetic…
Inversion techniques (ITs) allow us to infer the magnetic, dynamic, and thermal properties of the solar atmosphere from polarization line profiles. In recent years, major progress has come from the application of ITs to state-of-the-art…
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…
Electric currents play an important role in the energy balance of the plasma in the solar atmosphere. They are also indicative of non-potential magnetic fields and magnetic reconnection. Unfortunately, the direct measuring of electric…
The inference of the underlying state of the plasma in the solar chromosphere remains extremely challenging because of the nonlocal character of the observed radiation and plasma conditions in this layer. Inversion methods allow us to…
The solar chromosphere is a vigorously dynamic region of the sun, where waves and magnetic fields play an important role. To improve chromospheric diagnostics, we present new observations in Ca II 8542 carried out with the SST/CRISP on La…