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Related papers: Recent Advances in Chromospheric and Coronal Polar…

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The magnetic field vector of the solar corona is not regularly and comprehensively being measured, because of the complexity and degeneracy inherently present in the types of observations currently available. To address some of the current…

Solar and Stellar Astrophysics · Physics 2024-10-31 Momchil Molnar , Roberto Casini

Chromospheric magnetic fields are notoriously diffcult to measure. The chromospheric lines are broad, while the fields are producing a minuscule Zeeman-effect polarization. A promising diagnostic alternative is provided by the…

Solar and Stellar Astrophysics · Physics 2015-05-28 M. Bianda , R. Ramelli , L. S. Anusha , J. O. Stenflo , K. N. Nagendra , R. Holzreuter , M. Sampoorna , H. Frisch , H. N. Smitha

When observed in quiet regions close to the solar limb, many strong resonance lines show conspicuous linear polarization signals, produced by scattering processes, with extended wing lobes. Recent studies indicate that, contrary to what was…

Solar and Stellar Astrophysics · Physics 2022-01-12 Emilia Capozzi , Ernest Alsina Ballester , Luca Belluzzi , Javier Trujillo Bueno

In solar physics, it is a big challenge to measure the magnetic fields directly from observations in the upper solar atmosphere, including the chromosphere and corona. Radio observations are regarded as the most feasible approach to…

Solar and Stellar Astrophysics · Physics 2022-06-22 Baolin Tan

The physical interpretation of spectropolarimetric observations of lines of neutral helium, such as those of the 10830 A multiplet, represents an excellent opportunity for investigating the magnetism of plasma structures in the solar…

Astrophysics · Physics 2007-05-23 A. Asensio Ramos , J. Trujillo Bueno

Our understanding of coronal phenomena, such as coronal plasma thermodynamics, faces a major handicap caused by missing coronal magnetic field measurements. Several lines in the UV wavelength range present suitable sensitivity to determine…

Astrophysics · Physics 2008-01-16 N. -E. Raouafi , S. K. Solanki , T. Wiegelmann

This is a review of a decade-long effort to develop novel tools for exploring magnetism in cold astrophysical media and to establish a new field of molecular spectropolarimetry since Berdyugina et al. (2000). It is most directly applicable…

Solar and Stellar Astrophysics · Physics 2010-11-04 Svetlana V. Berdyugina

A major challenge in solar physics is to obtain empirical information on the magnetic field of the million-degree plasma of the solar corona. To this end, we need observables of the solar radiation sensitive to the coronal magnetic field.…

Due to the continuous developments in polarimetric instrumentation, which will become even more dramatic in the near future with the availability of new generation solar telescopes, we are now severely confronted with a variety of new…

Solar and Stellar Astrophysics · Physics 2011-03-29 Luca Belluzzi

Regular remote sensing of the magnetic field embedded within the million-degree solar corona is severely lacking. This reality impedes fundamental investigations of the nature of coronal heating, the generation of solar and stellar winds,…

Magnetic field diagnostics of the transition region from the chromosphere to the corona faces us with the problem that one has to apply extreme UV spectro-polarimetry. While for coronal diagnostic techniques already exist through infrared…

Solar and Stellar Astrophysics · Physics 2013-03-11 H. Peter

This paper focuses on the polarized profiles of resonance scattering lines that form in magnetized disks. Optically thin lines from Keplerian planar disks are considered. Model line profiles are calculated for simple field topologies of…

Solar and Stellar Astrophysics · Physics 2015-05-20 R. Ignace

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…

Astrophysics of Galaxies · Physics 2018-01-31 C. A. Herron , B. M. Gaensler , G. F. Lewis , N. M. McClure-Griffiths

The maturity of current detectors based on technologies that range from solid state to gases renewed the interest for X-ray polarimetry, raising the enthusiasm of a wide scientific community to improve the performance of polarimeters as…

Instrumentation and Methods for Astrophysics · Physics 2018-05-14 Sergio Fabiani

The polarization of radiation by scattering on an atom embedded in combined external quadrupole electric and uniform magnetic fields is studied theoretically. Analytic formulae are derived for the scattering phase matrix. Limiting cases of…

Astrophysics · Physics 2007-05-23 Yee Yee Oo , K. N. Nagendra , Sharath Ananthamurthy , G. Ramachandran

Magnetic fields in turbulent, convective high-$\beta$ plasma naturally develop highly tangled and complex topologies---the solar photosphere being the paradigmatic example. These fields are mostly undetectable by standard diagnostic…

This paper shows the first synthetic tomography of the quiet solar chromosphere formed by spatial maps of scattering polarization. It has been calculated for the CaII 8498, 8542 and 3934 A lines by solving the NLTE (non-local…

Solar and Stellar Astrophysics · Physics 2015-06-23 E. S. Carlin , A Asensio Ramos

Observations of scattering polarization and the Hanle effect in various spectral lines are increasingly used to complement traditional solar magnetic field determination techniques. One of the strongest scattering polarization signals in…

Solar and Stellar Astrophysics · Physics 2022-06-15 Franziska Zeuner , Luca Belluzzi , Nuno Guerreiro , Renzo Ramelli , Michele Bianda

The Hanle effect in strong spectral lines is the physical mechanism that should be increasingly exploited for quantitative explorations of the magnetism of the quiet solar chromospheric plasma. Here we show, by means of multilevel radiative…

Solar and Stellar Astrophysics · Physics 2011-02-25 Jiri Stepan , Javier Trujillo Bueno , Renzo Ramelli , Michele Bianda

Magnetic fields are the primary driver of the plasma thermodynamics in the upper solar atmosphere, especially in the corona. However, magnetic field measurements in the solar corona are sporadic, thereby limiting us from the complete…

Solar and Stellar Astrophysics · Physics 2024-06-12 Raveena Khan , Sarah E. Gibson , Roberto Casini , K. Nagaraju