English
Related papers

Related papers: Spectral resolution effects on the information con…

200 papers

When inverting solar spectra, image degradation effects that are present in the data are usually approximated or not considered. We develop a data reduction method that takes these issues into account and minimizes the resulting errors. By…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 M. van Noort

Quantitative thermodynamical, dynamical and magnetic properties of the solar and stellar plasmas are obtained by interpreting their emergent non-polarized and polarized spectrum. This inference requires the selection of a set of spectral…

Solar and Stellar Astrophysics · Physics 2016-05-25 A. Asensio Ramos , J. de la Cruz Rodriguez , M. J. Martinez Gonzalez , A. Pastor Yabar

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…

Solar and Stellar Astrophysics · Physics 2015-06-04 H. Balthasar , M. L. Demidov

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…

Instrumentation and Methods for Astrophysics · Physics 2019-01-30 T. L. Riethmüller , S. K. Solanki

Imaging spectrographs are popular instruments used to obtain solar data. They record quasi-monochromatic images at selected wavelength positions. By scanning the spectral range of the line, it is possible to obtain bidimensional maps of the…

Solar and Stellar Astrophysics · Physics 2019-12-04 T. Felipe , S. Esteban Pozuelo

Different methods for simulating the effects of spatial resolution on magnetic field maps are compared, including those commonly used for inter-instrument comparisons. The investigation first uses synthetic data, and the results are…

Solar and Stellar Astrophysics · Physics 2011-06-27 KD Leka , G. Barnes

With the advent of next generation high resolution telescopes, our understanding of how the magnetic field is organized in the internetwork (IN) photosphere is likely to advance.We aim to evaluate the extent to which we can retrieve…

Solar and Stellar Astrophysics · Physics 2021-10-04 R. J. Campbell , S. Shelyag , C. Quintero Noda , M. Mathioudakis , P. H. Keys , A. Reid

Spectropolarimetric observations used to infer the solar magnetic fields are obtained with a limited spatial resolution. The effects of this limited resolution on the inference of the open flux over the observed region have not been…

Solar and Stellar Astrophysics · Physics 2024-02-06 Ivan Milic , Rebecca Centeno , Xudong Sun , Matthias Rempel , Jaime de la Cruz Rodriguez

We study the effects of finite spectral resolution on the magnetic field values retrieved through the weak field approximation (WFA) from the cores of the Mg II h & k lines. The retrieval of the line-of-sight (LOS) component of the magnetic…

Solar and Stellar Astrophysics · Physics 2022-09-28 Rebecca Centeno , Matthias Rempel , Roberto Casini , Tanausu del Pino Aleman

Spectropolarimetric inversions are routinely used in the field of Solar Physics for the extraction of physical information from observations. The application to two-dimensional fields of view often requires the use of supercomputers with…

Solar and Stellar Astrophysics · Physics 2019-06-26 A. Asensio Ramos , C. Diaz Baso

We analysed state-of-the-art observations of the solar atmosphere to investigate the dependence of the \ca brightness of several solar features on spectral bandwidth and spatial resolution of the data. Specifically, we study data obtained…

Solar and Stellar Astrophysics · Physics 2023-04-20 M. Murabito , I. Ermolli , T. Chatzistergos , S. Jafarzadeh , F. Giorgi , L. Rouppe van der Voort

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…

Solar and Stellar Astrophysics · Physics 2021-01-20 P. H. Keys , O. Steiner , G. Vigeesh

Given its unchallenged capabilities in terms of sensitivity and spatial resolution, the combination of imaging spectropolarimetry and numeric Stokes inversion represents the dominant technique currently used to remotely sense the physical…

Instrumentation and Methods for Astrophysics · Physics 2019-11-05 Francisco A. Iglesias , Alex Feller

The magnetic fields in the solar polar region are important to our understanding of the internal dynamo process, the global coronal structure, and the origin of the solar wind. The inference of polar fields based on spectropolarimetric…

Solar and Stellar Astrophysics · Physics 2026-03-16 Bryan Yamashiro , Xudong Sun , Ivan Milić , Carlos Quintero Noda , Adur Pastor Yabar , Rebecca Centeno , Jiayi Liu , Milan Gošić , Kai Yang

Interpreting spectropolarimetric observations of the solar atmosphere takes much longer than the acquiring the data. The most important reason for this is that the model fitting, or "inversion", used to infer physical quantities from the…

Solar and Stellar Astrophysics · Physics 2020-12-16 Ivan Milic , Ricardo Gafeira

Small scale processes are thought to be important for the dynamics of the solar atmosphere. While numerical resolution fundamentally limits their inclusion in MHD simulations, real observations at the same nominal resolution should still…

Solar and Stellar Astrophysics · Physics 2022-06-23 Thore E. Moe , Tiago M. D. Pereira , Mats Carlsson

Polarimetric Synthetic Aperture Radar (PolSAR) images are an important source of information. Speckle noise gives SAR images a granular appearance that makes interpretation and analysis hard tasks. A major issue is the assessment of…

Applications · Statistics 2019-05-01 M. G. Palacio , S. B. Ferrero , A. C. Frery

Inversion codes are numerical tools used for the inference of physical properties from the observations. Despite their success, the quality of current spectropolarimetric observations and those expected in the near future presents a…

Solar and Stellar Astrophysics · Physics 2015-05-27 A. Asensio Ramos , J. de la Cruz Rodriguez

The deduction from solar flare X-ray photon spectroscopic data of the energy dependent model-independent spectral index is considered as an inverse problem. Using the well developed regularization approach we analyze the energy dependency…

Astrophysics · Physics 2009-11-11 Eduard P. Kontar , Alexander L. MacKinnon

Solar spectropolarimetric inversion -- inferring atmospheric conditions from the Stokes vector -- is a key diagnostic tool for understanding solar magnetism, but traditional inversion methods are computationally expensive and sensitive to…

Solar and Stellar Astrophysics · Physics 2025-11-17 Ryan James Campbell , Mihalis Mathioudakis , Carlos Quintero Noda
‹ Prev 1 2 3 10 Next ›