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Related papers: Spectropolarimetric NLTE inversion code SNAPI

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We apply the HanleRT Tenerife Inversion Code to the spectro-polarimetric observations obtained by the Chromospheric LAyer SpectroPolarimeter. This suborbital space experiment measured the variation with wavelength of the four Stokes…

The Mg I b$_2$ line at 5173 \r{A} is primarily magnetically sensitive to heights between the mid photosphere and the low chromosphere, a region that has not been sufficiently explored in the solar atmosphere but is crucial for understanding…

Solar and Stellar Astrophysics · Physics 2025-03-18 A. L. Siu-Tapia , L. R. Bellot Rubio , D. Orozco Suárez , R. Gafeira

The new version of TLUSTY allows for the calculation of restricted NLTE in cool stars using pre-calculated opacity tables. We demonstrate that TLUSTY gives consistent results with MULTI, a well-tested code for NLTE in cool stars. We use…

Solar and Stellar Astrophysics · Physics 2020-05-20 Yeisson Osorio , Carlos Allende-Prieto , Ivan Hubeny , Szabolcs Meszaros , Matthew Shetrone

We present new observations of the center-to-limb variation of spectral lines in the quiet Sun. Our long-slit spectra are corrected for scattered light, which amounts to 4-8 % of the continuum intensity, by comparison with a Fourier…

Astrophysics · Physics 2009-11-10 C. Allende Prieto , M. Asplund , P. Fabiani Bendicho

The properties of magnetic fields forming an extended plage region in AR 10953 were investigated. Stokes spectra of the Fe I line pair at 6302 \AA recorded by the spectropolarimeter aboard the Hinode satellite were inverted using the SPINOR…

Solar and Stellar Astrophysics · Physics 2015-03-25 D. Buehler , A. Lagg , S. K. Solanki , M. van Noort

Most quantum machine learning (QML) pipelines still rely on static encodings such as angle and amplitude maps, and this limits their ability to handle temporal information. To address this limitation, this paper uses spike-based data…

Quantum Physics · Physics 2026-04-14 Nouhaila Innan , Rachmad Vidya Wicaksana Putra , Muhammad Shafique

It is generally accepted that the atmospheres of cool/lukewarm stars of spectral types A and later are described well by LTE model atmospheres, while the O-type stars require a detailed treatment of NLTE effects. Here model atmosphere…

Solar and Stellar Astrophysics · Physics 2015-06-03 Norbert Przybilla , Maria-Fernanda Nieva , Keith Butler

The Helioseismic and Magnetic Imager (HMI) has just started producing data that will help determine what the sources and mechanisms of variability in the Sun's interior are. The instrument measures the Doppler shift and the polarization of…

Solar and Stellar Astrophysics · Physics 2010-12-20 Rebecca Centeno , Steve Tomczyk , Juan Manuel Borrero , Sebastien Couvidat , Keiji Hayashi , Todd Hoeksema , Yang Liu , Jesper Schou

In this article, we review the interdisciplinary techniques (borrowed from physics, mathematics, statistics, machine-learning, etc.) and methodological framework that we have used to understand climate systems, which serve as examples of…

Data Analysis, Statistics and Probability · Physics 2024-05-29 Alka Yadav , Sourish Das , Anirban Chakraborti

We present observations of a solar plage in the millimeter-continuum with the ALMA and in the Ca 8542 and Na 5896 spectral lines with the Interferometric BIdimensional Spectrometer (IBIS). Our goal is to compare the measurement of local gas…

Solar and Stellar Astrophysics · Physics 2022-07-27 Ryan Hofmann , Kevin Reardon , Ivan Milic , Momchil Molnar , Yi Chai , Han Uitenbroek

Sunspots are prominent manifestations of the solar cycle and provide key constraints for understanding its operation. Also, knowing internal structure of sunspots allows us to gain insights on the energy transport in strong magnetic fields…

Solar and Stellar Astrophysics · Physics 2010-03-29 R. Wenzel , S. V. Berdyugina , D. M. Fluri , J. Arnaud , A. Sainz-Dalda

AIMS :The thermodynamic and magnetic field structure of the solar photosphere is analyzed by means of a novel 3-dimensional spectropolarimetric inversion and reconstruction technique. METHODS : On the basis of high-resolution,…

Astrophysics · Physics 2008-03-10 T. A. Carroll , M. Kopf

Magnetic fields are ubiquitous in active cool stars but they are in general complex and weak. Current Zeeman Doppler imaging (ZDI) studies of cool star magnetic fields chiefly employ circular polarization observations because linear…

Solar and Stellar Astrophysics · Physics 2015-06-03 Lisa Rosén , Oleg Kochukhov , Gregg A. Wade

A big challenge in solar and stellar physics in the coming years will be to decipher the magnetism of the solar outer atmosphere (chromosphere and corona) along with its dynamic coupling with the magnetic fields of the underlying…

Astrophysics · Physics 2009-11-13 A. Asensio Ramos , J. Trujillo Bueno , E. Landi Degl'Innocenti

We construct a comprehensive model atom for TiI-II using more than 3600 measured and predicted energy levels of TiI and 1800 energy levels of TiII, and quantum mechanical photoionisation cross-sections. Non-local thermodynamical equilibrium…

Solar and Stellar Astrophysics · Physics 2016-07-27 T. M. Sitnova , L. I. Mashonkina , T. A. Ryabchikova

Magnetic fields are one of the most important drivers of the highly dynamic processes that occur in the lower solar atmosphere. They span a broad range of sizes, from large- and intermediate-scale structures such as sunspots, pores and…

Solar and Stellar Astrophysics · Physics 2015-03-13 Stefan Thonhofer , Luis R. Bellot Rubio , Dominik Utz , Arnold Hanslmeier , Jan Jurčák

We present tonalli, a spectroscopic analysis python code that efficiently predicts effective temperature, stellar surface gravity, metallicity, $\alpha$-element abundance, and rotational and radial velocities for stars with effective…

Instrumentation and Methods for Astrophysics · Physics 2024-11-26 Lucía Adame , Carlos Román-Zúñiga , Jesús Hernández , Ricardo López-Valdivia , Edilberto Sánchez

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

The study of planetary atmospheres is crucial for understanding the origin, evolution, and processes that shape celestial bodies like planets, moons and comets. The interpretation of planetary spectra requires a detailed understanding of…

Earth and Planetary Astrophysics · Physics 2023-10-31 Miriam Rengel , Jakob Adamczewski

In a previous paper, we argued that the inversion of Stokes profiles applied to spectropolarimetric observations of the solar internetwork yield unrealistically large values of the inclination of the magnetic field vector ($\gamma$). This…

Solar and Stellar Astrophysics · Physics 2015-06-11 J. M. Borrero , P. Kobel
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