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Related papers: CAFE-PakalMPI: a new model to study the solar chro…

200 papers

In this work, we present the development of the Tonalli code: a simplified multi-species (HI, HII, H-, and e) magnetohydrodynamics (MHD) model in Non-local Thermodynamic Equilibrium (NLTE) focused on solar chromospheric conditions. This new…

We present a new code designed to solve the equations of classical ideal magneto-hydrodynamics (MHD) in three dimensions, submitted to a constant gravitational field. The purpose of the code centers on the analysis of solar phenomena within…

Solar and Stellar Astrophysics · Physics 2015-10-22 J. J. Gonzalez-Aviles , A. Cruz-Osorio , F. D. Lora-Clavijo , F. S. Guzman

We introduce CAFE, a new independent code designed to solve the equations of Relativistic ideal Magnetohydrodynamics (RMHD) in 3D. We present the standard tests for a RMHD code and for the Relativistic Hydrodynamics (RHD) regime since we…

General Relativity and Quantum Cosmology · Physics 2015-09-23 F. D. Lora-Clavijo , A. Cruz-Osorio , F. S. Guzman

Understanding the dynamics of the solar chromosphere is crucial to understanding energy transport across the solar atmosphere. The chromosphere is optically thick at many wavelengths and described by non-local thermodynamic equilibrium…

Solar and Stellar Astrophysics · Physics 2019-01-30 Jeffrey W. Reep , Stephen J. Bradshaw , Nicholas A. Crump , Harry P. Warren

The structure of the solar chromosphere is believed to be governed by magnetic fields, even in quiet-Sun regions that have a relatively weak photospheric field. During the past decade inversion methods have emerged as powerful tools for…

Solar and Stellar Astrophysics · Physics 2015-06-05 Jaime de la Cruz Rodríguez , Hector Socas-Navarro , Mats Carlsson , Jorrit Leenaarts

We present new or improved methods for calculating NLTE, line-blanketed model atmospheres for hot stars with winds (spectral types A to O), with particular emphasis on a fast performance. These methods have been implemented into a previous,…

Astrophysics · Physics 2009-11-10 J. Puls , M. A. Urbaneja , R. Venero , T. Repolust , U. Springmann , A. Jokuthy , M. R. Mokiem

We use a numerical code called PAKALMPI to compute synthetic spectra of the solar emission in quiet conditions at millimeter, sub-millimeter and infrared wavelengths. PAKALMPI solves the radiative transfer equation, with Non Local…

Solar and Stellar Astrophysics · Physics 2011-07-21 Victor De la Luz , Alejandro Lara , Jean-Pierre Raulin

Modeling the variability of the solar spectral irradiance is a key factor for understanding the solar influence on the climate of the Earth. As a first step to calculating the solar spectral irradiance variations we reproduce the solar…

Astrophysics · Physics 2009-11-13 M. Haberreiter , W. Schmutz , I. Hubeny

Large-scale stellar surveys, such as SDSS-V, 4MOST, WEAVE, and PLATO, require accurate atmospheric models and synthetic spectra of stars for accurate analyses of fundamental stellar parameters and chemical abundances. The primary goal of…

Solar and Stellar Astrophysics · Physics 2024-07-15 Philipp Eitner , Maria Bergemann , Richard Hoppe , Åke Nordlund , Bertrand Plez , Jonas Klevas

Non-local Thermodynamic Equilibrium (NLTE) calculations of hot white dwarf (WD) model atmospheres are the cornerstone of modern flux calibrations for the Hubble Space Telescope (HST) and for the CALSPEC database. These theoretical spectral…

Solar and Stellar Astrophysics · Physics 2020-06-17 Ralph Bohlin , Ivan Hubeny , Thomas Rauch

A recent third-order, essentially non-oscillatory central scheme to advance the equations of single-fluid magnetohydrodynamics (MHD) in time has been implemented into a new numerical code. This code operates on a 3-D Cartesian,…

Solar and Stellar Astrophysics · Physics 2012-04-18 Jens Kleimann , Andreas Kopp , Horst Fichtner , Rainer Grauer

The study of our Sun holds significant importance in Space Weather research, encompassing a diverse range of phenomena characterized by distinct temporal and spatial scales. To address these complexities, we developed CAFE-AMR, an…

Instrumentation and Methods for Astrophysics · Physics 2023-08-22 Ricardo Ochoa-Armenta , Francisco S. Guzmán

Manganese (Mn) is a key Fe-group elements, commonly employed in stellar population and nucleosynthesis studies to explore the role of SN Ia. We have developed a new non-local thermodynamic equilibrium (NLTE) model of Mn, including new…

We investigate departures from LTE in the line formation of Fe for a number of well-studied late-type stars in different evolutionary stages. A new model of Fe atom was constructed from the most up-to-date theoretical and experimental…

Solar and Stellar Astrophysics · Physics 2015-06-05 Maria Bergemann , Karin Lind , Remo Collet , Zazralt Magic , Martin Asplund

Context. The solar irradiance is known to change on time scales of minutes to decades, and it is suspected that its substantial fluctua- tions are partially responsible for climate variations. Aims. We are developing a solar atmosphere code…

Solar and Stellar Astrophysics · Physics 2015-05-18 A. I. Shapiro , W. Schmutz , M. Schoell , M. Haberreiter , E. Rozanov

An initial theoretical attempt to explain the observed decrease of the polytropic/adiabatic index $\gamma$ in the solar corona has been accomplished. The chemical reactions of the ionization-recombination processes in local thermodynamic…

Solar and Stellar Astrophysics · Physics 2023-12-25 Albert M. Varonov , Todor M. Mishonov

X-rays/EUV radiation emitted from wind-embedded shocks in hot, massive stars can affect the ionization balance in their outer atmospheres, and can be the mechanism responsible for the production of highly ionized species. To allow for these…

Solar and Stellar Astrophysics · Physics 2016-05-18 Luiz P. Carneiro , J. Puls , J. O. Sundqvist , T. L. Hoffmann

The KAPPA package is designed for calculations of optically thin spectra for the non-Maxwellian \k{appa}-distributions. This paper presents extension of the database to allow calculations of the spectra for extreme values of \k{appa} < 2,…

Solar and Stellar Astrophysics · Physics 2023-10-10 Elena Dzifcakova , Jaroslav Dudik , Martina Pavelkova , Bozena Solarova , Alena Zemanova

Detailed numerical models of chromosphere and corona are required to understand the heating of the solar atmosphere. An accurate treatment of the solar chromosphere is complicated by the effects arising from Non Local Thermodynamic…

Solar and Stellar Astrophysics · Physics 2022-08-17 D. Przybylski , R. Cameron , S. K. Solanki , M. Rempel , J. Leenaarts , L. S. Anusha , V. Witzke , A. I. Shapiro

We present accurate methods of abundance determination based on the non-local thermodynamic equilibrium (NLTE) line formation for carbon, oxygen, calcium, titanium, and iron in the atmospheres of BAF-type stars. For C I-II, O I, Ca I-II,…

Solar and Stellar Astrophysics · Physics 2018-08-22 Tatyana Sitnova , Tatyana Ryabchikova , Sofya Alexeeva , Lyudmila Mashonkina
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