English
Related papers

Related papers: Low-temperature gas opacity - AESOPUS: a versatile…

200 papers

Using the code AUTOSTRUCTURE, extensive calculations of inner-shell atomic data have been made for the chemical elements He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Cr, Mn, Fe and Ni. The results are used to obtain up-dated opacities from…

In the framework of the present phase -- IPOPv2 -- of the international Opacity Project (OP), a new web service has been implemented based on the latest release of the OP opacities. The user may construct online opacity tables to be…

Solar and Stellar Astrophysics · Physics 2016-02-17 F. Delahaye , C-M. Zwolf , C. Zeippen , C. Mendoza

RAPOC (Rosseland and Planck Opacity Converter) is a Python 3 code that calculates Rosseland and Planck mean opacities (RPMs) from wavelength-dependent opacities for a given temperature, pressure, and wavelength range. In addition to being…

Instrumentation and Methods for Astrophysics · Physics 2022-12-06 Lorenzo V. Mugnai , Darius Modirrousta-Galian

Aims. The derivation of spectroscopic parameters for M dwarf stars is very important in the fields of stellar and exoplanet characterization. The goal of this work is the creation of an automatic computational tool, able to derive quickly…

Solar and Stellar Astrophysics · Physics 2020-04-08 A. Antoniadis-Karnavas , S. G. Sousa , E. Delgado-Mena , N. C. Santos , G. D. C. Teixeira , V. Neves

A publicly available database of opacities for molecules of astrophysical interest, ExoMolOP, has been compiled for over 80 species, based on the latest line list data from the ExoMol, HITEMP and MoLLIST databases. These data are generally…

In this article, a software package code named OPSIAL (Optical Plasma Spectral Calculation And Parameters Retrieval) for rigorously calculating optical plasma spectra and for automatically retrieving plasma parameters is presented. OPSIAL…

Computational Physics · Physics 2018-02-06 Xiaofeng Tan

Tools for the spectroscopic determination of fundamental stellar parameters should not only comprise customized solutions for one particular survey or instrument, but, in order to enable cross-survey comparability, they should also be…

Solar and Stellar Astrophysics · Physics 2018-11-21 Michael Hanke , Camilla Juul Hansen , Andreas Koch , Eva K. Grebel

In this paper, we developed a spectral emulator based on the Mapping Nearby Galaxies at Apache Point Observatory Stellar Library (MaStar) and a grouping optimization strategy to estimate effective temperature (T_eff), surface gravity (log…

Solar and Stellar Astrophysics · Physics 2024-11-14 Jun-chao Liang , A-Li Luo , Yin-Bi Li , Xiao-Xiao Ma , Shuo Li , Shu-Guo Ma , Hai-Ling Lu , Yun-Jin Zhang , Bing Du , Xiao Kong

The equation of state (EOS) for partially ionized carbon, oxygen, and carbon-oxygen mixtures at temperatures 3\times10^5 K <~ T <~ 3\times10^6 K is calculated over a wide range of densities, using the method of free energy minimization in…

Plasma Physics · Physics 2011-11-16 G. Massacrier , A. Y. Potekhin , G. Chabrier

An extended version of the R-matrix methodology is presented for calculation of radiative parameters for improved plasma opacities. Contrast and comparisons with existing methods primarily relying on the Distorted Wave (DW) approximation…

Solar and Stellar Astrophysics · Physics 2023-08-30 A. K. Pradhan , S. N. Nahar , W. Eissner

The computation of complex neutral/ionised chemical equilibrium compositions is invaluable to obtain scientific insights of, for example, the atmospheres of extrasolar planets and cool stars. We present FastChem 2, a new version of the…

Earth and Planetary Astrophysics · Physics 2022-09-28 Joachim W. Stock , Daniel Kitzmann , A. Beate C. Patzer

We present a new equation of state (EOS) for dense hydrogen/helium mixtures which covers a range of densities from $10^{-8}$ to $10^6$ g.cm$^{-3}$, pressures from $10^{-9}$ to $10^{13}$ GPa and temperatures from $10^{2}$ to $10^{8}$ K. The…

Solar and Stellar Astrophysics · Physics 2019-02-20 G. Chabrier , S. Mazevet , F. Soubiran

This study introduces a framework that employs Gaussian Processes (GPs) to develop high-fidelity equation of state (EOS) tables, essential for modeling material properties across varying temperatures and pressures. GPs offer a robust…

Materials Science · Physics 2026-04-14 Lin H. Yang , James A. Gaffney

Using density functional molecular dynamics simulations, we determine the equation of state for hydrogen-helium mixtures spanning density-temperature conditions typical of giant planet interiors, ~0.2-9 g/cc and 1000-80000 K for a typical…

Earth and Planetary Astrophysics · Physics 2015-06-15 B. Militzer , W. B. Hubbard

Unambiguously identifying molecules in spectra is of fundamental importance for a variety of scientific and industrial uses. Interpreting atmospheric spectra for the remote detection of volatile compounds requires information about the…

Chemical Physics · Physics 2019-11-12 Clara Sousa-Silva , Janusz J Petkowski , Sara Seager

Water is one of the key chemical elements in planetary structure modelling. Due to its complex phase diagram, equations of state cover often only parts of the pressure - temperature space needed in planetary modelling. We construct an…

Earth and Planetary Astrophysics · Physics 2020-11-11 Jonas Haldemann , Yann Alibert , Christoph Mordasini , Willy Benz

GEMS is an IRAM 30m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dark cloud TMC 1.…

The internal working of low-mass stars is of great significance to both the study of stellar structure and the history of the Milky Way. Asteroseismology has the power to directly sense the internal structure of stars and allows for the…

Computing and using opacities is a key part of modeling and interpreting data of exoplanetary atmospheres. Since the underlying spectroscopic line lists are constantly expanding and currently include up to ~ 10^10 - 10^11 transition lines,…

Analytical equation of state for pure alkali metals (lithium, sodium, potassium, rubidium and cesium) in equilibrium gas phase is proposed. This equation has a simple form, generalizes the equation of state for a perfect gas and is…

Materials Science · Physics 2021-11-23 Anatolii V. Mokshin , Diana A. Mirziyarova