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Related papers: Opacity calculations for stellar astrophysics

200 papers

We examine the role of opacities in stellar pulsation with reference to Cepheids and RR Lyraes, and examine the effect of augmented opacities on the theoretical pulsation light curves in key temperature ranges. The temperature ranges are…

Solar and Stellar Astrophysics · Physics 2018-06-11 S. M. Kanbur , M. Marconi , A. Bhardwaj , R. Kundu , H. P. Singh

Stellar models provide a vital basis for many aspects of astronomy and astrophysics. Recent advances in observational astronomy -- through asteroseismology, precision photometry, high-resolution spectroscopy, and large-scale surveys -- are…

Stars play a decisive role in our Universe, from its beginning throughout its complete evolution. For a thorough understanding of their properties, evolution, and physics of their outer envelopes, stellar spectra need to be analyzed by…

Solar and Stellar Astrophysics · Physics 2024-09-06 Joachim Puls , Artemio Herrero , Carlos Allende Prieto

In this lecture I discuss the bulk surface heterogeneity of rotating stars, namely gravity darkening. I especially detail the derivation of the omega-model of Espinosa Lara & Rieutord (2011), which gives the gravity darkening in early-type…

Solar and Stellar Astrophysics · Physics 2016-09-07 Michel Rieutord

We present the hybrid opacity code SCO-RCG which combines statistical approaches with fine-structure calculations. Radial integrals needed for the computation of detailed transition arrays are calculated by the code SCO (Super-configuration…

Atomic Physics · Physics 2019-04-30 Jean-Christophe Pain , Franck Gilleron , Quentin Porcherot , Thomas Blenski

Asteroseismology involves using the resonant frequencies of a star to infer details about its internal structure and evolutionary state. Oscillation frequencies are most useful when accompanied by accurate measurements of the more…

Astrophysics · Physics 2007-05-23 Timothy R. Bedding

The Sun is the most studied of all stars, and thus constitutes a benchmark for stellar models. However, our vision of the Sun is still incomplete, as illustrated by the current debate on its chemical composition. The problem reaches far…

Stellar seismology appears more and more as a powerful tool for a better determination of the fundamental properties of solar-type stars. However the particular case of Sun is still challenging. The helioseismic sound speed determination…

In this chapter I give an overall description of the structure and evolution of stars of different masses, and review the main ingredients included in state-of-the-art calculations aiming at reproducing observational features. I give…

Solar and Stellar Astrophysics · Physics 2017-12-27 Víctor Silva Aguirre

Despite recent major advances, the opacity remains a source of substantial uncertainty in the calculation of solar models, and hence of solar oscillation frequencies. Hence it is of substantial interest to investigate the sensitivity of…

Astrophysics · Physics 2009-09-25 S. C. Tripathy , J. Christensen-Dalsgaard

Stars play a key role in the evolution of the Universe, as sources of radiation, as dynamical engines, and as chemical factories. Outputs of stellar models are then central to various studies in astrophysics. Stellar physics links…

Solar and Stellar Astrophysics · Physics 2024-09-18 P. Eggenberger

Convection is the most important physical process that determines the structure of the envelopes of cool stars. It influences the surface radiation flux and the shape of observed spectral line profiles and is responsible for both generating…

Solar and Stellar Astrophysics · Physics 2009-12-03 F. Kupka

We present results of a {\bf comprehensive} asteroseismic modelling of the $\beta$ Cephei variable $\theta$ Ophiuchi. {\bf We call these studies {\it complex asteroseismology} because our goal is to reproduce both pulsational frequencies as…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. Daszynska-Daszkiewicz , P. Walczak

Stellar atmospheres separate the hot and dense stellar interiors from the emptiness of space. Radiation escapes from the outermost layers of a star, carrying direct physical information. Underneath the atmosphere, the very high opacity…

Solar and Stellar Astrophysics · Physics 2023-03-28 Carlos Allende Prieto

Laboratory (laser and Z-pinch) opacity measurements of well-characterized plasmas provide data to assist inertial confinement fusion, astrophysics and atomic-physics research. In order to test the atomic-physics codes devoted to the…

Plasma Physics · Physics 2020-02-19 Jean-Christophe Pain , Franck Gilleron

The study of neutron rich matter, present in neutron star, proto-neutron stars and core-collapse supernovae, can lead to further understanding of the behavior of nuclear matter in highly asymmetric nuclei. Heterogeneous structures are…

Nuclear Theory · Physics 2017-04-20 P. N. Alcain , C. O. Dorso

We present a comprehensive seismic study of the three pulsating stars of $\beta$ Cep/SPB type: $\nu$ Eridani, 12 Lacertae and $\gamma$ Pegasi. Models with the modified mean opacity profile are constructed in order to account for both the…

Solar and Stellar Astrophysics · Physics 2017-09-13 Przemysław Walczak , Jadwiga Daszyńska-Daszkiewicz , Alexey Pamyatnykh

Stellar evolution, a fundamental bedrock of modern astrophysics, is driven by the physical processes in stellar interiors. While we understand these processes in general terms, we lack some important ingredients. Seemingly small…

Astrophysics · Physics 2009-11-13 C. Aerts , J. Christensen-Dalsgaard , M. Cunha , D. W. Kurtz

Rotationally-split modes can provide valuable information about the internal rotation profile of stars. This has been used for years to infer the internal rotation behavior of the Sun. The present work discusses the potential additional…

Solar and Stellar Astrophysics · Physics 2015-05-18 J. C. Suárez , L. Andrade , M. J. Goupil , E. Janot-Pacheco

High-resolution observations by visible and near-infrared interferometers of both single stars and binaries have made significant contributions to the foundations that underpin many aspects of our knowledge of stellar structure and…