Modelling the asymmetries of the Sun's radial $p$-mode line profiles
| Autor: | J. Philidet, Hans-Günter Ludwig, Kevin Belkacem, Reza Samadi, C. Barban |
|---|---|
| Přispěvatelé: | Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Zentrum für Astronomie der Universität Heidelberg (ZAH), Universität Heidelberg [Heidelberg], Galaxies, Etoiles, Physique, Instrumentation (GEPI), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) |
| Rok vydání: | 2020 |
| Předmět: |
010504 meteorology & atmospheric sciences
media_common.quotation_subject FOS: Physical sciences Context (language use) Astrophysics 01 natural sciences Asymmetry methods: numerical Quality (physics) 0103 physical sciences Sun: oscillations 010303 astronomy & astrophysics Solar and Stellar Astrophysics (astro-ph.SR) 0105 earth and related environmental sciences media_common Sun: helioseismology Physics [PHYS]Physics [physics] [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] Oscillation Computer Science::Information Retrieval turbulence Mode (statistics) Spectral density Astronomy and Astrophysics line: profiles Wave equation Computational physics Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science [SDU]Sciences of the Universe [physics] [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] Free parameter |
| Zdroj: | Astronomy and Astrophysics-A&A Astronomy and Astrophysics-A&A, EDP Sciences, 2020, 635, pp.A81. ⟨10.1051/0004-6361/201936847⟩ |
| ISSN: | 0004-6361 |
| DOI: | 10.48550/arxiv.2001.10271 |
| Popis: | In this paper, we aim to develop a predictive model for solar radial $p$-mode line profiles in the velocity spectrum. Unlike the approach favoured by prior studies, this model is not described by free parameters and we do not use fitting procedures to match the observations. Instead, we use an analytical turbulence model coupled with constraints extracted from a 3D hydrodynamic simulation of the solar atmosphere. We then compare the resulting asymmetries with their observationally derived counterpart. We find that stochastic excitation localised beneath the mode upper turning point generates negative asymmetry for $\nu < \nu_\text{max}$ and positive asymmetry for $\nu > \nu_\text{max}$. On the other hand, stochastic excitation localised above this limit generates negative asymmetry throughout the $p$-mode spectrum. As a result of the spatial extent of the source of excitation, both cases play a role in the total observed asymmetries. By taking this spatial extent into account and using a realistic description of the spectrum of turbulent kinetic energy, both a qualitative and quantitative agreement can be found with solar observations perfoemed by the GONG network. We also find that the impact of the correlation between acoustic noise and oscillation is negligible for mode asymmetry in the velocity spectrum. Comment: 26 pages (19 without appendices), 14 figures. Accepted for publication in A&A |
| Databáze: | OpenAIRE |
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