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arXiv 2001.10271astro-ph.SR
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模拟太阳径向$p$模线轮廓的不对称性

Modelling the asymmetries of the Sun's radial $p$-mode line profiles

J. Philidet, K. Belkacem, R. Samadi, C. Barban, H. -G. Ludwig

备注：
26 pages (19 without appendices), 14 figures. Accepted for publication in A&A
发表信息：
A&A 635, A81 (2020)
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摘要：

在本文中，我们的目标是建立一个预测模型，太阳径向$p$模式线轮廓的速度谱。与以前的研究所青睐的方法不同，该模型不是由自由参数描述的，我们不使用拟合程序来匹配观测结果。相反，我们使用的分析湍流模型，再加上从太阳大气的三维流体动力学模拟提取的约束。然后，我们将由此产生的不对称性与观测得到的对应物进行比较。我们发现，随机激发下的模式下的上转折点产生负的不对称性为$ν< ν_\text{max}$和正的不对称性为$ν> ν_\text{max}$。另一方面，随机激发局部高于此限制产生负的不对称性在整个$p$模式频谱。由于激发源的空间范围，这两种情况下都在总的观察到的不对称性中发挥作用。通过考虑这种空间范围，并使用湍流动能谱的现实描述，可以发现与GONG网络执行的太阳观测的定性和定量的协议。我们还发现，噪声和振荡之间的相关性的影响是可以忽略不计的模式不对称的速度谱。

英文摘要：

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 $ν< ν_\text{max}$ and positive asymmetry for $ν> ν_\text{max}$. 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.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

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