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arXiv 1002.3489astro-ph.SR
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太阳辐射振荡的阻尼机制

Damping mechanisms for oscillations in solar prominences

I. Arregui, J. L. Ballester

摘要:

小振幅振荡是双折射/灯丝中常见的特征。这些振荡似乎是本地的性质,与日珥等离子体的精细结构,同时流动和逆流也存在。现有的观测证据表明,小振幅振荡,激发后,阻尼在短的空间和时间尺度上的一些尚未很好地确定的物理机制(S)。通常,这些振荡已被解释为线性磁流体动力学(MHD)波,本文回顾了最近提出的理论阻尼机制,以解释所观察到的衰减尺度。这些机制包括通过非绝热过程的热效应、质量流、非均匀介质中的共振阻尼和部分电离效应。通过将每个机制产生的空间和时间尺度与从观测中获得的尺度进行比较,评估每个机制的相关性。最后讨论了日珥地震学的最新理论成果在日珥地震学中的应用,旨在确定日珥等离子体中难以直接测量的物理参数。

英文摘要:

Small amplitude oscillations are a commonly observed feature in prominences/filaments. These oscillations appear to be of local nature, are associated to the fine structure of prominence plasmas, and simultaneous flows and counterflows are also present. The existing observational evidence reveals that small amplitude oscillations, after excited, are damped in short spatial and temporal scales by some as yet not well determined physical mechanism(s). Commonly, these oscillations have been interpreted in terms of linear magnetohydrodynamic (MHD) waves, and this paper reviews the theoretical damping mechanisms that have been recently put forward in order to explain the observed attenuation scales. These mechanisms include thermal effects, through non-adiabatic processes, mass flows, resonant damping in non-uniform media, and partial ionization effects. The relevance of each mechanism is assessed by comparing the spatial and time scales produced by each of them with those obtained from observations. Also, the application of the latest theoretical results to perform prominence seismology is discussed, aiming to determine physical parameters in prominence plasmas that are difficult to measure by direct means.

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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