Prospects and challenges of numerical modeling of the Sun at millimeter wavelengths
Prospects and challenges of numerical modeling of the Sun at millimeter wavelengths
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DOI：
10.3389/fspas.2022.967878
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发表时间：
2022-11
期刊：
影响因子：
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通讯作者：
S. Wedemeyer;G. Fleishman;J. de la Cruz Rodríguez;S. Gunár;J. M. da Silva Santos;P. Antolin;J. C. Guevara Gómez;M. Szydlarski;H. Eklund
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文献类型：
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作者：
S. Wedemeyer;G. Fleishman;J. de la Cruz Rodríguez;S. Gunár;J. M. da Silva Santos;P. Antolin;J. C. Guevara Gómez;M. Szydlarski;H. Eklund
阿塔卡马大毫米/亚毫米阵列(ALMA)提供了新的诊断可能性，补充了太阳研究的其他常用诊断方法。特别是，ALMA能够以前所未有的毫米波长空间分辨率作为色球气体的基本线性温度计，并在未来进行偏振测量，具有巨大的诊断潜力。因此，太阳ALMA观测有望大大有助于回答有关太阳大气外层的结构、动力学和能量平衡的长期问题。在这方面，目前和未来的ALMA数据对于限制和进一步发展太阳大气的数值模型也很重要，而数值模型又往往对解释观测结果至关重要。考虑到太阳高度间歇和动态的性质，涉及在空间和时间尺度上的大范围内发生的过多的过程，后者尤其重要。因此，对太阳进行现实的正演模拟需要考虑非平衡效应的随时间变化的三维辐射磁流体力学，并通常作为单独的步骤进行详细的辐射传输计算，从而产生可与观测值进行比较的合成可观测值。这种人造观测有时还考虑到仪器和视线效应，这除了有助于解释观测结果外，还为设计和优化ALMA的太阳观测模式提供了有益的工具。另一方面，ALMA数据与其他同步观测相结合，能够通过数据反演技术重建太阳大气结构。本文重点介绍了ALMA对太阳数值模拟的影响的主要方面，以及它们的潜力和挑战，以及精选的例子。
The Atacama Large Millimeter/submillimeter Array (ALMA) offers new diagnostic possibilities that complement other commonly used diagnostics for the study of the Sun. In particular, ALMA’s ability to serve as an essentially linear thermometer of the chromospheric gas at unprecedented spatial resolution at millimeter wavelengths and future polarization measurements has great diagnostic potential. Solar ALMA observations are therefore expected to contribute significantly to answering long-standing questions about the structure, dynamics, and energy balance of the outer layers of the solar atmosphere. In this regard, current and future ALMA data are also important for constraining and further developing numerical models of the solar atmosphere, which in turn are often vital for the interpretation of observations. The latter is particularly important given the Sun’s highly intermittent and dynamic nature that involves a plethora of processes occurring over extended ranges in spatial and temporal scales. Realistic forward modeling of the Sun therefore requires time-dependent three-dimensional radiation magnetohydrodynamics that account for non-equilibrium effects and, typically as a separate step, detailed radiative transfer calculations, resulting in synthetic observables that can be compared to observations. Such artificial observations sometimes also account for instrumental and seeing effects, which, in addition to aiding the interpretation of observations, provide instructive tools for designing and optimizing ALMA’s solar observing modes. In the other direction, ALMA data in combination with other simultaneous observations enable the reconstruction of the solar atmospheric structure via data inversion techniques. This article highlights central aspects of the impact of ALMA for numerical modeling of the Sun and their potential and challenges, together with selected examples.