Hanasoge Shravan M, Hotta Hideyuki, Sreenivasan Katepalli R
Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, Mumbai, India.
Center for Space Science, New York University, Abu Dhabi, UAE.
Sci Adv. 2020 Jul 22;6(30):eaba9639. doi: 10.1126/sciadv.aba9639. eCollection 2020 Jul.
Convection in the Sun's outer envelope generates turbulence and drives differential rotation, meridional circulation, and the global magnetic cycle. We develop a greater understanding of these processes by contrasting observations with simulations of global convection. These comparisons also enhance our comprehension of the physics of distant Sun-like stars. Here, we infer toroidal flow power as a function of wave number, frequency, and depth in the solar interior through helioseismic analyses of space-based observations. The inferred flows grow with spatial wave number and temporal frequency and are confined to low latitudes, supporting the argument that rotation induces systematic differences between the poles and equator. In contrast, the simulations used here show the opposite trends-power diminishing with increasing wave number and frequency while flow amplitudes become weakest at low latitudes. These differences highlight gaps in our understanding of solar convection and point to challenges ahead.
太阳外层包层中的对流产生湍流，并驱动较差自转、子午环流和全球磁循环。通过将观测结果与全球对流模拟进行对比，我们对这些过程有了更深入的理解。这些比较也增进了我们对遥远类日恒星物理的理解。在这里，我们通过对天基观测进行日震学分析，推断出太阳内部环形流功率随波数、频率和深度的变化函数。推断出的流随空间波数和时间频率增加而增大，并且局限于低纬度地区，这支持了自转在两极和赤道之间引起系统差异的观点。相比之下，这里使用的模拟显示出相反的趋势——功率随波数和频率增加而减小，而流幅在低纬度地区最弱。这些差异凸显了我们在理解太阳对流方面的差距，并指出了未来的挑战。
