日本超级计算机:富岳成功再现:太阳的特殊自转,

日本超级计算机:富岳成功再现:太阳的特殊自转,

-对阐明黑点数量波动的期望-

2021/9/14

千叶大学:

千叶大学等研究团队在世界上首次取得成功。

传统的超级计算机不可能:

使用传统的超级计算机模拟,不可能重现太阳的特殊自转。

用最新的超级计算机Fugaku转载:

我们成功地用世界上最高性能的超级计算机“Fugaku”再现了太阳的特殊旋转。

太阳物理学中最大的谜团:

对太阳特殊自转周期的阐明被认为是太阳物理学中最大的谜团。

据说这将导致阐明太阳黑点数量以大约11年为一个周期波动的现象。

太阳的自转周期比较特殊:

与在所有纬度以相同速度自转的地球不同,太阳的自转周期是特殊的。

在北极和南极附近大约需要30天,

赤道附近约25天

长期以来,人们通过观察就知道了这一点。

似乎是“占据半径外约30%的热对流层的作用”造成的。

我不知道细节。

科研团队模拟:

将整个热对流层分成54亿个点,

每个的密度、温度、压力等

通过精确应用进行模拟。

仿真结果:

结果,我们能够重现太阳的自转,这与观察到的数据几乎相同。

在过去的超级计算机中,热对流层只能分为大约 2 亿个点。

这一次,观测点变得更加精细,并且产生的磁场被准确地再现。

太阳自转与太阳黑子形成的关系:

据说太阳的自转与太阳黑子的形成密切相关。

太阳黑子每 11 年增加和减少一次。

当有很多时,太阳耀斑爆炸

发出强烈的电磁波,

损害人造卫星和电力线,

千叶大学副教授 Hideyuki Hotta:

我想通过模拟加深我对太阳自转的理解。

这将导致阐明太阳黑子周期性增加和减少的奥秘。

https://www.sankeibiz.jp/business/news/210914/cpc2109140711004-n1.htm

Solar differential rotation reproduced with high-resolution simulation

H. Hotta Department of Physics, Graduate School of Science, Chiba University, Chiba, Japan

The Sun rotates differentially with a fast equator and slow pole1.

Convection in the solar interior is thought to maintain the differential rotation.

However, although many numerical simulations

have been conducted to reproduce the solar differential rotation2,3,4,5,6,7, previous high-resolution calculations with solar parameters fall into the antisolar (fast-pole) differential rotation regime.

Consequently,
we still do not know the true reason why the Sun has a fast-rotating equator.

While
the construction of the fast equator requires a strong rotational influence on the convection,

the previous calculations
have not been able to achieve the situation without any manipulations.

The problem is called the convective conundrum8.

The convection and the differential rotation in numerical simulations were different from the observations.

Here, we show that
a high-resolution calculation succeeds in reproducing the solar-like differential rotation.

Our calculations indicate that
the strong magnetic field generated by a small-scale dynamo has a significant impact on thermal convection.

The successful reproduction of the differential rotation, convection and magnetic field

achieved in our calculation is an essential step to understanding the cause of the most basic nature of solar activity, specifically, the 11 yr cycle of sunspot activity.

Nature Astronomy

https://www.nature.com/articles/s41550-021-01459-0