天体物理学与磁场Astrophysical Magnetism

【机器翻译自】

Magnetic fields are ubiquitous in space and play a major role in some of the most important astrophysical phenomena.

磁场在空间中无处不在,并且在某些最重要的天体物理学现象中起着重要作用。

The magnetic field along the Galactic plane

The magnetic field along the Galactic plane. The image portrays the interaction between interstellar dust in the Milky Way and the structure of our Galaxy’s magnetic field. Credit: ESA-Planck Collaboration, by Marc-Antoine Miville-Deschenes.Unlike the familiar magnetic fields on Earth, magnetic fields in space are not the passive result of electric currents, but  are dynamically active, self-generating the currents needed to sustain them through inductive processes in the highly-conducting plasma that fills space.

沿着银河平面的磁场。 该图像描绘了银河系中的星际尘埃与银河系磁场之间的相互作用。 图片来源:ESA-Planck Collaboration,Marc-Antoine Miville-Deschenes,与地球上熟悉的磁场不同,太空中的磁场不是电流的被动结果,而是动态主动产生的,自我产生维持电流所需的电流 通过充满空间的高传导等离子体中的感应过程。

Without magnetic fields, stars would form in a very different way, there would be no stellar winds, no cosmic rays, no accretion disks or jets in active binary stars and  active galactic nuclei,  no pulsars and perhaps no neutron stars at all, as magnetic fields seem to be essential to the Type II supernova explosions that form them. Nearly all the complex phenomena on the surface of the Sun are driven by magnetic fields.

没有磁场,恒星将以完全不同的方式形成,不会有恒星风,宇宙射线,活动双星和活动银河原子核中没有积聚盘或射流,没有脉冲星,甚至根本不会有中子星。 场似乎对形成它们的II型超新星爆炸必不可少。 太阳表面上几乎所有的复杂现象都是由磁场驱动的。

Although we know all this, there remains a huge amount to find out about cosmic magnetic fields. We don’t know where the seed fields came from that generated the magnetic fields in the interstellar medium of spiral galaxies and the intergalactic gas in clusters of galaxies. Detailed field patterns are poorly known, especially so in our own Milky Way Galaxy, where our view from inside makes it hard to see the big picture. Even in the best-studied cases such as the Sun, the complexity of magnetic phenomena such as reconnection leaves many questions still to answer.

尽管我们都知道这一点,但仍然需要大量了解宇宙磁场。 我们不知道种子场来自何处,而种子场是在螺旋星系的星际介质和星系团中的星系间气体中产生磁场的。 详细的场模式知之甚少,尤其是在我们自己的银河系星系中,从内部观看时很难看到大图景。 即使在研究最好的情况下(例如太阳),磁现象(如重新连接)的复杂性也使许多问题仍有待回答。

For this reason ‘The origin and Evolution of Cosmic Magnetism’ is one of the Key Science projects for the Square Kilometre Array. Radio astronomy provides some of the most important tracers of cosmic magnetism, including the Faraday and Zeeman effects which are the best two ways to measure the strength of magnetic fields in interstellar and intergalactic space, and so research into cosmic magnetism drives many research projects at JBCA.  

因此,“宇宙磁场的起源与演化”是平方公里阵列的关键科学项目之一。 射电天文学提供了宇宙磁场的一些最重要的示踪剂,包括法拉第效应和塞曼效应,这是测量星际和银河系空间中磁场强度的最好的两种方法,因此对宇宙磁场的研究推动了JBCA的许多研究项目 。

Leave a Reply