Impact of magnetic complexity in solar and astrophysical plasmas: Dundee-Durham consortium

太阳和天体物理等离子体中磁性复杂性的影响：邓迪-达勒姆联盟

• 批准号: ST/S000267/1
• 负责人: David Pontin
• 金额: $ 44.11万
• 依托单位: University of Dundee
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FS000267%2F1
• 关键词: Impact; magnetic; complexity; solar; astrophysical

This project is a continuation of a successful collaboration between the researchers of the Universities of Dundee and Durham on the behaviour of complex magnetic fields in astrophysical plasmas. Magnetic fields are ubiquitous in astrophysics. Closest to home they are generated inside rotating stars and planets (like the Sun and Earth), but they permeate much of the intervening space - for example, the Earth sits within the magnetised solar wind. Further afield, magnetic fields are observed on scales as vast as that of whole galaxies and as small as that of neutron stars. Where we observe them closely with modern telescopes, such as in the Sun's atmosphere, we find that these magnetic fields are highly complex, having spatial structure down to the smallest observable scales and significant dynamical behaviour. Magnetic fields play a crucial role in determining the behaviour of many of these systems - however, the implications of their ubiquitous complexity remain largely unexplored and poorly understood.The most spectacular impacts of magnetic fields are often found in the tenuous plasma above the visible surface of stars. In the Sun's atmosphere, for example, the magnetic field is responsible for creating long-lived structures such as coronal loops, for heating the corona to its multi-million degree temperatures, and for explosive events such as solar flares and coronal mass ejections. These powerful explosions lead to major space weather events at Earth, creating the Northern and Southern lights but also having the potential for damaging economic impacts on engineered systems, ranging from satellites and communication systems to power grids and pipelines. Yet these solar magnetic explosions are pitifully weak by comparison with the huge bursts observed from distant magnetars; perhaps not surprising given that these have the strongest magnetic fields known in the Universe. The overarching aim of the consortium is to explore the causes of magnetic complexity, and to determine its possible large-scale consequences. Can we explain the latest generation of high-resolution observations? Can this small-scale complexity have a significant effect even when we cannot observe it directly? How does the dynamical behaviour of magnetic fields lead to solar eruptions or magnetar bursts?The various projects within the consortium will carry out theoretical and numerical modelling for a range of different setups, carefully chosen to model the essential features of astrophysical plasmas including coronal loops, solar flares, neutron stars, and the sources of coronal mass ejections and the solar wind. Importantly, the modelling will take input from the latest generation of telescopes - several of our solar models will be directly "data-driven", and observations will be used to validate output. Many of our model predictions will be tailored to upcoming new observations, including those from DKIST and Parker Solar Probe. As well as probing the fundamental physics of astrophysical plasmas, the insight gained from our simulations will have practical application in the space-weather forecasting community. It is becoming apparent that forecasting the occurrence and impact of space weather events cannot rely on static extrapolation models but requires a deep understanding of the dynamical behaviour, and potentially the fine structure, of the Sun's magnetic field.

该项目延续了邓迪大学和达勒姆大学研究人员在天体物理等离子体中复杂磁场的行为的成功合作。磁场在天体物理学中无处不在。最接近家中的它们是在旋转的恒星和行星（如太阳和地球）中产生的，但是它们渗透到了许多介入空间 - 例如，地球位于磁性太阳风中。在更远的地方，在与整个星系一样广泛的尺度上观察到磁场，并且与中子恒星一样小。在我们用现代望远镜（例如在太阳的大气中）亲密观察它们的地方，我们发现这些磁场是高度复杂的，具有空间结构至最小的可观察到的尺度和明显的动力学行为。磁场在确定许多系统的行为方面起着至关重要的作用 - 但是，它们无处不在的复杂性的含义在很大程度上尚未探索和理解不足。磁场的最壮观影响通常是在恒星上可见表面上方的尖度等离子体中发现的。例如，在太阳的大气中，磁场负责创建长寿结构，例如冠状环，以将电晕加热到其数百万度的温度，以及爆炸性的事件，例如太阳耀斑和冠状质量弹出。这些强大的爆炸导致地球上发生了重大的太空天气事件，创造了北部和南部的光线，同时也有可能破坏对工程系统的经济影响，从卫星和通信系统到电网和管道。然而，与遥远的磁铁观察到的巨大爆发相比，这些太阳磁爆炸可怜。考虑到这些磁场在宇宙中已知最强的磁场，也许不足为奇。财团的总体目的是探索磁复杂性的原因，并确定其可能的大规模后果。我们可以解释最新一代的高分辨率观察结果吗？即使我们无法直接观察，这种小规模的复杂性也能产生重大影响吗？磁场的动力学行为如何导致太阳喷发或磁铁爆发？财团内的各种项目将针对一系列不同的设置进行理论和数值建模，仔细选择，以模拟天体物理等离子体的基本特征，包括冠状循环，包括太阳能星星，中子星和冠状动脉质量和Solar and solar and solar and solar and solar and solar and solar and solar and solar and solar and solar和solar wind。重要的是，该建模将从最新一代的望远镜中获取输入 - 我们的几种太阳能模型将直接“数据驱动”，并且将使用观测来验证输出。我们的许多模型预测将针对即将进行的新观察（包括来自DKIST和Parker太阳能探针的观察结果）量身定制。除了探测天体物理等离子体的基本物理学外，我们从模拟中获得的洞察力还将在太空天气预测社区中实用。显而易见的是，预测太空天气事件的发生和影响不能依赖于静态外推模型，而需要深入了解太阳磁场的动态行为，并可能对太阳磁场的精细结构进行深入了解。

项目成果

Evolution, Structure, and Topology of Self-generated Turbulent Reconnection Layers

• DOI: 10.3847/1538-4357/ac8eb6
• 发表时间: 2022-09
• 期刊: The Astrophysical Journal
• 作者: Raheem Beg;A. Russell;G. Hornig

Evolution, structure and topology of self-generated turbulent reconnection layers

自生湍流重联层的演化、结构和拓扑

• DOI: 10.48550/arxiv.2209.04492
• 发表时间: 2022
• 作者: Beg R

Topological constraints in the reconnection of vortex braids

涡辫重联的拓扑约束

• DOI: 10.1063/5.0047033
• 发表时间: 2021
• 期刊: Physics of Fluids
• 影响因子: 4.6
• 作者: Candelaresi S

The Dynamic Structure of Coronal Hole Boundaries

• DOI: 10.3847/1538-4357/ac69ed
• 发表时间: 2022-05
• 期刊: The Astrophysical Journal
• 作者: V. Aslanyan;D. Pontin;R. Scott;A. Higginson;P. Wyper;S. Antiochos

On self and mutual winding helicity

关于自旋和互旋螺旋

• DOI: 10.1016/j.cnsns.2021.106015
• 发表时间: 2021
• 期刊: Communications in Nonlinear Science and Numerical Simulation
• 影响因子: 3.9
• 作者: Candelaresi S