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Lectures & Talks

Keynote Lectures
Prof. Ue-Li Pen - Magnetic Helicity
Dr. Rainer Beck - Observing magnetic fields in spiral galaxies

Lecture Series
Prof. Bryan Gaensler - Opening the window to the magnetic universe with radio polarimetry
Radio polarisation is a uniquely powerful probe of magnetism throughout the Universe: it can provide three-dimensional information on both the strength and direction of the magnetic field, can be used to detect magnetisation in a vast range of objects, and is sensitive to magnetic fields at almost any redshift. In this series of lectures, I will provide an overview of this rapidly evolving field, covering the following topics:
◆The basic theory of radio polarisation
◆Detection of magnetic fields using radio polarisation
◆The Faraday rotation technique
◆Recent new insights on astrophysical magnetism
◆The next generation of radio polarisation surveys

Prof. Christoph Pfrommer - A pedagogical introduction to cosmic rays, magnetic fields and galaxy formation
More than one century after the discovery of cosmic rays and 50 years after the first observation of an ultra high-energy cosmic ray with an energy exceeding 1e20 eV is their origin still a mystery and represents a major problem in theoretical astrophysics. The challenge consists of understanding the astrophysical environment and process that is able to accelerate an elementary particle to a kinetic energy which is equal to that of a golf ball traveling at about 100 km/h. In addition, we observe magnetic fields to be ubiquitous in the universe and to range from small planetary scales to large cosmological scales. In this lecture, we will learn about astrophysical mechanisms to accelerate charged elementary particles to extreme energies so that they form the population of cosmic rays and discuss how these particles are transported in galaxies. In addition, I will explain how magnetic fields are generated and amplified and will discuss how they can influence the dynamics of astrophysical systems. Finally, I will show that our modern-day understanding of galaxy formation requires a knowledge of these non-thermal components and demonstrate that they could hold the key to the physics of feedback by star formation and active galactic nuclei, which appears to be critical in obtaining realistic disk galaxies and to slow down star formation to the small observed rates. The course is aimed at master and PhD students as well as young postdocs of physics and astrophysics and will show the simplicity of this apparently complex physics by demystifying the topic; as such, it will hopefully answer questions about these topics that you may have and previously did not dare to ask.

Prof. Tetsuya Hashimoto - Fast radio bursts
This lecture series will include an overview of recent observational research progress on fast radio bursts (FRBs). FRBs are mysterious millisecond pulses in radio, most of which originate from distant galaxies. Despite more than 50 theoretical models of FRB progenitors, their origin is still unknown. Therefore, revealing the origin of FRBs is becoming central in astronomy and astrophysics. After learning some basic knowledge of FRBs, I will summarize the current observational constraints on the FRB progenitors. FRBs are expected to be useful cosmic probes to investigate key science in astronomy. The lecture will overview how we can address key science using FRBs, including dark energy, dark matter, missing baryon problem, cosmic reionization, Hubble constant tension, testing general relativity etc. At the end of the lecture series, I will introduce a new FRB telescope plan in Taiwan: Bustling Universe Radio Survey Telescope in Taiwan (BURSTT). A physics background would help better understand the lecture but any students without a background in astronomy and astrophysics are all welcome.

Dr. Kate Pattle - Magnetic fields in star formation: from molecular clouds to protostellar discs
A four-lecture series, focussing on our current understanding of the role of magnetic fields in star formation and molecular cloud formation and evolution
Lecture 1: Magnetic fields in molecular clouds
Lecture 2: Magnetised filament and core formation and evolution
Lecture 3: Magnetic fields in protostellar discs, jets and outflows
Lecture 4: Magnetic fields in HII regions

Dr. Siyao Xu - MHD turbulence in interstellar media
Turbulence and magnetic fields are ubiquitous in interstellar media. Magnetohydrodynamic (MHD) turbulence exists on all length scales and connects microscopic physics to macroscopic astrophysical observations. I will introduce some recent advances in MHD turbulence and its applications to understanding the physical processes in interstellar media. The lecture series will cover basic MHD turbulence physics, ion-neutral collisional damping of MHD turbulence in a weakly ionized interstellar phase, cosmic ray propagation in turbulent magnetic fields, applications of turbulent dynamo and turbulent reconnection of magnetic fields to star formation. 

Highlight Science Talks
Prof. Shih-Ping Lai - Observations of Magnetic fields in Galactic Star-forming Regions
The mechanisms behind the process of star formation at various stages of evolution are not fully understood. One area of debate is the relative importance of magnetic fields and turbulence in molecular clouds in regulating the formation and evolution of stars, as well as the fate of these clouds. To gain a better understanding of the role of these factors, it is necessary to study the environments surrounding protostars. The James Clerk Maxwell Telescope B-Fields In Star-forming Region Observations survey (BISTRO) has conducted the largest survey to date of Galactic Star-forming regions. The results of this survey will be discussed in this presentation.

Prof. Anna Scaife - Machine Learning for Classification of Faraday Depth Spectra
Classifying complexity in Faraday depth data provides important information about differences in magnetic structure along the line of sight toward polarised radio sources. This is relevant both to the investigation of complex structures, where little is currently known about various complex populations, and to statistical studies that require large samples of Faraday simple sources to be identified. In this talk I will discuss the use of simulated-to-real (Sim2Real) transfer learning for training deep-learning models to classify Faraday complexity using the LOFAR LoTSS DR2 RM Grid catalogue as an example. I will also discuss how we can validate such methods by evaluating the degree of consensus among human labellers when they are asked to classify Faraday structure.

Prof. Hsiang-Yi Karen Yang - Effects of magnetic field on AGN feedback in galaxy clusters
Feedback from active galactic nuclei (AGN) is believed to be the most promising mechanism for suppressing cooling flows in cool-core (CC) clusters. While much insights have been gained via purely hydrodynamic simulations, the effects of magnetic field play important roles in the processes of AGN feedback and cannot be neglected. In this talk, I will highlight some of the aspects where the magnetic field critically influences AGN feedback, including making the transport mechanisms such as conduction and viscosity anisotropic, and helping to suppress the formation of long-standing cold disks near cluster centers.

Dr. Amit Seta - Magnetic fields in the turbulent, multiphase ISM
Magnetic fields are a dynamically important component of the ISM of star-forming galaxies. The ISM is turbulent due to several driving mechanisms (i.e., supernova explosions and gravitational instabilities), and this turbulence amplifies and maintains magnetic fields in the ISM via the turbulent dynamo (i.e., the process of converting turbulent kinetic energy to magnetic energy). Furthermore, the ISM is multiphase due to various heating and cooling processes. The properties of turbulence and, by extension,  magnetic fields differ with the ISM phase. The talk will discuss some of the theoretical, observational, and numerical aspects of magnetic fields and turbulent dynamo in the multiphase ISM.

Dr. Jennifer Yik-Ham Chan - Probing large-scale cosmic magnetism with confidence
A correct understanding of the information encoded into cosmic messengers that we receive is essential to optimise the scientific gains from experiments and meaningfully compare theory to observation. In this talk, I will present a solid theoretical foundation of polarised radiative transfer in an expanding and evolving Universe and discuss the associated methodology underpinning the studies of large-scale cosmic magnetism with radio telescopes, such as the Very Large Array (VLA), the Low-Frequency Array (LOFAR), and the Square Kilometre Array (SKA). First, I will provide an overview of the ingredients essential to connecting the theory of magneto-genesis with observations. Then I will present the cosmological polarised radiative transfer (CPRT) formulation and demonstrate how it can be used to reliably predict the polarised radio emissions associated with magnetic fields that co-evolve with cosmic structure formation and evolution. I will conclude by summarising the key findings from the CPRT studies and highlighting the exciting opportunities of theoretical and observation advances in magnetism.

Dr. Ellis R. Owen - Magnetic fields, cosmic rays and star-formation in evolving galaxy ecosystems
Magnetic fields and charged cosmic rays are inextricably intertwined within galaxies. Magnetic fields control the propagation and distribution of cosmic rays, while the actions of cosmic rays can amplify, distort and redistribute magnetic fields. Guided by magnetic fields, cosmic rays can also reshape the hydrodynamic components of galactic ecosystems. As they deposit energy and momentum, cosmic rays drive heating throughout the internal multiphase interstellar media of galaxies, and modify baryon flows between galaxies and their circum-galactic environment. In turn, this can affect the supply of gas to a galaxy and its thermodynamic conditions, impacting its ability to form stars. Cosmic rays thus play an instrumental role in shaping galaxy evolution over a wide range of scales. They have a sufficient energy budget to form a significant 'hidden agent' of feedback, and may be the key to developing more compete models of galaxy formation and evolution. In this talk, I will outline the role cosmic rays and magnetic fields can play as feedback agents from clump to circum-galactic scales. I will discuss the microphysical processes governing cosmic ray interactions and their feedback efficiency in galaxy ecosystems, and introduce some of the exciting possibilities that will soon allow us to more comprehensively map-out the multi-scale influence of these high-energy particles in galaxies.