Revealing the Pattern of Solar Alfvénic Waves - RiPSAW

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This research proposal aims to make advances in our understanding of the physics of our closest star, the Sun, and other solar-like stars. The Sun displays a number of fascinating and dynamic phenomena such as powerful solar flares and giant, planet-sized concentrations of magnetic fields (sunspots). It also provides a unique window that permits us to examine in detail how other stars behave. The Sun is made of a plasma (ionised gas) threaded by a strong magnetic field. Such magnetised plasmas are common throughout the universe (e.g. active galaxy nuclei, nebula, interstellar medium), hence the research will also aid advances across multiple research communities. Many stars possess their own weather systems, although these systems are extreme compared to those we experience on Earth. In our solar system, a hot, million degree wind blows off the Sun at colossal speeds reaching millions of miles per hour, washing over the planets. While we are under the protection of the Earth's magnetic field, that deflects the Sun's wind, other planetary bodies in the solar system have been exposed to its influence. For example, the Sun's wind is known to have stripped Mars of its atmosphere. Scientists are also interested in how these winds will influence the habitability of exoplanets around other Sun-like stars. These winds also contribute to how the stars evolve, with the Sun losing over 10 trillion tonnes of material each year via its winds. The objectives of the RiPSAW project are to examine a new mechanism related to the generation of the hot plasma and powerful winds, focusing on the role of magnetic waves. These magnetic (or Alfvén) waves are able to transfer energy through a star's atmosphere and are considered an important feature of any magnetic star. Exciting results from Dr Morton's recent observations of the Sun have found evidence that the magnetic waves are excited high in the atmosphere by sound waves leaking out from the inside of the Sun. This challenges our current knowledge of how energy is transported through a stars' atmosphere, hence the proposed work may transform the understanding of how these hot winds behave.To address these fundamental, yet unanswered, questions, RiPSAW makes use of advanced mathematical techniques and cutting-edge computer simulations to create models of the Sun based on magnetohydrodynamics. We combine this theoretical effort with the highest quality data of the Sun available from state-of-the-art solar instruments (e.g. NASA's Solar Dynamic Observatory); incorporating information from across the electromagnetic spectrum (e.g. visible, EUV) and analysing this with modern methods drawn from statistics and machine learning.