New Applicant Grant: Exploring the connection between solar flare energetic electrons observed at the Sun and in the heliosphere

The Solar Physics Group at Northumbria University has a long-term research programme to understand 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 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 our research also advances our understanding across multiple research communities.

Furthermore, we are also keen to determine how the Sun influences the near-Earth environment. The Sun is the powerhouse of our solar system and its daily variability can have profound consequences for Earth. Space Weather is the name given to the impact of events (e.g. solar flares, coronal mass ejections) from the Sun on our technologically- advanced society. This impact is both beautiful (e.g. Northern lights) and potentially extremely detrimental (e.g. damaging satellites, increasing radiation that is harmful to aircrew and astronauts). Thus, in order to understand and address the risks associated with Space Weather, we need to understand its origins and drivers.

Our work aims to address one of STFC's Science Challenges, namely "How do stars and planetary systems develop and how do they support the existence of life?", as well as key questions in the STFC Roadmap for Solar System Research, e.g. "What are the structures, dynamics and energetics of the Sun?" and "What are the fundamental processes at work in the Solar System?".

The project focuses on solar flares, a key component of space weather, and a laboratory for studying multiple aspects of high energy astrophysics. Solar flares produce radiation at all wavelengths, and unlike other astrophysical objects, there are abundant space and ground-based observatories viewing the Sun from radio to gamma-rays, using spatially resolved, high-resolution imaging and spectroscopy alongside Sun-as-a-star observations. Radiative diagnostics: X-ray bremsstrahlung, UV continuum, atomic line emission, and radio help us diagnose the properties of energetic particles at the Sun, and the extreme flaring plasma conditions. The Sun is the only star that permits in-situ detection of flare-accelerated electrons and ions (multi-messenger astronomy) at Earth (1 AU), and now within the Sun's corona (0.04 AU) with the successful launch of the Parker Solar Probe our "mission to touch the Sun", and the much anticipated ESA/NASA mission Solar Orbiter. The project is interested in understanding the energetics of solar flares and how high energy particles observed at the Sun and in the heliosphere are created in the Sun's atmosphere. This will be achieved by combining a multi-wavelength and multi-messenger observational study and by creating observationally-driven models in different plasma environments at the Sun and in the heliosphere.

The future impact for the New Applicant Grant closely follows from the Solar Physics Group at Northumbria University's latest Consolidated Grant (ST/T000384/1) research. It is multifaceted, covering Public Communication and Engagement, Knowledge Exchange, and Economic Impact; with clear pathways that will ensure we maximise the reach and significance.

The Solar Physics Group (SPG) has always been passionate about engaging and communicating science with the general public. The Applicant, as part of SPG, will work closely with dedicated experts in pedagogy and science communication (NUSTEM) to develop a clear and sustainable pathway to impact for our research. The SPG Public Communication and Engagement strategy is designed not only to inspire, but to increase the uptake of STEM disciplines, with a focus on growing science capital among women and other under-represented groups. This approach was honed by an STFC Public Engagement Small Award, which delivered the successful "Imagining the Sun" project (ST/N005562/1). We are continuing to deliver engagement through "Exploring Extreme Environments" which is funded by an STFC Nucleus Award (ST/S000070/1).

To ensure that this impact pathway has a lasting impact, we are also contributing to Continuing Professional Development. Project ST/S000070/1 will deliver CPD training sessions for teachers and provide training on the effective delivery of public engagement for PhD students, PDRAs and academics, which will permit high-quality communication of results to a wider audience. Moreover, we are leading the design and delivery of a series of Public Communication and Engagement workshops for academic researchers over the next 4 years as part of a pan-European Horizon2020 project (SOLARNET).

More generally, the Applicant will engage in a wider outreach programme with the public through mixed-methods: (i) public/school lectures which highlight the wonder and relevance of space science to a general audience; (ii) press releases and media interviews related to key science achievements; (iii) articles in public science magazines; (iv) science nuggets, and social media.

SPG is engaged with a university-wide multidisciplinary research theme called "Extreme Environments" which draws together research in understanding and harnessing physical environments that operate under extreme conditions, such as those found in the Earth's surface, oceans, atmosphere and in the solar system. As part of SPG, the Applicant will engage in Knowledge Exchange, interchanging skills/techniques gained during our research to other Theme members, which will be driven by the multidisciplinary nature of the Theme and will be achieved via scientific research meetings and active collaborations.

The SPG research programme will also increase the Applicant's knowledge and skills in the areas of mathematical modelling and High Performance Computing, and all researchers will gain further experience in problem solving and logical thinking. Transfer of these technical/professional skills - highly sought after in all employment sectors - will be achieved via our active collaborations, multidisciplinary projects, student projects, etc. Thus, our research programme will continually produce highly-skilled people for these in-demand areas.

Finally, the research has the potential for Economic Impact. Space weather features prominently on the UK National Risk Register of Civil Emergencies. Our research contributes to better understanding of the solar sources of space weather such as solar flares. This will have economic impact because adverse effects from solar flares have substantial financial implications, e.g. aviation disruption, communications blackouts, satellite damage.