Liverpool John Moores University ARI Consolidated Grant 2021-2024

We will carry out work at the forefront of astrophysics using both observations and theory. The ARI's mission is to be a world-leading research centre at the highest international level of excellence. Our research uses the most advanced facilities and data analysis techniques. The projects in this case are technically demanding and require PDRA and other support to aid the delivery of the science.

Building on ARI's world-leading expertise in star formation (SF), we will investigate the connection between SF and gas physics in the Milky Way by mapping the SF efficiency in 3-D and studying the connection between SF and the gas distribution in the Galaxy. A second project will look at SF processes in different environments, and particularly in the conditions prevailing in the early Universe, to assess the survival probabilities of planetary systems as a function of environment and cosmological epoch.
We will determine how massive stars appear just before they die, by incorporating realistic mass-loss rates into calculations of their late-stage evolution, and building winds into the model atmospheres used to study these final phases.

We will address a major unsolved problem, the formation mechanism of globular clusters, using the recent discovery of multiple stellar populations in these systems (driven largely from ARI) to give a new perspective on this question. Globular clusters will also be used in a separate study to shed light on the evolution of their host galaxies, using a unique combination of detailed cluster formation physics embedded in world-leading cosmological simulations.

Through a joint analysis of major surveys of Milky Way (MW) stars (APOGEE, Gaia-WEAVE) and cosmological numerical simulations (EAGLE), we will address the contribution of satellite galaxies and in situ SF to the mass to the MW halo, and hence shed new light on the question of whether the MW is a typical galaxy.

Two of the proposed projects address cosmological questions. The first is a study of the long-lasting problem of the cosmological lithium abundance, which will be tackled through spectroscopic analysis of a large sample of metal-poor lower red giant branch stars. The second will look at the impact of massive neutrinos on cosmological structure formation, using a novel and highly efficient method based on non-linear cosmological perturbation theory.

Time-domain astrophysics has always been a core area of ARI research, underpinned by the world-leading 2-metre robotic Liverpool Telescope (LT). This application represents a broadening of this activity, encompassing compact object mergers and the full range of stellar explosions, from novae to GRBs. The one theoretical proposal in this area concerns modelling of nova super-remnants, motivated by the discovery of such a remnant in M31 by ARI researchers. This work has implications for nova population studies and pathways to SNIa events. We will compute the observable characteristics of supernova explosion models ofstars with different masses, degrees of stripping and explosion energies, and compare the outcomes with observations. We will also develop and exploit the first large, uniformly-selected, spectroscopically-complete sample of optical transients using the Zwicky Transient Facility. This will allow us to study the observational parameter space of all forms of stellar death and prepare for LSST.
A follow-up programme studying counterparts to gravitational wave events will provide a unique insight into the mergers of compact objects, combining observational studies with the development of new models for the characterisation of these events. These activities capitalise on ARI's expertise in this field and exploit our privileged access to the SN detection survey ZTF; LIGO-Virgo EM follow-up experiments, the Swift GRB satellite and observations on a range of leading astronomical facilities including the LT.

The ARI continues to run the long-established National Schools' Observatory (NSO) to foster the study of science, technology and maths in young people. This major educational resource, funded by LJMU, has supported over 10,000 primary & secondary schools to access the LT and has delivered more than 170,000 individual observations. The major form of impact in this case will be centred upon Projects 3, 5, 6, 10, and/or 13 (see Pathways to Impact and Section 4). These will benefit schools, amateur astronomers and the general public and will be particularly suitable for low Science Capital groups and hard-to-reach demographics (STFC Public Engagement Strategy 2016-2021). This will build on our considerable experience gained through the NSO and a suite of Distance Learning courses. It will provide opportunities for "active engagement" in the process of research, through online resources that will: (i) explore the ongoing research and (ii) allow anyone to work alongside researchers and make unique contributions.

In addition, there will be other more traditional forms of public engagement, through an ambitious programme of talks, workshops, presentations, panel discussions, artistic collaborations, Q&A sessions and articles. These will vary with respect to audience: schools (from primary upwards), amateur astronomy societies, lecture societies, WI, etc. We will also showcase the new research at events organised by the ARI (such as the annual Merseyside Astronomy Day) and others (e.g. Light Night Liverpool). The ARI has a track record of delivering provision off-the-beaten path. The STFC-funded Astronomy for Remote and Island Schools project has funded two ARI academics to tour schools in remote areas of the UK; they have visited 81 schools in total (5236 pupils and 1053 community members), and a final report on the project is being written to evaluate the project, with a February 2020 completion date. Obviously, an exposure to current research can stimulate inquiry and interest in any audience. However, perhaps a more important benefit is to use that stimulation to promote an appreciation of science as a whole. This is particularly important for engagement with schools where astronomy has a vital role to play in promoting science and other STEM subjects as potential careers. Finally, we will encourage and support all researchers, particularly research students and PDRAs, to share their research to a variety of audiences, with our experienced engagement team providing training and mentoring. The ARI also carries out single outreach events, benefitting often hard to reach audiences through working with non-science organisations to enhance their work while bringing our research to previous unengaged audiences. This sort of impact is difficult to predict, as it is usually opportunistic, but examples are: (i) arts organisations and artists (cinemas, art galleries, musicians, theatre and dance companies, sculptors, photographers, writers) and (ii) organisations promoting access to education (e.g. Ogden Trust).

The ARI's project combining infrared astronomical instrumentation expertise with drone technology is impacting the way conservation agencies around the world (e.g. WWF) conduct animal surveys. The thermal-drone enables safe, routine, efficient and cost-effective monitoring and management of animal populations over large and inhospitable areas, with a factor of up to 200x increase in survey efficiency over existing methods. This provides conservation agencies greatly improved data needed to quantify and mitigate biodiversity loss. The thermal drone system is being used routinely to help local fire-fighting teams to find/extinguish annual peat fires in Indonesia which are a major contributor to anthropogenic CO2 emissions. The orders of magnitude improvement in fire extinction efficiency the system offers over existing methods will hopefully lead to substantial reduction in CO2 emissions -- a leading cause of climate change.