Lancaster University Astrophysics

The work proposed here tackles some of the most important open questions in astrophysics, broadly centred on understanding the formation and evolution of galaxies and the properties of the Universe itself. It is closely linked with the STFC Science Roadmap challenges pertaining to the roles and nature of dark matter and dark energy, the formation of the first stars and galaxies in the Universe, the still unsolved key question of how galaxies evolve and the development of stars and planets. In order to address such fundamental questions, we use complementary approaches involving observation and modelling of the most distant galaxies and relatively nearby systems of stars. We will shed light on the formation of the halo of our own Milky Way galaxy by measuring chemical abundances in globular clusters coupled with their motions as revealed by the Gaia mission. We will search nearby ultra-faint dwarf galaxies for evidence of the first generation of stars and the first supernova explosions to chemically enrich the environments of early galaxies. We will obtain a new sample of very distant galaxies using unique wide-area surveys, which provide the bright targets needed for detailed study of their physical properties. We will use the most distant Type Ia supernovae currently observable to improve our understanding of dark energy and the ultimate fate of the universe. Finally we will use modelling of stars that will potentially result in supernova explosions and, for the first time their planetary systems, to improve cosmological constraints by linking cosmology to stellar evolution and exo-planet research.

Our research involves making state-of-the-art observations using the world's most powerful and advanced telescopes such as the Hubble Space Telescope and facilities run by the European Southern Observatory including ALMA (the Atacama Large Millimeter Array) and the VLT (Very Large Telescope). At the same time the group is involved in the scientific planning for several new telescopes and instruments that will come online in the next 5-10 years and that will revolutionise research in astrophysics. These include the 4MOST spectrograph, the Large Synoptic Survey Telescope (LSST), the European Extremely Large Telescope (E-ELT) and in space the James Webb Space Telescope (JWST) and the European Space Agency's Euclid and FLARE missions.

The beneficiaries of this research are primarily academics interested in the important areas of STFC Science Challenges as described in the STFC Science Roadmap, particularly understanding how galaxies like our own Milky Way formed and evolved, improving the precision of SN Ia measurements to better understand the roles of dark matter and dark energy, understanding the distribution of dark matter, and processes in the early universe. The impact of this research will be disseminated in the form of open-access publications in peer-reviewed journals, and talks at national and international conferences.

The research also has important economic and societal impacts. Research in astronomy and astrophysics addresses some of the most fundamental questions about our origins and the Universe around us. The excitement it generates inspires young people to enter science and research. All members of the Astrophysics group give regular public lectures and will continue to use examples from their own research to enthuse public audiences. The group is also involved in the Physics department's schools outreach program, working with the departments Schools outreach Officer. The Department of Physics offers day-long "Cosmology and Astrophysics Masterclasses" and residential work experience and courses throughout the year. The new Observational Astrophysics group at Lancaster will augment and expand the provision of such Masterclasses. Similarly, Drs. Arridge and Koch have in the past contributed to closer collaborations between amateur astronomers and academic scientists, which we will continue in the future via talk series and interactions with, e.g., the British Astronomical Association.

Finally, the applicants on this proposal have an excellent record in media engagement. Prof. Hook is regularly approached by the media to comment on cosmology and the next generation of telescopes. Dr. Arridge has been interviewed on BBC Radio Lancashire and BBC Radio 5 Live, and for articles in BBC News Online. The results of Prof. Hook, and Drs. Sobral and Arridge are featured in the amateur astronomy media, such as Astronomy Now and Sky at Night magazine. Dr. Arridge is also an established writer for The Conversation, writing about planetary science and space exploration and reaching an audience of >80000 readers. His articles have been republished by Scientific American, The Washington Post, and Time.com.