Lancaster University Observational Astrophysics 2018-2021

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 and the still unsolved key question of how galaxies evolve. In order to address such fundamental questions, we use complementary approaches involving observation and modeling of the most distant and relatively nearby systems. We will shed light on the properties of nearby, faint dwarf galaxies by searching for traces of gas absorption in background quasar spectra. Looking further back in cosmic time, we will uncover the properties of thousands of "cosmic noon" galaxies, also along the lines-of-sight to distant QSOs, in order to explain the link between their star formation and the gas that fuels it. 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. Finally, we will use Type Ia supernovae to study the evolution of the universe itself, making fundamental tests of the constancy of dark energy in time, and preparing for tests of spatial variation.

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 10 years and that will revolutionise research in astrophysics. These include the 4-m Multi-Object Spectroscopic Telescope (4MOST), 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 mission.

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 some to sold out audiences such as Dr. Koch's lectures at "Haus der Astronomie" at the University of Heidelberg, and Dr. Sobral's ~10-15 public lectures reaching around 2000 people per year. The group 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 department's 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 is augmenting the provision of such Masterclasses.

The group also reaches out to non-converted audiences and seeks to widen public engagement with astronomy and astrophysics. Prior to moving to Lancaster, the newest member of the group, Dr. Stott, participated in Stargazing Oxford (2015-2016), a 6-monthly outreach event that attracts up to 1000 members of the public. 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. The work of Prof. Hook and Dr. Sobral are featured in the amateur astronomy media, such as Astronomy Now and Sky at Night magazine. Dr. Sobral has appeared in a major international 1-hour documentary produced by NHK (Japan) about the first stars and regarding his discovery of the CR7 galaxy.