Astrophysics at Oxford 2019-2022
Lead Research Organisation:
UNIVERSITY OF OXFORD
Department Name: Oxford Physics
Abstract
Astrophysical research at Oxford University is carried out by investigators with universal interests, spanning scales from planetary to cosmic. We are actively engaged with many of the most exciting questions of modern physics.
On the scale of planetary phenomena, we seek to find new worlds and to understand how their atmospheres behave under extreme conditions. With knowledge of a planet's atmosphere, we may be able to learn something of its composition, and how it has evolved. Planetary researchers are interested in how other solar systems form and change with time, and why they seem to be so different from our own.
The study of black holes is one of the most exciting areas of astrophysics. We investigate the turbulent gas processes by which black holes grow as they accrete surrounding material, and calculate what one might observe when massive black holes in the centres of galaxies rip apart stars by tidal forces and devour the debris. Gas accretion can produce spectacular fireworks in a quasar or active galaxy, or barely a blip in the case of our own Milky Way Galaxy. Oxford researchers measure the radiation from molecules in distant galaxies to reveal the properties of the central black holes and their surroundings. We pursue studies at the cutting edge of black hole formation, tracking the radio waves emerging from the debris of neutron stars that have collided and coalesced into a black hole, and using this to understand the physics of this remarkable cosmic catastrophe.
On scales associated with our own Milky Way Galaxy, we study the motion of individual stars in great detail, using the results to understand how our Galaxy formed and maintains its structure, and how a great halo of invisible dark matter, which keeps the Galaxy bound, betrays its presence through the motions of the stars. We exploit observations of the galactic cluster environment, vast volumes filled with rarified magnetised gas heated to X-ray temperatures, to constrain the fundamental properties of matter suggested by string theory.
The evolution of galaxies throughout the Universe is influenced by their environment, which is in turn impacted by galactic feedback. To unravel the details of this galactic coupling through cosmic time is an enormous task. It requires the analysis of vast amounts of observational data. We maintain a large, active group of researchers pursuing this grand problem in all of its scope, from the highest redshifts at which galaxies form up to present cosmic times. Questions pertaining to the rate of star formation throughout cosmic time, to how galactic morphology may itself evolve, to whether the presence of neighbours causes galaxies' spin rotations to align, to how central black holes develop, are all being investigated at Oxford. This involves the use of current facilities as well as planning the design and implementation of key instruments to be associated with major international collaborations.
The largest scales of all are associated with the CMB, the cosmic microwave background. The exquisitely difficult but essential process of excising the foreground contamination caused by our own Galaxy is led by the Oxford team designing and building the C-BASS instrument. This is an example of how our researchers are developing techniques to coax profound secrets of the Universe from very sensitive data. What were the initial tiny fluctuations that gave rise to galaxies and their larger scale clusters? What constraints can be placed on the masses of elementary particles and deviations from classical general relativity? By combining information from CMB instruments like Planck with other data sets related to galaxy clustering, powerful new tools are being developed.
On the scale of planetary phenomena, we seek to find new worlds and to understand how their atmospheres behave under extreme conditions. With knowledge of a planet's atmosphere, we may be able to learn something of its composition, and how it has evolved. Planetary researchers are interested in how other solar systems form and change with time, and why they seem to be so different from our own.
The study of black holes is one of the most exciting areas of astrophysics. We investigate the turbulent gas processes by which black holes grow as they accrete surrounding material, and calculate what one might observe when massive black holes in the centres of galaxies rip apart stars by tidal forces and devour the debris. Gas accretion can produce spectacular fireworks in a quasar or active galaxy, or barely a blip in the case of our own Milky Way Galaxy. Oxford researchers measure the radiation from molecules in distant galaxies to reveal the properties of the central black holes and their surroundings. We pursue studies at the cutting edge of black hole formation, tracking the radio waves emerging from the debris of neutron stars that have collided and coalesced into a black hole, and using this to understand the physics of this remarkable cosmic catastrophe.
On scales associated with our own Milky Way Galaxy, we study the motion of individual stars in great detail, using the results to understand how our Galaxy formed and maintains its structure, and how a great halo of invisible dark matter, which keeps the Galaxy bound, betrays its presence through the motions of the stars. We exploit observations of the galactic cluster environment, vast volumes filled with rarified magnetised gas heated to X-ray temperatures, to constrain the fundamental properties of matter suggested by string theory.
The evolution of galaxies throughout the Universe is influenced by their environment, which is in turn impacted by galactic feedback. To unravel the details of this galactic coupling through cosmic time is an enormous task. It requires the analysis of vast amounts of observational data. We maintain a large, active group of researchers pursuing this grand problem in all of its scope, from the highest redshifts at which galaxies form up to present cosmic times. Questions pertaining to the rate of star formation throughout cosmic time, to how galactic morphology may itself evolve, to whether the presence of neighbours causes galaxies' spin rotations to align, to how central black holes develop, are all being investigated at Oxford. This involves the use of current facilities as well as planning the design and implementation of key instruments to be associated with major international collaborations.
The largest scales of all are associated with the CMB, the cosmic microwave background. The exquisitely difficult but essential process of excising the foreground contamination caused by our own Galaxy is led by the Oxford team designing and building the C-BASS instrument. This is an example of how our researchers are developing techniques to coax profound secrets of the Universe from very sensitive data. What were the initial tiny fluctuations that gave rise to galaxies and their larger scale clusters? What constraints can be placed on the masses of elementary particles and deviations from classical general relativity? By combining information from CMB instruments like Planck with other data sets related to galaxy clustering, powerful new tools are being developed.
Planned Impact
Astronomy inspires and fascinates the specialist and non-specialist alike. Many Department members, representing a wide variety of interests, give public talks at all levels, including primary schools, high schools, policy makers, and industry. These activities are not merely confined to the UK, they extend into continental Europe and developing countries. We also hold hugely popular Stargazing Events for the public throughout the year, and engage the public more deeply in our activities with programmes like the citizen science projects Zooniverse, MoonZoo and Planet Hunters. Enabling schools in developing countries to carry out astronomy research via the Global Jet Watch Project is a particularly far-reaching activity.
In addition to our educational efforts, our research findings make significant contributions in areas such as turbulence (both when it occurs and when, despite expectations, it does not), weak signal detection, and heating and energy transfer in plasmas. These contributions are all important in making progress towards the solutions of societal problems. The challenge for us as astrophysicists is to understand the physical phenomena that are present under the extreme conditions found throughout the Universe, conditions that cannot be replicated in the laboratory. In meeting this challenge, we are able to understand and explore the laws of physics in environments that would not be remotely plausible or affordable here on Earth.
A case in point is that of plasma physics, in which progress in fusion is so crucial to the enduring supply of safe energy for the inhabitants of this planet. The sorts of problems frequently encountered in the development of fusion devices (e.g. anomalous energy transport and instabilities) have precise analogues in the study of astrophysical plasmas. We have close intellectual ties and many exchange visits with UKAEA Culham in order to expedite this knowledge exchange.
Climate change too, is of profound importance for the future. It can be difficult for the non-specialist to understand the important influences and consequences and is hindered by confused representations in the popular press. Astronomy, however, is non-partisan, and so the understanding gained from planets that are not our own makes it easier to comprehend, and bring a cleaner perspective to, the problems we have to grapple with on our home planet. In this way, case studies of exoplanets have the potential to make science that is ultimately important to life on Earth more accessible to the general public.
The state-of-the-art instrumentation with which we detect the most sensitive primordial signals from the early Universe drives significant advancements in industrial development. The research and development in, for example, our C-BASS project is feeding back into next-generation instrumentation such as the SKA radio telescope and industry itself. With further enhancements to our instrumentation programmes will come stimulation to industry in areas such as communications, microwave receivers, optics, interferometry, digital signal processing and remote sensing.
The extraction of minute signals from overwhelming backgrounds now involves advanced computation techniques. Our computational work thus has many positive consequences in the field of "Big Data", software development, as well as complex computation on GPUs - the graphics cards within even modest desktop computers that have been developed by the games industry - that we are exploiting for data management and computation.
In addition to our educational efforts, our research findings make significant contributions in areas such as turbulence (both when it occurs and when, despite expectations, it does not), weak signal detection, and heating and energy transfer in plasmas. These contributions are all important in making progress towards the solutions of societal problems. The challenge for us as astrophysicists is to understand the physical phenomena that are present under the extreme conditions found throughout the Universe, conditions that cannot be replicated in the laboratory. In meeting this challenge, we are able to understand and explore the laws of physics in environments that would not be remotely plausible or affordable here on Earth.
A case in point is that of plasma physics, in which progress in fusion is so crucial to the enduring supply of safe energy for the inhabitants of this planet. The sorts of problems frequently encountered in the development of fusion devices (e.g. anomalous energy transport and instabilities) have precise analogues in the study of astrophysical plasmas. We have close intellectual ties and many exchange visits with UKAEA Culham in order to expedite this knowledge exchange.
Climate change too, is of profound importance for the future. It can be difficult for the non-specialist to understand the important influences and consequences and is hindered by confused representations in the popular press. Astronomy, however, is non-partisan, and so the understanding gained from planets that are not our own makes it easier to comprehend, and bring a cleaner perspective to, the problems we have to grapple with on our home planet. In this way, case studies of exoplanets have the potential to make science that is ultimately important to life on Earth more accessible to the general public.
The state-of-the-art instrumentation with which we detect the most sensitive primordial signals from the early Universe drives significant advancements in industrial development. The research and development in, for example, our C-BASS project is feeding back into next-generation instrumentation such as the SKA radio telescope and industry itself. With further enhancements to our instrumentation programmes will come stimulation to industry in areas such as communications, microwave receivers, optics, interferometry, digital signal processing and remote sensing.
The extraction of minute signals from overwhelming backgrounds now involves advanced computation techniques. Our computational work thus has many positive consequences in the field of "Big Data", software development, as well as complex computation on GPUs - the graphics cards within even modest desktop computers that have been developed by the games industry - that we are exploiting for data management and computation.
Publications
Hinkley S
(2023)
Direct discovery of the inner exoplanet in the HD 206893 system Evidence for deuterium burning in a planetary-mass companion
in Astronomy & Astrophysics
Hogan L
(2021)
Integral field spectroscopy of luminous infrared main-sequence galaxies at cosmic noon
in Monthly Notices of the Royal Astronomical Society
Hogan L
(2022)
Unveiling the main sequence to starburst transition region with a sample of intermediate redshift luminous infrared galaxies
in Monthly Notices of the Royal Astronomical Society
Holwerda B
(2019)
The Frequency of Dust Lanes in Edge-on Spiral Galaxies Identified by Galaxy Zoo in KiDS Imaging of GAMA Targets
in The Astronomical Journal
Hosking D
(2020)
Elasticity of tangled magnetic fields
Hosking D
(2020)
Elasticity of tangled magnetic fields
in Journal of Plasma Physics
Ingram A
(2021)
Erratum: A self-lensing binary massive black hole interpretation of quasi-periodic eruptions
in Monthly Notices of the Royal Astronomical Society
Ingram A
(2021)
A self-lensing binary massive black hole interpretation of quasi-periodic eruptions
in Monthly Notices of the Royal Astronomical Society
Irwin P
(2020)
2.5D retrieval of atmospheric properties from exoplanet phase curves: application to WASP-43b observations
in Monthly Notices of the Royal Astronomical Society
Ivezic Ž
(2019)
LSST: From Science Drivers to Reference Design and Anticipated Data Products
in The Astrophysical Journal
Jarvis M
(2020)
K-CLASH: Strangulation and ram pressure stripping in galaxy cluster members at 0.3 < z < 0.6
in Monthly Notices of the Royal Astronomical Society
Jarvis M
(2024)
The discovery of a z = 0.7092 OH megamaser with the MIGHTEE survey
in Monthly Notices of the Royal Astronomical Society
Jarvis M
(2023)
The discovery of a z=0.7092 OH megamaser with the MIGHTEE survey
Jew L
(2019)
The C-Band All-Sky Survey (C-BASS): Simulated parametric fitting in single pixels in total intensity and polarization.
in Monthly notices of the Royal Astronomical Society
Jofré P
(2020)
Ages and kinematics of chemically selected, accreted Milky Way halo stars
in Monthly Notices of the Royal Astronomical Society
Joudaki S.
(2019)
KiDS+VIKING-450 and DES-Y1 combined: Cosmology with cosmic shear
in arXiv e-prints
Kawazura Y
(2022)
Energy partition between Alfvénic and compressive fluctuations in magnetorotational turbulence with near-azimuthal mean magnetic field
in Journal of Plasma Physics
Kawazura Y
(2020)
Ion versus Electron Heating in Compressively Driven Astrophysical Gyrokinetic Turbulence
in Physical Review X
Kaye L
(2022)
Transit timings variations in the three-planet system: TOI-270
in Monthly Notices of the Royal Astronomical Society
Keel W
(2018)
AGN photoionization of gas in companion galaxies as a probe of AGN radiation in time and direction
in Monthly Notices of the Royal Astronomical Society
Kerkeni B
(2022)
Probing computational methodologies in predicting mid-infrared spectra for large polycyclic aromatic hydrocarbons
in Monthly Notices of the Royal Astronomical Society
Klein B
(2022)
One year of AU Mic with HARPS - II. Stellar activity and star-planet interaction
in Monthly Notices of the Royal Astronomical Society
Kodwani D
(2019)
The effect on cosmological parameter estimation of a parameter dependent covariance matrix
in The Open Journal of Astrophysics
Kondapally R
(2021)
The LOFAR Two-meter Sky Survey: Deep Fields Data Release 1 III. Host-galaxy identifications and value added catalogues
in Astronomy & Astrophysics
Koukoufilippas N
(2020)
Tomographic measurement of the intergalactic gas pressure through galaxy-tSZ cross-correlations
in Monthly Notices of the Royal Astronomical Society
Koushan S
(2021)
GAMA/DEVILS: constraining the cosmic star formation history from improved measurements of the 0.3-2.2 µ m extragalactic background light
in Monthly Notices of the Royal Astronomical Society
Krajnovic D
(2020)
Formation channels of slowly rotating early-type galaxies
in Astronomy & Astrophysics
Kraljic K
(2022)
Forecasts for WEAVE-QSO: 3D clustering and connectivity of critical points with Lyman- a tomography
in Monthly Notices of the Royal Astronomical Society
Kruk S
(2019)
Revealing the cosmic evolution of boxy/peanut-shaped bulges from HST COSMOS and SDSS
in Monthly Notices of the Royal Astronomical Society
Lam K
(2020)
It Takes Two Planets in Resonance to Tango around K2-146
in The Astronomical Journal
Lamperti I
(2022)
Physics of ULIRGs with MUSE and ALMA: The PUMA project IV. No tight relation between cold molecular outflow rates and AGN luminosities
in Astronomy & Astrophysics
Lau J
(2021)
Probabilistic distribution functions
in Monthly Notices of the Royal Astronomical Society
Lau J
(2019)
Relaxation of spherical stellar systems
in Monthly Notices of the Royal Astronomical Society
Lau J
(2021)
Modes of a stellar system I: Ergodic systems
in Monthly Notices of the Royal Astronomical Society
Lau J
(2021)
Erratum: Relaxation of spherical stellar systems
in Monthly Notices of the Royal Astronomical Society
Lau J
(2021)
Modes of a stellar system II: non-ergodic systems
in Monthly Notices of the Royal Astronomical Society
Lee E
(2019)
Exoplanetary Monte Carlo radiative transfer with correlated- k - I. Benchmarking transit and emission observables
in Monthly Notices of the Royal Astronomical Society
Li C
(2022)
Modelling the stellar halo with RR-Lyrae stars
in Monthly Notices of the Royal Astronomical Society
Li C
(2022)
Our Galaxy's youngest disc
in Monthly Notices of the Royal Astronomical Society
Li Z
(2020)
The cross correlation of the ABS and ACT maps
in Journal of Cosmology and Astroparticle Physics
Liu L
(2021)
WISDOM Project - IX. Giant molecular clouds in the lenticular galaxy NGC 4429: effects of shear and tidal forces on clouds
in Monthly Notices of the Royal Astronomical Society
Lu A
(2022)
WISDOM project - XI. Star formation efficiency in the bulge of the AGN-host Galaxy NGC 3169 with SITELLE and ALMA
in Monthly Notices of the Royal Astronomical Society
Macfarlane C
(2021)
The radio loudness of SDSS quasars from the LOFAR Two-metre Sky Survey: ubiquitous jet activity and constraints on star formation
in Monthly Notices of the Royal Astronomical Society
| Title | The Thousand-Pulsar-Array program on MeerKAT -- IX. The time-averaged properties of the observed pulsar population: data set |
| Description | This archive contains pulsar data presented as part of the MNRAS paper: "The Thousand-Pulsar-Array program on MeerKAT -- IX. The time-averaged properties of the observed pulsar population". Folded, time-averaged pulse profiles (4 Stokes parameters, 8 frequency channels, 1024 time bins across the period) of the 1271 pulsars listed in Table 1 of the MNRAS paper are included in the ar_files.zip. Ephemerides of these pulsars (as used in the MNRAS paper) are included in the eph_files.zip. The pulsar data are readable by the PSRCHIVE package, see e.g. van Straten et al., Astronomical Research and Technology 9, 237 (2012). Tables 1, 5, and 6 from the MNRAS paper are included in tables_files.zip as .csv files. The file column_descriptions.txt describes the quantities in columns of these tables. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2022 |
| Provided To Others? | Yes |
| URL | https://zenodo.org/record/7272360 |
| Title | Transit time of K2-146b and K2-146c with K2 and HPF |
| Description | VizieR online Data Catalogue associated with article published in journal Astronomical Journal (AAS) with title 'It takes two planets in resonance to tango around K2-146.' (bibcode: 2020AJ....159..120L) |
| Type Of Material | Database/Collection of data |
| Year Produced | 2020 |
| Provided To Others? | Yes |
| URL | https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/159/120 |
| Description | The MIGHTEE Survey |
| Organisation | University of the Western Cape |
| Department | Department of Physics |
| Country | South Africa |
| Sector | Academic/University |
| PI Contribution | I am the PI of the survey |
| Collaborator Contribution | This is an international collaboration led by myself, manhy members over a range of institutes lead papers based on the data from the survye. This data itself is processed by Ian Heywood in Oxford and science verification is carried out by myself with other members of the Oxford group. |
| Impact | Publications as listed |
| Start Year | 2010 |
| Description | Agile Rabbit |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Talk and discussion on serendipity to art/tech group in Exeter |
| Year(s) Of Engagement Activity | 2021 |
| Description | Ashford Astronomical Society |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Talk on serendipity. |
| Year(s) Of Engagement Activity | 2021 |
| Description | Cafe Scientifique Didcot |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Talk to Didcot Cafe Scientifique online |
| Year(s) Of Engagement Activity | 2021 |
| Description | Chipping Norton Astronomical Society |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Talk to society |
| Year(s) Of Engagement Activity | 2021 |
| Description | Dark Skies Festival Marlborough |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Talk on modern astrophysics. |
| Year(s) Of Engagement Activity | 2021 |
| Description | Dark Sky Wales |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Talk on serendipity |
| Year(s) Of Engagement Activity | 2021 |
| Description | Lols in Space |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Public/other audiences |
| Results and Impact | Stand up comedy |
| Year(s) Of Engagement Activity | 2022 |
| Description | Morning of Theoretical Physics |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Other audiences |
| Results and Impact | A scientific forum run by the theoretical physics sub-department at Oxford University for alumni, students and general public on current topics in theoretical physics. This forum was on gravitational radiation. |
| Year(s) Of Engagement Activity | 2023 |
| URL | https://saturdaytheory.physics.ox.ac.uk |
| Description | North West Science Network Launch Event |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Schools |
| Results and Impact | Outreach talk on astrophysics and cosmology for secondary school students |
| Year(s) Of Engagement Activity | 2019 |
| Description | Norwich Science Festival |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Public/other audiences |
| Results and Impact | Discussion at science festival, released as podcast. |
| Year(s) Of Engagement Activity | 2021 |
| Description | Physics In Action |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Schools |
| Results and Impact | Three talks to large audiences of six formers. |
| Year(s) Of Engagement Activity | 2021,2022 |
| Description | Public presentation |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Oxford University organised a series of presentations in celebration of the 400th anniversary of the Savilian Chairs in Astronomy and Mathematics. I (Steven Balbus) gave a presentation of my work and of the history of black hole research. |
| Year(s) Of Engagement Activity | 2019 |
| URL | https://www2.physics.ox.ac.uk/news/2019/06/21/thinking-3d-in-oxford-physics |
| Description | Saturday mornings of theoretical physics |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | Yes |
| Geographic Reach | National |
| Primary Audience | Public/other audiences |
| Results and Impact | There are always good questions, both after talks and in the coffee & lunch breaks We have a core of regular attendees, and some teachers bring 6th form pupils. |
| Year(s) Of Engagement Activity | 2014 |
| URL | https://www2.physics.ox.ac.uk/research/rudolf-peierls-centre-for-theoretical-physics/saturday-mornin... |
| Description | World Space Week |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Talk on modern astrophysics |
| Year(s) Of Engagement Activity | 2021 |