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.
Organisations
Publications
Aigrain S
(2023)
Gaussian Process Regression for Astronomical Time Series
in Annual Review of Astronomy and Astrophysics
Zhao Lily L.
(2022)
The EXPRES Stellar Signals Project II. State of the Field in Disentangling Photospheric Velocities
in arXiv e-prints
Zicher Norbert
(2022)
One year of AU Mic with HARPS: I - measuring the masses of the two transiting planets
in arXiv e-prints
Duncan Christopher A. J.
(2021)
On cosmological bias due to the magnification of shear and position samples in modern weak lensing analyses
in arXiv e-prints
Joudaki S.
(2019)
KiDS+VIKING-450 and DES-Y1 combined: Cosmology with cosmic shear
in arXiv e-prints
Collier Cameron A.
(2020)
Separating planetary reflex Doppler shifts from stellar variability in the wavelength domain
in arXiv e-prints
Kuijken K.
(2019)
The fourth data release of the Kilo-Degree Survey: ugri imaging and nine-band optical-IR photometry over 1000 square degrees
in arXiv e-prints
Harper S. E.
(2022)
The C-Band All-Sky Survey (C-BASS): Template Fitting of Diffuse Galactic Microwave Emission in the Northern Sky
in arXiv e-prints
García-Burillo S
(2021)
The Galaxy Activity, Torus, and Outflow Survey (GATOS) I. ALMA images of dusty molecular tori in Seyfert galaxies
in Astronomy & Astrophysics
Krajnovic D
(2020)
Formation channels of slowly rotating early-type galaxies
in Astronomy & Astrophysics
Grandjean A
(2019)
Constraining the properties of HD 206893 B A combination of radial velocity, direct imaging, and astrometry data (Corrigendum)
in Astronomy & Astrophysics
Morabito L
(2019)
The origin of radio emission in broad absorption line quasars: Results from the LOFAR Two-metre Sky Survey
in Astronomy & Astrophysics
Alonso-Herrero A
(2021)
The Galaxy Activity, Torus, and Outflow Survey (GATOS) II. Torus and polar dust emission in nearby Seyfert galaxies
in Astronomy & Astrophysics
Hildebrandt H
(2020)
KiDS+VIKING-450: Cosmic shear tomography with optical and infrared data
in Astronomy & Astrophysics
Schrabback T
(2021)
Tightening weak lensing constraints on the ellipticity of galaxy-scale dark matter haloes
in Astronomy & Astrophysics
Robertson N
(2021)
Strong detection of the CMB lensing and galaxy weak lensing cross-correlation from ACT-DR4, Planck Legacy, and KiDS-1000
in Astronomy & Astrophysics
Maddox N
(2021)
MIGHTEE-HI: The H I emission project of the MeerKAT MIGHTEE survey
in Astronomy & Astrophysics
Ditrani F
(2023)
Stellar metallicity from optical and UV spectral indices: Test case for WEAVE-StePS
in Astronomy & Astrophysics
Pereira-Santaella M
(2020)
Excitation and acceleration of molecular outflows in LIRGs: The extended ESO 320-G030 outflow on 200-pc scales
in Astronomy & Astrophysics
Pereira-Santaella M
(2022)
Low-power jet-interstellar medium interaction in NGC 7319 revealed by JWST/MIRI MRS
in Astronomy & Astrophysics
Donnan F
(2023)
A detailed look at the most obscured galactic nuclei in the mid-infrared
in Astronomy & Astrophysics
Costantin L
(2019)
A few StePS forward in unveiling the complexity of galaxy evolution: light-weighted stellar ages of intermediate-redshift galaxies with WEAVE
in Astronomy & Astrophysics
González-Alfonso E
(2023)
JWST detection of extremely excited outflowing CO and H_2O in VV 114 E SW: A possible rapidly accreting IMBH
in Astronomy & Astrophysics
Bordé P
(2020)
Transiting exoplanets from the CoRoT space mission XXIX. The hot Jupiters CoRoT-30 b and CoRoT-31 b
in Astronomy & Astrophysics
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
Pereira-Santaella M
(2021)
Physics of ULIRGs with MUSE and ALMA: The PUMA project II. Are local ULIRGs powered by AGN? The subkiloparsec view of the 220 GHz continuum
in Astronomy & Astrophysics
Adams E
(2022)
First release of Apertif imaging survey data
in Astronomy & Astrophysics
Pereira-Santaella M
(2024)
The CO-to-H 2 conversion factor of molecular outflows Rovibrational CO emission in NGC 3256-S resolved by JWST/NIRSpec
in Astronomy & Astrophysics
Esparza-Arredondo D
(2021)
The dust-gas AGN torus as constrained from X-ray and mid-infrared observations
in Astronomy & Astrophysics
García-Bernete I
(2022)
A high angular resolution view of the PAH emission in Seyfert galaxies using JWST/MRS data
in Astronomy & Astrophysics
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
Giblin B
(2021)
KiDS-1000 catalogue: Weak gravitational lensing shear measurements
in Astronomy & Astrophysics
Bellocchi E
(2022)
Compact molecular gas emission in local LIRGs among low- and high- z galaxies
in Astronomy & Astrophysics
Asgari M
(2021)
KiDS-1000 cosmology: Cosmic shear constraints and comparison between two point statistics
in Astronomy & Astrophysics
Mahatma V
(2019)
LoTSS DR1: Double-double radio galaxies in the HETDEX field
in Astronomy & 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
García-Bernete I
(2020)
Multiphase feedback processes in the Sy2 galaxy NGC 5643
in Astronomy & Astrophysics
Heymans C
(2021)
KiDS-1000 Cosmology: Multi-probe weak gravitational lensing and spectroscopic galaxy clustering constraints
in Astronomy & Astrophysics
Peralta De Arriba L
(2023)
A radio-jet-driven outflow in the Seyfert 2 galaxy NGC 2110?
in Astronomy & Astrophysics
Grandjean A
(2019)
Constraining the properties of HD 206893 B A combination of radial velocity, direct imaging, and astrometry data
in Astronomy & Astrophysics
Guinot A
(2022)
ShapePipe: A new shape measurement pipeline and weak-lensing application to UNIONS/CFIS data
in Astronomy & Astrophysics
García-Bernete I
(2022)
Torus and polar dust dependence on active galactic nucleus properties
in Astronomy & Astrophysics
González-Martín O
(2023)
The role of grain size in active galactic nuclei torus dust models
in Astronomy & Astrophysics
Alonso-Herrero A
(2020)
Cold molecular gas and PAH emission in the nuclear and circumnuclear regions of Seyfert galaxies
in Astronomy & Astrophysics
Morabito L
(2020)
The origin of radio emission in broad absorption line quasars: Results from the LOFAR Two-metre Sky Survey ( Corrigendum )
in Astronomy & Astrophysics
García-Bernete I
(2022)
A technique to select the most obscured galaxy nuclei
in Astronomy & Astrophysics
Trudeau A
(2020)
The XXL Survey XLII. Detection and characterisation of the galaxy population of distant galaxy clusters in the XXL-N/VIDEO field: A tale of variety
in Astronomy & Astrophysics
Delvecchio I
(2021)
The infrared-radio correlation of star-forming galaxies is strongly M ? -dependent but nearly redshift-invariant since z ~ 4
in Astronomy & Astrophysics
Angus Ruth
(2020)
GProtation: Measuring stellar rotation periods with Gaussian processes
in Astrophysics Source Code Library
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 | 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 |