Galaxies

Supervisor: Michele Cappellari, Chiara Spiniello

One of the key discoveries of the past decade has been that there is some process that is able to suddenly stop star formation (quench) in galaxies. Without quenching, galaxy models are unable to explain the evolution of galaxies over cosmic time. However, the mechanism for quenching is still debated.

In this project, the student will use observations from the MaNGA spectroscopic surveys of local galaxies and observations of distant galaxies with the JWST, as well as observations at intermediate redshift, to trace the evolution of galaxy star formation history. The student will compare the results derived from observations with numerical simulations of galaxy formation, to try to understand the origin of quenching.

Supervisor: Michele Cappellari, Chiara Spiniello

Are you looking for a DPhil project that will challenge you and help you solve one of the biggest mysteries in cosmology? 

The project is part of the TDCOSMO survey (https://obswww.unige.ch/~lemon/tdcosmo-master/), which aims to measure the expansion rate of the Universe (H0) using a novel technique based on strong gravitational lensing, time delay measurements, and stellar galaxy dynamics. This technique is independent of the ones used by supernovae and cosmic microwave background (CMB) observations, which currently disagree on the value of H0 and pose a "crisis" in cosmology (see here). By providing a new and precise measurement of H0, this project will try to resolve this tension and test the validity of the standard cosmological model.

As a DPhil student, you will work with a team of experts from different institutions and use data from the Hubble Space Telescope, JWST, and ground-based integral-field spectroscopy. You will learn how to model gravitational lenses, and galaxy stellar dynamics from spectroscopic data. You will also have the opportunity to participate in international conferences and workshops, collaborate with other researchers, and develop your skills in data analysis, programming, and scientific communication.

Supervisors: Martin Bureau 

This project aims to decipher the intricate structure of bulges, the bright and compact ensembles of billions of stars ruling the centres of galaxies. Bars in particular are known to spontaneously buckle and create bulges that are boxy and peanut-shaped. In turn, classic axisymmetric spheroid models should not fit the data. By combining state-of-the-art observations from optical integral-field (i.e. 3D) spectroscopy with numerical models of bulges, the student will make measurements that directly probe and thus constrain bulge models, unraveling the closely intertwined evolution of bulges and bars in galaxies.
 

The student will be part of the GECKOS project (be bold, be different, be GECKOS!), a deep and high-resolution survey of the stars and ionised-gas of 35 nearby edge-on disk galaxies. GECKOS is based on a guaranteed-time large programme utilising the MUSE optical integral-field spectrograph on the Very Large Telescope (VLT), the premier instrument of its kind in the world, but it also includes a number of ancillary surveys (with e.g. ALMA and CFHT/SITELLE). It has a number of complementary scientific aims, and while the student will be expected to focus on the questions above, participating in any and all activities of the team is possible. Extended working visits to other team members will be encouraged. This project is particularly suited to a student with an interest in observational astronomy and galaxies (structure, dynamics, stellar populations, evolution).

Supervisors: Martin Bureau 

This project aims to decipher the intricate structure of bulges, the bright and compact ensembles of billions of stars ruling the centres of galaxies. Bars in particular are known to spontaneously buckle and create bulges that are boxy and peanut-shaped. Independently, intense star formation is known to lead to gas outflows perpendicular to galaxy discs. By combining state-of-the-art 3D observations of the ionised gas from optical integral-field spectroscopy and molecular gas from millimeter synthesis observations, the student will make measurements that directly constrain the presence of bars and thus the structure of bulges, while simultaneously probing star formation-driven ouflows to large distances. This will untangle the impact of bars and star formation on the evolution of galaxies.

The student will be part of the GECKOS project (be bold, be different, be GECKOS! - see previous project description).

Supervisors: Martin Bureau 

This project aims to unravel the late stages of the formation of galaxies, in particular the build-up of the extended stellar and dark matter halos of spiral galaxies, thought to be dominated by galaxy mergers and accretion events. As the dynamical timescales there are long (several gigayears), the accretion events are imprinted in the galaxies' phase-spaces. Measuring the properties of individual stars beyond our Local Group of galaxies remains extremely difficult, however, so planetary nebulae (PNe) are used instead. These discrete tracers act as lighthhouses, their bright emission lines being detectable/measurable to distances of several tens of megaparsecs. A new generation of wide-field integral-field spectrographs enables us to discriminate PNe from interlopers (such as supernova remnants and star-formation regions), allowing to target spiral galaxies for the first time, and in turn map the composition and kinematics of their halos robustly. In particular, this will relate the PN properties to the usual stellar population properties (age and metallicity), and thus constrain the galaxies' kinematics and luminous+dark matter contents all the way from their centres to their halos.

The student will be part of the SIGNALS project (star-formation, ionised gas and nebular abundances legacy survey), a guaranteed-time programme using the revolutionnary imaging Fourier transform spectrograph SITELLE at the Canada-France Hawaii Telescope (CFHT). SIGNALS exploits several tens of observing nights to study in details over 40 nearby spiral galaxies, and its unprecedented field of view (over 100 times better than its competitors!) allows to simultaneously detect and characterise the PNe across the galaxies. The data are already in hand, as are most of the analysis tools, so the student will dive right into the analysis of the PNe and the scientific interpretation of the data. This project is particularly suited to a student with an interest in observational astronomy and galaxies (structure, dynamics, stellar populations, add evolution).

Supervisors: Martin Bureau 

Understanding the formation and evolution of galaxies is central to much of contemporary astrophysics. The relations between black hole mass and various galaxy properties imply a tight connection between the growth of central supermassive black holes (SMBHs) and that of galaxies, and these relations now underlie a staggering number of observations and simulations. However, the number of reliable SMBH mass measurements is small, and the number of independent measuring methods even smaller. A team led by Prof Bureau has shown that the kinematics of the dense molecular gas of galaxies is the best tracer of their of their masses. Most importantly, following the first SMBH mass measurement published in Nature, the team has now shown that these measurements are both much more accurate and much easier to carry out than with other methods. It is thus time to scale up those efforts and renew our knowledge of SMBHs.

As part of the WISDOM team (mm-Wave Interferometric Survey of Dark Object Masses), the student will use the Atacama Large Millimeter/submillimeter Array (ALMA), the largest ground-based telescope project in existence, to pursue a programme of SMBH mass measurements in a large sample of local galaxies spanning a range of morphological types, masses, and nuclear activities. There are already much data in hand, and the tools necessary to model the data and estimate uncertainties have already been developed, so the student will exploit a well-oiled machinery to make multiple measurements and explore how SMBH masses and galaxy properties correlate. The student will also develop tools to combine this machinery with strong lensing (i.e. apply them to strongly gravitationally-lensed galaxies), to allow SMBH mass measurements beyond the local universe to high redshifts for the first time. The project will thus significantly increase the number of reliable SMBH masses available locally, while yielding the first distant measurements, and it will revolutionise our understanding of SMBH - galaxy co-evolution. This project is particularly suited to a student with an interest in observational astronomy and galaxies (structure, dynamics, evolution).

Supervisors: Martin Bureau 

Understanding how interstellar gas turns into stars is arguably the greatest remaining puzzle in galaxy formation. Stars form in dense gas clouds known as giant molecular clouds (GMCs), but how these emerge, what their structure is, or even whether they are long-lived or transient remains unclear. Previously restricted to our own Milky Way and nearby late-type (i.e. spiral) galaxies, a new generation of telescopes allows studies of GMCs to take an immense leap forward. By probing more diverse galaxies and hitherto inaccessible environments, new laboratories to study star formation are now available.

As part of the WISDOM team (mm-Wave Interferometric Survey of Dark Object Masses), the student will use the Atacama Large Millimeter/submillimeter Array (ALMA), the largest ground-based telescope project in existence, to study GMC populations in a large sample of galaxies spanning a range of morphological types, masses, and nuclear activities. There are much data in hand already, and the project aims to refine and develop the tools required to characterise individual GMCs and thus infer the properties of entire GMC populations. In particular, the student will for the first time probe individual clouds orbiting SMBHs deep within spheroids, measuring their sizes, luminosities, and dynamics, and constraining their evolutionary histories. This is essential to establish whether the properties of GMCs are universal, or whether they are affected by the SMBHs and galaxy properties, in turn impacting their ability to form stars or otherwise feed the SMBHs. By significantly increasing the number of galaxies with GMC censuses, the project will revolutionise our understanding of GMC formation and evolution. This project is particularly suited to a student with an interest in observational astronomy and galaxies (structure, dynamics, interstellar medium, star formation, evolution).

Supervisors: Andy Bunker

There is a project available to work with Prof Andy Bunker on studying distant galaxies with the James Webb Space Telescope, which successfully launched at the end of 2021. Prof Bunker is on the European Space Agency Instrument Science Team for NIRSpec, the near-infrared spectrograph on JWST, has guaranteed time observations which are being gathered now, early in the mission. This project will involve analysing observations and there are several science goals including measuring the spectroscopic redshifts of candidate distant galaxies, and studying the stellar masses, ages and star formation rates in galaxies when the universe was less than 10% of its current age. 

See examples of papers from our JWST Deep Extragalactic Survey (JADES):
https://ui.adsabs.harvard.edu/abs/2023arXiv230602467B/abstract
https://ui.adsabs.harvard.edu/abs/2023A%26A...677A..88B/abstract

Supervisors: Gavin Dalton

This project will look at aspects of the development of calibration and alignment strategy for the focal plane structure of the MOSAIC spectroscopic instrument for the 39m ELT. The MOSAIC focal plane will host 275 robotic positioners, each with an optical relay and compensation optics to mitigate the effects of atmospheric dispersion, which focus the ELT beam onto groups of optical fibres. A first build of the prototype focal plane will commence in early 2025. The MOSAIC science team are now also obtaining prototypical observations with WEAVE at the 4.2m William Herschel Telescope that will be used to explore the data processing stages needed to ensure MOSAIC’s full potential, and there are further opportunities to work on analysis of high redshift galaxy spectra that will combine spectra from WEAVE with near-infrared spectra from the Euclid satellite mission. Within the scope of these works there are multiple opportunities to study aspects of instrumentation and the links from instrument design through advanced data processing and astrophysical analyses.

Supervisors: John Magorrian

Most of the ongoing large-scale surveys of our Galaxy focus on its stellar content, but the gas and dust between the stars offer a richer and more illuminating complementary probe of Galactic structure and evolution. ISM cartography is challenging because, unlike stars, we don't have direct estimates of distances to dust clumps or gas clouds or other ISM features. Instead, the three-dimensional dust distribution has to be gleaned -- statistically -- from the reddenings of individual stars. Meanwhile, the distribution of gas clouds within the Galactic midplane can be constrained from their line-of-sight component of velocities, provided we know the Galaxy's

(nonaxisymmetric) rotation curve (e.g., from simple hydro simulations with an adjustable bar+spiral potential). Each of these methods on its own produces degenerate results, but we ought to be able to do much better by coupling them, because observations of other galaxies tells us that dust tends to coincide with the densest regions of gas.

An added bonus is that it will furnish us with constraints on the Galactic potential that are completely independent of stellar kinematics.

This project will investigate various schemes for mapping dust and gas (and masers and PAH and ...) simultaneously, starting with simplified toy models before applying to real data.

Further reading:

• Sale & Magorrian (2014), "Three-dimensional extinction mapping using Gaussian random fields", MNRAS 445 256 https://ui.adsabs.harvard.edu/abs/2014MNRAS.445..256S/abstract
• Sormani, Binney & Magorrian (2015), "Gas flow in barred potentials - III. Effects of varying the quadrupole ", MNRAS 454 1818 https://ui.adsabs.harvard.edu/abs/2015MNRAS.454.1818S/abstract

Supervisors: Dimitra Rigopoulou

Supermassive black holes (SMBHs) residing in the centres of galaxies experience phases of intense gas accretion becoming (the well-known) Active Galactic Nuclei (AGN). During these growth episodes, enormous amounts of energy are released which have a significant impact on the evolution of the host galaxy. These processes play a significant role in regulating and even quenching star formation in the galaxy by expelling gas out of the galaxy itself or, preventing the gas from cooling and forming stars. The process by which the energy is injected by the AGN and coupled to the surrounding medium is the so-called AGN feedback. Most theoretical/hydrodynamical simulations include AGN-feedback in order to explain key observations of the galaxy population, such as the tight correlation between black hole mass and bulge. Simulations also postulate the existence of powerful winds launched by the SMBH accretion disk and driven by radiative and mechanical processes. These winds couple to the ISM of the host galaxy and drive massive outflows, potentially removing the gas which fuels star formation. AGN-driven outflows are therefore a manifestation of AGN-feedback. With its unparalleled sensitivity and unprecedented spectral and spatial resolution, the James Webb Space Telescope (JWST) is transforming our understanding of galaxy evolution, by providing a much more detailed look at the mechanism by which the central SMBH influences its host galaxy. Observations of ionic and atomic fine structure lines, rotational and vibrational H2 lines and dust emission features in the near and mid-infrared part of the spectrum are fundamental in determining the effects of AGN-driven outflows on the host galaxy’s gas content. So far, our team has been able to establish the dramatic impact of the SMBH on the host galaxy through JWST observations of a sample of local AGN. It is particularly crucial though to study the effects of AGN-feedback at cosmic noon (z~2) since this redshift corresponds to the peak of star formation and SMBH accretion in the Universe and therefore the energy injected by the central engine into the host galaxy is maximized. We are looking for a motivated DPhil student to join our team. The candidate will employ JWST NIRSpec and MIRI spectroscopy to quantify AGN feedback in a sample of powerful AGN at cosmic noon thereby constraining the impact of the SMBH in the host galaxy at a critical time in galaxy evolution.

Further Reading

• Polycyclic aromatic hydrocarbon emission in galaxies as seen with JWST. D. Rigopoulou, F.R., Donnan, I. Garcia-Bernete, et al., 2024, MNRAS, 532, 1598
• The Galaxy Activity, Torus, and Outflow Survey (GATOS). V: Unveiling PAH survival and resilience in the circumnuclear regions of AGN with JWST. I.Garcia-Bernete, D. Rigopoulou, F.R., Donnan, et al., 2024, A&A, in press (eprint arXiv:2409.05686)
• A high angular resolution view of the PAH emission in Seyfert galaxies using JWST/MRS data. I. Garcia-Bernete, D. Rigopoulou, A. Alonso-Herrero, et al., 2022, A&A 666, L5
• Multiphase feedback processes in the Seyfert galaxy NGC 5643. Garcia-Bernete et al., 2021, A&A 645, 21

Supervisors: Aprajita Verma, Matthias Tecza

Collaborators: Anupreeta More (ICUAA, India), Phil Marshall (SLAC/Stanford USA, Visiting Lecturer at Oxford), Chris Lintott (Oxford)

The phenomenon of gravitational lensing, predicted by general relativity, produces some of the most spectacular astronomical images seen. A single galaxy, group or cluster of galaxies can act as "cosmic telescopes" distorting space-time. They can amplify and magnify the light of distant galaxies lying behind them into multiple images, rings or arcs. The separation or deflection of the lensed images is determined by the total mass (dark and light) of the foreground lensing galaxy and are therefore one of the most direct tracers of mass in the galaxies. In fact, strong gravitational lenses have a diverse range of astrophysical and cosmological applications including weighing galaxies and placing constraints of the Hubble constant and dark energy.

With the advent of the forthcoming Euclid and Vera C. Rubin Observatories, the field of strong gravitational lensing will be transformed as we enter regimes of hundreds of thousands of lenses.  However, generating samples of strong lenses that are complete and pure is highly challenging. Even machine learning (ML) techniques yield samples that have high false positive rates (factors of 10-100). For Rubin & Euclid, a combination of ML discovery algorithms and crowd-assisted visual inspection, that is currently a highly successful means of discovering lenses, will form part of the early survey tasks. 

This DPhil project includes work on lens finding and exploring the nature of the distant lensed high redshift galaxies. For lens finding, the student will work on ongoing Space Warps discovery projects including searches with current wide area surveys and preparations for Euclid and Rubin's Legacy Survey of Space and Time including exploring active learning. For the lensed background sources, the magnification and amplification due to lensing allow fainter galaxies to be studied on smaller scales than would be normally possible. This is a preview to the detailed galaxy science that will be achievable by the next generation of extremely large telescopes and we will explore expectations of what the ELT will achieve using simulations of lensed high redshift sources, multi-source lenses and/or lens substructure in collaboration with colleagues in Durham.  The student will be expected to help and liaise with citizen lensing enthusiasts participating in Space Warps (Paper 1 and 2, NPR Science Friday on the HSC search). 

Supervisors: Julien Devriendt, Adrianne Slyz

The first JWST images of the high redshift Universe, when this latter was less than a billion years old, have uncovered a never-seen-before population of galaxies (Matthee et al 2024, ApJ, 963, 129). Already numbering several hundreds, these galaxies are very red and compact, and hence have been dubbed the "Little Red Dots" (LRDs). The typical Little Red Dot radius is only about 2% that of our own Milky Way. Some are even smaller. Two hypotheses have emerged about what powers them.

In the stars-only hypothesis (e.g. Baggen et al, 2024, arXiv:2408.07745), the LRDs contain massive amounts of stars – up to a 100 billion of them, i.e. approximately the same number as in the Milky Way! This would make them the densest stellar environments ever recorded, raising fundamental questions about how such objects could form in the first place, let alone survive the tremendous supernovae explosions that would inevitably ensue.

In the other, more popular hypothesis, supermassive black holes sit at the centre of the LRDs (e.g. Akins et al, 2024, arXiv:2406.10341). Indeed, most of them display large emission lines in their spectra, potentially created by gas swirling around the black hole at high speed. However, there is a catch. Black hole masses inferred from these observations are too high compared with their host galaxies. In the local Universe, known supermassive black holes typically weigh as much as 0.1% of the total stellar mass present in their host galaxies. By contrast, some of these LRDs harbour a black hole as massive as the entire galaxy! Moreover, unlike ordinary black holes, those in LRDs do not seem to emit X-rays. Even in the deepest high-energy images available to date, where they should be detected, they remain invisible (see e.g. Ananna et al 2024, ApJ, 969, 18).

The potential explanation of such an unusual behaviour is that high density, dusty gas gathers around the black hole, significantly obstructing the central high-energy emission, and/or that the black hole could be pulling in gas at a super-Eddington rate. As for the fact that these black holes are over massive, it might simply indicate that the first black holes in the Universe were already very massive when they formed – about 100,000 times the mass of the sun.  The ratio of black hole mass to host galaxy mass could thus remain high for a long time after formation.

This DPhil project will require the student to combine several advances made by our group in recent years, ranging from full non-equilibrium, primordial, metal, and molecular chemistry network coupled to on-the-fly radiation hydrodynamics (Katz 2022, MNRAS, 512, 348; Katz et al 2022, arXiv:2211.04626) to supermassive black hole growth and feedback (Dubois et al 2014, MNRAS, 440, 2333; Beckmann et al 2019, MNRAs, 483, 3488), cosmic rays and self-consistent radiative dust modelling (Rodriguez-Montero et al 2024, MNRAS, 530, 3617; Dubois et al 2024, A&A, 687, 240). The final outcome of the thesis will see all these ingredients included in cosmological zoom simulations geared to model LRDs as realistically as possible.

Key questions to be answered include: Can supermassive black holes develop early on in proto galaxies when stellar and AGN feedback are considered? If black hole growth is massively suppressed, can extremely dense star formation occur instead? Under what conditions? If black holes can form, can they be obscured by dense gas and dust to such an extent that their X-ray emission is significantly suppressed? In any scenario, do numbers match with observations, i.e. are LRD-like objects very rare or quite common? How much do they contribute to the re-ionisation of the Universe as a whole?

Artist’s conception of a supermassive black hole obscured by a thick dusty torus and with brights jets streaming from the black hole. (Credit Melissa Weiss/CFA)

Supervisors: Boon Kok-Tan, Dimitra Rigopoulou

The millimetre (mm) and sub-mm wavelength regime is crucial for advancing our understanding of the universe. Approximately half of the energy generated by star formation and black hole accretion throughout cosmic history has been absorbed by dust and re-radiated as thermal radiation in the mm/sub-mm and far-infrared bands. Consequently, sub-mm astronomy plays a pivotal role in addressing key questions about planet formation, star formation, galaxy evolution, and large-scale structure formation as part of our broader multi-wavelength observational efforts.

Astronomical observations in the mm/sub-mm range, including the first direct detection of black hole, have only been made possible by the remarkable capabilities of near quantum noise limited Superconductor-Insulator-Superconductor (SIS) heterodyne receivers. These receivers are routinely used on observatories such as the Event Horizon Telescope (EHT), the Atacama Large Millimetre/Submillimetre Array (ALMA), and far-infrared space observatories, enabling high spectral and spatial resolution observations of faint celestial objects. However, significant limitations remain in the use of SIS receivers for upcoming ground-based and space-borne astronomical observations.

Currently, most major mm/sub-mm heterodyne facilities around the world are equipped with only a single-pixel receiver per telescope. Increasing the number of pixels at the focal plane would allow for much faster mapping of extended astronomical objects, making it possible to undertake large observational projects that were previously unfeasible. In short, increasing pixel count is akin to building multiple telescopes, but at a fraction of the cost and effort.

This programme encompasses two complementary scientific aims: the first focuses on developing advanced quantum detectors, while the second centres on an observational project.

On the instrumentation side, we have already built experimental systems to test SIS mixers across the frequency range from 160 GHz to 950 GHz. In this project, we aim to develop a medium-sized 25-pixel heterodyne array with advanced capabilities to split incoming astronomical signals into two orthogonal polarisation states and two distinct sidebands; the latter effectively doubling the observational bandwidth. This design is equivalent to a 100-pixel heterodyne array by traditional standards, but with additional polarisation capabilities – a feat that has not yet been demonstrated. If successfully implemented, this would result in the most powerful heterodyne array ever built. Our ultimate goal is to push this technology into the hundreds-of-pixels range in preparation for the ALMA 2040 upgrade and AtLAST, the largest-ever single-dish sub-mm telescope, which is under consideration for construction in the 2030s.

We are seeking a student to join this exciting venture. Key tasks include: 1) developing the 25-pixel dual-polarisation sideband-separating array receiver, 2) upgrading the existing experimental setup to test the array receiver’s performance, and 3) potentially commissioning the demonstrator array receiver at the James Clerk Maxwell Telescope (JCMT) in Hawai’i.

Observationally, the student will be expected to work on a Galaxy Evolution project focusing on the properties of the ISM (gas and dust) in infrared (IR) luminous galaxies. The project will specifically explore the link between the molecular gas and dust content of IR luminous galaxies.  ALMA has made significant progress by providing a census of the cold molecular gas and dust continuum emission in these galaxies. However, little is known about their properties.  For this purpose, we will use the unparalleled capabilities of JWST to probe the emission from PAHs (Polycyclic Aromatic Hydrocarbons) which are a key diagnostic of the ISM as they regulate its thermal and chemical balance. The project will involve reduction and analysis of spectroscopic data from large millimetre and submillimetre observatories, in particular NOEMA and ALMA as well as spectroscopic observations with JWST MIRI and NIRSpec.

This project is ideal for a student who enjoys engaging with theoretical work on quantum sensors, superconducting electromagnetism, and cutting-edge astrophysical developments, while also being enthusiastic about coding, lab-based experiments, and data analysis. Our state-of-the-art cryogenic detector laboratory provides excellent facilities, and the student will be supported by a technician, postdocs, and supervisors, with access to commercial and custom software for research purposes.

Further Readings: 

• https://iopscience.iop.org/article/10.1088/1361-6668/acca51/pdf
• https://ora.ox.ac.uk/objects/uuid:d19a2b82-b5b9-416f-b098-ea4bd4d96ed6/files/smg74qn32h
• https://ui.adsabs.harvard.edu/abs/2022MNRAS.512.2371H/abstract
• https://arxiv.org/pdf/2202.10576.pdf 

Note: A similar project with slightly different focus can be found on the ALP post-graduate page:
https://www.physics.ox.ac.uk/study/postgraduates/dphil-atomic-and-laser-physics/dphil-projects

Supervisors: Boon Kok-Tan, Dimitra Rigopoulou

The development of superconducting parametric amplifiers (SPAs) has garnered significant attention from the astronomical, quantum computing, and dark matter search communities. SPAs offer quantum-limited sensitivity across a broad bandwidth, coupled with ultra-low heat dissipation, making their performance superior to the state-of-the-art cryogenic low-noise amplifiers currently used in these fields. While many prospective innovations remain to be explored, SPAs certainly have the potential to revolutionise many ultra-sensitive instrumentations, particularly in astronomy and quantum computing, operating from microwave to terahertz wavelengths.

SPAs can significantly enhance the sensitivity of heterodyne receivers and enable the development of large astronomical arrays, potentially thousands of pixels while most current sub-mm telescope equipped with only a few pixels. Their large bandwidth, high power handling, and quantum-limited noise performance will have a profound impact on quantum computing architecture, improving the fidelity needed to process hundreds of qubits. This, in turn, could accelerate progress towards practical quantum computing and boost the speed of axion dark matter searches.

This programme comprises two complementary research areas: the development of quantum amplifiers and an observational project.

On the instrumentation side, the student will begin by studying the theoretical foundations and learning to use commercial electromagnetism software, along with in-house codes, to design the amplifiers. They will also have the opportunity to participate in device fabrication using state-of-the-art clean room facilities, either at Oxford or with collaborators at Paris Observatories, CalTech/JPL, and IRAM etc. Additionally, the student will gain hands-on experience with sub-Kelvin cryogenics and novel experimental techniques to measure the performance of the amplifiers, specifically investigating sensitivity and gain across the microwave and millimetre ranges. Ultimately, the student will integrate the amplifier into existing astronomical receivers, quantum computing architectures (in collaboration with Condensed Matter Physics), and the UK Dark Matter Search experiment, assessing their impact on overall system performance.

Observationally, the student will be expected to work on a Galaxy Evolution project focusing on the properties of the ISM (gas and dust) in infrared (IR) luminous galaxies. The project will specifically explore the link between the molecular gas and dust content of IR luminous galaxies.  ALMA has made significant progress by providing a census of the cold molecular gas and dust continuum emission in these galaxies. However, little is known about their properties.  For this purpose, we will use the unparalleled capabilities of JWST to probe the emission from PAHs (Polycyclic Aromatic Hydrocarbons) which are a key diagnostic of the ISM as they regulate its thermal and chemical balance. The project will involve reduction and analysis of spectroscopic data from large millimetre and submillimetre observatories, in particular NOEMA and ALMA as well as spectroscopic observations with JWST MIRI and NIRSpec.

This project is ideal for a student who enjoys delving into the theoretical aspects of quantum sensors and superconducting electromagnetism, as well as cutting-edge developments in astrophysics. They should also be comfortable with coding, lab-based experimental work, and data analysis. The Superconducting Quantum Detector Group at Oxford offers a well-equipped laboratory with all the necessary instruments to design and test quantum devices. The student will receive support from an experienced technician and collaborate with post-docs, other DPhil students, and experts in electronics, mechanics, and photo-fabrication. Access to both commercial and proprietary software will be provided to facilitate their research.

Further Readings: 

• https://www.nature.com/articles/nphys2356, http://science.sciencemag.org/content/350/6258/307
• https://ui.adsabs.harvard.edu/abs/2022MNRAS.512.2371H/abstract
• https://arxiv.org/pdf/2202.10576.pdf