Dr Christopher McCabe
(Credit: Dr Christopher McCabe)
Dr Christopher McCabe
STFC Ernest Rutherford Fellow, King's College London
Title of Research: Searching for distinctive signature of dark matter
An overwhelming body of observational evidence points to the existence of dark matter, an elusive form of matter that contributes around 84% to the total amount of matter in the Universe. While little is known about the nature of dark matter, there are some important characteristics that have been inferred. For instance, we are confident that dark matter consists of a new, unknown particle that must be described by physics beyond the Standard Model of particle physics. Physicists have come up with a long list of of dark matter candidates, each with distinctive features that open the door to experimental verification. This has motivated the large ongoing experimental programme to detect dark matter in laboratory experiments on Earth. These experiments are trying to measure signals that will help to unravel some of the particle physics properties of dark matter, such as its mass, its life-time and how it interacts with normal matter.
I work in the space between abstract theories and experimental efforts to detect dark matter, in an area called particle physics phenomenology. I have collaborated closely with experimental colleagues working with a variety of experiments that are searching for distinctive signatures of dark matter. This includes ‘collider physicists’ working on the Large Hadron Collider; ‘low-background physicists’ searching for ultra-rare collisions of dark matter with atoms on the XENON and LUX-ZEPLIN experiments; and ‘cold atom physicists’ searching for the effect of dark matter on the quantum superposition of strontium atoms on the AION atom interferometer project. My research involves proposing new search strategies and coming up with different ways to interpret the data to tell us more about dark matter. This is an exciting area; I can see that my research has real impact, influencing the way that experiments are performed and their data interpreted.
(Credit: Daniel Verscharen)
Dr Daniel Verscharen
STFC Ernest Rutherford Fellow, Mullard Space Science Laboratory, University College London
Title of Research: Thermodynamics of Astrophysical Plasmas: Macroscopic Effects of Collisionless Microphysics
Almost all of the visible matter in the Universe is in the plasma state. This includes the stars, the gas between the stars, accretion discs in active galactic nuclei, and the medium between the galaxies in galaxy clusters. Even our own cosmic neighbourhood is filled with this type of matter: the solar wind is a plasma flow that continuously leaves the Sun’s outer atmosphere and runs through the space between the planets. The solar wind is the only unbounded astrophysical plasma that we can study in great detail through in-situ spacecraft measurements. This accessibility of the solar wind makes it a unique testbed to compare our theoretical predictions for plasma behaviour with an actual astrophysical plasma.
In my research, I combine analytical plasma theory with cutting-edge numerical supercomputer simulations and in-situ data from spacecraft that measure the solar wind. Using this cross-disciplinary approach, my project focuses on three outstanding science themes in the fields of space and astrophysical plasma physics: The first theme addresses the evolution of waves, turbulence, and instabilities in a collisionless plasma. The second theme investigates the effects of electrons on the overall evolution of the plasma. The third theme of my research centres on the effects of turbulence with the goal to explain the heating of the solar corona and the acceleration of the solar wind.
The science themes of my project also lie at the heart of the objectives for ESA’s Solar Orbiter mission. This spacecraft’s successful launch in 2020 has been a transformative step forward for the fields of space plasma physics and solar physics. Especially the combination of its in-situ plasma data and its remote-sensing observations of the Sun will enable us to understand the physics of the solar wind, its source regions and evolution, and its impact on Earth and our society.
(Credit: Tony Hoare)
STFC Ernest Rutherford Fellow, University College London
Title of Research: Precision cosmology at high redshift with the Lyman-α forest
The study of the large-scale structure of the Universe can answer some of the most important and challenging questions in physics: the nature of the dark energy causing the acceleration of the Universe; the inflationary origin of the density fluctuations; the physical properties of the dark matter component; and the number of neutrino species and their mass.
In order to address these questions, several international collaborations are building new instruments to map larger and larger cosmological volumes. The rapid increase of the data sets challenges stablished data analysis techniques, and the sub-percent level of precision of future surveys will require a similar level of control of systematic errors.
The front-runner in the race to map the Universe is the Dark Energy Spectroscopic Instrument (DESI), that in early 2020 started collecting optical spectra of millions of galaxies and quasars per year. The main goal of DESI is to make very precise measurements of the expansion of the Universe as a function of redshift (or time), going all the way to redshift z=3, where the Universe was only 20% of its current age.
During my ERF at UCL, I am developing the analysis tools and the theoretical modelling required to fully exploit the large data sets that DESI will provide. In particular, I use absorption features detected in the spectra of high-redshift quasars to map the distribution of hydrogen in the Universe, and use these maps to study the expansion of the Universe at the highest redshifts.
Dr Dominic Walton
STFC Ernest Rutherford Fellow, University of Cambridge
Title of Research:Title of Research: Black Holes and Accretion: Observational Frontiers
Black holes are primarily found in two main flavours, and are prevalent throughout the universe. Supermassive black holes (SMBHs) reside at the centre of every major galaxy, and large numbers of smaller stellar-remnant black holes (the evolutionary end-point for the most massive stars) are scattered throughout them. Owing to their nature, we primarily see black holes when they are actively accreting; as the infalling material loses its gravitational potential vast amounts of radiation are produced, to the extent that accreting SMBHs can be (perhaps counterintuitively) among the most luminous objects in the universe. Although black holes are remarkably simple objects - a black hole is fully defined by its mass and its spin/angular momentum - there is much that we still do not understand about these enigmatic objects, and the physics of the accretion process is highly complex. Critically, we do not understand quite how SMBHs grew to be so massive. We also see that some black holes can launch extreme jets of material from their accretion flows that are accelerated to relativistic velocities. These jets can significantly influence their surroundings ('feedback'), but we do not fully understand how they are launched.
I use observations of accreting black holes, primarily in the X-ray band, to study these issues (among others). One of my primary aims is to study the innermost regions of the accretion flow around active black holes, as this allows us to constrain the fundamental properties of black holes themselves (mass and, in particular, spin). The growth history of SMBHs is imprinted on their spin distribution, and one of the leading models for jet launching is that these outflows can harness the energy associated with the angular momentum of the central black hole. Measurements of black hole spin therefore offer a rare window into both of these issues.
In addition, I also work extensively on understanding accretion at extreme rates. We are now seeing that SMBHs were already present when the universe was still in its infancy (< 1 Gyr old), requiring very rapid assembly. This process cannot currently be observed directly (local SMBHs are not growing nearly as rapidly), so instead we try to use local stellar remnants accreting at extreme rates, otherwise known as ultraluminous X-ray sources (ULXs), as proxies to understand this accretion regime (although the physics of accretion is complex, it is largely 'scale-invariant', meaning it does not depend on the mass of the accretor). However, the situation has potentially been complicated by our recent discovery that at least some of the most extreme ULXs are actually powered by accreting pulsars, i.e. strongly magnetized neutron stars. Although this does cement these sources as the most extreme accretors known relative to their mass, their magnetic nature potentially introduces significant differences to accreting black holes. It is not well understood how these neutron stars are able to reach such extreme luminosities, and exactly what role their magnetic fields play in this. In addition, it is not well understood what contribution these neutron stars make to the broader ULX population. I am leading observationally-focused projects to understand these remarkable ULX pulsars in order to determine exactly what connections can be made between these sources and early-universe SMBH growth, and to establish whether the majority of all ULXs could actually be neutron stars, contrary to our long-held expectations, or whether a substantial population of black hole ULXs also exists.
Dr Mika Vesterinen
STFC Ernest Rutherford Fellow, University of Warwick
Title of Research:Title of Research: Precision measurements of beauty decays and the W boson mass at LHCb
What are the basic building blocks of the universe and how do they interact at the fundamental level? The Standard Model (SM) contains twelve matter species that interact via force carrying bosons. One area that particularly interests me is flavour, which is one of the main distinctions between the twelve species of matter. Why are there three generations of quarks? Why do they exhibit a hierarchical pattern of masses and mixing parameters? My second area of interest is the electroweak symmetry breaking mechanism that gives mass to the W and Z bosons through their interaction with the Higgs field. Are there additional dynamics beyond the minimal electroweak symmetry breaking description in the SM?
In the quest for a deeper understanding of flavour it is particularly interesting to study hadrons containing beauty quarks because their weak-interaction decays involve all types of flavour-changing quark transitions. Furthermore, these decays are suppressed in the SM, making them intrinsically sensitive to new types of interactions. The LHCb experiment at the LHC sees roughly one billion beauty hadrons per year, enabling measurements of unprecedented precision using processes that have previously been out of reach. I am particularly interested in decays with so-called semileptonic transitions of a beauty-quarks to a charm- or up-quarks. With these semileptonic decays I hope to more precisely determine the quark flavour parameters of the SM, and to see a new type of CP-violation that is strongly suppressed in the SM.
A key test of electroweak symmetry breaking is to precisely measure the W boson mass and compare this measurement to the prediction of the SM. The W mass is notoriously difficult to measure since leptonic W decays, accessible at hadron colliders, involve a neutrino that escapes the detector without a trace. Measurements of the W mass have long been part of the programs of the ATLAS and CMS experiments. They see electrons and muons at large angles with respect to the colliding beams. I plan to make a hitherto unforeseen measurement of the W mass using LHCb, which uniquely reconstructs muons at small angles with respect to the beams. Combing my planned measurement with ATLAS and CMS is somewhat equivalent to having an idealised experiment that covers all angles, which greatly reduces the most challenging sources of uncertainty.
Dr Nicholas Wardle
STFC Ernest Rutherford Fellow, Imperial College London
Title of Research:Characterising the Higgs boson to search for new physics
The discovery of the Higgs boson was the greatest success of the first run of the Large Hadron Collider (LHC) and represented a major landmark in the experimental verification of the Standard Model (SM) of particle physics, our most precise model of fundamental particles and their interactions. Despite the remarkable success of the SM, it is known to be incomplete and fails to answer several basic questions about nature such as, “why are some fundamental particles so much heavier than others?”, and “what exactly is dark matter?”. Many theories, beyond the SM (BSM) have been proposed to answer these questions, but so far none of them have been experimentally confirmed.
In addition to marking the end of a long search for this elusive particle, the discovery of the Higgs boson provided a new opportunity to search for BSM physics. Due to the unique nature of the Higgs boson, being the only fundamental scalar particle we know about, the existence of BSM physics can modify its properties compared to what the SM predicts they should be. My research focuses on performing and using precision measurements of the Higgs boson’s properties at CMS, one of the two general purpose detectors at the LHC, to probe theories of BSM physics.
These measurements require performing very CPU intensive likelihood fits of vast amounts of data arising from different production and decay modes of the Higgs boson. To overcome this challenge, I am also researching statistical techniques to “re-interpret” Higgs boson (and other precision) measurements at the LHC, using a reduced set of information from the data, without losing sensitivity to different BSM theories. This will allow for global interpretations of data from the LHC, which may reveal new physics beyond the SM.
Dr Ryan Milligan
STFC Ernest Rutherford Fellow, Queen’s University Belfast
Title of Research: Modelling and Multi-wavelength Observations of Solar Flare Heating
Solar flares are explosive releases of energy in the Sun’s atmosphere that can have far-reaching consequences across the solar system. Energy that is stored in the Sun’s magnetic field gets liberated and converted into heating and particle acceleration. Precisely how this conversion takes place remains an open question, but the answer is likely to lie in the chromosphere where much of the energy that is released in the corona (believed to be in the form of relativistic particles) gets deposited. This energy deposition results in the heating, and therefore, expansion, of the ambient plasma in the chromosphere, which manifests itself as increased radiation across much of the electromagnetic spectrum. The extreme-ultra violet component in particular has a direct influence on the dynamics and composition of the Earth’s atmosphere, and those of other planets. Similar releases of energy on other stars are just as likely to impact potentially habitable exoplanets. The overarching goal of my fellowship is therefore to use the diagnostic information contained in the radiation emitted during solar flares to understand the underlying energy release and transport processes, and how this leads to enhancements of the Sun’s most geoeffective emission. This in turn can provide insights into similar processes at work across the universe.
My research employs a combination of state-of-the-art numerical modeling with observations taken with our most advanced space-based solar satellites. X-ray data from mission’s such as NASA’s RHESSI spacecraft can tell us a lot about the energetic particles believed to be responsible for driving increased emission in the chromosphere, which we can then study using data from SDO, Hinode, GOES, IRIS, as well as the MAVEN satellite in orbit around Mars. These data can be used to guide and constrain numerical simulations, such as RADYN, which can reveal the underlying physics.
Dr Matthew Middleton
STFC Ernest Rutherford Fellow, University of Southampton
Title of Research: Supermassive black hole growth - a small-scale solution to a large-scale problem
Accretion onto super-massive black holes (SMBHs) leads to mass and energy being transported from scales comparable to our solar system, to those many times larger than our Galaxy, and has been one of the defining influences in sculpting our observable Universe. My research focusses on the most extreme – and least understood – regime of accretion, one which enabled the rapid growth of SMBHs at high redshift. To explore this, I study local analogues called ultraluminous X-ray sources (ULXs) which contain stellar rather than super-massive compact objects. By understanding the physics occurring in ULXs, we can hope to understand analogous accretion onto high redshift SMBHs and the impact on the early Universe – soon to be glimpsed for the first time with JWST.
As part of international collaborations, I observe ULXs across multiple wavebands (radio – X-rays) and, through applying spectral-timing analysis techniques, we are provided with additional power to reveal the fundamental nature of the accretion flow. The result has been new models and a number of important breakthroughs, including the discovery of the tell-tale signature of winds being launched from ULXs at high speeds, providing unique insights into their nature. The discovery of X-ray pulsations from several ULXs has shown that neutron stars must account for some fraction of the ULX population; determining which ULXs host neutron stars and which host black holes is crucial for making direct comparisons to SMBHs. My team is at the forefront of developing new approaches based on the General Relativistic effect of frame-dragging, which we hope will allow us to both locate the black hole systems and test fundamental physics. Once black hole ULXs have been identified, we will be able to test our understanding of extreme accretion through the application of next-generation spectral-timing models obtained from 3D RMHD simulations using time awarded via DiRAC.
Dr Haixing Miao
STFC Ernest Rutherford Fellow, University of Birmingham
Title of Research: Exploring quantum aspects of gravitational-wave detectors
Ground-based gravitational-wave (GW) detectors including Advanced LIGO and Virgo, which recently made breakthrough discoveries, are kilometre scale laser interferometers with kilogram size mirrors as the test masses. Due to extreme weakness of the GW signal, they are among the most sensitive instruments that we have ever built. It turns out that quantum mechanical effects of light (optical field) and its interaction with the test masses (mechanics) introduces quantum noise that limits the detector sensitivity. On the one hand, we need to understand the optomechanical interaction in the quantum regime—quantum optomechanics, and apply quantum-measurement techniques to improve the sensitivity. On the other hand, we can take advantage of such quantum-limited devices to explore quantum behaviours of macroscopic objects—macroscopic quantum mechanics (MQM).
My research has been focusing on these quantum aspects of GW detectors and quantum optomechanical devices in general. With national and international collaborators, we have investigated different quantum techniques to reduce quantum noise, which leads to new detector configurations. Most recently, by studying the fundamental quantum limit, we have found out that the ultimate sensitivity limit comes from the dissipative processes due to losses present in the optics. The next step is coherently combining different techniques to achieve such an ultimate limit, which informs the design of next-generation GW observatories. For MQM, we are looking into the prospects of using quantum optomechanical devices to explore the quantum nature of gravity in table-top experiments.
Dr Chris Nixon
STFC Ernest Rutherford Fellow, University of Leicester
Title of Research: Accretion disc physics: breaking the symmetries
Accretion discs are a critical component in many astronomical systems: they are the birth sites of stars and planets, and they surround supermassive black holes in active galaxies and quasars. These discs form when gas moves on orbits in the gravity field of a star or black hole, balancing the central gravitational pull with the centrifugal effect of rotation. Angular momentum is transported outwards by the action of a viscosity, allowing most of the gas to spirals inwards. This process turns gravitational potential energy into light that we can observe, and is the most efficient way of extracting energy from ordinary matter. In some systems this can be observed across much of the entire visible Universe. Supermassive black hole accretion can outshine galaxies and significantly affect the hole’s surroundings through energy and momentum feedback. When we observe these systems they always show complex time variability, and theoretical models are now starting to produce plausible mechanisms to explain these phenomena.
My research makes use of the DiRAC high performance computing facilities to model accretion discs using Lagrangian- and grid-based numerical methods. These computer simulations are targeted at understanding different astrophysical systems; from the formation and evolution of protostellar discs aimed at understanding the disc conditions at the point at which planets are starting to form, to the evolution of the stellar debris formed in a tidal disruption event where a star passes too close to a supermassive black hole. In each case the theoretical work is motivated by the latest observational data which routinely provides impetus for new ideas and puzzles to be solved.
Dr Pin Wu
STFC Daphne Jackson Fellow, Queen's University Belfast
Title of Research: Magnetic reconnection in astrophysical plasmas
More than 99% of the visible universe, the stars, galaxies and the matter spread between them, are ionised gas, so-called plasma. Most plasmas can be viewed as magnetic field carrying, electrically conducting fluids. The magnetic fields are highly variable: tangled, twisted, and are continuously pushed together or pulled apart with the plasma flow. When pushed together, oppositely directed components of magnetic field lines can break and subsequently reconnect.
Magnetic reconnection can lead to fierce and stormy releases of energy that drive explosive events such as coronal mass ejections and solar flares. The energetic particle bursts from such storms can damage satellites, harm astronauts, disrupt communications, and in extreme cases shut down power grids. Understanding how reconnection occurs and dissipates energy can help us improve our predictive capability for space weather. Outside our solar system, reconnection also operates in accretion disk, supernova, or in the outflows of active galactic nuclei, pulsars or black holes.
The fundamental questions of reconnection centre on why it occurs so violently fast and what triggers its onset. The difficulty in theoretical efforts are due to the nonlinearity of the problems. The principal computational challenge lies in the need of computing resources necessary to cover all the relevant micro- and macro- scales in three dimensions with the appropriate consideration of boundary conditions. In-situ space borne observations are limited by local measurements. To resolve the whole puzzle, requires a complementary approach, that combines theoretical predictions with experimental measurements.
The first part of my research focuses on analysing observations of reconnection related events in the lower solar atmosphere by NASA's IRIS and SDO space missions. Currently, the primary focus of my research is to simulate laboratory laser driven reconnection using the EPOCH code. The aim is to assist future experiments into emerging field of laboratory astrophysics, and to shed light on reconnection dynamics for astrophysics.
Dr Andreas Schmitt
STFC Ernest Rutherford Fellow, University of Southampton
Title of Research: Dense matter in compact stars
Neutron stars - objects with a mass of 1-2 solar masses and a radius of about 10 km - contain the densest matter in the universe. This ultra-dense matter is very different from ordinary matter on earth: the density in the interior of the star is sufficiently large for the atomic nuclei to overlap, and thus fundamental properties of the strong nuclear force become crucial to understand macroscopic, observable properties of neutron stars. Neutron stars are therefore complex systems that are governed by the theory of the strong nuclear force, Quantum Chromodynamics (QCD).
My research is centred around this "condensed matter physics of QCD", both from a theoretical perspective and from an astrophysical point of view. The theoretical aspects concern for instance the structure of the QCD phase diagram, which is poorly known because even brute force calculations fail in the regime of large baryon densities. One fundamental question is at which density the deconfinement transition occurs and whether it is a discontinuous phase transition. The astrophysical version of this question is whether there is deconfined quark matter in the core of the neutron star or whether the star is made entirely out of nuclear matter. I am addressing this question with various theoretical methods, for instance employing the so-called gauge/gravity correspondence or using effective theories and phenomenological models to describe nuclear and quark matter.
As in usual condensed matter systems, the phase structure of dense QCD is expected to be very rich. Nucleons and quarks can form Cooper pairs similar to electrons in ordinary superconductors. Therefore, neutron stars may host complicated superfluid and superconducting interiors, including magnetic flux tubes and superfluid vortices. I am investigating these phases and their hydrodynamic properties, trying to understand and explain various astrophysical observations, such as pulsar glitches or the cooling behaviour of neutron stars. Understanding microscopic, fundamental physics from neutron stars is an exciting field of research also because of the recent discovery of gravitational waves from a neutron star merger, which opens up new possibilities to improve our knowledge of the condensed matter physics of QCD.
Dr Erminia Calabrese
STFC Ernest Rutherford Fellow, Cardiff University
Title of Research: Precision cosmology from early and late-time surveys
Our best understanding of the origins and evolution of the Universe is driven by observations of the Cosmic Microwave Background (CMB), a relic light that has been travelling for almost 14 billion years since the Big Bang. Over the last two decades, CMB data have led the establishment of a standard model of cosmology, ‘ΛCDM’: we live in a geometrically flat Universe filled with photons, neutrinos, normal baryons and mysterious dark components (dark matter and dark energy). Cosmic structures were seeded by tiny initial density ripples thought to be stretched to cosmological scales during ‘cosmic inflation’ and then grown under gravity. Although supported by many astrophysical and cosmological data, this model is heavily incomplete from a theoretical point of view: did cosmic inflation really happen? If yes, what drove it? What is the nature of dark matter and dark energy? What is the absolute mass scale of neutrinos? My research spans theoretical work and statistical data analysis of state-of-the-art CMB data to answer these fundamental questions.
The CMB has been recently mapped with unprecedented precision by the ESA’s Planck satellite. The final Planck data provide strong support to the ΛCDM model and constrain its basic parameters to sub-percent accuracy. The next steps in CMB cosmology are now driven by improved measurement of CMB polarization from ground-based telescopes, including ACT (the Atacama Cosmology Telescope). Alongside CMB data, observations of galaxies’ shape and distribution test the physics of the local Universe (i.e. of the last 10 billion years). Combining CMB and galaxy data is crucial to reduce the impact of instrumental and astrophysical systematics and to distinguish physical processes which would be otherwise degenerate.
As part of my ERF work, I contribute to the analysis of the Planck data and lead data characterization and scientific exploitation of ACT CMB data, alone and in combination with galaxy data.
Dr Andrew Hillier
STFC Ernest Rutherford Fellow, University of Exeter
Title of Research: Magnetism and Fluid Flows in our Solar-Planetary Environment
Solar prominences (otherwise known as filaments) are one of the most fascinating structures in the solar atmosphere. They can be observed as cloud-like features that are comprised of relatively cool plasma (10,000 K) embedded in the hot corona (1,000,000 K) which is supported against gravity by the magnetic fields that permeate the solar atmosphere. The eruption of prominences lead to coronal mass ejections (a collection of mass and magnetic field violently ejected from the Sun) which are of great importance for their space weather effects.
The launch of the Hinode satellite in 2006 followed by the Interface Region Imaging Spectrograph (IRIS) in 2013 provided new eyes with which to look at the solar atmosphere, and the wavelengths of light (some of which are emitted by plasma around 10,000K) under study by these missions made them perfect for observing prominences. These observations have revolutionised our understanding of prominences, showing that prominences can be highly dynamic across all their observable spatial and temporal scales, making them a wonderful laboratory to study magnetised fluid dynamics. However, in many cases the physical processes behind these dynamics are still to be made clear. My fellowship is about both theoretically and observationally understanding these dynamics and determining their effects across the observed scales of the prominence and beyond.
A key component of my work in determining how instabilities and other processes can create these wonderful dynamics comes from the fact that prominence plasma mainly consists of neutrally charged atoms that cannot directly interact with the magnetic field. The way these neutral species can experience magnetic forces is indirectly, by colliding with charged species resulting in an exchange of momentum. So as part the turbulent motions in prominences driven by magnetic forces, it is important to comprehend how the neutrals respond, and how this changes, for example, the heating in the plasma. However, my focus is not only on these, relatively speaking, small spatial and temporal scales. The impact of all the observed dynamics may be important in determining how the prominence system can slowly evolve to become unstable and erupt (i.e. through a huge number of tiny motions producing a big change), and I am also looking into this process.
Dr Timothy Davis
STFC Ernest Rutherford Fellow, Cardiff University
Title of Research: The cycle of life, death and rebirth in massive early-type galaxies; star formation, black holes and feedback
My research focuses on understanding the most massive galaxies in the local universe. These objects are made up of billions of old stars, have red optical colours, and are generally thought to be free of cold gas - the fuel for new stars. Thus they are often described as ”red and dead”. Astronomers still don’t know what caused these galaxies to die, or if they can come back to life again.
One of the ways astronomers think that massive galaxies become ”red and dead” is due to supermassive black-holes. These enigmatic objects are ubiquitous, and strongly linked to galaxy formation, as they seem to grow in step with their galaxy host. In order to understand the role of black holes in the formation of galaxies I have developed a new technique to measure their masses, by tracing the motions of molecular gas clouds swirling around them. As an Ernest Rutherford fellow, one of my main activities is leading a team of researchers using extremely high spatial resolution data from ALMA (the Atacama Millimetre/Submillimetre Array) to reveal the dark monsters lurking at the hearts of nearby galaxies.
Massive galaxies, like the ones I study, don’t have to stay ”red and dead” forever. They can come back to life if material from dying stars cools, becoming fuel for a new generation of stars. They can also merge with other small galaxies and steal their gas. As part of my research I study these processes, revealing that around 1/4 of the massive ”red and dead” galaxies around us today are currently in the process of being reborn. These regenerated galaxies don’t seem to be using this new fuel very effectively, however, and form stars very inefficiently when compared to galaxies like our own Milky Way. As a Rutherford fellow I aim to find out why this is happening, and what this can tell us about the physics controlling star formation across the universe.
Dr Kate Maguire
Lecturer and STFC Ernest Rutherford Fellow, Queen's University Belfast
Awarded ERF 2015
Title of Research: Understanding cosmological probes: constraining the progenitors and diversity of Type Ia supernovae
Supernovae are the extremely bright explosions resulting from the violent deaths of stars. They have a major influence on many areas of astrophysics but they are perhaps best known for their use in measuring distances in the Universe. The homogenous nature of a particular type of exploding star, Type Ia supernovae, led to the discovery of the mysterious cosmological quantity, dark energy, that we now know makes up ~70% of the mass-energy of the Universe but whose origin remains unknown.
Future state-of-the-art surveys (e.g. the European Space Agency mission, Euclid and the Large Synoptic Survey Telescope, LSST) are being designed to constrain theories of dark energy using larger supernova samples. However, to distinguish between these theories, it is very important to understand the elusive properties of the supernovae themselves. This is the aim of my Ernest Rutherford fellowship.
Surprisingly despite their use in precision measurements of dark energy, we still do not understand the stellar systems that explode as Type Ia supernovae. Key questions to be addressed include: 'Is there more than one way to make a Type Ia supernovae?', 'How exactly do they explode?' and 'How do the properties of the galaxies within which they explode affect their explosions?'.
My aim is not only to unveil the stellar systems that explode as Type Ia supernovae but also to understand how their properties may evolve throughout the Universe. In the earlier Universe, galaxies had different properties to those forming today, which has been shown to have a subtle, but measurable, influence on the properties of Type Ia supernovae.
I am using data from some of the world's largest telescopes at the European Southern Observatory (ESO) in Chile, combined with theoretical modelling of their explosions, to understand the origin of Type Ia supernova and constrain their diversity. This project is very timely with the potential for significant breakthroughs in Type Ia supernovae research to be made before the next-generation transient survey, LSST, begin in ~2021.
|Dr James Aird||University of Leicester|
|Dr Matteo Agostini||University College London|
|Dr David Alonso||University of Oxford|
|Dr Nicola Amorisco||Durham University|
|Dr Patrick Antolin||Northumbria University|
|Dr Fabio Antonini||Cardiff University|
|Dr David John Armstrong||University of Warwick|
|Dr Janet Elizabeth Bowey (Returner)||Cardiff University|
|Dr Robert Burston (Returner)||University of Bath|
|Dr Erminia Calabrese||Cardiff University|
|Dr Sarah Casewell||University of Leicester|
|Dr Christopher Chen||Queen Mary University of London|
|Dr Thomas Collett||University of Portsmouth|
|Dr Richard Andrew Davison||Heriot-Watt University|
|Dr James Dobson||University College London|
|Dr Joanna Katy Eberhardt||Imperial College London|
|Dr Gabriel Facini||University of Warwick|
|Dr Andreu Font-Ribera||University College London|
|Dr Liam Gaffney||University of Liverpool|
|Dr Lucia Grillo||The University of Manchester|
|Dr Saso Grozdanov||Queen Mary University of London|
|Dr Masanori Hanada||University of Southampton|
|Dr Lucian Harland-Lang||University of Oxford|
|Dr Joachim, Harnois-Deraps||Liverpool John Moores University|
|Dr Caitriona Jackman||University of Southampton|
|Dr Matthew Kenzie||University of Warwick|
|Dr Jonas Lindert||University of Sussex|
|Dr David Long||University College London|
|Dr Xianguo Lu||University of Oxford|
|Dr David Marsh||Kings College London|
|Dr Christopher McCabe||King's College London|
|Dr Paul McFadden||Newcastle University|
|Dr Haixing Miao||University of Birmingham|
|Dr Matthew Middleton||University of Southampton|
|Dr Ryan Milligan||Queens University Belfast|
|Dr Rachel Montgomery||University of Glasgow|
|Dr Christopher Nixon||University of Leicester|
|Dr Johannes Noller||University of Cambridge|
|Dr Steven Parsons||University of Sheffield|
|Dr Karolos Jozef Potamianos||University of Oxford|
|Dr Darren Price||The University of Manchester|
|Dr Giovanni Pietro Rosotti||University of Leicester|
|Dr Giuseppe Ruggiero||Lancaster University|
|Dr Helen Russell||University of Nottingham|
|Dr Andreas Schmitt||University of Southampton|
|Dr David Keith Sharp||The University of Manchester|
|Dr Blake Sherwin||University of Cambridge|
|Dr Renske Smit||Liverpool John Moores University|
|Dr Rowan Smith||The University of Manchester|
|Dr Romain Tartese||The University of Manchester|
|Dr David Vegh||Queen Mary University of London|
|Dr Dimitri Veras||University of Warwick|
|Dr Daniel Verscharen||University College London|
|Dr Mika Vesterinen||University of Warwick|
|Dr Eleni Vryonidou||University of Glasgow|
|Dr Dominic Walton||University of Cambridge|
|Dr Nicholas Wardle||Imperial College London|
|Dr Julie Wardlow||Lancaster University|
|Dr Mark Whitehead||University of Bristol|
|Dr Nicholas Wright||Keele University|
|Dr Nicholas Zachariou||University of York|
|Dr Svitlana Zhukovska||University of Exeter|
On 5 March 2018 STFC held its second Introductory Workshop for newly appointed Ernest Rutherford Fellows. Thank you to those who participated in the event.
The agenda together with links to the speaker presentations are now available to view.
Last updated: 01 July 2020