Funding was successfully secured for collaboration with external partners to develop a biofilm model for testing active ingredients for hand hygiene.
Biofilm research
A number of our researchers are involved in work relating to preventing, detecting, managing or engineering biofilms. Biofilms are communities of microbes, and they can have an enormous impact on human life and the health of the planet.
Testing of skin disinfection formulations
There is a need for simple, affordable and effective procedures for screening hand disinfectant products. Dr Susana Direito the lead and Principal Investigator of the project will work with colleagues from the School’s Institute for Condensed Matter and Complex Systems (Aidan Brown, Job Thijssen, Andreia Fonseca da Silva and Paul Hush), and industrial partners Bear Valley Ventures (Walter Gibson) and Aqualution Systems Limited (Nick Meakin and Michelle Lewis), to develop a human skin biofilm model that can be used for high-throughput testing of novel skin disinfection formulations. It is hoped that use of the model will lead to the development of new hand hygiene products to improve health around the world.
Project funding
Funding for this project was received from the National Biofilms Innovation Centre (NBIC) as part of their forth Proof of Concept. A total of 18 biofilm-related projects have been funded by NBIC during this latest round, which cover a wide range of sectors including health, hygiene, industrial processing, food, water, oral care, personal care, anaerobic digestion, waste and wastewater and biotechnology.
Astronomers have shed light on the mystery of why some galaxies look blue while others appear red.
Galaxies exhibit many different features, in terms of size, shape and colour. The most distinguishable separation, known since the time of Edwin Hubble, is into two families: blue star-forming spiral galaxies, and red non-star forming elliptical galaxies. How they end up in this bimodality is, to this day, a major question in galaxy formation.
In general, astronomers believe that red galaxies live in massive dark matter halos, while blue galaxies live in more moderate-mass ones. But recent observations suggest that both types of galaxies can be hosted by even the same halo mass, and blue galaxies have more stars than red ones. Why does this trend exist, and is it telling us something fundamental about the origin of the colour bimodality? Many previous galaxy formation models have failed to reproduce this observed trend. In contrast, the state-of-the-art SIMBA simulation (figure 1), led by the Institute for Astronomy’s Dr Weiguang Cui, is remarkably successful.
Encouraged by this success, Dr Cui and the team of researchers explored how the colour bimodality originates by tracking individual simulated galaxies back in time. It was revealed that this bimodality originates in differences between their host halo mass growth history, called halo assembly bias (left panel on figure 2), and its unexpected interplay with SIMBA’s unique models that quench galaxies using the energy released from black hole growth.
Differences in the way the dark matter halos – a key building block of galaxies – develop over time influence which type of galaxy will form and the number of stars they contain. The team found that halos with the same mass that formed earlier tend to contain blue galaxies while those that formed later usually contain red ones. The team also found that the way energy is released from black holes – which are found at the centre of every galaxy – is crucial. How this happens affects whether a galaxy will be blue or red, researchers say. The findings show that halos formed later will result in their galaxies with less gas, which causes black holes to emit huge amounts of energy that stops the formation of new stars. By contrast, halos that formed earlier contain more gas, which causes black holes to release less energy and does not prevent new stars forming.
SIMBA thus provides a significant step forward in understanding the physical origin of galaxy bimodality, by connecting large-scale structure formation with small-scale processes of black hole growth and feedback.
Prof John A. Peacock said, “We are working with one of the most sophisticated numerical models of galaxy formation, and it’s really encouraging to see that the new details in the simulation produce galaxies that look more and more like those in the real universe”.
Prof Romeel Dave added, "Such increasingly realistic simulations give us confidence that we are moving towards understanding how the billions of galaxies we see in a variety of shapes, sizes, and colours formed out of the primordial soup of the Big Bang."
The research, published in the journal Nature Astronomy, was funded by the European Research Council, Royal Society and Science and Technology Facilities Council.
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Puzzles, tours and a play about psychology and quantum physics: some of the School’s events this year.
A packed programme of online and in-person events celebrating the power of science and the importance of connection has been unveiled by the organisers of the citywide festival.
It will feature more than 200 events, tours, exhibitions, workshops for children, young people and adults, of which 70 per cent are available online and free to access to anyone around the world.
The festival – the world’s first and Europe’s biggest – has this year moved away from its usual Easter holiday dates to take place online and in person between 26 June and 11 July.
The School of Physics and Astronomy is involved in a number of activities: solve our science puzzles; take a self-led tour and learn about biofilms; virtually explore the James Clerk Maxwell building to learn about the work we do and meet some of our students and staff.
Congratulations to Dr Cheryl Patrick who has been awarded an Ernest Rutherford Fellowship.
The STFC (Science and Technology Facilities Council) Ernest Rutherford Fellowships enable early career researchers with clear leadership potential to establish a strong, independent research programme. We are pleased that successful candidate Dr Patrick will be starting with us in October.
Dr Patrick will be based in the School’s Institute for Particle & Nuclear Physics. Her research focuses on neutrinos: light, neutral particles with behaviours beyond the Standard Model of particle physics. As we can only learn about neutrinos through their interactions with matter, she’ll be studying how nuclei affect our understanding of neutrinos in various experiments, and how those experiments might be able to help each other.
Congratulations to Dr XinRan Liu who has received a British Science Association Award Lecture for Physical Sciences and Mathematics.
British Science Association Award Lectures
The British Science Association has announced its Award Lectures winners for 2021. Dr XinRan Liu is the Award Lecture winner for Physical Sciences and Mathematics. These awards are given to UK researchers in recognition of their work and commitment to public engagement efforts. Previous Award Lecturers include Brian Cox, Richard Wiseman and Maggie Aderin-Pocock.
All Award Lecturers create a video where they delve into their research and its real-world implications (link below), and take part in a Q&A event as part of the British Science Festival. The 2021 Festival will be held in Chelmsford from Tuesday 7 to Saturday 11 September.
Dark matter experiment
Dr XinRan Liu is currently a Research Fellow at the School of Physics and Astronomy working on the LUX-ZEPLIN dark matter search experiment. The project is in its final stages of construction at the Sanford Mine in South Dakota and is expected to rapidly become world leading. XinRan specialises in ultra-low background radiation detection and has several leadership roles within the LUX-ZEPLIN experiment including on-site cleanliness during the critically important final construction phase. XinRan is also currently the lead scientist for the Boulby XIA, a world-leading surface radiation detector.
Next generation of scientists
Outside of his research, Dr XinRan Liu has huge enthusiasm for public engagement, his most remarkable outreach activity to date being the “Remote3” project which he conceived and currently leads the delivery of. This project enables pupils from schools in the most remote parts of Scotland, otherwise underserved in STEM opportunities, to build, program and operate small robots in the STFC Mars Yard at the Boulby Underground Laboratory.
Dr XinRan commented on his work:
Our aim is to inspire the next generation of students into science and have lots and lots of fun whilst doing it!
Searching for the invisible
Dr XinRan’s work focuses on attempting to detect dark matter, one of the most common, yet most mysterious and hard-to-study substances in the field of physics. During the British Science Festival event, he will discuss the extreme lengths that scientists have gone to, in order to find the answers to some of the Universe's biggest questions. From studying the stars millions of miles above us to delving several kilometres below the surface of the Earth, he explains why dark matter could be the key to our understanding of the Universe.
Congratulations to Dr Rosa Santomartino who has been awarded a Leverhulme Trust Early Career Fellowship. This Fellowship is intended to assist those who are at a relatively early stage of their academic career to undertake a significant piece of publishable work.
Space microbiology
Dr Santomartino is based in the School’s Institute for Condensed Matter and Complex Systems. Her research in space microbiology focuses on the molecular mechanisms that drive microbial interaction with natural and artificial environments in space, to perform space biomanufacturing, recycling and in-situ resource utilization (ISRU), and to promote an efficient and sustainable impact of space exploration and its terrestrial applications.
She performed two microbiology experiments onboard the International Space Station, BioRock and BioAsteroid, launched in space in 2019 and 2020 respectively. Her work provided the first demonstrations of biomining on a space station, and raised considerable scientific interest, growing her reputation as an expert in the field. She is an invited scientific advisor in microbiology for the Italian Space Agency, and collaborates with international scientists for the creation of the NASA Decadel Survay on microbiology.
Fellowship
The Leverhulme Trust Early Career Fellowship will provide her the opportunity to establish a new interdisciplinary research direction in Edinburgh and worldwide, and to create a strong collaboration with the School of Biological Sciences.
The School welcomes applications from both external and internal scientists interested in applying for personal fellowships. In particular we have an internal deadline on 15 July 2021 for STFC Ernest Rutherford, Royal Society and EPSRC Fellowships.
We are keen to attract outstanding researchers from Edinburgh and across the world to join us as Postdoctoral Fellows. We offer a high quality research environment and support for you in your fellowship application process.
Fellowship opportunities
The School operates an internal review process for the following fellowship opportunities which have a deadline of Thursday 15 July 2021:
- STFC Ernest Rutherford Fellowships
- Royal Society University Research Fellowships
- EPSRC Open and Postdoctoral Fellowships
We also welcome applicants for other fellowships, the full list of which can be found on the weblink below.
Application information
Candidates are expected to have a PhD in Physics, Astronomy or a related discipline, and in most cases a few years research experience, as well as the ability to present clear evidence of their potential to undertake leading research.
The School of Physics and Astronomy is committed to advancing equality and diversity, welcoming applications from everyone irrespective of gender, ethnic group or nationality.
How to apply
Candidates must submit information including a research statement, CV and list of publications. Full application information can be found on the weblink below.
Astronomers have spotted a giant ‘blinking’ star, 100 times the size of the sun, towards the centre of the Milky Way.
Scientists observed that the enormous star, which lies 25,000 light years away, almost disappeared from the sky before slowly returning to its former brightness. Many stars in the Galaxy change in brightness because they pulsate or they are eclipsed by another orbiting star. However, it’s exceptionally rare for a star to become fainter over a period of several months and then brighten again, experts say.
Twinkle twinkle
Researchers believe the star, known as VVV-WIT-08, might belong to a new class of ‘blinking giant’ star system, where a huge star is eclipsed once every few decades by an as-yet unseen orbital companion.
The partner, which may be another star or planet, is surrounded by an opaque disc that covers the giant star, causing it to disappear and reappear in the sky.
As the blinking star is located in a dense region of the Milky Way, scientists considered whether an unknown dark object could have simply drifted in front of the giant star by chance. However, simulations showed that there would have to be an implausibly large number of dark bodies floating around the galaxy for this scenario to be likely.
Researchers from the University’s School of Astronomy and Physics collaborated on the discovery with experts from the University of Cambridge’s Institute of Astronomy, who led the study, the University of Hertfordshire, the University of Warsaw in Poland and Universidad Andres Bello in Chile.
VISTA telescope
VVV-WIT-08 was found by the Via Lactea survey (VVV) – a project using the British-built VISTA telescope in Chile and operated by the European Southern Observatory (ESO). ESO has been observing the same one billion stars for nearly a decade to search for those with varying brightness.
While VVV-WIT-08 was discovered using VVV data, the dimming of the star was observed by the Optical Gravitational Lensing Experiment, a long-running observation campaign run by the University of Warsaw.
Shining brightly
Edinburgh’s astronomers worked on the scientific modelling of the changes in the brightness of the star. Specifically they tried to understand the shape, opacity and velocity of the giant star’s orbital companion, through their analysis of the variations in VVV-WIT-08’s brightness. Scientists hope that future observations of VVV-WIT-08 in different parts of the electromagnetic spectrum may shed some light on the nature of this mysterious companion.
Dr Sergey Koposov, Co-author and Reader in Observational Astronomy, Institute for Astronomy, University of Edinburgh said:
The discovery of this rare star is very exciting, not only because the object itself is a bit of a mystery, but also because it tells us what discoveries can be made when we can access not only one single image of the sky, but when we’re able to observe its evolution with time. Essentially we are able to look at the movies of the sky as opposed to single photographs and this opens up a lot of opportunities for new discoveries.
Professor Philip Lucas, project co-leader, University of Hertfordshire reported:
Occasionally we find variable stars that don’t fit into any established category, which we call ‘what-is-this?’, or ‘WIT’ objects. We really don’t know how these blinking giants came to be. It’s exciting to see such discoveries from VVV after so many years planning and gathering the data.
Dr Leigh Smith, Project lead, University of Cambridge, Institute of Astronomy commented:
There now appear to be around half a dozen potential known star systems of this type, containing giant stars and large opaque discs. There are certainly more to be found, but the challenge now is in figuring out what the hidden companions are, and how they came to be surrounded by discs, despite orbiting so far from the giant star. In doing so, we might learn something new about how these kinds of systems evolve.
The study is published in Monthly Notices of the Royal Astronomical Society.
An extraordinarily precise measurement made by UK researchers using the Large Hadron Collider beauty (LHCb) experiment at CERN has provided the first evidence that charm mesons can change into their antiparticle and back again.
For more than 10 years, scientists knew that charm (D0, ‘D-zero’) mesons, subatomic particles that contain a quark and an antiquark, can travel as a mixture of their particle and antiparticle states, a phenomenon called mixing. However, this new result shows for the first time that they can oscillate between the two states.
In the strange world of quantum physics, the D0 meson can be itself and its antiparticle at once. This state, known as quantum superposition, results in two particles each with their own mass – a heavier and lighter version of the D0 particle. This superposition allows the D0 to oscillate into its antiparticle and back again.
The research, published today in Physical Review Letters, received funding from the Science and Technology Facilities Council (STFC), and involved colleagues from the Universities of Edinburgh, Oxford and Warwick.
Dr Mark Williams at the School of Physics and Astronomy’s Particle Physics Experiment research group, who convened the LHCb Charm Physics Group within which the research was performed, said:
Tiny measurements like this can tell you big things about the Universe that you didn’t expect.
Prof Franz Muheim from the School of Physics and Astronomy’s Particle Physics Experiment research group, who is chair of the LHCb Editorial Board and was internal reviewer of the paper said:
This observation of the mixing between neutral charmed meson is a further milestone in trying to elucidate the difference between the matter-antimatter asymmetry in the Universe.
Using data collected during the second run of the Large Hadron Collider, the researchers measured a difference in mass between the two particles of 0.00000000000000000000000000000000000001 grams – or in scientific notation 1x10-38g. This small mass difference leads to a very slow rate of oscillation: the time taken for one transition from particle to antiparticle and back is over 1000 times longer than the typical particle lifetime, making this a very rare process. It took all of the data collected by the LHCb experiment from 2015-2018 to make this discovery, along with a novel method to reduce experimental uncertainties.
There are only four types of particle in the Standard Model, the theory that explains particle physics, that can turn into their antiparticle. The mixing phenomenon was first observed in Strange (K0) mesons in the 1960s and in beauty (B) mesons in the 1980s. Until now, the only other particle that has been seen to oscillate is the strange-beauty (BS) meson, a measurement made in 2006.
This discovery of charm meson oscillation opens up a new and exciting phase of physics exploration; researchers now want to understand the oscillation process itself, potentially a major step forward in solving the mystery of matter-antimatter asymmetry. A key area to explore is whether the rate of particle-antiparticle transitions is the same as that of antiparticle-particle transitions, and specifically whether the transitions are influenced/caused by unknown particles not predicted by the Standard Model.
The result, 1x10-38g, crosses the ‘five sigma’ level of statistical significance that is required to claim a discovery in particle physics.
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Professor Catherine Heymans, a world-leading expert on the physics of the so-called dark universe, has been awarded the prestigious title, which dates back almost 200 years.
Heymans was recommended to the Queen for the role by an international panel, convened by the Royal Society of Edinburgh. She is Professor of Astrophysics at the University of Edinburgh and Director of the German Centre for Cosmological Lensing at Ruhr-University Bochum.
Her research seeks to shed light on the mysteries of dark energy and dark matter – elusive entities that together account for more than 95 per cent of the Universe.
Created in 1834, the position of Astronomer Royal for Scotland was originally held by the director of the Royal Observatory, Edinburgh. Since 1995, however, it has been awarded as an honorary title. The previous holder, Professor John C Brown, passed away in 2019.
As the eleventh Astronomer Royal for Scotland, Professor Heymans’ main focus will be on sharing her passion for astronomy with Scots from all walks of life. One of her first targets is to install telescopes at all of Scotland’s remote outdoor learning centres, which are visited by most of the country’s school pupils.
Professor Catherine Heymans, of the School of Physics and Astronomy, said:
I don’t think anyone forgets the first time they saw the rings of Saturn through a telescope, but too many people never have the chance. As Astronomer Royal for Scotland, I want to change that. My hope is that once that spark and connection with the Universe is made, children will carry that excitement home with them and develop a life-long passion for astronomy or, even better, science as a whole.
I am absolutely delighted to be named Astronomer Royal for Scotland and, as an advocate for equality and diversity, it is also a great honour to be the first woman appointed to the role. I will enthusiastically use this high-profile platform to advance amateur and professional astronomy within Scotland, and to promote Scotland internationally as a world-leading centre for science.
Professor Lord Martin Rees, the current UK Astronomer Royal, said:
It's excellent news that Professor Heymans has been appointed Astronomer Royal for Scotland. She is a distinguished successor to her predecessors in this role and I wish her a long and successful tenure.
Professor Dame Jocelyn Bell Burnell, President (interim) of the Royal Society of Edinburgh, said:
The Astronomer Royal for Scotland has always been a distinguished and respected astronomer, and Professor Heymans is exactly that. She will also always be distinguished as the first female to hold the position.
