The Sloan Digital Sky Survey (SDSS) have released a comprehensive analysis of the largest three-dimensional galaxy map of the Universe ever created, filling in the most significant gaps in our exploration of its history over 11 billion years of cosmic time.
The new results are detailed measurements of more than two million galaxies and quasars, derived from a subset of the SDSS: the extended Baryon Oscillation Spectroscopic Survey (eBOSS), which involved an international collaboration of more than 100 astrophysicists.
The detailed analysis of this dataset is described in more that 20 technical papers which the eBOSS team have made public. These papers, more than 500 pages in total, mark the completion of the key goals of the survey. Within the eBOSS team, individual groups at universities around the world focused on different aspects of the analysis. To create the part of the map dating back six billion years, the team used luminous red galaxies. Farther out, they used younger blue galaxies. Finally, to map the Universe eleven billion years in the past and more, they used quasars, which are bright galaxies lit up by material falling onto a central supermassive black hole. Each of these samples required careful analysis in order to remove contaminants and reveal the patterns of the Universe.
The team from the Institute of Astronomy at the School of Physics and Astronomy, including Dr Shadab Alam and Prof John Peacock, led an analysis focused on understanding the young blue galaxies. There is a long-standing question of nature vs nurture when one looks at the populations of different types of galaxies. More precisely, what aspects of the galaxy properties are affected by the local conditions around these galaxies? Such questions are interesting in their own right, but they are also particularly important to make sure our measurements of the properties of the Universe are not biased by local conditions of these galaxies.
The wealth of data released by the eBOSS team will continue to be one of richest datasets for astronomers to attack some of the most challenging questions in astrophysics.
The effort from the University of Edinburgh was supported by the European Research Council through the COSFORM Research Grant.
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Scientists adjust the Remote3 project in order that children can learn and develop coding and technological skills during lockdown.
Remote3 was designed to help students from remote schools in the Scottish Highlands and Islands access exciting science, technology, engineering and maths (STEM) challenges. Since lockdown, the project has been adapted to continue online. Children all over the country have been attending weekly webinars that introduce a coding challenge and provide information about the uses of robots around the world.
Students have created code during weekly tasks which have become increasingly challenging. They have then had the chance to test their code remotely on a LEGO Mindstorm robot, submitting their work in advance, which is then tested live in the webinar. Experienced computer scientists, physicists and technicians have been on hand to answer students’ questions about coding, robots and science during the sessions.
Eight weeks on, the students have developed their skills to tackle the final summer challenge: a two-month project which will involve designing a planetary surface for their robot rovers to explore, as well as creating the code required to successfully explore it. At the end of the project in September, students will get the chance to test their completed code and celebrate their achievements in a final online event.
The Remote3 team combines School of Physics and Astronomy particle physicists Dr Xin Ran Liu and Prof. Alex Murphy, with the Boulby Underground Laboratory and Science and Technology Facilities Council (STFC) Public Engagement teams, along with support from STFC’s Scientific Computing Department. The project was funded by the STFC Spark Award programme.
Xin reported:
We want the project to inspire innovation and creative design, develop digital skills, encourage teamwork, team-building and oral and written presentation skills in a diverse environment, as well as provide awareness of the remarkable ongoing front-line scientific activity taking place across the UK and overseas. In doing so we want to encourage the next generation of young people into a career in STEM subjects.
Remote3 originally aimed to give Scottish school children the chance to build and control LEGO rovers remotely more than one kilometre underground in the Boulby Underground Laboratory. The Boulby Underground Laboratory, on the edge of the North York Moors, is home to a Mars Yard, where students’ rovers will eventually be tested when the schools project can take place. The rovers will be following in the tracks of full-size Mars Rover prototypes, which have been tested there as part of international space research events in the past. The extremely salty, hot and dusty environment there simulates conditions found on other planets and will add to the challenge of the competition. The project is planned to run for at least two years, engaging with hundreds of students.
Scientists investigate the effects of microbes on asteroidal material in space under microgravity conditions.
BioAsteroid, a space biomining experiment, uses a collection of 12 automatic culturing devices fitted with a layer of material on which bacteria and fungus will be grown. The project will investigate the growth of the bacteria and fungus on asteroidal material in microgravity, studying biofilm formation, bioleaching and other chemical and biological changes in microgravity, including the genetic transcriptional changes in space.
This follows an earlier experiment investigating the formation of biofilms on natural surfaces and the bioleaching of elements from basaltic rock, BioRock. This experimental apparatus, which flew to the space station in 2019 with SpaceX, is a miniature bioreactor, and allowed the scientists to study how microbes grow in space and what effect microgravity has on their growth.
BioAsteroid scientists will be flying their second experiment to the International Space Station in November this year.
The UK Centre for Astrobiology, which involves a number of School of Physics and Astronomy researchers, and Kayser Space have collaborated on the project, which is the first European experiment to be fast-tracked to the International Space Station through the Bioreactor Express programme.
Prof. Charles Cockell, School of Physics and Astronomy, said:
By studying biofilm formation of these organisms on the asteroidal material in microgravity, BioAsteroid will investigate how space conditions ultimately affect microbe-mineral interactions, addressing questions on the biochemistry of the organisms, biofilm morphology and structure, fungal attachment and the ability of the microbes to break down rock, a key process for the future use of microorganisms in space exploration, including the mining of asteroids.
Dr. Rosa Santomartino, School of Physics and Astronomy, said:
Microorganisms perform many useful tasks on Earth, and they will be essential for human space exploration. With BioRock first and BioAsteroid now, we are investigating this possibility and advancing our knowledge on microbial response to space conditions, with benefits for both space and terrestrial bioindustry.
The Science Verification Test for BioAsteroid will take place later this month in Edinburgh, where the microbes will be grown for the first time on the actual flight culturing hardware. The experiment is scheduled to be launched to the International Space Station with SpaceX in November 2020.
The School welcomes applications from both external and internal scientists interested in applying for personal 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:
- UKRI Future Leaders Fellowships
- Royal Society University Research Fellowships
- STFC Ernest Rutherford Fellowships
- EPSRC Fellowships
- Royal Astronomical Society Fellowships
- Marie Sklodowska-Curie Individual Fellowship
- Dorothy Hodgkin Fellowship
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. We particularly encourage applications from female and/or BAME candidates.
How to apply
Candidates must submit information including a research statement, CV and list of publications. The deadline for a number of these fellowships is noon, 17 July 2020.
Astronomers have seen what could be the first ever light flare detected from a black hole merger.
Their findings potentially create a new chapter within astrophysics because the merger of black holes was not expected to generate light waves, as the gravity associated with black holes is so great that nothing – not even light – usually escapes from them.
The study – published in Physical Review Letters – involved an international team of scientists, including physicists from the School of Physics and Astronomy.
Gravitational waves
Previous observations have shown that when two black holes spiral around each other and ultimately collide and merge, they generate ripples in space and time known as gravitational waves.
The phenomena is a direct consequence of Einstein’s theory of gravity and was first detected by scientists in 2015, leading to the Nobel Prize in Physics.
Black hole merger
In the latest study, a black hole merger was spotted by the National Science Foundation’s Laser Interferometer Gravitational-wave Observatory (LIGO) and the European Virgo detector in May 2019. As the black holes collided with each other, they sent out the expected gravitational waves.
Shortly after, the California Institute of Technology’s (Caltech) Zwicky Transient Facility (ZTF), located at the Palomar Observatory near San Diego, captured a flare of light that was pinpointed to the same area as the gravitational wave event.
This supermassive black hole was burbling along for years before this more abrupt flare. The flare occurred on the right timescale, and in the right location, to be coincident with the gravitational-wave event. In our study, we conclude that the flare is likely the result of a black hole merger, but we cannot completely rule out other possibilities.
Matthew Graham - Lead author, Research Professor of Astronomy, Caltech
Light flare
Supermassive black holes lurk at the centre of most galaxies, including our own, the Milky Way. These central supermassive black holes can be surrounded by a disc of flowing gas which contains swarms of stars and smaller black holes.
The flow of the gas helps to bring the smaller black holes together, enabling them to merge, and creates a larger black hole within the disk. Upon creation, the new black hole has a large velocity and it is given what scientists described as “a kick” through the gas disk.
Experts said it is the reaction of the gas to the new speeding black hole that creates a bright light flare, visible with telescopes.
The newly formed larger black hole should cause another burst of light in the next few years, according to the scientists.
This result, the optical flash resulting from two black holes colliding and crushing the gas around them, is so exciting. As a wee kid, I was hooked by the idea of black holes and now, as a big kid, the fact that we have ‘seen’ as well as ‘heard’ these black hole mergers, is an amazing discovery that has deep implications for astrophysics. I'd like to thank the LIGO, Virgo and ZTF collaborations for their dedication and hard work over the years and I hope this finding inspires people of all ages and informs future studies in astronomy.
Dr Nicholas Ross - Project collaborator and STFC Ernest Rutherford Fellow at the Institute for Astronomy, University of Edinburgh.
The paper, titled, "A Candidate Electromagnetic Counterpart to the Binary Black Hole Merger Gravitational Wave Event GW190521g” was funded by the NSF, NASA, the Heising-Simons Foundation, and the GROWTH (Global Relay of Observatories Watching Transients Happen) programme.
The School is committed to addressing equality, diversity and inclusion, and has a zero-tolerance stance to any form of racist or discriminatory behaviour.
As Head of School, I want to share with you the following message that has been written in collaboration with members of the School’s Equality, Diversity and Inclusion (EDI) Committee.
Race relations worldwide have been brought into sharp focus by the recent brutal killing of George Floyd in the USA. The harmful and toxic effects of discrimination are obviously not unique to the USA; at this time many of us will be reflecting on experiences of racism closer to home - be that personal experiences or those of our friends, family and loved ones, as well as those of colleagues, students, and others in our community. The events of recent days will also have generated feelings of anger, distress, or anxiety amongst us.
The University has recorded its outrage at the killing of George Floyd and has recognised in its published statement our collective responsibility to address systemic racism and to treat each other with dignity, compassion and respect.
My message is one of compassion for anyone who has been a target of racism and those that are affected by the current protests. I stand firmly behind our School’s commitment to equality, diversity and inclusion, and a zero-tolerance stance to any form of racist or discriminatory behaviour. The School of Physics & Astronomy embraces the power that diversity brings. Our Juno / Athena SWAN plan includes institutional support for a network for staff who identify as BAME, and last summer the School employed a summer intern to co-develop the School's EDI website, including links to resources on race. However, it is clear there is much more to be achieved in improving the representation and experiences of Black, Asian and minority ethnic staff and students in our School.
In recent months, the senior management team of the College of Science & Engineering has been discussing these issues. All members of this team, including all Heads of Schools, have committed to take part in bespoke Race Equality training, including addressing white privilege and recruitment/promotion. We have also committed to have open conversations about race, racism and science, and the College has agreed to fund Diversity Challenge, a live event that highlights the under-representation of certain groups in academia.
Over the summer, the School is employing student interns to look at the visible representation of scientists in JCMB and to look at aspects of decolonising the physics and astronomy we teach.
Before the lockdown, the School's EDI Committee had been looking at ways to better address the issues faced by BAME staff & students, and other protected groups. If you wish to be part of our School’s ongoing efforts to address these challenges, please contribute to the work of our EDI Committee (including, if appropriate, suggesting additional resources for the School's EDI website). In the first instance, please get in touch with the Director of EDI, victoria.martin [at] ed.ac.uk (Prof Victoria Martin).
I am a member of the EDI Committee and we are here to support any member of the School community affected by racism or by the recent events in the USA and the UK. If you would like to talk to anyone in confidence, please again contact our victoria.martin [at] ed.ac.uk (Director of EDI).
Best wishes, and stay safe.
Prof Jim Dunlop
New precision measurements of the lineshape of the χc1(3872) are helping scientists to understand the nature of this puzzling meson.
Studies of hadron states allow us to understand the properties of the strong nuclear force that binds quarks together. Since its discovery in 2003 by the Belle collaboration there has been much speculation about the nature of the χc1(3872) state. Its properties are not consistent with it being a conventional charmonium state composed of a charm-anticharm pair. This has led to speculation that it is more exotic in nature, e.g. that is a four-quark state (tetraquark) or a bound DD* molecular state. Following the discovery of the χc1(3872) state there has been a resurgence in exotic spectroscopy and many new particles (the ‘XYZ’ states) have been reported.
The LHCb (Large Hardron Collider beauty experiment) collaboration has just released the results of two analyses that make precision studies of the χc1(3872) lineshape using its decay to the J/ψπ+π− final state. Two models were used to study the χc1(3872) lineshape (Breit−Wigner and Flatté). For the first time a non-zero value of the natural width of this state is found. In addition, the precision on the measurement of the mass is improved by more than a factor of two. The difference of the χc1(3872) mass to the sum of the D and D* meson masses is found to be only 70±120 keV. The lineshape measurements hint towards the conclusion that the χc1(3872) has both charm-anticharm and molecular.
Dr Matthew Needham, Reader at the University of Edinburgh, who led one of the two studies commented:
These studies are really groundbreaking in terms of the achieved precision. The puzzle of the nature the χc1(3872) remains but these results will help us to piece together the puzzle. We are continuing to work on this subject and more results are expected in the future.
In particular it is planned to build on the Flatté fit model to make the first coupled channel analysis of the χc1(3872) lineshape in the J/ψπ+π− and DD* decay modes. In addition, the LHCb detector is currently being upgraded allowing an order of magnitude more data to be collected when the LHC restarts running in 2021.
Discovery that helium and ammonia can form compounds over a wide pressure range.
Helium and ammonia are both found in large quantities inside icy giant planets. Because helium is generally considered to be the most inert element in the periodic table, it is not clear whether these two components can react with each other under planetary conditions of extreme pressures and temperatures, or what kinds of states might emerge.
Using crystal structure search techniques and ab initio molecular dynamics simulations, an international team including Dr Andreas Hermann from the Centre for Science at Extreme Conditions found that helium-ammonia compounds can form over a wide pressure range.
Upon heating, these compounds are predicted to form plastic phases (with spinning molecules on periodic lattices) and superionic states (which are part liquid, part solid). The study published in Physical Review X and featured in American Physical Society review Physics, provides new and surprising insights into the properties of compounds that may exist in icy giant planets and into new chemistry and physics of helium compounds under extreme conditions.
Congratulations to Dr James Aird and Dr Maxwell T. Hansen who have been awarded UK Research and Innovation (UKRI) Future Leaders Fellowships.
The UKRI Future Leaders Fellowships have been instigated to ensure the strong supply of talented individuals needed for a vibrant environment for research and innovation in the UK. In this third round of the Fellowships, we are pleased that two successful candidates have chosen the School of Physics and Astronomy as their new home.
Galaxy evolution, and challenging the Standard Model
Dr James Aird will be joining the Institute for Astronomy. He will use his Future Leaders Fellowship to probe the lifecycles of supermassive black holes on timescales of millions to billions of years, and thus determine their impact on the growth and evolution of the galaxies they lie in. To achieve this, he will develop new statistical tools to combine data from a range of new, large astronomical surveys spanning X-ray, optical and radio wavelengths.
Dr Max Hansen, who will be joining the Institute for Particle and Nuclear Physics, is a theorist seeking evidence for phenomena that go beyond the current paradigm of particle physics, the Standard Model. Specifically, he is focused on understanding the role of the strong force in uncovering new physics signatures. He will use his Future Leaders Fellowship to combine cutting-edge high-performance computing with an advanced theoretical framework to inform experiments challenging the Standard Model, such as those being performed at CERN’s Large Hadron Collider.
These Fellowships follow Anna Lisa Varri and Franz Herzog who were successful in the first two rounds of the award.
UK Research and Innovation Future Leaders Fellowship
The scheme will help the next generation of researchers, tech entrepreneurs, business leaders and innovators across different sectors and disciplines to get the support they need to develop their careers. Awardees will each receive between £400,000 and £1.5 million over an initial four years, supporting novel projects, equipment and personal development.
A supernova which is at least twice as bright and energetic, and likely much more massive than any yet recorded, has been identified by a team of astronomers.
Scientists believe the supernova, dubbed SN2016aps, could be an example of an extremely rare ‘pulsational pair-instability’ supernova, possibly formed from two massive stars that merged before the explosion. The findings are published in Nature Astronomy.
Such an event so far only exists in theory and has never been confirmed through astronomical observations.
The team international team of astronomers who identified the supernova include Dr Matt Nicholl, former Royal Astronomical Society fellow and current long-term visitor at the Institute of Astronomy, the University of Edinburgh, and lecturer at the University of Birmingham, as well as astronomers from Harvard, Northwestern University and Ohio University.
Supernovae can be measured using two scales – the total energy of the explosion, and the amount of that energy that is emitted as observable light, or radiation. In a typical supernova, the radiation is less than 1 per cent of the total energy. However, in SN2016aps, the team found the radiation was five times the explosion energy of a normal-sized supernova. This is the most light ever seen emitted by a supernova.
In order to become this bright, the explosion must have been much more energetic than usual. By examining the light spectrum, the team were able to show that the explosion was powered by a collision between the supernova and a massive shell of gas, shed by the star in the years before it exploded.
The team observed the explosion for two years, until it faded to 1 per cent of its peak brightness. Using these measurements, they calculated the mass of the supernova was between 50 to 100 times greater than our sun (solar masses). Typically supernovae have masses of between 8 and 15 solar masses.
Supernova 2016aps was first detected in data from the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), a large-scale astronomical survey programme. The team also used data from the Hubble Space Telescope, the Keck and Gemini Observatories, in Hawaii, and the MDM and MMT Observatories in Arizona. Other collaborating institutions included Stockholm University, Copenhagen University, California Institute of Technology, and Space Telescope Science Institute.
The research was funded through a Royal Astronomical Society Research Fellowship, along with grants from the National Science Foundation, NASA and the Horizon 2020 European Union.