News
- Radio signal reveals supernova origin 2023-05-17 Astronomers from the Oskar Klein Centre have revealed the origin of a thermonuclear supernova explosion thanks to the very first radio detection of the Type Ia-supernova.
- Hiranya Peiris appointed at Institute of Astronomy in Cambridge 2023-05-11 Congratulations to former OKC director Hiranya Peiris on her new appointment at the Institute of Astronomy in Cambridge!
- Physics and astronomy research in Stockholm in an interdisciplinary environment 2023-01-24 Since 2008, the Oskar Klein Centre has been attracting physics and astronomy researchers to Stockholm. Want to know more about what it is like to work in this interdisciplinary research environment?
- VR consolidator grant to Tim Linden 2022-12-02 The Swedish Research Council (Vetenskapsrådet) has awarded a consolidator grant of 10 million SEK to Tim Linden, assistant professor in Fysikum at Stockholm University. The project, “Shedding New Light on the Milky Way with TeV Electrons” will investigate the most extreme objects in our galaxy.
- Rare sighting of a luminous jet from a star-eating supermassive black hole 2022-11-30 Scientists have observed jets coming from a star being torn apart by a supermassive black hole. The observation has led to two independent publications in Nature and Nature Astronomy.
- IceCube finds evidence for neutrinos from a nearby galaxy 2022-11-08 Scientists have for the first time found evidence of high-energy neutrino emission from a nearby galaxy, NGC 1068. The results are a new step in the development of so-called multimessenger astrophysics, the study of the universe using many different types of information carriers, from light, to elementary particles, and gravitational waves.
- Twelve postdoctoral positions at the Oskar Klein Centre, Stockholm 2022-10-26 Positions involving instrumentation for axion experiments, particle physics & cosmology, gamma-ray bursts with Fermi, observational high-energy astrophysics, observational cosmology & LSST, fundamental physics using compact object mergers, multimessenger astrophysics with kilonovae, and first light galaxies and reionization with JWST & HST.
- Welcome to the new OKC Director 2022-10-26 After more than five years as OKC Director, Hiranya Peiris is stepping down. The OKC welcomes the new Director, Ariel Goobar.
- Massive Wolf-Rayet star observed exploding as a supernova 2022-06-22 This newly discovered type of stellar explosion – coined Type Icn – is described in the latest issue of the journal Nature.
- Tracing the cosmic web with supernovae 2022-03-22 A group of scientists, led by OKC PhD student Eleni Tsaprazi, have studied the environments in the large-scale structure where supernova explosions take place to explore whether supernovae can be used to map the high-redshift universe.
- Small black hole discovered outside the Milky Way 2022-01-25 An international team of astronomers, led by Dr. Sara Saracino of Liverpool John Moores University and including Dr. Christopher Usher of the Oskar Klein Centre, have discovered a small black hole outside of the Milky Way by studying how it influences the motion of a star in its close vicinity. This is the first time this technique has been used to detect a black hole outside of our own galaxy.
- Radio Flashes Could Lead the Way to Detection of Dark Matter 2022-01-12 The majority of matter in the Universe is cold and dark and has yet to be directly observed. One candidate for this dark material is the axion, a hypothetical elementary particle.
- Postdoc Interviews: Khyati Malhan 2021-12-15 Khyati has been with the OKC for a couple of years now and will be moving to Germany to start a Humboldt Fellowship in the autumn. He works in the field of Milky Way formation and dynamics and uses stellar dynamics to understand the formation and dynamics of our Galaxy, and also to examine the nature of dark matter.
- Two OKC researchers will be among the first to use JWST 2021-10-13 Both Angela Adamo and Emil Rivera-Thorsen from the SU Astronomy department had proposals chosen from the more than 1000 that were submitted asking for time in the first cycle of telescope operations.
- Astronomers find galaxy revealing its innermost secrets – in 12 copies 2021-07-03 An international group of astronomers, led by Thøger Emil Rivera-Thorsen from the Oskar Klein Centre, have found a distant galaxy which has a rarely seen hole in its interstellar gas, allowing a direct view to the hot, massive stars at its very center. Luckily this galaxy is lensed by a foreground galaxy cluster and the resulting 12 images of the original galaxy can be studied in great detail.
- The most energetic transient events : supernovae or stars disrupted by black holes? 2021-07-03 A new type of energetic transient has been discovered in the center of active galaxies. There are two potential causes for these events : the explosion of a massive star or the tidal disruption of a star by the galaxy's central, supermassive black hole.
- Quest for the unknown elementary particle 2021-07-03 Thanks to a 35.2 million SEK grant from the Knut and Alice Wallenberg Foundation, Sara Strandberg and her colleagues can go on the hunt for new particles that could explain the mass of the Higgs boson
- GD-1 Stellar Stream and Dark Matter in Our Milky Way 2021-07-03 Streams of stars orbiting in the halo of our Milky Way Galaxy can be used to constrain the shape of our Galaxy's dark matter halo and the amount of mass inside the radius of our Sun's orbit.
- OKC researchers will use Wallenberg grant to study light from merging neutron stars 2021-07-03 The era of multi-messenger astrophysics has just begun and recently a merging neutron star system has been detected in gravitational waves and subsequently electromagnetically. This grant supports a concentrated research effort across groups at the OKC to study future neutron star merger events from their detection, through simulations and modeling and extending to their electromagnetic follow-up and the use of these events to measure the expansion rate of our Universe.
- NASA’s Fermi Mission Reveals its Highest-energy Gamma-ray Bursts 2021-07-03 Gamma-ray bursts are the most powerful explosions known in the Universe, yet we still don’t understand the physics behind their high-energy radiation. An international team, partly led by OKC researcher Magnus Axelsson, has studied nearly 200 events observed over 10 years, the largest sample collected at these energies thus far. The study reveals many new observational findings, it also tells us that there is still a lot we don’t know.
- The Zwicky Transient Facility sees “first light”: a new era in the study of the dynamic sky 2021-07-02 The Zwicky Transient Facility is now ready to start operations. A new robotic camera with the ability to capture hundreds of thousands of galaxies in a single shot has taken its first image of the sky. The recently installed camera is part of a new automated sky-survey project based at the Palomar Observatory in California and a revolutionising tool for the study of rapidly varying cosmic phenomena
- The cosmoparticle exchange programme 2021-07-02 Welcome to the Cosmoparticle Visitor Exchange Programme, linking London UCL, Ohio CCAPP, New York CCA, Stanford KIPAC, Stockholm OKC and Durham ICC.
- ERC Grant to detect the existence of axions 2021-07-02 Frank Wilczek, professor at the Department of Physics at Stockholm University, has been awarded the ERC Advanced Grant for the theoretical study of axions. Axions are hypothetical particles whose existence would solve the dark matter problem.
- A successful public event for OKC@10 2021-07-02 On Sept 11 the OKC organized a public science event for the Stockholm community. It was held at the Royal College of Music and included a student jazz ensemble, a talk on dark matter by Dr. Katherine Freese and a discussion between Dr. Freese and Dr. Sean Carroll.
- First test of the interaction of dark matter with pions 2021-07-02 Over 80% of the matter content of the universe is made of dark matter. In order to unravel its nature, direct-detection experiments look for the scattering of dark matter particles off atomic nuclei.
- Wallenberg Project Grant to OKC Director Hiranya Peiris 2021-07-02 The Knut and Alice Wallenberg Foundation have awarded a project grant of 37.8 million crowns over five years to OKC Director Hiranya Peiris for the project Understanding the Dynamic Universe
- Dark Matter Is Not "Fuzzy" 2021-06-08 New research published in Physical Review Letters by former OKC Fellow Keir Rogers and OKC Director Hiranya Peiris rules out one of the more popular and well-motivated dark matter candidates.
- Did a spaghettified star close to a supermassive black hole send out a high-energy neutrino? 2021-06-04 In a new article in Nature Astronomy researchers at the Oskar Klein Centre participate in a study that connects an energetic ghost-particle trapped in the Antarctic ice with a shredded star in a distant galaxy.
- Echoes from the infant universe 2021-04-14 Developing metamaterial absorber technologies for the upcoming LiteBIRD satellite with support from the Swedish Space Agency.
- Seeing neutron-star collisions with multiple glasses 2021-02-23 Neutron stars are among the densest objects in our Universe, with “Sun-like” masses but “city-size” radii. When two of these extremely dense objects collide, they give rise to a cataclysmic event that is so powerful that it can be observed at very large distances. In August 2017, the collision of two neutron stars a trillion billion (1 followed by 21 zeros) kilometers away from Earth was detected as a gravitational wave signal and across the full electromagnetic spectrum as well. This simultaneous detection provided an unprecedented opportunity to address long-standing, fundamental, questions in (astro)physics, including the origin of some heavy elements like gold and platinum, properties of matter at densities exceeding those inside atomic nuclei and the expansion rate of our Universe.
- Simons Observatory telescope construction making good progress 2021-01-14 Researchers at the Oskar Klein Centre and Stockholm University are leading the optical modeling efforts for a new ground-based telescope called the Simons Observatory.
- Cosmic Conundra 2020-12-07 Former OKC postdoc Florian Kühnel discusses his recent paper on primordial black holes and gravitational waves.
- Hunting for Gravitational Wave Counterparts 2020-12-07 Since the groundbreaking first detection of merging neutron stars in gravitational waves and electromagnetic radiation in August 2017, researchers at Stockholm University have continued to search for electromagnetic counterparts – bright transient sources in the sky – in connection with gravitational-wave events.
- OKC named one of top three Linnaeus Excellence Centres in Natural Sciences 2020-10-13 In 2005, the Swedish government commissioned the development of Centres of Excellence, known as Linnaeus Centres, in order to build strong research environments and improve the international competitiveness of Swedish research. This programme has now been evaluated by an international panel; the results were presented at a conference in Stockholm in March.
- Gravitational waves can show when the core of a dying star breaks down into free quarks 2020-10-05 Astronomers have known for a long time that during the death of a massive star gravity causes the core to collapse and then rebound with a bounce into an explosion. Such core-collapse supernovae are some of the most energetic explosions in the Universe. However, we know little about what is happening in the cores of these objects during this process because light cannot escape them.
- XENON1T sees an excess of electron recoil events 2020-09-25 Underneath a mountain in Italy sits 3.2 tonnes of liquid xenon waiting patiently for (among other things) a dark matter candidate particle to recoil off one of the xenon nuclei. And, although this nuclear recoil event has yet to be observed, researchers working on this experiment report that they see more than they expect of something else -- electron recoil events.
- Sunny Vagnozzi wins Springer Thesis Award 2020-03-20 Dr. Vagnozzi, who was a PhD student in the Oskar Klein Centre, defended in 2019 and will have his thesis published in the Springer Theses series.
- Possible hint of a dust-enshrouded neutron star in SN 1987A 2020-01-24 In February of 1987 a blue supergiant star in the Large Magellanic Cloud exploded. The Large Magellanic Cloud is a satellite dwarf galaxy of our own Milky Way and this event, called SN 1987A, continues to be the closest observed supernova in more than four centuries.
- New VR research environment grant will focus on axions 2020-01-20 The Oskar Klein Centre and Stockholm University will become a hub for axion research beginning now in 2020 thanks to a new Research Environment grant from the Swedish Research Council. A theoretical particle so far, the axion was introduced to explain why the strong force works the same both backwards and forwards in time and is also considered a serious dark matter candidate. The discovery of a cosmic axion background, or the ability to rule it out, would be an important result for both Standard Model physics and dark matter searches.
- The extreme of rarity 2019-04-30 OKC researchers helped reveal the rarest nuclear reaction now known to mankind. To observe this ultra-rare process, XENON1T watched a tonne of ultra-pure liquid xenon for a year. The experiment was featured on the cover of the scientific journal 'Nature'
- Merging neutron stars detected in gravitation waves and electromagnetic radiation 2019-02-13 Gravitational waves from the merger of two neutron stars have been detected for the first time. Scientists around the world pinpointed the source to a galaxy 130 million light years away.
- OKC researchers secure HST time in Cycle 26 2018-11-13 Angela Adamo and Matthew Hayes both had successful medium HST proposals in Cycle 26, the most oversubscribed cycle in the history of HST. Angela's observations will explore how dense, young clusters of stars interact with their surroundings. Matthew's observations will look for gas that is thought to envelope galaxies and fuel their future generations of stars.
- Wimpy supernova may signal the birth of a double neutron star system 2018-11-13 The star that died in the supernova likely left behind a binary neutron star system. These dense stellar remnants will ultimately merge with each other, giving off gravitational and electromagnetic waves.
- The future of neutrino physics is bright with the construction of Hyper-Kamiokande 2018-09-28 A large collaboration of scientists will build a new neutrino detector, known as Hyper-Kamiokande, in Japan. Construction will begin in 2020 and the completed instrument will explore neutrinos from supernovae as well as other unsolved problems in particle physics.
- The world's largest dark matter detector, XENON1T, reaches a new level of sensitivity 2018-09-14 The international collaboration, XENON, which includes members of Stockholm University has built the world's most sensitive detector for dark matter. After one year of data collection, the experiment has reached a greater sensitivity than ever before.
- Massive star explodes in metal-poor galaxy 2018-05-09 This week's issue of Nature Astronomy tells the story of a massive and metal-poor star that exploded as a supernova. It is located in a distant faint galaxy and the authors suggest that it is the low metal content of the host galaxy that allows such a massive star to explode.
- Sara Strandberg Wins the Göran Gustafsson Prize 2018-04-17 The prize is given to Dr. Strandberg for her research in experimental particle physics and and its potential connection to dark matter.
- A strange stellar explosion with enduring brightness 2017-11-15 Located in a dwarf galaxy 500 million light years away, supernova iPTF14hls initially seemed like an ordinary explosion of a red giant star. Then it lasted more than four times longer than a normal supernova.