Astroparticle Physics
Articles tagged with Astroparticle Physics
Ultrahigh-energy cosmic messengers may carry ultraheavy secrets
The DAMPE satellite sheds light on the origin of cosmic rays
The DAMPE satellite has identified a universal feature in the energy spectra of primary cosmic ray nuclei, revealing that spectral softening occurs around a rigidity of about 15 TV. This observation strongly supports models explaining the acceleration and transport of cosmic rays based on their rigidity.
Neutrinos caught on camera
A new detector technology has been developed to track elementary particles in large volumes of unsegmented scintillator material. The system uses a plenoptic camera and single-photon avalanche diode array sensors to achieve high-resolution 3D tracking, even in photon-starved conditions.
A student-led experiment sets new limits in the search for axions
A team of undergraduate students built a cavity detector to search for axions and set new experimental limits on their properties. The result was achieved with relatively limited resources, showcasing the potential for small-scale experiments in precision cosmology.
What if dark matter came in two states?
Researchers suggest that dark matter may consist of multiple particles, whose behavior varies depending on the cosmic environment. This could explain why a signal observed at the center of our galaxy is not seen in dwarf galaxies.
The ultra-high-energy neutrino may have begun its journey in blazars
A new study suggests that the ultra-high-energy neutrino may have originated from a population of blazars, which could provide a plausible explanation for the rare phenomenon. The researchers used a combination of simulations and observations from various instruments to test their hypothesis.
Scientists establish a means of using lasers to increase muon lifetime
Researchers at the University of Plymouth have discovered a method to increase muon lifetime using intense laser pulses. By applying quantum interference principles, they aim to develop new scientific facilities that utilize muons instead of electrons.
Astronomers reveal new details about dark matter’s influence on Universe
Researchers created the highest resolution map of dark matter, showing its interaction with normal matter through gravity. The new data from NASA's James Webb Space Telescope confirms previous research and provides new details about dark matter's influence on the Universe.
Groundbreaking mapping: how many ghost particles all the Milky Way’s stars send towards Earth
A new study has created a comprehensive model of neutrino mapping, revealing that most stars in the Milky Way generate and emit these ghost particles. The research provides valuable insights into the universe, offering a unique way to explore cosmic phenomena.
The leaking star cluster
Astronomers have detected a new gamma-ray source near Westerlund 1, a young massive star cluster in the Milky Way. The source is connected to a 'nascent outflow' of particles driven by the cluster's collective wind, creating a cavity in the interstellar medium.
KATRIN tightens the net around the elusive sterile neutrino
The KATRIN collaboration presents the most precise direct search for sterile neutrinos through measurements of tritium β-decay. No sign of a sterile neutrino was found, excluding a large region of parameter space suggested by earlier anomalies. The result relies on distinct detection methods and complements oscillation experiments.
After nearly 100 years, scientists may have detected dark matter
Researchers believe they have finally detected gamma rays predicted by the annihilation of theoretical dark matter particles. The observed energy spectrum matches the emission predicted from weakly interacting massive particles, with a mass approximately 500 times that of a proton.
Our solar system is moving faster than expected
A study from Bielefeld University reveals that the solar system is moving more than three times faster than predicted by current models. This deviation was detected using data from radio galaxies, which emit strong radio waves and can penetrate dust and gas.
Neutrinos ‘flavor’ may hold clues to the universe’s biggest secrets
Physicists have analyzed how neutrinos change 'flavor' as they travel through the cosmos, gaining insights into their masses and evolution. The study's findings hint at possible Charge-Parity violation in neutrinos and their antimatter counterparts, with researchers seeking more data to answer fundamental questions about the universe.
Astronomy breakthrough: The mystery of dark matter can be unraveled using radio telescopes
Researchers from Tel Aviv University predict that detecting radio waves from the cosmic dark ages can help resolve the nature of dark matter. The study uses computer simulations to show that dense clumps of dark matter formed throughout the Universe, pulling in hydrogen gas and causing it to emit intense radio waves.
Galaxies reveal hidden maps of dark matter in the early universe
Researchers at Rutgers University uncovered evidence of how galaxies expand by tracing the invisible scaffolding of the universe created by dark matter. They analyzed large samples of special galaxies called Lyman-alpha emitters to study galaxy formation and evolution over billions of years.
Could a primordial black hole’s last burst explain a mysteriously energetic neutrino?
Recent detection of a record-setting neutrino may be the first evidence of Hawking radiation from a primordial black hole. If confirmed, it would indicate that PBHs make up most of dark matter in the universe.
Astronomers discover rare Einstein cross with fifth image, revealing hidden dark matter
Scientists have discovered a rare cosmic pattern known as an Einstein Cross with a fifth image, which reveals hidden dark matter. The team used computer modeling and analysis to infer the presence of a massive, invisible mass surrounding the foreground galaxies.
Faster energetic particles arriving later
Researchers analyzed 10 SEP events with inverse velocity dispersion signatures to investigate underlying mechanisms. The study found that energy-dependent release and longer timescales for high-energy particles explain the counterintuitive behavior.
Using exoplanets to study dark matter
Researchers propose that Jupiter-sized exoplanets may accumulate and collapse into detectable black holes due to dark matter. This process could potentially generate multiple black holes in a single exoplanet's lifetime, making exoplanet surveys a promising method for hunting superheavy dark matter particles.
Intergalactic experiment: Researchers hunt for mysterious dark matter particle with clever new trick
Physicists from the University of Copenhagen have discovered a step-like signature that resembles the signature of an elusive axion particle using galaxy clusters. This method has greatly increased what we know about axions, allowing researchers to narrow down the space where it can be found.
CTAO LST collaboration paper provides new clues about gamma-ray burst jets
The CTAO LST Collaboration presents groundbreaking findings on the nature of gamma-ray bursts, supporting theoretical models of structured, multi-layered jets. The observations of GRB 221009A provide new clues about jet formation mechanisms and the central engine behind these cosmic phenomena.
Astronomical breakthrough reveals star that survived destructive encounter with black hole
Researchers observed a flare caused by a star falling onto a black hole and surviving the encounter. The discovery suggests that these flares may be part of a longer, more complex story about supermassive black holes.
Scientific breakthrough uses cold atoms to unlock cosmic mysteries
Researchers successfully demonstrate Fermi acceleration mechanism with ultracold atoms, unlocking new understanding of cosmic rays behavior. The technology has the potential for high-precision control over particle acceleration and opens new possibilities for investigating phenomena relevant to high-energy astrophysics.
Can the Large Hadron Collider snap string theory?
Researchers from Penn University propose a five-member particle package, known as the 5-plet, that string theory cannot accommodate. This particle family is absent in any known string-based calculation, raising concerns about the framework's validity.
Rice researchers search for ultralight dark matter using a magnetically levitated particle
Researchers at Rice University have conducted the first direct search for ultralight dark matter using a magnetically levitated particle. Despite high sensitivity, they did not find evidence of the anticipated signal, ruling out specific interactions between dark matter and ordinary matter.
Unravelling the origin of mysterious radiation
A team from Norwegian University of Science and Technology proposes that supermassive black hole winds accelerate particles to create the mysterious high-energy radiation. The winds, which can reach speeds of up to half the speed of light, may be responsible for the creation of ultra-high-energy cosmic rays.
UTA ATLAS team shares Breakthrough Prize in physics
The University of Texas at Arlington's ATLAS Experiment team has made significant contributions to the discovery of the Higgs boson particle. The team's work on the Large Hadron Collider at CERN led to a Noble Prize in 2013 and has earned them a $1 million Breakthrough Prize in Fundamental Physics.
Dark matter formed when fast particles slowed down and got heavy, new theory says
Researchers at Dartmouth College propose a new theory on the origin of dark matter, suggesting it could have formed from high-energy massless particles that rapidly condensed into cold, heavy particles. The theory can be tested using existing observational data, including the Cosmic Microwave Background radiation.
Advanced digital detector array enhances charged-particle decay studies
Researchers developed an advanced detector system combining silicon and germanium detectors for high-efficiency charged-particle decay studies. The system achieved precise tracking of decay processes and efficient discrimination between particles, showcasing its potential for studying exotic nuclear structures.
In the search for life on exoplanets, finding nothing is something too
Researchers estimate that detecting no signs of life on 40-80 exoplanets would allow for an upper limit on the prevalence of life in the universe. However, uncertainties and biases in individual observations must be carefully considered to ensure reliable results.
Does the universe behave the same way everywhere? Gravitational lenses could help us find out
Researchers propose a new methodology to test the Universe's isotropy using Euclid space telescope data, aiming to detect potential anisotropies that challenge the Standard Model of Cosmology. If confirmed, these findings would open a new chapter in cosmology, potentially revising our understanding of the Universe's behavior.
NTU Singapore-led discovery poised to help detect dark matter and pave the way to unravel the universe’s secrets
Researchers from NTU Singapore have developed a new crystal structure that shows naturally existing particles can behave like axions, promising to detect dark matter. The findings could lay the groundwork for understanding cosmic phenomena and uncovering the universe's greatest mysteries.
Eyes on the Sun: Naked thallium-205 ion decay reveals history over millions of years
Researchers at GSI Helmholtzzentrum für Schwerionenforschung GmbH measure half-life of thallium-205 ion decay to understand Sun's long-term stability and its connection to Earth's climate. The experiment, known as LOREX, provides insights into the Sun's evolutionary history.
Falsifying anthropics
A new paper in JCAP proposes a way to test the anthropic principle, which suggests the universe is fine-tuned for life. The proposal involves confirming three conditions: cosmic inflation, axion existence, and dark matter not being made of axions.
Glimmers of antimatter to explain the "dark" part of the universe
A recent study suggests that the observation of antihelium nuclei in cosmic rays may be consistent with the existence of WIMP particles, which could make up dark matter. The detection of two distinct isotopes, antihelium-3 and -4, is particularly intriguing as heavier nuclei are unlikely to be produced through natural processes.
How sweet is the milky way? Astrochemists are helping find out
Researchers have created a complex molecule in space-like conditions, finding glyceric acid, a key building block of life on Earth. This discovery fills an important gap in understanding the origin of life, suggesting that molecules essential for life may be more common in space than previously thought.
Black hole pairs may unveil new particles
Physicists from Amsterdam and Copenhagen suggest that a careful analysis of merging black hole pairs' gravitational waves could reveal the existence of new ultralight bosons. This process, called superradiance, provides an opportunity to probe these particles, which may resolve puzzles in astrophysics and particle physics.
ERC Starting Grant for neutrino research awarded to Dr. Zewei Xiong
Dr. Zewei Xiong has received an ERC Starting Grant to study collective neutrino oscillations in supernovae and neutron-star mergers. His project NeuTrAE aims to clarify lingering puzzles regarding neutrino flavor evolution, a crucial aspect of particle and nuclear astrophysics.
Nanohertz gravitational waves are cool but not supercool
A new study published in Physical Review Letters suggests that nanohertz gravitational waves may not originate from supercool first-order phase transitions. Researchers found that such transitions would struggle to complete, shifting the frequency of the waves away from nanohertz frequencies.
The rotation of a nearby star stuns astronomers
Astronomers have discovered a nearby star that rotates faster than expected, with anomalies in its stellar rotation profile. This finding provides insights into fundamental stellar strophysics and challenges current understanding of stellar dynamics and magnetic dynamos.
Dark matter seen through a forest
Researchers used hydrogen to track dark matter's presence in the universe, revealing a tension between observations and theoretical predictions. The findings suggest that an unknown particle or new physics may be responsible for this discrepancy.
Searching for dark matter with the coldest quantum detectors in the world
Researchers at Lancaster University and others are building the most sensitive dark matter detectors using quantum technologies. They aim to detect dark matter particles weighing between 0.01 to a few hydrogen atoms, which could reveal the mass and interactions of these mysterious particles.
What happens when neutron stars collide?
New simulations show that neutrinos created during neutron star collisions can be trapped at the interface of merging stars and interact with matter for 2-3 milliseconds. This brief out-of-equilibrium phase is crucial in understanding the physics of these extreme events.
Pair plasmas found in deep space can now be generated in the lab
Researchers at University of Rochester's Laboratory for Laser Energetics have developed a novel way to experimentally produce plasma 'fireballs' on Earth, generating high-density relativistic electron-positron pair plasmas. This breakthrough enables follow-up experiments that could yield fundamental discoveries about the universe.
X-ray satellite XMM-newton sees ‘space clover' in a new light
Astronomers have discovered an enormous circular radio feature around a galaxy, dubbed the Cloverleaf, which was created by clashing groups of galaxies. The XMM-Newton satellite has detected X-ray emission associated with this structure for the first time, revealing clues about its formation and the merger process.
A “cosmic glitch” in gravity
Researchers discovered a 'cosmic glitch' in the universe's gravity, explaining strange behavior on a cosmic scale. The new model modifies Einstein's general relativity, resolving inconsistencies without affecting existing uses.
Peptides on Interstellar Ice
A research team led by Dr. Serge Krasnokutski has discovered that peptides can form on cosmic dust particles even in the presence of water molecules. The study used a vacuum chamber to replicate interstellar conditions and found that the formation of peptides was slowed down but still occurred.
Scientists propose a new way to search for dark matter
Researchers at SLAC National Accelerator Laboratory propose detecting thermalized dark matter, which builds up on Earth's surface, using quantum sensors. The study suggests that superconducting quantum devices could be redesigned to detect low-energy galactic dark matter particles.
Astrophysical jet caught in a “speed trap”
The H.E.S.S. Observatory detected gamma-ray emission from the outer jets of SS 433, revealing a shift in energy-dependent morphology. This suggests strong shock acceleration, where high-energy particles collide with photons, producing x-ray radiation and explaining the X-ray reappearance of the jets.
NASA’s Fermi detects surprise gamma-ray feature beyond our galaxy
Astronomers have found an unexpected gamma-ray signal outside of our galaxy, with a magnitude 10 times greater than expected from Earth's motion. The discovery is linked to the highest-energy cosmic rays and may be related to unidentified sources producing both gamma-rays and ultrahigh-energy particles.
Nube, the almost invisible galaxy which challenges the dark matter model
The newly discovered galaxy Nube has a set of specific properties that distinguish it from previously known objects, including being ten times fainter and ten times more extended than other dwarf galaxies. Its unusual characteristics challenge the current understanding of the universe, particularly the dark matter model.
New astrophysics model sheds light on additional source of long gamma-ray bursts
A new unified model confirms that some long-lasting gamma-ray bursts are created in the aftermath of cosmic mergers that spawn an infant black hole surrounded by a giant disk of natal material. The findings explain recently observed long GRBs that astronomers couldn't link to collapsing stars.
Study finds strongest evidence yet for local sources of cosmic ray electrons
A new study using CALET data finds evidence for nearby, young sources of cosmic ray electrons, contributing to a greater understanding of the galaxy. The study suggests that these high-energy electrons originate in supernova remnants, offering insights into the galaxy and its sources.
Exploding stars
Researchers from Helmholtz-Zentrum Dresden-Rossendorf are studying near-Earth cosmic explosions to understand their potential impact on the Earth's biosphere. They found that ejected debris can reach our solar system, with some isotopes, such as iron-60 and plutonium-244, potentially coming from supernovae or other galactic events.
Ionic crystal generates molecular ions upon positron irradiation, finds new study
Researchers at Tokyo University of Science have discovered a method to generate molecular ions from an ionic crystal by bombarding it with positrons. This breakthrough could lead to new applications in materials science, cancer therapy, and quantum computing.
Pulsars may make dark matter glow
Scientists propose that pulsars could detect dark matter by observing a subtle additional glow. If axions are produced in strong electromagnetic fields around pulsars, they could convert into observable light.
Astronomers discover new link between dark matter and clumpiness of the universe
Researchers at the University of Toronto have made a breakthrough in understanding dark matter and its impact on the universe's large-scale structure. By analyzing cosmic microwave background data and galaxy clustering patterns, they suggest that ultra-light axion particles could account for the observed lack of clumpiness.
CALorimetric Electron Telescope (CALET) captures charge-sign dependent cosmic ray modulation
The CALorimetric Electron Telescope (CALET) study found that the movement of cosmic rays is affected by the Sun's magnetic field, causing fluctuations in galactic cosmic rays reaching Earth. The research indicates that electrons are more susceptible to solar modulation than protons.