Articles tagged with "particle-physics"
CERN's ALICE detector explains how light nuclei form in LHC collisions
The ALICE Collaboration at CERN has resolved a longstanding puzzle about how fragile light nuclei, specifically deuterons, form and survive in the extreme conditions created by proton collisions at the Large Hadron Collider (LHC). Despite the collisions generating energies around 100 MeV per particle—far exceeding the 2.23 MeV binding energy of deuterons—these nuclei not only form but remain intact. Using precision particle tracking and deuteron-pion femtoscopy, ALICE demonstrated that approximately 89% of antideuterons do not form immediately in the initial high-energy fireball. Instead, they assemble later from protons and neutrons released by short-lived resonances at much lower energies (~20 MeV), where stable binding becomes possible. This finding has significant implications beyond collider physics, impacting cosmic ray experiments and dark matter detection efforts that rely on accurate models of antideuteron production. The breakthrough was enabled by advances in detector technology and data analysis at ALICE, which is
materialsparticle-physicsnuclear-matterLarge-Hadron-ColliderALICE-detectorquark-gluon-plasmaparticle-trackingQuantum detectors could 'see' dark matter velocity with new method
Researchers from the University of Tokyo and Chuo University have proposed a novel method to detect light dark matter particles by employing a network of distributed quantum sensors. Unlike traditional detectors that rely on observing particle collisions or recoil tracks, this approach leverages quantum measurement protocols across spatially extended detectors to extract information about the velocity and arrival direction of dark matter. This method is applicable to any dark matter detector capable of quantum data acquisition, making it a versatile tool for probing sub-GeV dark matter candidates, which behave more like waves than particles. The new strategy addresses limitations of current detection techniques that struggle to measure the velocity of light dark matter due to their reliance on discrete excitation modes. By treating data from multiple quantum sensors collectively, the researchers can infer dark matter’s movement without needing spatially extended signals. Analytical assessments suggest that this quantum sensor array offers higher sensitivity than classical methods and does not depend on specific particle interactions or detector geometries. The team envisions refining this technique further to map dark matter distributions, potentially opening
quantum-sensorsdark-matter-detectionquantum-measurementparticle-physicshigh-energy-physicsquantum-engineeringsensor-networksPhysicist solves fusion reactor problem shown in ‘The Big Bang Theory’
A team of physicists led by Professor Jure Zupan at the University of Cincinnati, in collaboration with researchers from Fermi National Laboratory, MIT, and Technion-Israel Institute of Technology, has theoretically solved a fusion reactor problem previously depicted as unsolvable in the TV sitcom "The Big Bang Theory." The problem involved producing hypothetical subatomic particles called axions—candidates for dark matter—in fusion reactors. While the show's characters Sheldon Cooper and Leonard Hofstadter attempted and failed to solve this issue in the fifth season, Zupan’s team developed a theoretical framework explaining how axions could be generated in reactors fueled by deuterium and tritium and lined with lithium, such as the ITER reactor under development in France. The researchers found that axions or axion-like particles could be produced through nuclear reactions triggered by neutron flux interacting with the reactor walls, or via bremsstrahlung radiation when neutrons scatter and slow down. This discovery provides a potential method to detect or produce dark matter
energyfusion-reactoraxionsdark-matternuclear-reactionsparticle-physicsbremsstrahlungWorld’s largest cryogenic refrigerator gets giant cold boxes at CERN
CERN has recently installed two massive cold boxes at the ATLAS and CMS experiment sites as part of the upgraded cryogenic system for the High-Luminosity Large Hadron Collider (HL-LHC), scheduled to begin operations around 2030. These cold boxes, each 16 meters long and 3.5 meters in diameter, were manufactured by Linde in Germany and transported via a complex route involving river barges and road transport. Their installation follows the earlier placement of six compression units and is critical to increasing the cooling capacity needed for the HL-LHC, which will feature more powerful focusing magnets and new cavities generating higher thermal loads. The existing LHC is already the world’s largest cryogenic installation, maintaining 23 kilometers of its 27-kilometer ring at 1.9 kelvin (-271 °C) using superfluid helium refrigerators. To support the HL-LHC’s increased luminosity and associated thermal demands, two additional large refrigerators are being added to the eight units currently
energycryogenicscooling-systemssuperconducting-magnetshelium-refrigerationparticle-physicsLarge-Hadron-ColliderPhysics team detects first carbon reaction caused by neutrinos
Scientists from the SNO+ experiment at SNOLAB in Canada have reported the first direct evidence of solar neutrinos interacting with carbon-13 nuclei, transforming them into nitrogen-13. This rare reaction was detected using a 12-meter detector sphere equipped with 9,000 sensors, located 1.24 miles underground to shield from cosmic rays and background noise. By employing a delayed-coincidence technique—observing an initial neutrino-induced flash followed by a secondary flash from nitrogen-13 decay about ten minutes later—the team isolated 5.6 such events over 231 days, closely matching theoretical predictions. This milestone builds on decades of neutrino research, including the original SNO experiment that demonstrated neutrino flavor oscillations and earned a Nobel Prize in 2015. The detection represents the lowest-energy observation of neutrino interactions with carbon-13 nuclei to date and provides the first direct measurement of the reaction’s cross-section to the nitrogen-13 ground state. Researchers emphasize that this achievement not
materialscarbon-13neutrinosnuclear-reactionsparticle-physicssolar-neutrinosdetectorsGiant underground detector inches nearer to detecting true dark matter
The LUX-ZEPLIN (LZ) dark matter experiment, located nearly a mile underground at the Sanford Underground Research Facility in South Dakota, has made significant progress in the search for dark matter, which constitutes about 85% of the universe yet remains largely mysterious. The international research team focused on detecting weakly interacting massive particles (WIMPs), a leading dark matter candidate hypothesized to have originated in the early universe. Using a 10-tonne liquid xenon detector, they explored WIMP masses between five and ten GeV/c², a previously uncharted energy range, and successfully identified boron-8 neutrino signals—tiny particles from the Sun that interact with xenon similarly to how dark matter particles are expected to. These findings mark a new milestone by demonstrating the detector’s sensitivity to signals at low masses, effectively opening a new observational window for dark matter detection. The presence of known neutrino signals confirms that the LUX-ZEPLIN experiment is operating as intended
energydark-matter-detectionLUX-ZEPLINparticle-physicsunderground-detectorxenon-detectorneutrino-signalsWorld’s largest neutrino detector built in China surpasses expectations in physics results
China’s Jiangmen Underground Neutrino Observatory (JUNO), the world’s largest and most advanced neutrino detector, has exceeded expectations in its initial physics results. After more than a decade of development and international collaboration, JUNO began operations in August 2025 and quickly demonstrated unprecedented precision in measuring neutrino oscillation parameters. Within just 59 days of data collection, JUNO measured the solar neutrino oscillation parameters θ12 and Δm221 with 1.6 times better precision than all previous experiments combined. This measurement confirmed a previously observed mild discrepancy between solar and reactor neutrino results, known as the solar neutrino tension, which JUNO is uniquely positioned to investigate further. The detector, featuring a 20-kiloton liquid scintillator core surrounded by a water Cherenkov veto and plastic scintillator veto layers, was constructed underground to minimize background interference. Its design and performance reflect cutting-edge technology and the combined expertise of international research groups. JUNO’s early success signals its
energyneutrino-detectorparticle-physicsliquid-scintillatorhigh-precision-measurementunderground-laboratoryscientific-instrumentationCERN turbocharges antimatter output with bold cooling technique
CERN’s ALPHA experiment has achieved a major breakthrough in antimatter production by developing a novel cooling technique that dramatically increases the yield of antihydrogen atoms. By introducing laser-cooled beryllium ions into a Penning trap containing positrons, the team employed sympathetic cooling to lower the positrons’ temperature to about −266°C. This significant reduction in energy made the positrons far more likely to bind with antiprotons, enabling the production of over 15,000 antihydrogen atoms in under seven hours—a process that previously took weeks. This eightfold increase in efficiency marks a transformative advance in antimatter research. The enhanced production capability has allowed the ALPHA collaboration to generate more than two million antihydrogen atoms during the 2023–24 experimental runs, facilitating faster and more detailed investigations into antimatter’s properties. One key application is the ALPHA-g experiment, which studies how gravity affects antimatter, a fundamental question in physics. The ability to rapidly accumulate large datasets
materialsantimattercooling-techniqueparticle-physicsCERNantihydrogenlaser-coolingChina tests deep-sea ‘Spider’ to track ghostly cosmic neutrinos
Chinese scientists from Shanghai Jiao Tong University’s Tsung-Dao Lee Institute have successfully conducted a full-scale sea trial of a device called the Subsea Precision Instrument Deployer with Elastic Releasing (Spider). This device is critical for deploying sensors needed to build the Hailing Tropical Deep-sea Neutrino Telescope (Trident) in the South China Sea. During the trial, the Spider descended to about 1,700 meters depth, uncoiling a 700-meter string with 20 sensors and buoyancy blocks, precisely positioning them to detect elusive neutrinos—nearly massless subatomic particles born in cosmic events. This successful test marks a significant step toward constructing the large-scale underwater neutrino observatory designed to capture rare neutrino interactions in a quiet, dark, and stable deep-sea environment. The Trident telescope will be located approximately 3,500 meters below the ocean surface, where conditions such as absence of sunlight, minimal vibrations, and low natural radiation optimize the detection of
robotdeep-sea-technologyunderwater-sensorsneutrino-detectionscientific-instrumentsparticle-physicsocean-engineeringWorld’s most sensitive dark matter detector cuts radon by billionfold
The XENON Collaboration, operating one of the world’s most sensitive dark matter detectors at Italy’s Gran Sasso Laboratory, has achieved a major breakthrough by drastically reducing background radioactivity caused by radon gas inside their detector. Using an advanced cryogenic distillation system, the team lowered radon concentrations to about 430 atoms per metric ton of liquid xenon—approximately a billion times less than natural radiation levels found in the human body. This reduction minimizes false signals that could mimic dark matter interactions, pushing the experiment into a sensitivity regime limited only by neutrino background, which cannot be shielded against. The detector contains 8.5 metric tons of liquid xenon cooled to minus 95 degrees Celsius and is located deep underground to shield it from cosmic radiation. Radon, a decay product of ancient elements, has been a persistent source of interference due to its radioactive decay producing light flashes in the detector. The new purification technology represents a significant step toward directly detecting dark matter, which is believed to
materialsdark-matter-detectionradon-reductionliquid-xenoncryogenic-distillationparticle-physicsradiation-shieldingProton's unexpected behavior challenges decades of excited state theory
Physicists at the US Department of Energy’s Thomas Jefferson National Accelerator Facility have discovered that protons’ excited states, or resonances, persist at high momentum transfers far beyond previous expectations. Using the CLAS12 spectrometer and an electron beam from the Continuous Electron Beam Accelerator Facility (CEBAF), researchers probed the proton’s internal structure across a broad range of energies, spanning from strongly coupled quark-gluon interactions to the perturbative regime where interactions weaken. Contrary to longstanding assumptions that resonance signals would diminish at high energies, the experiment showed these signatures remain clearly visible throughout the entire resonance region. This finding challenges decades of theoretical understanding about proton structure and has significant implications for Quantum Chromodynamics (QCD), the theory describing the strong force binding quarks and gluons. The ability of CLAS12 to measure the resonance region comprehensively in a single experiment provides a novel framework to refine QCD predictions and deepen insight into how quarks and gluons form matter. Led by Valerii
energyprotonparticle-physicsCEBAFCLAS12quarksgluonsBreakthrough quantum algorithm solves a century-old math problem
Researchers have successfully employed a quantum algorithm to solve a century-old mathematical problem involving the factorization of group representations—a task previously deemed intractable for classical supercomputers. Conducted by Martín Larocca of Los Alamos National Laboratory and Vojtěch Havlíček of IBM, the study demonstrates that quantum computers can efficiently decompose complex symmetries into their fundamental building blocks, known as irreducible representations. This problem is analogous to prime factorization but applies to group theory, which is essential for describing system transformations in physics and material science. The breakthrough leverages quantum Fourier transforms, enabling computations that classical algorithms struggle with due to exponential complexity. This achievement exemplifies a clear quantum advantage, showcasing quantum computing’s potential to outperform classical methods on meaningful scientific problems. The ability to factor group representations efficiently has significant real-world applications, including calibrating particle detectors in physics, developing error-correcting codes in data transmission, and analyzing material properties for new material design. The research not only
quantum-computingquantum-algorithmsmaterials-sciencequantum-advantagecomputational-physicsquantum-Fourier-transformparticle-physicsPhysicists propose tabletop “neutrino laser” to probe ghost particles
MIT physicists have proposed a novel concept for a neutrino laser—a quantum device that could emit coherent, intense beams of neutrinos by synchronizing the radioactive decay of atoms cooled to near absolute zero. The idea involves cooling a gas of radioactive rubidium-83 atoms into a Bose-Einstein condensate, a quantum state where atoms act collectively. This synchronization could accelerate neutrino emission from a process that normally takes months to just minutes, producing a rapid, coherent neutrino beam analogous to the photon emission in conventional lasers. This approach leverages the principle of superradiance, where atoms emit light in unison to amplify the output, applied here to neutrino emission. If realized, the neutrino laser could have significant implications beyond fundamental physics. Because neutrinos interact very weakly with matter, such a beam could enable communication through Earth or deep space without interference, potentially benefiting underground or extraterrestrial communication systems. Additionally, the radioactive decay involved also produces isotopes useful in medical imaging and cancer diagnostics
energyquantum-physicsneutrino-laserradioactive-decayBose-Einstein-condensateparticle-physicssuperradianceChina’s underground neutrino lab JUNO begins hunt for ghost particles
China’s Jiangmen Underground Neutrino Observatory (JUNO) officially began data collection on August 26, 2025, after more than a decade of development. Located 700 meters underground to shield it from cosmic rays, JUNO features a massive 35.4-meter diameter acrylic sphere filled with 20,000 tons of liquid scintillator. This detector is designed to capture faint flashes of light produced when antineutrinos interact with the liquid, with tens of thousands of photomultiplier tubes converting these signals into data for analysis. JUNO’s primary scientific goal is to resolve the long-standing mystery of neutrino mass ordering—determining which of the three neutrino types is heaviest or lightest—by precisely measuring the energy spectrum of antineutrinos. Beyond neutrino mass ordering, JUNO aims to deliver highly precise measurements of neutrino properties and explore a range of phenomena, including neutrinos from the Sun and supernovae, potential new neutrino types, and
materialsparticle-physicsneutrino-detectoracrylic-spherephotomultiplier-tubesliquid-scintillatorunderground-laboratoryGRETA: World's most powerful detector to decode nuclear 'fingerprints
The Gamma-Ray Energy Tracking Array (GRETA) is the world’s most powerful detector designed to study atomic nuclei by tracking gamma rays with 10 to 100 times greater sensitivity than previous instruments. Developed by a team led by the US Department of Energy’s Lawrence Berkeley National Laboratory, GRETA consists of 30 ultra-pure germanium detector modules arranged in a spherical array, cooled to about -300°F for maximum sensitivity. By using particle beams to create unstable nuclei that emit gamma rays as they stabilize, GRETA captures the unique “fingerprints” of isotopes, enabling scientists to explore fundamental questions about nuclear structure, element formation in stars, and the matter-antimatter asymmetry in the universe. GRETA builds on its predecessor, GRETINA, by expanding the detector array and incorporating advanced electronics and computing systems. Argonne National Laboratory contributed a crucial trigger system to efficiently process the vast data generated, while artificial intelligence is being applied to enhance gamma-ray path reconstruction. The detector recently demonstrated the
energynuclear-detectiongamma-ray-trackinggermanium-detectorsartificial-intelligencehigh-sensitivity-instrumentationparticle-physicsThe Mysterious Origins of the Most Energetic Neutrino Ever Detected
In February 2023, a deep-sea cosmic particle detector in the Mediterranean recorded an extraordinarily energetic neutrino, designated KM3-230213A, with an estimated energy of 220 petaelectronvolts (PeV). This energy level is 20 to 30 times greater than any neutrino previously documented, surpassing the former record of 10 PeV. Neutrinos are fundamental, chargeless particles with very small mass that rarely interact with matter, earning them the nickname “ghost particles.” The detection of such an ultra-energetic neutrino sparked excitement and debate among physicists, who considered whether the event represented a novel cosmic phenomenon or a measurement error. Subsequent analysis published in Physical Review X confirmed that the neutrino was not a statistical anomaly. Despite confirming the neutrino’s authenticity, scientists remain uncertain about its exact origin. The data available do not allow firm conclusions about whether KM3-230213A signals a new ultra-high-energy component in the neutrino
energyneutrinocosmic-particlesparticle-physicshigh-energy-physicsastrophysicscosmic-raysColumbia's radiation-proof chip built to decode the universe at CERN
Columbia University engineers have developed a specialized, radiation-hardened analog-to-digital converter (ADC) chip designed for CERN’s Large Hadron Collider (LHC) upgrade, specifically for use in the ATLAS detector. This custom silicon chip can capture and digitize signals from up to 1.5 billion particle collisions per second, a significant increase from the current 400 million collisions per second. The chip’s resilient design allows it to operate reliably in the LHC’s extreme radiation environment, where standard commercial electronics fail. By converting analog signals from the liquid argon calorimeter into precise digital data, these ADC chips enable scientists to analyze particle collisions with unprecedented detail. Due to the intense radiation and the niche market for radiation-resistant electronics, commercial components were unsuitable, prompting Columbia’s team to create their own robust solution using existing circuit-level techniques. Two versions of these chips are integral to the ATLAS experiment: one acts as a “digital gatekeeper,” filtering collisions to select the most promising events
materialsradiation-hardened-chipssilicon-chipparticle-physicsLarge-Hadron-Collideranalog-to-digital-converterCERNCompact neutrino experiment unlocks first-ever reactor mystery
Scientists at the Max Planck Institute for Nuclear Physics (MPIK) have successfully detected antineutrinos from a nuclear reactor using the compact CONUS+ experiment, which employs a small 3 kg germanium semiconductor detector. Positioned 20.7 meters from the core of the Leibstadt nuclear power plant in Switzerland, the detector recorded an excess of 395±106 neutrino signals over 119 days, confirming the observation of Coherent Elastic Neutrino-Nucleus Scattering (CEvNS) at full coherence from a reactor source. This process, where low-energy neutrinos scatter off entire atomic nuclei, had previously only been observed at particle accelerators, making this the first such detection at reactor energies. The CONUS+ experiment’s results align well with theoretical predictions and demonstrate the feasibility of using small, mobile detectors to monitor reactor neutrino emissions. This breakthrough offers new opportunities for fundamental physics research, including tests of the Standard Model with reduced nuclear physics uncertainties and enhanced sensitivity to potential new physics
energynuclear-reactorneutrino-detectionsemiconductor-detectorsparticle-physicsCoherent-Elastic-Neutrino-Nucleus-ScatteringCONUS+-experiment5th force of nature: Scientists to hunt dark matter with new physics
Scientists at ETH Zurich are conducting highly precise ion trap experiments to search for a hypothetical fifth fundamental force of nature that could help explain dark matter, an elusive form of matter known only through its gravitational effects. Unlike the four established forces—gravity, electromagnetism, and the strong and weak nuclear forces—this proposed fifth force is theorized to act between neutrons in an atomic nucleus and orbiting electrons, mediated by a new, unknown particle. The team uses precision atomic spectroscopy on different calcium isotopes, which have the same number of protons but varying neutrons, to detect tiny shifts in energy levels that would indicate the presence of this force. The experiment involves trapping single charged calcium isotopes with electromagnetic fields and measuring the frequency of light emitted during energy transitions with unprecedented accuracy—100 times more precise than previous attempts. Complementary studies in Germany involving highly charged calcium ions and nuclear mass ratio measurements support the findings. While the observed deviations in energy shifts cannot be fully explained by known nuclear effects, alternative
materialsion-trapatomic-physicsdark-matterisotopesparticle-physicsspectroscopyBreakthrough math model could unlock 3,836 mph hypersonic flight
Researchers at San Diego State University, in collaboration with Stanford University, have developed a novel computational mathematics model that simulates the behavior of gas and fuel droplets in detonation waves occurring in hypersonic propulsion systems such as scramjets and rotating detonation engines. This model, termed the Liouville method, builds on classical equations like the Fokker–Planck and Langevin models to predict particle dynamics at speeds exceeding Mach 5 (approximately 3,836 mph). Funded by the US Air Force Office of Scientific Research, the model provides new insights into the stability and thermal behavior of gases near hypersonic vehicles, addressing critical challenges that arise when flight conditions become unstable at these extreme speeds. Beyond its primary application in advancing hypersonic military aircraft design, the model has potential interdisciplinary uses in climate science and medicine, where understanding particle dynamics and shock wave interactions is essential. For example, it could improve climate modeling by better describing particle behavior in the atmosphere and assist medical techniques that use
energyhypersonic-flightcomputational-modelingscramjet-enginesrocket-propulsionparticle-physicsaerospace-engineering