A recent Physical Review Letters study presents a new model for quark star merger ejecta that could resolve whether these cosmic collisions generate ordinary matter or something different.
Category: particle physics – Page 12
World’s most sensitive detector tightens the net on elusive dark matter
Determining the nature of dark matter, the invisible substance that makes up most of the mass in our universe, is one of the greatest puzzles in physics. New results from the world’s most sensitive dark matter detector, LUX-ZEPLIN (LZ), have narrowed down the possibilities for one of the leading dark matter candidates: weakly interacting massive particles (WIMPs).
High-order analysis reveals more signs of phase-change ‘turbulence’ in nuclear matter
Members of the STAR collaboration, a group of physicists collecting and analyzing data from particle collisions at the Relativistic Heavy Ion Collider (RHIC), have published a new high-precision analysis of data on the number of protons produced in gold-ion smashups over a range of energies.
The results, published in Physical Review Letters, suggest scientists have observed one part of a key signature of a “critical point.” That’s a unique point on the “map” of nuclear phases that marks a change in the way quarks and gluons, the building blocks of protons and neutrons, transition from one phase of matter to another.
Discovering the critical point has been a central goal of research at RHIC, a U.S. Department of Energy (DOE) Office of Science user facility for nuclear physics research at DOE’s Brookhaven National Laboratory. Like centuries-old efforts to map out the solid, liquid, and gaseous phases of substances like water, it’s considered essential for fully understanding and describing the quark-gluon plasma.
In a first, scientists observe short-range order in semiconductors
Inside the microchips powering your devices, atoms aren’t just randomly scattered. They follow a hidden order that can change how semiconductors behave.
A team of researchers from the Lawrence Berkeley National Laboratory (Berkeley Lab) and George Washington University has, for the first time, observed these tiny patterns, called short-range order (SRO), directly in semiconductors.
This discovery is a game-changer, as understanding how atoms naturally arrange themselves could let researchers design materials with desirable electronic properties. Such control could revolutionize quantum computing, neuromorphic devices that mimic the brain, and advanced optical detectors.
The surprising new particle that could finally explain dark matter
Physicists are eyeing charged gravitinos—ultra-heavy, stable particles from supergravity theory—as possible Dark Matter candidates. Unlike axions or WIMPs, these particles carry electric charge but remain undetectable due to their scarcity. With detectors like JUNO and DUNE, researchers now have a chance to spot their unique signal, a breakthrough that could link particle physics with gravity.
Controlling Light Emission with Photonic Time Crystals
A material whose dielectric properties vary in time could produce exotic light-emission phenomena in a nearby atom, theorists predict.
Traditional photonic technologies rely on mirrors, lenses, and diffraction gratings to shape light as it travels through a medium. Recent advances in material science have opened a strikingly different route. Instead of sculpting material properties in space, researchers can now dynamically modulate them in time [1]. Such temporal modulation transforms a passive medium into an active one, as the act of modulation itself can inject or extract energy. Adding a temporal dimension to material design confronts long-standing notions of light–matter interactions and reveals phenomena with no static counterpart. Now Bumki Min of the Korea Advanced Institute of Science and Technology (KAIST) and his collaborators have exploited this capability to reshape the photonic density of states (DOS), which quantifies the number of available optical modes into which light can be emitted [2].
3D particle-in-cell simulations demonstrate first true steady state in turbulent plasma
Plasma is a state of matter that emerges when a gas is heated to sufficiently high temperatures, prompting some electrons to become free from atoms. This state of matter has been the focus of many astrophysical studies, as predictions suggest that it would be found in the proximity of various cosmological objects, including pulsars and black holes.
Previous research findings suggest that the environment around these celestial objects is turbulent, which essentially means that magnetic fields and electric fields within it fluctuate chaotically across many scales. These chaotic fluctuations would in turn influence the movements and acceleration of particles.
Researchers have been trying to reproduce the turbulent environment associated with the emergence of plasma in space using numerical simulations. However, they were so far unable to realize a steady state in which a system’s properties no longer change over time, such as that one might observe in real cosmic systems.
Atomic neighborhoods in semiconductors provide new avenue for designing microelectronics
Inside the microchips powering the device you’re reading this on, the atoms have a hidden order all their own. A team led by Lawrence Berkeley National Laboratory (Berkeley Lab) and George Washington University has confirmed that atoms in semiconductors will arrange themselves in distinctive localized patterns that change the material’s electronic behavior.
The research, published in Science, may provide a foundation for designing specialized semiconductors for quantum-computing and optoelectronic devices for defense technologies.
On the atomic scale, semiconductors are crystals made of different elements arranged in repeating lattice structures. Many semiconductors are made primarily of one element with a few others added to the mix in small quantities. There aren’t enough of these trace additives to cause a repeating pattern throughout the material, but how these atoms are arranged next to their immediate neighbors has long been a mystery.