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Astrophysicists have long been intrigued by the possibility of dark stars-massive celestial objects fueled not by nuclear fusion but by the enigmatic energy of dark matter. Thanks to images taken by the James Webb Space Telescope (JWST), the scientific community has perhaps also found signs of such elusive entities. Could these dark stars, which shine billions of times brighter than our sun, rewrite the story of the universe’s infancy?

Dark stars, despite the word “dark”, are hypothesized luminous sources that may have existed in the universe’s infancy. In contrast to traditional stars that work with nuclear fusion, dark stars are speculated to obtain their energy from self-annihilation of dark matter particles.

As a result, energy is released that warms the ambient hydrogen and helium, and this leads the primordial clouds to glow brightly and expand to enormous scale-some up to a million times mass of the sun. These stars may have also been born in “minihaloes”, dense pockets of dark matter in the early universe.

Commonwealth Fusion Systems (CFS) is developing a tokamak device called SPARC. The company aims to demonstrate the critical fusion energy milestone of producing more output power than input power for the first time in a device that can scale up to commercial power plant size. However, this achievement is only possible if the plasma doesn’t melt the device.

Researchers from CFS and Oak Ridge National Laboratory (ORNL) have collaborated on fusion boundary research through a series of projects, including ORNL Strategic Partnership Projects and Laboratory Directed Research and Development projects, work under the Innovation Network for Fusion Energy (INFUSE), and other work in partnership with General Atomics.

Throughout this collaboration, ORNL has developed simulation capabilities required to address critical and time-sensitive design issues for the SPARC .

A new analysis of data from the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) reveals fresh evidence that collisions of even very small nuclei with large ones might create tiny specks of a quark-gluon plasma (QGP). Scientists believe such a substance of free quarks and gluons, the building blocks of protons and neutrons, permeated the universe a fraction of a second after the Big Bang.

RHIC’s energetic smashups of gold ions—the nuclei of gold atoms that have been stripped of their electrons—routinely create a QGP by “melting” these nuclear building blocks so scientists can study the QGP’s properties.

Physicists originally thought that collisions of smaller ions with large ones wouldn’t create a QGP because the small ion wouldn’t deposit enough energy to melt the large ion’s protons and neutrons. But evidence from PHENIX has long suggested that these small collision systems generate particle flow patterns that are consistent with the existence of tiny specks of the primordial soup, the QGP.

A joint research team from Hefei Institutes of Physical Science of the Chinese Academy of Sciences has successfully developed a continuous cryogenic pellet injection system for tokamak fueling. This innovative system addresses key technical challenges associated with cryogenic ice formation, pellet cutting, and launching.

Cryogenic pellet injection is a state-of-the-art technique in fusion research. It involves condensing hydrogen isotopic gases into solid ice pellets, which are then accelerated and injected into plasma. This method allows for deep particle and high fueling efficiency, making it crucial for the future of fusion reactors.

It is recognized as a critical fueling technology for next-generation fusion devices, including the International Thermonuclear Experimental Reactor (ITER), the China Fusion Engineering Test Reactor (CFETR), and the European Demonstration Fusion Reactor (EU-DEMO).

The development of sustainable energy sources that can satisfy the world energy demand is one of the most challenging scientific problems. Nuclear fusion, the energy source of stars, is a clean and virtually unlimited energy source that appears as a promising candidate.

The most promising fusion reactor design is based on the tokamak concept, which uses magnetic fields to confine the plasma. Achieving high confinement is key to the development of power plants and is the final aim of ITER, the largest tokamak in the world currently under construction in Cadarache (France).

The plasma edge stability in a tokamak plays a fundamental role in plasma confinement. In present-day tokamaks, edge instabilities, magnetohydrodynamic waves known as ELMs (edge localized modes), lead to significant particle and energy losses, like solar flares on the edge of the sun. The particle and energy losses due to ELMs can cause erosion and excessive heat fluxes onto the plasma-facing components, at levels unacceptable in future burning plasma devices.

Chinese researchers say that recent advancements in the burgeoning field of inertial confinement fusion are bringing us one step closer to making accessible nuclear fusion a reality.

The new findings, which incorporate innovative new modeling approaches, could open new avenues for the exploration of the mysteries surrounding high-energy-density physics, and could potentially offer a window toward understanding the physics of the early universe.

Harnessing controlled nuclear fusion as a potential source of clean energy has seen several significant advancements in recent years, and the recent research by a Chinese team, funded by the Strategic Priority Research Program of Chinese Academy of Sciences and published in Science Bulletin last month, signals the next wave of insights with what the team calls a “surprising observation” involving supra-thermal ions during observations of fusion burning plasmas at National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in California.

Nuclear fission is the most reliable source of antineutrinos, but they are difficult to characterize. A recent study suggests how their emission can be simulated most effectively.

Antineutrinos are mysterious fundamental anti-particles with no charge and an exceptionally small but non-zero mass. The JUNO project (Jiangmen Underground Neutrino Observatory) in China is a large scintillation detector designed to detect them and to characterize their properties, particularly in precise measurements of that tiny mass. Anti-particles are hard to measure and even harder to control, even when they come from a strong and reliable source.

A group of Italian physicists, led by Monica Sisti of the Istituto Nazionale di Fisica Nucleare (INFN) in Milan and Antonio Cammi of the Politecnico di Milano and part of the JUNO collaboration of over 700 scientists from 17 countries, has now modeled parameters that determine the ‘antineutrino spectrum’ emitted by a source.