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Reçu hier — 13 janvier 2026 6.5 📰 Sciences English

There’s no end in sight for a space ‘nuclear renaissance’

13 janvier 2026 à 17:00
Concept art for Zeno Power’s radioisotope power system satellite, a spacecraft bearing a Antares Mark-0 reactor, and Lockheed Martin’s fission surface power system on the surface of the moon. Credit: Zeno Power/Antares/Lockheed Martin/SpaceNews Illustration

A widespread demand for nuclear power has led some to call this period a “nuclear renaissance,” one that will continue to build momentum in 2026. This growing need is being driven by two primary use cases: small modular nuclear reactors for cloud infrastructure and terrestrial data center needs, and nuclear electric reactors for lunar surface […]

The post There’s no end in sight for a space ‘nuclear renaissance’ appeared first on SpaceNews.

CERN team solves decades-old mystery of light nuclei formation

13 janvier 2026 à 15:00

When particle colliders smash particles into each other, the resulting debris cloud sometimes contains a puzzling ingredient: light atomic nuclei. Such nuclei have relatively low binding energies, and they would normally break down at temperatures far below those found in high-energy collisions. Somehow, though, their signature remains. This mystery has stumped physicists for decades, but researchers in the ALICE collaboration at CERN have now figured it out. Their experiments showed that light nuclei form via a process called resonance-decay formation – a result that could pave the way towards searches for physics beyond the Standard Model.

Baryon resonance

The ALICE team studied deuterons (a bound proton and neutron) and antideuterons (a bound antiproton and antineutron) that form in experiments at CERN’s Large Hadron Collider. Both deuterons and antideuterons are fragile, and their binding energies of 2.2 MeV would seemingly make it hard for them to form in collisions with energies that can exceed 100 MeV – 100 000 times hotter than the centre of the Sun.

The collaboration found that roughly 90% of the deuterons seen after such collisions form in a three-phase process. In the first phase, an initial collision creates a so-called baryon resonance, which is an excited state of a particle made of three quarks (such as a proton or neutron). This particle is called a Δ baryon and is highly unstable, so it rapidly decays into a pion and a nucleon (a proton or a neutron) during the second phase of the process. Then, in the third (and, crucially, much later) phase, the nucleon cools down to a point where its energy properties allow it to bind with another nucleon to form a deuteron.

Smoking gun

Measuring such a complex process is not easy, especially as everything happens on a length scale of femtometres (10-15 meter). To tease out the details, the collaboration performed precision measurements to correlate the momenta of the pions and deuterons. When they analysed the momentum difference between these particle pairs, they observed a peak in the data corresponding to the mass of the Δ baryon. This peak shows that the pion and the deuteron are kinematically linked because they share a common ancestor: the pion came from the same Δ decay that provided one of the deuteron’s nucleons.

Panos Christakoglou, a member of the ALICE collaboration based at the Netherlands’ Maastricht University, says the experiment is special because in contrast to most previous attempts, where results were interpreted in light of models or phenomenological assumptions, this technique is model-independent. He adds that the results of this study could be used to improve models of high energy proton-proton collisions in which light nuclei (and maybe hadrons more generally) are formed. Other possibilities include improving our interpretations of cosmic-ray studies that measure the fluxes of (anti)nuclei in the galaxy – a useful probe for astrophysical processes.

The hunt is on

Intriguingly, Christakoglou suggests that the team’s technique could also be used to search for indirect signs of dark matter. Many models predict that dark-matter candidates such as Weakly Interacting Massive Particles (WIMPs) will decay or annihilate in processes that also produce Standard Model particles, including (anti)deuterons. “If for example one measures the flux of (anti)nuclei in cosmic rays being above the ‘Standard Model based’ astrophysical background, then this excess could be attributed to new physics which might be connected to dark matter,” Christakoglou tells Physics World.

Michael Kachelriess, a physicist at the Norwegian University of Science and Technology in Trondheim, Norway, who was not involved in this research, says the debate over the correct formation mechanism for light nuclei (and antinuclei) has divided particle physicists for a long time. In his view, the data collected by the ALICE collaboration decisively resolves this debate by showing that light nuclei form in the late stages of a collision via the coalescence of nucleons. Kachelriess calls this a “great achievement” in itself, and adds that similar approaches could make it possible to address other questions, such as whether thermal plasmas form in proton-proton collisions as well as in collisions between heavy ions.

The post CERN team solves decades-old mystery of light nuclei formation appeared first on Physics World.

Turion Space Corp. Acquires Tychee Research Group to Accelerate Autonomous Space Operations and Mission Engineering

13 janvier 2026 à 15:00
Turion Space logo Square

IRVINE, Calif. & LOS ANGELES, Calif. — January 13, 2026 — Turion Space Corp. (“Turion”), a space infrastructure company that builds and operates mission-grade spacecraft and space operations software, today […]

The post Turion Space Corp. Acquires Tychee Research Group to Accelerate Autonomous Space Operations and Mission Engineering appeared first on SpaceNews.

2026 will be the year of space nuclear power and surviving the lunar night

Lunar night survival becomes an imperative “Surviving the lunar night has crossed a critical threshold: what was once a ‘nice-to-have’ is now the imperative for any serious lunar mission. We’re seeing this ‘survive, operate, thrive’ progression play out in real time: we’ve proven we can land repeatedly, now we’re focused on surviving that brutal two-week […]

The post 2026 will be the year of space nuclear power and surviving the lunar night appeared first on SpaceNews.

Anyon physics could explain coexistence of superconductivity and magnetism

13 janvier 2026 à 09:45

New calculations by physicists in the US provide deeper insights into an exotic material in which superconductivity and magnetism can coexist. Using a specialized effective field theory, Zhengyan Shi and Todadri Senthil at the Massachusetts Institute of Technology show how this coexistence can emerge from the collective states of mobile anyons in certain 2D materials.

An anyon is a quasiparticle with statistical properties that lie somewhere between those of bosons and fermions. First observed in 2D electron gases in strong magnetic fields, anyons are known for their fractional electrical charge and fractional exchange statistics, which alter the quantum state of two identical anyons when they are exchanged for each other.

Unlike ordinary electrons, anyons produced in these early experiments could not move freely, preventing them from forming complex collective states. Yet in 2023, experiments with a twisted bilayer of molybdenum ditelluride provided the first evidence for mobile anyons through observations of fractional quantum anomalous Hall (FQAH) insulators. This effect appears as fractionally quantized electrical resistance in 2D electron systems at zero applied magnetic field.

Remarkably, these experiments revealed that molybdenum ditelluride can exhibit superconductivity and magnetism at the same time. Since superconductivity usually relies on electron pairing that can be disrupted by magnetism, this coexistence was previously thought impossible.

Anyonic quantum matter

“This then raises a new set of theoretical questions,” explains Shi. “What happens when a large number of mobile anyons are assembled together? What kind of novel ‘anyonic quantum matter’ can emerge?”

In their study, Shi and Senthil explored these questions using a new effective field theory for an FQAH insulator. Effective field theories are widely used in physics to approximate complex phenomena without modelling every microscopic detail. In this case, the duo’s model captured the competition between anyon mobility, interactions, and fractional exchange statistics in a many-body system of mobile anyons.

To test their model, the researchers considered the doping of an FQAH insulator – adding mobile anyons beyond the plateau in Hall resistance, where the existing anyons were effectively locked in place. This allowed the quasiparticles to move freely and form new collective phases.

“Crucially, we recognized that the fate of the doped state depends on the energetic hierarchy of different types of anyons,” Shi explains. “This observation allowed us to develop a powerful heuristic for predicting whether the doped state becomes a superconductor without any detailed calculations.”

In their model, Shi and Senthil focused on a specific FQAH insulator called a Jain state, which hosts two types of anyon excitations. One type has electrical charge of 1/3 of an electron and the other with 2/3. In a perfectly clean system, doping the insulator with 2/3-charge anyons produced a chiral topological superconductor, a phase that is robust against disorder and features edge currents flowing in only one direction. In contrast, doping with 1/3-charge anyons produced a metal with broken translation symmetry – still conducting, but with non-uniform patterns in its electron density.

Anomalous vortex glass

“In the presence of impurities, we showed that the chiral superconductor near the superconductor–insulator transition is a novel phase of matter dubbed the ‘anomalous vortex glass’, in which patches of swirling supercurrents are sprinkled randomly across the sample,” Shi describes. “Observing this vortex glass phase would be smoking-gun evidence for the anyonic mechanism for superconductivity.”

The results suggest that even when adding the simplest kind of anyons – like those in the Jain state – the collective behaviour of these quasiparticles can enable the coexistence of magnetism and superconductivity. In future studies, the duo hopes that more advanced methods for introducing mobile anyons could reveal even more exotic phases.

“Remarkably, our theory provides a qualitative account of the phase diagram of a particular 2D material (twisted molybdenum ditelluride), although many more tests are needed to rule out other possible explanations,” Shi says. “Overall, these findings highlight the vast potential of anyonic quantum matter, suggesting a fertile ground for future discoveries.”

The research is described in PNAS.

The post Anyon physics could explain coexistence of superconductivity and magnetism appeared first on Physics World.

Reçu — 12 janvier 2026 6.5 📰 Sciences English
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