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Researchers from the University of Twente in the Netherlands have gained important insights into photons, the elementary particles that make up light. They ‘behave’ in an amazingly greater variety than electrons surrounding atoms, while also being much easier to control.

These new insights have broad applications from smart LED lighting to new photonic bits of information controlled with , to sensitive nanosensors. Their results are published in Physical Review B.

In atoms, minuscule elementary particles called electrons occupy regions around the nucleus in shapes called orbitals. These orbitals give the probability of finding an electron in a particular region of space. Quantum mechanics determines the shape and energy of these orbitals. Similarly to electrons, researchers describe the region of space where a is most likely found with orbitals too.

In 1968, deep underground in the Homestake gold mine in South Dakota, Ray Davis Jr.


At the same time, Steven Weinberg and Abdus Salam were carrying out major construction work on what would become the Standard Model of particle physics, building the Higgs mechanism into Sheldon Glashow’s unification of the electromagnetic and weak interactions. The Standard Model is still bulletproof today, with one proven exception: the nonzero neutrino masses for which Davis’s observations were in hindsight the first experimental evidence.

Today, neutrinos are still one of the most promising windows into physics beyond the Standard Model, with the potential to impact many open questions in fundamental science ( CERN Courier May/June 2024 p29). One of the most ambitious experiments to study them is currently taking shape in the same gold mine as Davis’s experiment more than half a century before.

In February this year, the international Deep Underground Neutrino Experiment (DUNE) completed the excavation of three enormous caverns 1.5 kilometres below the surface at the new Sanford Underground Research Facility (SURF) in the Homestake mine. 800,000 tonnes of rock have been excavated over two years to reveal an underground campus the size of eight soccer fields, ready to house four 17,500 tonne liquid–argon time-projection chambers (LArTPCs). As part of a diverse scientific programme, the new experiment will tightly constrain the working model of three massive neutrinos, and possibly even disprove it.

New research introduces a non-thermal method for magnetization using circularly polarized XUV light, which induces significant magnetization changes through the inverse Faraday effect, potentially transforming ultrafast data storage and spintronics.

Intense laser pulses can be used to manipulate or even switch the magnetization orientation of a material on extremely short time scales. Typically, such effects are thermally induced, as the absorbed laser energy heats up the material very rapidly, causing an ultrafast perturbation of the magnetic order.

Scientists from the Max Born Institute (MBI), in collaboration with an international team of researchers, have now demonstrated an effective non-thermal approach of generating large magnetization changes. By exposing a ferrimagnetic iron-gadolinium alloy to circularly polarized pulses of extreme ultraviolet (XUV) radiation, they could reveal a particularly strong magnetic response depending on the handedness of the incoming XUV light burst (left-or right-circular polarization).

The ionization energy is the amount of energy required to remove a single electron from an atom. If the atom has more than one electron, each one requires more energy than the previous one. The result is a series of increasing energy levels, and in the quantum world these energies correspond to frequencies, as in a musical scale.

This raises an interesting question: if we could hear these frequencies how would they sound? I created an app to find out, and in this video I used my app to share what I learned. As it turns out, the results are quite musical.

Important note: This audio includes some very low frequencies, which you might not hear through typical cell phone or laptop speakers. I recommend listening with headphones or a high-quality playback system.

The app was created using the APL programming language.

One of the key metrics for climate modeling is radiative forcing. Most climate models, including the general circulation models (GCMs), focus on the effects of different atmospheric factors on radiative forcing. However, there are still large uncertainties in satellite observations and multi-model simulations associated with some atmospheric factors.

Among them, clouds are a known source of uncertainty in GCMs, leading to radiative biases. However, another possible source of radiative uncertainty is associated with .

In principle, precipitating particles affect by disrupting incoming shortwave and outgoing longwave radiations. But most conventional GCMs in the Coupled Model Intercomparison Project Phase 6 (CMIP6) treat precipitation diagnostically and exclude the radiative effects of precipitation (REP). Extracting the magnitude of REP in climate models is challenging because of complicated atmosphere-ocean feedback and multi-model variabilities.

How can we advance cutting-edge research but consume less energy? CERN’s scientists are working on innovative solutions, and superconductivity is one of the key ingredients.

A team has recently successfully tested a demonstrator magnet coil that will significantly reduce the power consumption of certain experiments. The coil is made of magnesium diboride (MgB2) , which are used in the high-intensity electrical transfer line that will power the High-Luminosity LHC (HL-LHC), the successor to the LHC. It is mounted in a low-carbon steel magnetic yoke that holds and concentrates the field lines, in a so-called superferric configuration.

This innovative magnet is intended for the SHiP experiment, which is designed to detect very weakly interacting particles and is scheduled to be commissioned in 2031. One of the detector’s two magnets must produce a field of approximately 0.5 tesla. The field is of moderate intensity but must be produced in a huge volume that is 6 meters high and 4 meters wide and deep. A normal-conducting resistive electromagnet would have an electrical power of over one megawatt and, as it would have to operate continuously, its power consumption would be high.

New research indicates that plasma fusion heat spreads more evenly in tokamak reactors, suggesting a reduced risk of damage to critical components, thereby improving reactor longevity and efficiency.

According to researchers from the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL), Oak Ridge National Laboratory, and the ITER Organization (ITER), the intense exhaust heat produced by fusing plasma in a commercial-scale reactor might not be as damaging to the reactor’s interior as previously believed.

“This discovery fundamentally changes how we think about the way heat and particles travel between two critically important regions at the edge of a plasma during fusion,” said PPPL Managing Principal Research Physicist Choongseok Chang, who led the team of researchers behind the discovery. A new paper detailing their work was recently published in the journal Nuclear Fusion, following previous publications on the subject.