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The CERN Accelerator School celebrates 40 years

The CERN Accelerator School (CAS) celebrated its 40th anniversary in the sunshine last September and with its contributors this January.

Back in the 1980s, a group of CERN scientists and engineers saw the need for an educational training programme in the rapidly evolving field of accelerator physics and technology. Textbooks on accelerator physics were sparse at the time, and courses at universities were practically non-existent. As Herwig Schopper, then CERN Director-General, put it: “An enormous amount of expertise is stored in the brains of quite a number of people […]. However, very little of this knowledge has so far been documented or published in book form.” It was into this landscape that the CERN Accelerator School was born in 1983.

The success of CAS in Europe quickly caught the attention of the global accelerator community, leading to a surge in demand for its courses. To accommodate this growing interest, CAS began organising courses outside Europe, in Asia and the Americas, from 1985, in collaboration with other institutions and organisations working in accelerator physics.

Over its 40-year-long history, more than 6000 participants from across the globe have been trained.

Find out more about the history, impact and future of the CERN Accelerator School in the latest CERN Courier: https://cerncourier.com/a/40-years-of-accelerating-knowledge/

anschaef Wed, 01/31/2024 - 11:32 Byline CERN Accelerator School Publication Date Wed, 01/31/2024 - 11:29

Accessible by design: how CERN Science Gateway exhibitions are tailored to people with visual impairments A visitor from ABA testing the Discover CERN: Accelerate exhibition with her guide. (Image: CERN)

Since opening in October, CERN Science Gateway has welcomed almost 100 000 visitors. Among these was a group of around 50 people from the Association pour le Bien des Aveugles et malvoyants (ABA), the reference association in Geneva for blind and visually impaired people, who toured the exhibitions on 28 November. ABA has worked with the CERN exhibitions team since 2019 and this was the chance for its members, including some visually impaired members, to see the fruit of this collaboration.

At the event, Emma Sanders, head of the CERN exhibitions team, and Bernard Jost, ABA’s accessibility project manager, explained how they had developed the exhibitions with accessibility and inclusivity at the forefront.

“We learnt very early on that making content more accessible usually benefits more than one kind of audience group,” Emma explained. “Tactile content is great for people who are blind or who have visual impairments, but it is also appreciated by many children. Wheel-chair accessible furniture is also good for parents pushing kids in buggies.”

“The idea came from CERN,” says Jost. “While the law requires cultural sites in Geneva to be as accessible as possible, what’s praiseworthy about CERN Science Gateway is that they made a point of taking accessibility into account from the beginning. We haven't created a parallel accessible exhibition: it's the same exhibition with some additional accessible features.”

The exhibition Our Universe: Back to the Big Bang features a tactile timeline of the Universe. (Image: CERN)

The permanent Science Gateway exhibitions comprise three parts: Discover CERN, Our Universe and Quantum World. Many installations incorporate an audio description and many also include tactile features, where visitors can touch and explore to interpret the content for themselves.

“One of the exhibitions that impressed me the most was Discover CERN, where I was able to go around the tunnel that the particles pass through and, thanks to the guide's description, experience the entire journey they take. It was impressive,” says Anne Gaugaz, one of the ABA visitors with visual impairments. “I also liked, in Back to the Big Bang, being able to touch the planets of the solar system that were in relief. That helped me to understand how big they were.”

A visitor from ABA touring the ​​​​Discover CERN: Collide exhibition with his guide and guide dog. (Image: CERN)

“Thanks to the guided tour, I enjoyed my visit to the Science Gateway exhibitions, in particular the accelerator exhibition and the part that takes us back in time to the Big Bang. It was very interesting and informative,” says Bertram Paul, a blind member of the ABA group who also worked with the exhibitions team to advise on the audio descriptions.

While the visit in November was a success, there is still work to be done. “Of course, it’s an evolving process,” Jost continues. “Some more alterations need to be made, so we will keep in touch.”

Content designed for people with visual impairments is just one aspect of Science Gateway’s effort to be accessible to all. And to complement the exhibitions, there is now a new CERN guides course focusing on accessibility, which is run by another local group, Culture Accessible. Visit this link to find out how you can become a Science Gateway guide.

For colleagues across CERN who are interested in making their work more accessible, the exhibitions team can share more about the process. As Emma recommends, “It’s always easier to ensure accessibility when you build it in from the start of your project. Working together with the community is essential: it brings creative and sometimes unexpected solutions that often work better for everyone.”

ndinmore Wed, 01/31/2024 - 09:43 Byline Naomi Dinmore Publication Date Wed, 01/31/2024 - 09:33

Nature Physics, Published online: 31 January 2024; doi:10.1038/s41567-024-02397-0

Multiple mechanisms can create electrons with reduced kinetic energy in solids. Combining these mechanisms now appears as a promising route to enhancing quantum effects in flat band materials.

Nature Physics, Published online: 31 January 2024; doi:10.1038/s41567-024-02386-3

Magnons—quanta of spin waves—have potential applications in signal processing technology. But it is challenging to obtain coupling between different magnons. Now a study achieves this by demonstrating nonlinear magnon mixing in an antiferromagnet.

Nature Physics, Published online: 31 January 2024; doi:10.1038/s41567-023-02374-z

The electronic transport properties of charge-ordered kagome metals are controversial. Now careful measurements on unperturbed samples show that previously measured anisotropy in the transport occurs only when external perturbations are present.

Computer Security: 300 computer security articles and counting

We begin the year by celebrating the 300th Bulletin article focusing on various computer-security-related topics. Three hundred hopefully informative articles about the cybersecurity situation at CERN. About best practices, guidelines and useful tools. About risks, threat scenarios and attack vectors. About new or established means of mitigation. About the workings of the Computer Security team, the services and tools it’s providing and the complexity of its detection infrastructure. About policies and dos and don’ts. Three hundred articles trying to raise your awareness and help you improve your approach to computer security – the security of your laptops, smartphones and tablets, of your accounts and passwords, of your email inbox and web browser, of software programming and system development – both at CERN and at home.

While some articles were published a long time ago – the first ones were released in 2008 – they’ve never lost their relevance. Sometimes it’s useful to delve into the past and dig out information from them; often these articles also provide guidelines for us when advising users. So for this 300th anniversary, we have updated our compilation of all the articles published so far. This compilation covers a plethora of topics, sorted into the notorious themes of “computer security”, i.e. the literal cybersecurity of computers, “mobile and cloud security”, “network and data centre security”, “account and password security”, “control systems and IoT (Internet of Things)”, “secure software development”, “data protection and privacy”, “copyrights”, “rules and policies” and more. Giving a deeper insight into the computer security landscape, these articles complement our Monthly Reports, which usually depict the operational side of what’s currently happening at CERN.

You can download this compilation here. It’s public – published under CC-BY-NC-SA. So please feel free to share it with your colleagues, family and friends in order to spread the word, raise awareness and help them improve the security and protection of their own digital assets and resources!

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Do you want to learn more about computer security incidents and issues at CERN? Follow our Monthly Report. For further information, questions or help, check our website or contact us at Computer.Security@cern.ch.

anschaef Tue, 01/30/2024 - 11:03 Byline Computer Security team Publication Date Tue, 01/30/2024 - 11:00

Nature Physics, Published online: 30 January 2024; doi:10.1038/s41567-023-02288-w

Phonons do not carry spin or charge, but they can couple to an external magnetic field and cause a sizable transverse thermal gradient. Experiments suggest that phonon handedness is a widespread effect in magnetic insulators with impurities.

Nature Physics, Published online: 30 January 2024; doi:10.1038/s41567-024-02384-5

The thermal Hall effect of phonons does not yet have a definitive explanation. Now a careful study of doped Sr2IrO4 suggests that the mechanism involves the scattering of phonons by impurities embedded in an antiferromagnetic environment.

Nature Physics, Published online: 30 January 2024; doi:10.1038/s41567-024-02385-4

Heterostructures of transition metal dichalcogenides are known to simulate the triangular-lattice Hubbard model. Now, by combining a monolayer and bilayer of different materials, this idea is extended to multi-orbital Hubbard models.

Nature Physics, Published online: 29 January 2024; doi:10.1038/s41567-023-02365-0

Understanding the three-dimensional nature of fracture formation and dynamics is challenging. Experiments now show that a fracture front, after originating at a particular locus in a material, propagates jump-wise and expands transversely at high speed.

Nature Physics, Published online: 26 January 2024; doi:10.1038/s41567-023-02382-z

Electronic transport measurements of the anomalous Hall effect can probe properties of a frustrated kagome spin ice that are hidden from conventional thermodynamic and magnetic probes.

Nature Physics, Published online: 26 January 2024; doi:10.1038/s41567-023-02366-z

Physical ageing in glassy materials can be described in a linear way through the concept of material time. Multispeckle dynamic light scattering is now shown to provide experimental access to the material time, in terms of which fluctuations become statistically reversible.

Nature Physics, Published online: 26 January 2024; doi:10.1038/s41567-023-02378-9

Most quantum simulations of spin models with trapped ions have been restricted to one dimension. Now, tunable simulations of Ising models with single-site detection have been demonstrated in two-dimensional ion crystals.

Nature Physics, Published online: 26 January 2024; doi:10.1038/s41567-023-02362-3

Observations of strong electron correlation effects have been mostly confined to compounds containing f orbital electrons. Now, the study of the 3d pyrochlore metal CuV2S4 reveals that similar effects can be induced by flat-band engineering.

Nature Physics, Published online: 25 January 2024; doi:10.1038/s41567-023-02375-y

Experiments with unprecedented energy and momentum resolution reveal the nature of the pairing symmetry in KFe2As2 and pave the way for a unified theoretical description of unconventional superconductivity in iron-based materials.

Nature Physics, Published online: 25 January 2024; doi:10.1038/s41567-023-02372-1

Cytoplasmic flows in the fruit fly oocyte can reorganize cellular components. These structured vortical flows arise through self-organizing dynamics of microtubules, molecular motors and cytoplasm.

Nature Physics, Published online: 25 January 2024; doi:10.1038/s41567-023-02358-z

Control over magnetic skyrmions at room temperature has important applications in technology. Now the observation of skyrmions with high topological charge widens the potential for them to be used in unconventional computing techniques.

Nature Physics, Published online: 25 January 2024; doi:10.1038/s41567-023-02377-w

Quantum gates require controlled interactions between different degrees of freedom. A tunable coupling has now been demonstrated between the phonon modes of a mechanical resonator designed for storing and manipulating quantum information.

Nature Physics, Published online: 25 January 2024; doi:10.1038/s41567-023-02360-5

Electrons in f orbitals can create localized states that interact strongly and drive strange metal and critical behaviour via the Kondo mechanism. Now a mechanism of geometric frustration enables similar phenomena with d electrons.

Nature Physics, Published online: 24 January 2024; doi:10.1038/s41567-023-02352-5

Studies of a biological active nematic fluid reveal a spontaneous self-constraint that arises between self-motile topological defects and mesoscale coherent flow structures. The defects follow specific contours of the flow field, on which vorticity and strain rate balance, and hence, contrary to expectation, they break mirror symmetry.