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World Wide Web at 35 Tim Berners-Lee invented and developed the World Wide Web as an essential tool for high energy physics at CERN from 1989 to 1994. Together with a small team he conceived HTML, http, URLs, and put up the first server and the first 'what you see is what you get' browser and html editor. (Image: CERN)

Thirty-five years ago, a young computer expert working at CERN wrote a proposal that combined accessing information with a desire for broad connectivity and openness. This proposal went on to become the World Wide Web (WWW), whose impact on society has been profound.  

Sir Tim Berners-Lee’s first proposal in March 1989 was for an internet-based hypertext system to link and access information across different computers. In November 1990, this “web of information nodes in which the user can browse at will” was formalised as a proposal, “WorldWideWeb: Proposal for a HyperText Project”, by Berners-Lee, together with a CERN colleague, Robert Cailliau. By Christmas that year, Berners-Lee had implemented key components, namely html, http and URL, and created the first Web server, browser and editor (WorldWideWeb). This server is now exhibited in the Laboratory’s new visitor centre, CERN Science Gateway.

CERN released the WWW software into the public domain on 30 April 1993, making it freely available for anyone to use and improve. This decision encouraged the use of the Web, and society to benefit from it.

Now, thirty-five years since his original proposal, Sir Tim Berners-Lee reflects on the web’s trajectory in an open letter and states how we, as engaged citizens, can "re-shape a digital future that prioritises human well-being, equity, and autonomy".

katebrad Mon, 03/25/2024 - 15:36 Publication Date Wed, 03/27/2024 - 16:24

Brazil becomes Associate Member State of CERN

Brazil has become the first Associate Member State of CERN in the Americas, following official notification that the country has completed its internal approval procedures in respect of the agreement signed in March 2022 granting it that status and of the Protocol on Privileges and Immunities of the Organization. The starting date of Brazil’s status as an Associate Member State is 13 March 2024.

Formal cooperation between CERN and Brazil started in 1990 with the signature of an International Cooperation Agreement, allowing Brazilian researchers to participate in the DELPHI experiment at the Large Electron–Positron Collider (LEP). Over the past decade, Brazil’s experimental particle-physics community has doubled in size. At the four main Large Hadron Collider (LHC) experiments alone, about 200 Brazilian scientists, engineers and students collaborate in fields ranging from hardware and data processing to physics analysis.

Today, Brazilian institutes participate in all the main experiments at the LHC – ALICE, ATLAS, CMS and LHCb and their ongoing and planned upgrades – as well as in ALPHA at the anti-proton decelerator. They are also involved in experiments at ISOLDE, ProtoDUNE at the Neutrino Platform and instrumentation projects such as Medipix. Following on from their participation in the RD51 collaboration, Brazilian teams are also contributing to setting up the DRD1 and DRD3 R&D collaborations for future detectors. Brazilian nationals also participate very actively in CERN training and outreach programmes.

Beyond particle physics, CERN and Brazil’s National Centre for Research in Energy and Materials (CNPEM) have also been formally cooperating since December 2020 on accelerator technology R&D and its applications.

As an Associate Member State, Brazil is entitled to appoint representatives to attend meetings of the CERN Council and the Finance Committee. Its nationals are eligible to apply for limited-duration staff positions and CERN’s graduate programmes, and its industry is entitled to bid for CERN contracts, increasing opportunities for industrial collaboration in advanced technologies.

angerard Fri, 03/22/2024 - 09:06 Publication Date Fri, 03/22/2024 - 17:00

Nature Physics, Published online: 22 March 2024; doi:10.1038/s41567-024-02435-x

Experiments probing three-dimensional crack propagation show that the critical strain energy needed to drive a crack is directly proportional to its geodesic length. This insight is a step towards a fully three-dimensional theory of crack propagation.

CERN rewarded for its contributions to cloud computing

On 21 March, CERN received the “Top End User” special award by the Cloud Native Computing Foundation (CNCF) for its “forward-looking approach to leveraging cloud native technologies to address future scientific and operational challenges”. Prior recipients of the “Top End User” CNCF award have included Mercedes-Benz, Spotify and Apple.  

Cloud native technologies are software solutions that exploit the basic features of cloud computing – e.g., scalability, flexibility, data resiliency – and allow system engineers to effectively manage complex computing environments with minimal effort. CERN has been a member of the CNCF community since 2020 and is considered an “end user” because it develops cloud native technologies internally but does not sell cloud service externally.

CERN contributes to community-driven cloud computing ecosystems, such as the CNCF, but also runs its own private cloud, which is configured and integrated into the CERN network and authentication services. The organization’s cloud ecosystem is heterogeneous and complex, as Taylor Dolezal, head of ecosystem at CNCF confirmed: “CERN's innovative use of cloud native technologies is a shining example of how open source and collaboration can drive cutting-edge research.”

For more details see the CNCF announcement and the IT README.

katebrad Thu, 03/21/2024 - 16:12 Publication Date Thu, 03/21/2024 - 15:39

Scientists use n_TOF to investigate how cerium is produced in the Universe The experimental setup. (Image: n_TOF collaboration)

Cerium is a rare Earth metal that has numerous technological applications, for example in some types of lightbulbs and flat-screen TVs. While the element is rare in Earth’s crust, it is slightly more abundant in the Universe. However, much is unknown about how it is synthesised in stars. Now, in a new study published in Physical Review Letters, the n_TOF collaboration at CERN investigates how cerium is produced in stars. The results differ from what was expected from theory, indicating a need to review the mechanisms believed to be responsible for the production of cerium – and other heavier elements – in the Universe.

“The measurement we carried out enabled us to identify nuclear resonances never observed before in the energy range involved in the production of cerium in stars,” explains Simone Amaducci, of INFN’s Southern National Laboratories and first author of the study. “This is thanks to the very-high-energy resolution of the experimental apparatus at CERN and the availability of a very pure sample of cerium 140.”

The abundance of elements heavier than iron observed in stars (such as tin, silver, gold and lead) can be reproduced mathematically by hypothesising the existence of two neutron capture processes: the slow (s) process and the rapid (r) process. The s process corresponds to a neutron flux of 10 million neutrons per cubic centimetre while the r process has a flux of more than one million billion billion neutrons per cubic centimetre. The s process is theorised to produce about half of the elements heavier than iron in the Universe, including cerium.

CERN’s Neutron Time-of-Flight facility (n_TOF) is designed to study neutron interactions, such as those that occur in stars. In this study, the scientists used the facility to measure the nuclear reaction of the cerium 140 isotope with a neutron to produce isotope 141. According to sophisticated theoretical models, this particular reaction plays a crucial role in the synthesis of heavy elements in stars. Specifically, the scientists looked at the reaction’s cross section: the physical quantity that expresses the probability that a reaction occurs. The scientists measured the cross section at a wide range of energies with an accuracy 5% higher than previous measurements.

The results open up new questions about the chemical composition of the Universe. “What intrigued us at the beginning was a discrepancy between theoretical star models and observational data of cerium in the stars of the M22 globular cluster in the Sagittarius constellation,” explains Sergio Cristallo of INAF’s Abruzzo Astronomical Observatory, who proposed the experiment. “The new nuclear data differs significantly, up to 40%, from the data present in the nuclear databases currently used, definitely beyond the estimated uncertainty.”

These results have notable astrophysical implications, suggesting a 20% reduction in the contribution of the s process to the abundance of cerium in the Universe. This means a paradigm shift is required in the theory of cerium nucleosynthesis: other physical processes that are not currently included would need to be considered in calculations of stellar evolution. Furthermore, the new data has a significant impact on scientists’ understanding of the chemical evolution of galaxies, which also affects the production of heavier elements in the Universe.

ndinmore Thu, 03/21/2024 - 11:42 Publication Date Thu, 03/21/2024 - 17:06

CERN launches the White Rabbit Collaboration The White Rabbit community gathers to celebrate the launch of the White Rabbit Collaboration. (Image: CERN)

White Rabbit (WR) is a technology developed at CERN, in collaboration with institutes and companies, to synchronise devices in the accelerators down to sub-nanoseconds and solve the challenge of establishing a common notion of time across a network. Indeed, at a scale of billionths of a second, the time light takes to travel through a fibre-optic cable and the time the electronics take to process the signal are no longer negligible. To avoid potential delays, the co-inventors of White Rabbit designed a new ethernet switch.

First used in 2012, the application of this fully open-source technology has quickly expanded outside the field of particle physics. In 2020, it was included in the worldwide industry standard known as Precision Time Protocol (PTP), governed by the Institute of Electrical and Electronics Engineers (IEEE).

What’s more, CERN recently launched the White Rabbit Collaboration, a membership-based global community whose objective is to maintain a high-performance open-source technology that meets the needs of users and to facilitate its uptake by industry. The WR Collaboration will provide dedicated support and training, facilitate R&D projects between entities with common interests and complementary expertise and establish a testing ecosystem fostering trust in products that incorporate the open-source technology. At CERN, the WR Collaboration Bureau – a dedicated team composed of senior White Rabbit engineers and a community coordinator – will facilitate the day-to-day running of the Collaboration’s activities and support its members.

“A key distinctive feature of White Rabbit, as opposed to other technologies that have been developed since, is that it is open source and based on standards”, says Javier Serrano, Chair of the White Rabbit Collaboration Board and co-inventor of the technology. Companies and institutes can therefore adapt it to their needs and incorporate it in their products and systems, while the technology, in turn, benefits from a large community of developers. “The first step to foster industry uptake was to include WR concepts in the IEEE standard. Through this endeavour, we established many links with industry,” says Maciej Lipinski, Chair of the White Rabbit Collaboration Council and senior White Rabbit engineer at CERN.

White Rabbit is used in the finance sector as well as in many research infrastructures, and it is currently being evaluated for application in the future quantum internet. The technology could also play a key role in the future landscape of global time dissemination technologies, which currently rely heavily on satellites. The infrastructure for the dissemination of time is essential to the economy and underpins most critical national infrastructure. Governments and industry across the globe are therefore striving to find alternatives to distribute a reference time, such as the one WR could offer via optical fibre, with telecom and power grid companies starting to test WR in their networks.

The WR Collaboration comes at a moment when many sectors are undergoing a profound transformation with regards to their timing technology. “The WR Collaboration will provide a neutral gathering point around this open-source technology and define a long-term common vision, establishing a solid ground from which innovation can thrive,” continues Amanda Diez Fernandez from CERN’s Knowledge Transfer group and the White Rabbit Community Coordinator.

To learn more about how to join the White Rabbit Collaboration, go to: www.white-rabbit.tech

_______

From 21–22 March, the White Rabbit community met at CERN to celebrate the launch of the WR Collaboration. To find out more, listen to the recorded talks of the event.

ndinmore Thu, 03/21/2024 - 10:12 Publication Date Fri, 03/22/2024 - 14:10

Nature Physics, Published online: 20 March 2024; doi:10.1038/s41567-023-02344-5

Stable regions in four-dimensional phase space have been observed by following the motion of accelerated proton beams subject to nonlinear forces. This provides insights into the physics of dynamical systems and may lead to improved accelerator designs.

Nature Physics, Published online: 20 March 2024; doi:10.1038/s41567-023-02338-3

Nonlinear resonances can cause particle loss in accelerators. Experiments confirm that a coupled nonlinear resonance traps beam particles on a four-dimensional closed curve. This finding allows the development of mitigation strategies.

Nature Physics, Published online: 20 March 2024; doi:10.1038/s41567-024-02429-9

A mechanism for the phase transition of charge density wave states via the generation and proliferation of topological defects with opposite phase windings is demonstrated in a heavy-fermion superconductor.

Observing accelerator resonances in 4D CERN’s Super Proton Synchrotron in 2022. (Image: CERN)

Whether in listening to music or pushing a swing in the playground, we are all familiar with resonances and how they amplify an effect – a sound or a movement, for example. However, in high-intensity circular particle accelerators, resonances can be an inconvenience, causing particles to fly off their course and resulting in beam loss. Predicting how resonances and non-linear phenomena affect particle beams requires some very complex dynamics to be disentangled.

For the first time, scientists at the Super Proton Synchrotron (SPS), in collaboration with scientists at GSI in Darmstadt, have been able to experimentally prove the existence of a particular resonance structure. While it had previously been theorised and appeared in simulations, this structure is very difficult to study experimentally as it affects particles in a four dimensional space*. These latest results, published in Nature Physics, will help to improve the beam quality for low-energy and high-brightness beams for the LHC injectors at CERN and the SIS18/SIS100 facility at GSI, as well as for high-energy beams with large luminosity, such as the LHC and future high-energy colliders.

“With these resonances, what happens is that particles don’t follow exactly the path we want and then fly away and get lost,” says Giuliano Franchetti, a scientist at GSI and one of the paper’s authors. “This causes beam degradation and makes it difficult to reach the required beam parameters.”

The idea to look for the cause of this emerged in 2002, when scientists at GSI and CERN realised that particle losses increased as accelerators pushed for higher beam intensity. “The collaboration came from the need to understand what was limiting these machines so that we could deliver the beam performance and intensity needed for the future,” says Hannes Bartosik, a scientist at CERN and another of the paper’s authors.

Over many years, theories and simulations were developed to understand how resonances affected particle motion in high-intensity beams. “It required an enormous simulation effort by large accelerator teams to understand the effect of the resonances on beam stability,” says Frank Schmidt at CERN, also one of the paper’s authors. The simulations showed that resonance structures induced by coupling in two degrees of freedom are one of the main causes of beam degradation.

It took a long time to devise how to look for these resonance structures experimentally. This is because they are four dimensional* and require the beam to be measured in both the horizontal and the vertical planes to see if they exist. “In accelerator physics, the thinking is often in only one plane,” adds Franchetti.

Figure 1: Conceptually visualising 4D resonance structures is much more complicated than one-dimensional resonances. This image shows the 4D resonance structure measured in the SPS. (Image: H. Bartosik, G. Franchetti and F. Schmidt, Nature Physics)

To measure how resonances affect particle motion, the scientists used beam position monitors around the SPS. Over approximately 3000 beam passages, the monitors measured whether the particles in the beam were centred or more to one side, in both the horizontal and vertical planes. The resonance structure that was found is shown in Figure 1.

“What makes our recent finding so special is that it shows how individual particles behave in
a coupled resonance,” continues Bartosik. “We can demonstrate that the experimental findings agree with what had been predicted based on theory and simulation.”

While the existence of the coupled resonance structures has now been observed experimentally, much more remains to be done to reduce their detrimental effect. “We’re developing a theory to describe how particles move in the presence of these resonances,” continues Franchetti. “With this study, coupled with all the previous ones, we hope we will get clues on how to avoid or minimise the effects of these resonances for current and future accelerators.”

*Space refers to “phase space” – the space in which all possible states of a system are represented

Read the paper here

ndinmore Tue, 03/19/2024 - 12:09 Byline Naomi Dinmore Publication Date Wed, 03/20/2024 - 11:15

CERN publishes knowledge transfer highlights from 2023 CERN’s 2023 knowledge transfer highlights are available for the first time in digital format, in line with CERN’s commitment to reduce unnecessary printing. (Image: CERN)

CERN’s new digital report “Accelerating Innovation Through Partnerships” highlights knowledge transfer activities from 2023. It showcases concrete applications of CERN technologies and know-how, with diverse examples in the healthcare, environment, aerospace, digital and quantum fields.

Find out more about CERN’s ongoing partnerships with industry, academia, research institutions and hospitals in its Member and Associate Member States. See how entrepreneurs are supported by the recently launched CERN Venture Connect programme. Discover how these activities not only drive innovation but also have a positive impact on society.

Save the date of 18 April 2024 for the public event “The virtuous circle of knowledge and innovation” taking place in CERN Science Gateway as part of the series of events for CERN’s 70th birthday.

For more information about CERN’s ongoing knowledge transfer activities, visit kt.cern.

This video summarises the new digital report “Accelerating Innovation Through Partnerships”. (Video: CERN) katebrad Tue, 03/19/2024 - 11:53 Byline CERN Knowledge Transfer group Publication Date Wed, 03/20/2024 - 14:01

Nature Physics, Published online: 18 March 2024; doi:10.1038/s41567-024-02439-7

Exploring and exploiting electric dipole arrangements analogously to what is possible with magnetic spin textures is an emerging prospect. Now a spontaneous toroidal polar topology is observed in ferroelectric liquid crystals.

Accelerator Report: Beams are circulating in the LHC The LHC fixed display, just after both beams entered into circulation. The blue and red lines represent the number of protons in beams 1 and 2, respectively. The black line represents the energy of the beams. It is flat because the beams had not yet been accelerated at this point. (Image: CERN)

On 8 March, three days ahead of schedule, the first proton beam was injected into the LHC; 20 minutes later, the second beam was injected, circulating in the opposite direction.

Since the last Accelerator Report, the hardware tests and subsequent cold check-out were successfully completed, both ahead of schedule. Once the usual remaining wrinkles were ironed out, everything was ready to start the 2024 LHC beam commissioning. The single bunch low intensity probe beam, meticulously prepared in the injector chain in the past weeks, came knocking at the LHC's door.

Many of the LHC engineers in charge and system experts gathered in the CERN Control Centre (CCC) on 8 March, alongside members of the Management, to witness the process, eagerly waiting for the first beams to circulate again in the LHC.

The LHC Operations team started the injection and threading process for beam 2 (circulating counter clockwise): they injected the beam at LHC Point 8, just in front of the LHCb experiment, and let it circulate up to Point 7, where a set of collimators was fully closed to intercept it. The measurements performed by the beam position monitors indicated that the beam trajectory could be improved. This was quickly done using an automated beam steering tool that powers corrector magnets to smoothen the trajectories of the particles.

Confident in this correction, the Operations team opened up the collimators at Point 7 and closed the ones further along the ring at Point 6, before injecting the beam again. This process was repeated until the last collimators, at Point 1 (ATLAS experiment), were opened, leaving the way clear for the beam to make a second, third, fourth… and millionth turn.

Another small correction to adjust the orbit of the circulating particles was made before attention switched to beam 1, which ended up circulating in the machine less than 20 minutes after beam 2 and was welcomed by many happy faces in the CCC. The next step – accelerating both beams up to 6.8 TeV – was also accomplished during the weekend. Witnessing both beams in circulation is something of a relief for everyone involved, although the real beam commissioning work starts at that point.

For the 2024 run, it was decided to modify the optics of the accelerator and to replace them by reverse polarity optics (RP-optics). The objective is to mitigate the radiation suffered by some of the magnets of the inner triplet region on both sides of the ATLAS experiment. The inner triplet is a set of quadrupole magnets that focus the beam to very small dimensions at the centre of the experiments.

Some of the collision debris – particles produced by the collisions and travelling  parallel to the beams, outside the experiment – is intercepted by the magnets in the inner triplet regions, inducing radiation damage to their insulation. With different optics, the debris is deposited in other places in these magnets, so that the burden of the radiation damage is distributed more widely. This helps to extend the magnets' lifetimes, even with an increased number of collisions.

The commissioning and validation of the RP-optics are among the many beam commissioning steps that have to be taken in the coming weeks before beams enter into collision at 6.8 TeV, hopefully on 8 April. Depending on how work progresses, this milestone may shift forwards or backwards by a few days.

anschaef Thu, 03/14/2024 - 10:43 Byline Rende Steerenberg Publication Date Thu, 03/14/2024 - 10:39

Accelerator Report: Beams are circulating in the LHC The LHC fixed display, just after both beams entered into circulation. The blue and red lines represent the number of protons in beams 1 and 2, respectively. The black line represents the energy of the beams. It is flat because the beams had not yet been accelerated at this point. (Image: CERN)

On 8 March, three days ahead of schedule, the first proton beam was injected into the LHC; 20 minutes later, the second beam was injected, circulating in the opposite direction.

Since the last Accelerator Report, the hardware tests and subsequent cold check-out were successfully completed, both ahead of schedule. Once the usual remaining wrinkles were ironed out, everything was ready to start the 2024 LHC beam commissioning. The single bunch low intensity probe beam, meticulously prepared in the injector chain in the past weeks, came knocking at the LHC's door.

Many of the LHC engineers in charge and system experts gathered in the CERN Control Centre (CCC) on 8 March, alongside members of the Management, to witness the process, eagerly waiting for the first beams to circulate again in the LHC.

The LHC Operations team started the injection and threading process for beam 2 (circulating counter clockwise): they injected the beam at LHC Point 8, just in front of the LHCb experiment, and let it circulate up to Point 7, where a set of collimators was fully closed to intercept it. The measurements performed by the beam position monitors indicated that the beam trajectory could be improved. This was quickly done using an automated beam steering tool that powers corrector magnets to smoothen the trajectories of the particles.

Confident in this correction, the Operations team opened up the collimators at Point 7 and closed the ones further along the ring at Point 6, before injecting the beam again. This process was repeated until the last collimators, at Point 1 (ATLAS experiment), were opened, leaving the way clear for the beam to make a second, third, fourth… and millionth turn.

Another small correction to adjust the orbit of the circulating particles was made before attention switched to beam 1, which ended up circulating in the machine less than 20 minutes after beam 2 and was welcomed by many happy faces in the CCC. The next step – accelerating both beams up to 6.8 TeV – was also accomplished during the weekend. Witnessing both beams in circulation is something of a relief for everyone involved, although the real beam commissioning work starts at that point.

For the 2024 run, it was decided to modify the optics of the accelerator and to replace them by reverse polarity optics (RP-optics). The objective is to mitigate the radiation suffered by some of the magnets of the inner triplet region on both sides of the ATLAS experiment. The inner triplet is a set of quadrupole magnets that focus the beam to very small dimensions at the centre of the experiments.

Some of the collision debris – particles produced by the collisions and travelling  parallel to the beams, outside the experiment – is intercepted by the magnets in the inner triplet regions, inducing radiation damage to their insulation. With different optics, the debris is deposited in other places in these magnets, so that the burden of the radiation damage is distributed more widely. This helps to extend the magnets' lifetimes, even with an increased number of collisions.

The commissioning and validation of the RP-optics are among the many beam commissioning steps that have to be taken in the coming weeks before beams enter into collision at 6.8 TeV, hopefully on 8 April. Depending on how work progresses, this milestone may shift forwards or backwards by a few days.

anschaef Thu, 03/14/2024 - 10:43 Byline Rende Steerenberg Publication Date Thu, 03/14/2024 - 10:39

Nature Physics, Published online: 14 March 2024; doi:10.1038/s41567-024-02450-y

Fruity blues

Nature Physics, Published online: 14 March 2024; doi:10.1038/s41567-024-02449-5

Batter quality

Nature Physics, Published online: 14 March 2024; doi:10.1038/s41567-024-02428-w

Measuring air temperature is far from a trivial task, as Andrea Merlone, Graziano Coppa and Chiara Musacchio explain.

Nature Physics, Published online: 14 March 2024; doi:10.1038/s41567-024-02430-2

Honesty is being put through the mill

Nature Physics, Published online: 14 March 2024; doi:10.1038/s41567-023-02371-2

Computing is central to the enterprise of physics but few undergraduate physics courses include it in their curricula. Here we discuss why and how to integrate computing into physics education.

Nature Physics, Published online: 14 March 2024; doi:10.1038/s41567-024-02424-0

Injustices and oppression are pervasive in society, including education. An intersectional, equity-oriented approach can help remove systemic obstacles and improve the experience of marginalized people in physics education through decolonial and critical race lenses.