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Small version of a CERN detector could deliver more precise radiotherapy of head tumours

Wed, 06/03/2024 - 10:01
Small version of a CERN detector could deliver more precise radiotherapy of head tumours Mária Martišíková (left), the project leader from Heidelberg University Hospital and German Cancer Research Center (DKFZ), and DKFZ researcher Laurent Kelleter. (Image: Heidelberg University Hospital / H.Schroeder).

Particle detectors like the ones used by physicists at CERN can have wide applications beyond fundamental research. Scientists from the German National Center for Tumor Diseases (NCT), the German Cancer Research Center (DKFZ), and the Heidelberg Ion Beam Therapy Center (HIT) at Heidelberg University Hospital are now testing a new imaging device supplied by the Czech company ADVACAM on its first patients. The device, which includes a small Timepix3 pixel detector developed at CERN, allows head and neck tumours to be closely monitored during ion radiotherapy, making them easier to target and thus helping limit the treatment’s side effects.

"One of the most advanced methods for treating head and neck tumours involves irradiation with ion beams. This has one unique feature: it can be precisely tailored to the depth inside the human head where the particles should have the maximal effect”, explains Mária Martišíková, the head of the DKFZ team.

Yet like other types of irradiation, ion radiation also has a drawback. The particle beams affect not only the tumour but also part of the healthy tissue around it. This is particularly challenging in the brain, where damage to the optic nerve or a patient’s memory are possible. Ideally, the irradiated area around the tumour should be as small as possible, and the dose to the tumour should be as high as possible. However, current technology does not allow for sufficiently precise targeting of the ions.

To complicate matters further, the situation inside a patient's head can change during therapy. The x-ray computed tomography (CT) scan image taken before treatment is essentially used as a "map" to target the tumour with ion beams. But during therapy, the situation inside the skull may evolve. Until now, physicians lacked a reliable tool to alert them in case of a change in the brain.

The new ADVACAM device could help solve these issues, by improving the navigation of the ion beams inside the head by tracking the secondary particles that are created when ions pass through it.

"Our cameras can register every charged particle of secondary radiation emitted from the patient's body. It's like watching balls scattered by a billiard shot. If the balls bounce as expected according to the CT image, we can be sure we are targeting correctly. Otherwise, it's clear that the 'map' no longer applies. Then it is necessary to replan the treatment," describes Lukáš Marek from ADVACAM.

"We hope the new device will show us how often and where the tumour changes occur. It will allow us to reduce the overall irradiated volume of tissue, saving healthy tissue and reducing the side effects of radiotherapy. We will also be able to apply higher doses of radiation to the tumour" adds Martišíková.

The treatment can benefit enormously from the additional information obtained from the camera. In the first phase, data could lead to an interruption and replanning of the irradiation series when necessary. The ultimate goal is a system that can correct the path of the ion beam in real-time.

The Timepix3 chip developed at CERN is used in the new ADVACAM imaging device. (Image: CERN)

This device exemplifies successful knowledge transfer, showcasing how technology initially developed for detectors used in fundamental physics research can be applied in healthcare.

“When we started developing pixel detectors for the LHC we had one target in mind – to detect and image each particle interaction and thereby help physicists to unravel the secrets of Nature at high energies. The Timepix detectors were developed by the multidisciplinary Medipix Collaborations whose aims are to take the same technology to new fields. Many of those fields were completely unforeseen at the beginning and this application is a brilliant example of that,” says Michael Campbell, Spokesperson of the Medipix Collaborations.

ndinmore Wed, 03/06/2024 - 09:01 Publication Date Wed, 03/06/2024 - 10:03

The Open Quantum Institute launches its pilot phase at CERN

Mon, 04/03/2024 - 16:46
The Open Quantum Institute launches its pilot phase at CERN

The Open Quantum Institute (OQI) passes a new milestone today, with the operational launch at CERN. Following a successful one-year incubation period led by the Geneva Science and Diplomacy Anticipator (GESDA), the new, three-year CERN-based pilot will build on the efforts to date to help unleash the full power of quantum computing for the benefit of all.

Proposed, designed, and incubated through GESDA, in collaboration with some 180 experts from all over the world, the OQI is a multilateral science diplomacy initiative, uniting academia, technology companies, the private sector, the diplomatic community, philanthropy organisations and global citizens in a joint effort towards more open and inclusive quantum computing. By facilitating equal access to cutting-edge nascent technologies, the OQI seeks to accelerate the potential of quantum computing for all society and to support the development of concrete quantum solutions aimed at achieving the United Nations’ Sustainable Development Goals (SDGs).

During its pilot phase, hosted at CERN and supported by the Union de Banques Suisses (UBS), the OQI will be part of CERN’s wider Quantum Technology Initiative (QTI), launched in 2020 and managed by the IT department. Building on QTI’s mission to explore the full potential of quantum technologies and to maximise their societal impact, the OQI will work to push the boundaries of geography and disciplines to ensure that quantum computing is harnessed to tackle some of the key global challenges.

“CERN offers ideal conditions for the development of the OQI, and my hope is that this initiative will not only be a success, but also a model of what scientific diplomacy can do to promote concrete projects of benefit to humanity”, says Fabiola Gianotti, CERN Director-General. “During the pilot phase, the OQI will benefit from CERN's experience in deploying scientific and technological progress to the benefit of society. We look forward to working with GESDA and other partners from academia, industry and government to ensure that quantum computing is accessible to all, including underserved regions of the world."

The focus will lie on the selection of SDG-related use cases to explore applications of quantum computing in fields like health, energy, climate action, clean water, and food security. Some examples of potential projects include: improving the sustainability of global food systems through quantum computing optimisation (addressing SDG 2, zero hunger); finding quantum machine learning solutions to improve medical imaging accuracy and early diagnosis of diseases (addressing SDG 3, good health and well-being); and using quantum computing simulation to reduce carbon dioxide in the atmosphere (addressing SDG 13, climate action).

“The UN’s SDGs represent the international community’s collective view of what the greatest societal challenges are today,” says Enrica Porcari, Head of CERN’s IT department. “This is why we are proud to host the OQI at CERN and to provide a platform for innovation, fostering real-world applications of quantum computing to address the SDGs.”

CERN will host the OQI from 2024 to 2026 and support three or four projects targeting SDG-related use cases. It will also lay the foundation for the next phase of the programme and potentially become a reference point for other initiatives aimed at deploying quantum technologies to address societal challenges. GESDA will remain the science diplomacy advisor and fundraiser, helping to ensure the continuity of the initiative and contributing to its diplomatic engagement, while UBS will act as the lead support partner, ensuring further growth of the institute.

Organisations and individuals, committed to human-centred, inclusive and responsible quantum computing, can play their part in OQI by submitting use cases for SDGs, developing educational tools, curating the diplomatic dialogue on quantum computing and much more.

For full details on how to get involved, please visit the website, and follow OQI on LinkedIn and X.

abelchio Mon, 03/04/2024 - 15:46 Byline Anastasiia Lazuka Publication Date Tue, 03/05/2024 - 17:31

LHCb observes a new decay mode of the charmed beauty meson

Mon, 04/03/2024 - 11:15
LHCb observes a new decay mode of the charmed beauty meson The LHCb detector (Image: M. Brice/CERN)

The LHCb collaboration recently reported the first observation of the decay of the Bc+ meson (composed of two heavy quarks, b and c) into a J/ψ charm-anticharm quark bound state and a pair of pions, π+π0. The decay process shows a contribution from an intermediate particle, a ρ+ meson that forms for a brief moment and then decays into the π+π0 pair.

The Bc+ is the heaviest meson that can only decay through the weak interactions, via the decay of one heavy constituent quark. Bc+ decays into an odd number of light hadrons and a J/ψ (or other charm-anticharm quark bound states, called “charmonia”) have been studied intensively and have been found to be in remarkable agreement with the theoretical expectations. The decay of Bc+ into a J/ψ and a π+π0 pair is the simplest decay into charmonium and an even number of light hadrons. It has never been observed before, mainly because the precise reconstruction of the low-energy π0 meson through its decay into a pair of photons is very challenging in an LHC proton-proton collision environment.

A precise measurement of the Bc+→J/ψπ+π0 decay will allow better understanding of its possible contribution as a background source for the study of other decays of Bc mesons as well as rare decays of B0 mesons. From the theoretical point of view, decays of Bc into J/ψ and an even number of pions are closely related to the decays of the τ lepton into an even number of pions, and to the e+e– annihilation into an even number of pions. Precise measurements of e+e– annihilation into two pions in the ρ mass region (as in the Bc decay discussed here) are crucial for the interpretation of results from the Fermilab g-2 experiment measuring the anomalous magnetic dipole moment of the muon, since low-energy e+e– annihilation into hadrons is an important source of the uncertainty of the g-2 measurements.

The ratio of the probability of the new decay to that of the decay of Bc+ into J/ψπ+ has been calculated by various theorists over the last 30 years. Now these predictions can finally be compared with an experimental measurement: most predictions agree with the new result obtained by LHCb (2.80±0.15±0.11±0.16).

The large number of b-quarks produced in LHC collisions and the excellent detector allows LHCb to study the production, decays and other properties of the Bc+ meson in detail. Since the meson’s discovery by the CDF experiment at the Tevatron collider, 18 new Bc+ decays have been observed (with more than five standard deviations), all of them by LHCb.

Read more in the LHCb paper.

ptraczyk Mon, 03/04/2024 - 10:15 Byline LHCb collaboration Publication Date Mon, 03/04/2024 - 10:06

Accelerator Report: Advancing smoothly through recommissioning and overcoming challenges

Thu, 29/02/2024 - 11:40
Accelerator Report: Advancing smoothly through recommissioning and overcoming challenges

On 16 February, the symbolic LHC key was officially handed over to the Operations team, marking the start of the hardware recommissioning phase for the LHC. Early this week, 8600 hardware tests were successfully executed, out of the 10 336 tests that have to be performed. The injection of the first protons into the LHC is scheduled for 11 March, but could be brought forward by a few days if all goes well.

Meanwhile, the commissioning of the LHC injector chain is advancing smoothly. Linac4 is consistently delivering beams to the PS Booster, which has now set up and tuned all operational beams for downstream users. The PS has also set up the initial beams required by the SPS, including a single-bunch LHC beam and a low-intensity version of the beam that is destined for the SPS North Area experiments.

On the SPS front, hardware commissioning is proceeding according to plan, though not without some challenges. The “heat run”, a critical step in the commissioning process, involves pulsing the main magnets intensively for about 12 hours, with a current close to the maximum average current the magnets can operate with. The aim of the heat run is to detect any anomalies in the cooling of the magnets. Under normal conditions, the magnets will reach their steady state temperature after 20 to 30 minutes.

Last week, only 10 minutes after the beginning of the heat run, the operators in the CERN Control Centre (CCC) received an alarm: one or more magnets in one of the SPS sextants (one sixth of the machine’s circumference) had overheated. The magnets are protected against overheating; this protection cuts the electrical current circulating through the magnets to avoid any damage. A prompt intervention by experts equipped with thermal cameras identified the problematic magnet, and an investigation revealed that rubber debris from an anti-return valve was obstructing the cooling water flow. The issue was addressed by cleaning all 110 filters in the affected sextant and flushing the circuit, ensuring that no rubber debris was left. A second heat run confirmed that all the magnets are now operating at normal temperatures.

Overall, both hardware and beam commissioning activities across the accelerator complex are progressing well. Despite some issues, typical of the annual recommissioning, nothing has jeopardised the beam delivery schedule so far.

This thermal image clearly shows a significant temperature difference between the magnet on the left (in blue) and the overheating magnet on the right (in yellow). (Image: CERN) The water filter blocked with rubber debris. (Image: CERN)


anschaef Thu, 02/29/2024 - 10:40 Byline Rende Steerenberg Publication Date Thu, 02/29/2024 - 10:38

We love your CERN poems

Wed, 28/02/2024 - 12:15
We love your CERN poems

CERN community, we asked you to send us your CERN-related Valentine’s poems, thank you for all the entries that we received! It wasn’t easy to pick a favourite, but in the end, here is our winning English poem:

Ninety five percent of the Universe
has not been discovered, yet
My search for perfection stopped
when I saw you – si parfaite

You Opened the Gateway to my heart
You’re in all my Ideas, fair and Square
The force that draws me to you
Is stronger than the ions from LEIR

I had my whole week blocked
To just look at you in awe
until you broke my heart by saying
“I work in Prevessin”

When it comes to you,
I don’t have to think twice
Will you meet me halfway
At CERN Animal Shelter for Computer Mice?

In the end it’s you and me, 
Surrounded by all this neige
Our own little Quantum Entanglement
Where Data becomes Knowledge

By Varsha Bhat (IT/CD)

A special mention also goes to the CMS and ATLAS haikus:

What is CMS?
Compact Muon Solenoid.
The best detector.

By Sofia Hurst (EP/CMX)

I love you, ATLAS.
CMS got long bus rides.
We got point 1. ha.

By Rea Thornberry (EP/UAT)

The authors of the winning English poem and winning French poem each receive a goodie bag from the CERN shop including “I love CERN” socks, an attractive magnetic pencil and a Standard Model notebook to compose more odes to technology.

Thank you once again to everyone who entered. The full list of poems is available here: (CERN login required).


katebrad Wed, 02/28/2024 - 11:15 Byline Internal Communication Publication Date Thu, 02/29/2024 - 12:13

ABB and CERN identify 17.4% energy-saving opportunity in the Laboratory’s cooling and ventilation motors

Wed, 28/02/2024 - 11:34
ABB and CERN identify 17.4% energy-saving opportunity in the Laboratory’s cooling and ventilation motors

In a joint research project conducted between 2022 and 2023, ABB and CERN developed a roadmap for reducing the energy consumption of CERN’s cooling and ventilation systems via data-driven energy efficiency audits. These systems are responsible for the cooling and ventilation of CERN’s accelerator complex, experimental areas and data centres. The roadmap identified potential annual energy savings of up to 31 gigawatt-hours (GWh). If achieved, these savings could be enough to power more than 18,000 European households(1) and could avoid 4 kilotonnes of CO2 emissions(2), the same as planting 420,000 trees(3).

Energy efficiency audits involve evaluating the performance and efficiency of motors, based on their operating data. Such audits help large facilities like CERN to identify the most significant energy-saving opportunities across whole groups of motors. CERN and ABB experts assessed a wide variety of data from motors used for various cooling and ventilation applications. They combined data from multiple sources, including digitally connected motors, CERN’s supervisory control and data acquisition (SCADA) system, which is responsible for the control and monitoring of the cooling and ventilation installations, and data gathered directly from pumps, piping and instrumentation. The experts analysed the efficiency of the whole system in order to pinpoint the motors that present the best business case for energy efficiency upgrades.

Giovanni Anelli, Head of CERN’s Knowledge Transfer group, said, “The collaboration with ABB was set up with the aim of optimising the Laboratory’s cooling and ventilation infrastructure to reduce its energy consumption, and is in line with CERN’s commitment to minimise its environmental footprint as well as to share the findings publicly for the benefit of society. It’s an excellent example of collaboration where each side brings its own contribution to the table. CERN brings its large-scale infrastructure and ABB contributes with its technology and service expertise. We are very happy with the final result of this research project as we have exceeded our goal of identifying a 10-15% energy efficiency improvement.”

“We are proud to cooperate with CERN and to support its goal to conduct physics research with a low-carbon footprint by helping it to improve the energy efficiency of its cooling and ventilation systems,” said Erich Labuda, President of the Motion Services division at ABB.

CERN’s next step will be to selectively upgrade motors with the highest energy-saving potential, based on the data collected during the audit.

(1) EU average (~1670 kWh/year)

(2) Electricity Maps | Live 24/7 CO2 emissions of electricity consumption

(3) How Much CO2 Does A Tree Absorb? – One Tree Planted


Read the press release published by ABB today.

anschaef Wed, 02/28/2024 - 10:34 Byline CERN Knowledge Transfer group Publication Date Wed, 02/28/2024 - 10:29

Computer Security: The hardship of three security paradigms

Mon, 26/02/2024 - 14:22
Computer Security: The hardship of three security paradigms

Bravo to all those who participated in the Bull**** Bingo in the last Bulletin issue, in particular to those who sent in their solution and won a delicious Hawaiian pizza topped with pineapple and a Coke. Given the many replies, it seems that our Bingo was too easy? But that’s what “security” should be: easy, straightforward, simple. Paradigm #1 ─ the “KISS” paradigm: “Keep it simple, stupid”.

Unfortunately, this simplicity is spoiled time and again by the complex computing environment at CERN mixing the divergent needs of academia (research and computing sector), administration (finance and HR sector) and industry (the accelerator sector); by CERN’s legacy of using its resources for personal business like sending/receiving private emails, hosting personal webpages, or our bring-your-own-device (BYOD) policy to connect all of your own devices to CERN’s campus network; by the cacophony of historically grown systems performing similar ─ but not identical ─ tasks (CDS/CERNBox/EDMS/EOS/Google Workspaces/MyFiles/OneDrive/Sharepoint, or Kubernetes vs OpenStack vs OpenShift); and the problems coming with the cacophony of terminating old and outdated services (like the very slow and complicated AFS and DFS migration to CERNBox, killing the old SSO for the benefit of  the new one, or moving Drupal-hosted websites to WordPress). So, KISS is hardly a reality at CERN. We should strive to do better. Simpler. More homogenous. More centralised. More controlled. KISS.

Unfortunately, again, and given additional constraints ─ lack of resources or time pressure ─ paradigm #2 kicks in: “cheap, convenient, secure ─ pick two”. That makes security a permanent uphill struggle as nobody would pick “secure” given that “cheap” and “convenient” always trump. Would you? Instead, security is given low priority, filed to the back, and applied only when time and resources allow (or the implementers are security aware). Again, we should strive to do better. Last year’s audit on cybersecurity urged higher priority and recommended that the Organization “define and implement a process to ensure security is considered in any project” and “implement a security risk management process” under the auspices of the Computer Security team (a dedicated Bulletin article on this topic will be published soon).

Following general best practices ─ and as re-emphasised by the aforementioned audit ─ the Computer Security team has always aimed to deploy and deepen “defence-in-depth” ─ paradigm #3. With your help ─ given that “security is everyone’s responsibility” (Bingo solution C1) ─ “2FA is a big step forward for account protection” (A2) and we are grateful to now have more than 10 000 accounts under this protection. On another defence level, we succeed well at dismissing malicious websites, domains and IPs on the firewall level, but struggle to filter malicious emails (and promise to improve on that during 2024). Still, we are counting on you to detect those that made it through: “Only the link behind a text/QR code reveals its truth” (B3). But we also try to help you, as “CERN’s anti-malware software is free for you to download” (E4)*. Defence-in-depth. Hard to implement, but possible to have.

Hence, these paradigms “KISS ─ keep it simple, stupid” and “defence-in-depth” go hand in hand once we all jointly pick the right two of “cheap, convenient, secure”. Let’s overcome the hardship imposed by these three paradigms. You and us together. Together securing the Organization. Preventing any disasters.


* The fifth solution is D5 ─ “Encryption is easy; key management is complicated” ─ but that is a technical detail being taken care of inside IT.


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

anschaef Mon, 02/26/2024 - 13:22 Byline Computer Security team Publication Date Mon, 02/26/2024 - 13:18

Indico: 20 years of event managing

Mon, 26/02/2024 - 12:36
Indico: 20 years of event managing

Thanks to 300 active servers located in 52 different countries, some 400 000 users can experience the powerful and user-friendly features that Indico offers to any event organiser. Born about twenty years ago with the “Event 0” – the CHEP 04 scientific conference – today Indico serves not only the large community of particle physicists working at CERN but also a plethora of other institutions, including the conferences and the UN.

Indico started as a follow-up to the AgendaMaker tool that a small team of developers had created for the ATLAS collaboration, which today is still one of the most active users of the platform. “Following that initial request, a funding request was made to the EU to evolve from a meeting-oriented application to a catch-all platform where we could host a one-hour meeting as well as a one-week conference with parallel sessions,” recalls Jean-Yves Le Meur, in charge of the early developments of Indico. “Since the beginning, Indico was designed to be modular, and I am amazed to see today how the successive managers of this system have extended and enriched its features in all directions.”

In 2023, the Indico application managed some 145 000 events worldwide and accommodated a regular flow of requests coming from the community, whose members also contribute to the development of the open source software package. Last December, a big release – Indico 3.3 – was made available on the CERN-managed instances, and the release for the general public will follow in the coming months. “The release has brought a lot of improvements compared to previous versions,” explains Adrian Mönnich, Indico's project manager and lead developer. “For example, thanks to contributions from the UN, we have improved the accessibility of Indico. Indeed, the application is now more suitable for visually impaired people who use screen readers. The existing Indico check-in mobile application has also been completely rewritten, and Indico now supports the generation of fully customisable PDF documents, including receipts, certificates of attendance and any other document that the user might need. Once generated, the documents can be downloaded from the registration page.”

The continuous Indico upgrade never stops, and here is a sneak peek of what we can expect in 2024: “We plan to release a brand-new conference timetable interface, which will replace the current one that dates back to 2008,” says Pedro Ferreira, leader of the Conferencing Technologies section. “The team is also working on a new integration with the next-generation conferencing rooms, and we hope to make significant steps towards a refreshed Indico user interface including greater mobile friendliness.”

Indico is a CERN-developed open source software. Since last year, a new governance model has been in place to encourage contributions from partner institutions. Find more technical information here.   

Events and you

Find relevant Indico events and what’s on at CERN and beyond:

anschaef Mon, 02/26/2024 - 11:36 Byline Antonella Del Rosso Publication Date Wed, 02/28/2024 - 10:34

ATLAS congratulates its 2023 Thesis Awards winners

Mon, 26/02/2024 - 12:24
ATLAS congratulates its 2023 Thesis Awards winners

The ATLAS collaboration celebrated the achievements of its exceptional PhD students at the recent Thesis Awards ceremony. Established in 2010, the ATLAS Thesis Awards recognise the remarkable contributions made by students to the ATLAS collaboration through their doctoral theses. Students play pivotal roles in the collaboration while gaining invaluable skills crucial to their professional pursuits.

The 2023 ATLAS Thesis Awards were announced on 15 February 2024 at a ceremony held at CERN's main auditorium. The award winners are: Joshua Beirer from CERN & Georg-August-Universität Göttingen (Germany), Prajita Bhattarai from Brandeis University (USA), Savannah Clawson from the University of Manchester (UK), Hassnae El Jarrari from Université Mohammed-V De Rabat (Morocco), Nicole Hartman from Stanford University & SLAC (USA), Samuel Van Stroud from University College London (UK), and Xiao Yang from the University of Science and Technology of China (China).

“PhD students aren’t just the beating heart of the ATLAS collaboration – they’re the brains behind many of our achievements,” said Antonella De Santo, Chair of the Thesis Awards Committee. “PhD students make up a significant fraction of ATLAS collaboration members and contribute to a diverse range of research areas, including physics analysis, detector operations and upgrades, and software and hardware developments. The ATLAS Thesis Awards are our way of recognizing and highlighting their outstanding achievements.”


Read the full story and explore the winning theses on the ATLAS website.

anschaef Mon, 02/26/2024 - 11:24 Byline Katarina Anthony Publication Date Mon, 02/26/2024 - 11:20

A new data centre at CERN

Fri, 23/02/2024 - 16:12
A new data centre at CERN The inauguration of the new data centre in Prévessin. From left to right: Pippa Wells, CERN’s Deputy Director for Research and Computing; Charlotte Warakaulle, CERN’s Director for International Relations; Aurélie Charillon, Mayor of Prévessins-Moëns; Joachim Mnich, CERN’s Director for Research and Computing; Yves Nussbaum, Director Marché Industrie, AXIMA; and Enrica Porcari, Head of Information Technology Department at CERN. (Image: CERN)

On 23 February 2024, a brand-new data centre was inaugurated on CERN’s Prévessin site (France), marking the completion of a major project for the Organization’s computing strategy. Spanning more than 6000 square metres and including six rooms for IT equipment with a cooling capacity of 2 MW each, the centre will host CPU (central processing unit) servers for physics data processing as well as a small amount of CPU servers and storage capacity for business continuity and disaster recovery (for example, when data is corrupted). CERN’s main data centre on the Meyrin site (Switzerland) will continue to house the majority of the Organization’s data storage capacity.

The rate of data production of the experiments at the Large Hadron Collider (LHC) continues to grow, already reaching some 45 petabytes per week, and this is expected to double in the era of the High-Luminosity LHC, the major upgrade of CERN’s current flagship accelerator, the LHC. The data from these experiments is fed into the Worldwide LHC Computing Grid (WLCG), a collaboration of around 170 data centres distributed across more than 40 countries, with a storage capacity of about 3 exabytes and one million CPU cores distributed across the network. While the Meyrin data centre has so far performed the Tier 0 role, that is, the core for the LHC Computing Grid, the Prévessin centre will provide vital additional computing capacity to CERN.

The new building was built in a record time of less than two years. It complies with strict technical requirements to ensure its environmental sustainability, and is equipped with an efficient heat-recovery system that will contribute to heating buildings on the Prévessin site.

The backbones of our interconnected world, data centres are energy-intensive infrastructures. According to a recent report, their energy consumption accounts for about 1.5% of the European Union’s total electricity consumption. Two parameters characterise the environmental sustainability of a data centre: the power usage effectiveness (PUE) – the ratio of total data centre input power to IT load power – and the water usage effectiveness (WUE) – the ratio between the use of water in data centre systems and the energy consumption of the IT equipment.

The new Prévessin centre has a PUE target of 1.1, lower than the worldwide average of 1.6, and close to 1.0, which would be the value for a perfectly efficient data centre, where all the power is delivered to the IT equipment.

It has a WUE target of 0.379 litres per kWh thanks to an innovative water recycling system. The cooling system will be automatically triggered when the outside temperature reaches 20 degrees Celsius. Five huge fan-walls installed in each room will ensure that the overall temperature does not exceed 32 degrees Celsius.

The new centre was designed, built and will be operated in the framework of a FIDIC (International Federation of Consulting Engineers) Gold Book contract, which also ensures its financial sustainability. The building’s IT rooms will gradually be equipped with up to 78 racks each. Starting from the top-floor rooms, they are expected to be fully equipped over the next ten years.

ndinmore Fri, 02/23/2024 - 15:12 Byline Antonella Del Rosso Publication Date Fri, 02/23/2024 - 15:10

From particle physics to medicine

Thu, 22/02/2024 - 17:55
From particle physics to medicine


Did you know that particle accelerators are also used to treat cancer? That medical imaging has taken great leaps forwards thanks to the crystals and chips developed for particle physics? And that CERN is home to a facility that develops isotopes for medical research?

Ever since X-rays were discovered by Wilhelm Röntgen in 1895, physics and medicine have been closely intertwined. Medical imaging and cancer treatments have benefited from developments in particle physics over the years, and the innovations continue today, including in collaboration with CERN.

As part of CERN’s 70th anniversary celebrations, doctors, biologists and physicists will walk you through how the collaboration between fundamental physics and medicine is leading to innovative treatment methods and diagnostic techniques. One special patient – a researcher, writer and populariser of science – will share with us his experience of being treated for cancer in one of the four European centres for hadron therapy.

Entrance to the event is free, but registration is mandator. Click here to register.

This is the second in a series of events being organised to mark CERN’s 70th anniversary.

From the big questions in physics today to the machines of the future and the human adventure of scientific collaboration without borders, CERN invites you to discover the many facets and benefits of its research through lectures, debates and artistic performances.

Have your diaries at the ready. Consult the full programme of events on the CERN at 70 webpage.


cmenard Thu, 02/22/2024 - 16:55 Publication Date Thu, 02/22/2024 - 16:45

CERN’s accelerators gear up for action after the winter maintenance break

Wed, 21/02/2024 - 12:32
CERN’s accelerators gear up for action after the winter maintenance break

As winter bids farewell, the recommissioning of CERN’s accelerator complex gathers pace, with the scientific community eagerly awaiting particle beams in their experiments. Following the traditional winter break (called the “year-end technical stop” (YETS)), the Linear accelerator 4 (Linac4) is the first machine to resume beam operation, followed by the downstream machines: the Proton Synchrotron Booster (PSB), Proton Synchrotron (PS), Super Proton Synchrotron (SPS) and Large Hadron Collider (LHC).

Beam entered Linac4 on 5 February, and the PS Booster a few days later. This week, the first beam was injected into the PS, which is now preparing the first beam for the SPS beam commissioning, scheduled to start on 1 March. The first particle beams will reach the LHC on 11 March.

The expectations for 2024 are high. In the LHC, the focus is on luminosity production with proton–proton collisions. The luminosity is an important indicator of the performance of an accelerator: it is proportional to the number of collisions that occur in the experiments in a given amount of time. The higher the luminosity, the more data the experiments can gather to allow them to observe rare processes.

The 2024 LHC run will conclude with lead–lead ion collisions; the first lead ions will be injected into the LHC on 6 October. The 2024 run is scheduled to end on 28 October.

The resumption of operation of the accelerator complex heralds a new year of physics, surely leading to important physics results. As the countdown to 11 March continues, the operations and other expert teams are working diligently to prepare the machines and the beams for another successful physics run.

anschaef Wed, 02/21/2024 - 11:32 Byline Rende Steerenberg Publication Date Thu, 02/22/2024 - 09:31

CMS collaboration explores how AI can be used to search for partner particles to the Higgs boson

Tue, 20/02/2024 - 14:21
CMS collaboration explores how AI can be used to search for partner particles to the Higgs boson Event display showing two collimated bursts of light. (Image: CMS collaboration)

As part of their quest to understand the building blocks of matter, physicists search for evidence of new particles that could confirm the existence of physics beyond the Standard Model (SM). Many of these beyond-SM theories postulate the need for additional partner particles to the Higgs boson. These partners would behave similarly to the SM Higgs boson, for example in terms of their “spin”, but would have a different mass.

To search for Higgs partner particles, scientists at the CMS collaboration look for the signatures of these particles in the data collected by the detector. One such signature is when the particles decay from a heavy Higgs partner (X) particle to two lighter partner particles (φ), which in turn each decay into collimated pairs of photons. Photon signatures are ideal to search for particles with unknown masses as they provide a clean, well-understood signature. However, if the φ is very light, the two photons will significantly overlap with each other and the tools usually applied for the photon identification fall apart.

This is where artificial intelligence (AI) comes in. It is well known that machine learning computer vision techniques can differentiate between many faces, and now such AI methodologies are becoming useful tools in particle physics.

The CMS experiment searched for the X and φ partners of the Higgs boson using the hypothetical process X→φφ, with both φ decaying to collimated photon pairs. To do this, they trained two AI algorithms to distinguish the overlapping pairs of photons from noise, as well as to precisely determine the mass of the particle from which they originated. A wide range of masses was explored. No evidence for such new particles was seen, enabling them to set upper limits on the production rate of this process. The result is the most sensitive search yet performed for such Higgs-like particles in this final state.

How can the scientists test the AI’s effectiveness? It is not as easy as verifying AI facial differentiation, where you can simply check by looking. Thankfully, the SM has well-understood processes, which CMS physicists used to validate and control the AI techniques. For example, the η meson, which also decays to two photons, provided an ideal test bench. Scientists at CMS were able to cleanly identify and reconstruct the η meson when searching for its decay into photons when they applied these AI techniques.

This analysis clearly shows that AI algorithms can be used to cleanly identify two-photon signatures from the noise and to search for new massive particles. These machine learning techniques are continuously improving and will continue to be used in unique analyses of LHC data, extending CMS searches to even more challenging cases.

Read more here



ndinmore Tue, 02/20/2024 - 13:21 Byline CMS collaboration Publication Date Wed, 02/21/2024 - 09:30

AEgIS experiment paves the way for new set of antimatter studies by laser-cooling positronium

Fri, 16/02/2024 - 15:50
AEgIS experiment paves the way for new set of antimatter studies by laser-cooling positronium

AEgIS is one of several experiments at CERN’s Antimatter Factory producing and studying antihydrogen atoms with the goal of testing with high precision whether antimatter and matter fall to Earth in the same way. In a paper published today in Physical Review Letters, the AEgIS collaboration reports an experimental feat that will not only help it achieve this goal but also pave the way for a whole new set of antimatter studies, including the prospect to produce a gamma-ray laser that would allow researchers to look inside the atomic nucleus and have applications beyond physics.

To create antihydrogen (a positron orbiting an antiproton), AEgIS directs a beam of positronium (an electron orbiting a positron) into a cloud of antiprotons produced and slowed down in the Antimatter Factory. When an antiproton and a positronium meet in the antiproton cloud, the positronium gives up its positron to the antiproton, forming antihydrogen.

Producing antihydrogen in this way means that AEgIS can also study positronium, an antimatter system in its own right that is being investigated by experiments worldwide.

Positronium has a very short lifetime, annihilating into gamma rays in 142 billionths of a second. However, because it comprises just two point-like particles, the electron and its antimatter counterpart, “it’s a perfect system to do experiments with”, says AEgIS spokesperson Ruggero Caravita, “provided that, among other experimental challenges, a sample of positronium can be cooled enough to measure it with high precision”.

This is the feat accomplished by the AEgIS team. By applying the technique of laser cooling to a sample of positronium, the collaboration has already managed to more than halve the temperature of the sample, from 380 to 170 degrees kelvin. In follow-up experiments the team aims to break the barrier of 10 degrees kelvin.

AEgIS’ laser cooling of positronium opens up new possibilities for antimatter research. These include high-precision measurements of the properties and gravitational behaviour of this exotic but simple matter–antimatter system, which could reveal new physics. It also allows the production of a positronium Bose–Einstein condensate, in which all constituents occupy the same quantum state. Such a condensate has been proposed as a candidate to produce coherent gamma-ray light via the matter-antimatter annihilation of its constituents – laser-like light made up of monochromatic waves that have a constant phase difference between them.

“A Bose-Einstein condensate of antimatter would be an incredible tool for both fundamental and applied research, especially if it allowed the production of coherent gamma-ray light with which researchers could peer into the atomic nucleus.” says Caravita.

Laser cooling, which was applied to antimatter atoms for the first time about three years ago, works by slowing down atoms bit by bit with laser photons over the course of many cycles of photon absorption and emission. This is normally done using a narrowband laser, which emits light with a small frequency range. By contrast, the AEgIS team uses a broadband laser in their study.

“A broadband laser cools not just a small but a large fraction of the positronium sample,” explains Caravita. “What’s more, we carried out the experiment without applying any external electric or magnetic field, simplifying the experimental set-up and extending the positronium lifetime.”

The AEgIS collaboration shares its achievement of positronium laser cooling with an independent team, which used a different technique and posted their result on the arXiv preprint server on the same day as AEgIS.

Further material:
Video collection
Photo collection 1
Photo collection 2

About AEgIS:
The AEgIS collaboration is composed of several research groups from CERN, Istituto Nazionale di Fisica Nucleare (units of Milano, Pavia and the Trento Institute for Fundamental Physics and Applications), the University of Oslo, the Universite Paris-Saclay and the Centre National de la Recherche Scientifique, the University of Liverpool, the Warsaw University of Technology, the University of Trento, the Jagiellonian University of Krakow, the Raman Research Institute of Bangalore, the University of Innsbruck, the University and the Politecnico of Milan, the University of Brescia, the Nicolaus Copernicus University in Torun, the University of Latvia, the Institute of Physics of the Polish Academy of Sciences and the Czech Technical University of Prague.

sandrika Fri, 02/16/2024 - 14:50 Publication Date Thu, 02/22/2024 - 16:30

Accelerator Report: The accelerator complex gears up for action after the yearly winter maintenance break

Thu, 15/02/2024 - 11:11
Accelerator Report: The accelerator complex gears up for action after the yearly winter maintenance break

The symbolic key to resume LHC operations will be handed over from the ACE (Accelerator Coordination and Engineering) group in the Engineering department to the Operations group on Friday, 16 February, kicking off the 2024 “particle season”.

As winter bids farewell, the recommissioning of the accelerator complex gathers pace, with the scientific community eagerly awaiting particle beams in their experiments. Following the year-end technical stop (YETS), Linac4 is the first machine to resume beam operation, followed by the downstream machines: the PS Booster, PS, SPS and LHC.

Beam entered Linac4 on 5 February, two days ahead of schedule – extra time welcomed by the Linac team. During the YETS, work was done on the chain of accelerating cavities, requiring a re-phasing – a challenging and often time-consuming task. To do so, the acceleration of the particle beam is optimised as the beam goes down the Linac: the voltage waves in the cavities are timed correctly as the beam passes by, ensuring optimum acceleration in each of the cavities and bringing the energy to 160 MeV at the end of the Linac.

This week, the beam was then sent to the PS Booster. The operations team has one week to prepare for the first beam to be injected into the PS on 21 February. The PS will then have to prepare the first beam for the SPS beam commissioning, scheduled to start on 1 March. The first particle beams will reach the LHC on 11 March, initially with one to a few bunches at most.

Before injecting particle beams, the hardware recommissioning coordinators of each machine and the many equipment experts have the task of meticulously recommissioning and validating all the subsystems. They run the machine “as if” particle beams were being accelerated, but without particles. They go through checklists, validating and ticking off thousands of tests, to give the green light for beam commissioning.

The expectations for 2024 are high. Firstly, in the LHC, the focus is on luminosity production with proton–proton collisions, aiming at an unprecedented accumulation of luminosity of up to 90 fb-1. This, together with the accumulation of luminosity forecast for the 2025 run, should provide a sizeable analysis data set to keep physicists busy during Long Shutdown 3. The 2024 LHC run will conclude with lead–lead collisions; the first lead ions will be injected into the LHC on 6 October. The 2024 run is scheduled to end on 28 October.

The injector chain has an ambitious year ahead as well: the injectors have a busy fixed-target programme and will provide beams to all the experimental facilities. The first fixed-target physics will start in the PS East Area on 22 March, followed by the PS n_TOF facility on 25 March. Physics in ISOLDE, downstream of the PS Booster, will start on 8 April, followed by the SPS North Area on 10 April. The antimatter factory is set to start delivering antiprotons to its experiments on 22 April. The AWAKE facility, behind the SPS, will run for ten weeks in total (in blocks of two or three weeks) until the middle of September, when the dismantling of the no-longer-used CERN Neutrinos to Gran Sasso (CNGS) target facility will start, to allow for a future extension of the AWAKE facility. The SPS HiRadMat facility will see four 1-week runs.

Beyond this busy physics programme, many machine development studies and tests are planned in all the machines. One of these tests will take place between mid-March and early June to configure the Linac3 source to produce magnesium ions, which will be accelerated in Linac3, injected into LEIR, and possibly even into the PS. This test will help assess the feasibility and performance of magnesium beams in the accelerator complex, for potential future applications in the LHC and the SPS North Area.

The resumption of operation of the accelerator complex heralds a new year of physics, surely leading to important physics results. As the countdown to 11 March continues, the operations and expert teams are working diligently to prepare the machines and the beams for another successful physics run.

anschaef Thu, 02/15/2024 - 10:11 Byline Rende Steerenberg Publication Date Thu, 02/15/2024 - 10:08

Happy hundredth Herwig!

Wed, 14/02/2024 - 13:11
Happy hundredth Herwig! Learn from a lifetime of physics, come to the 1 March event.

Join in a rousing chorus of “Happy Birthday” on Friday 1 March, as CERN celebrates the 100th birthday of Herwig Schopper, CERN Director-General from 1981 to 1988.

Herwig has made landmark contributions to nuclear and particle physics and to related technologies. In his early career, he played a key role in shaping today’s physics research landscape in Germany, establishing laboratories and institutions before going on to leadership roles at DESY and CERN.

After retirement, not content to rest on his laurels, Herwig embarked on a new career: as a science diplomat. In this capacity, he played a leading role in the establishment of the SESAME laboratory in Jordan, a synchrotron light facility for the Middle East and neighbouring regions.

Over his remarkable career, Herwig has rubbed shoulders with the giants of the field, counting many as friends. Few have had the opportunity to witness the evolution of particle physics from such a privileged vantage point.

Now is your chance to hear this history first hand. On Friday 1 March from 2 p.m. in the Main Auditorium, current and former CERN directors, eminent scientists and Herwig himself will speak, before participants are invited to raise a glass at a drinks reception. Full details are available here.

Register now to join the celebration of Herwig’s life and achievements to date.

(Video: CERN)

katebrad Wed, 02/14/2024 - 12:11 Publication Date Thu, 02/15/2024 - 09:30

Computer Security: Bull**** Bingo

Tue, 13/02/2024 - 15:50
Computer Security: Bull**** Bingo

There are many mantras and claims floating around about cybersecurity. Some of them leave no room for doubt, like “defence in depth”, which suggests deploying protective means at every level of the hardware and software stack, or “KISS ─ keep it simple, stupid” to avoid over-complication and too many deviations from the “standard” cybersecurity system. Other, more unfortunate statements also hold true. For example, “convenient, cheap, secure ─ pick two” makes “secure” always the least attractive option, as it brings no immediate benefits. However, some other mantras and claims are simply not true. Plain wrong. Or, excuse my language, “bull****”.

Indeed, computer security is never straightforward. Often, there is no single solution, but a series of complementary solutions is needed, like how our xorlab ActiveGuard solution works together with the Microsoft SPAM filter. Often a holistic solution cannot be found, for example when the quick fix of having two-factor authentication (2FA) for the new CERN SSO was deployed, which meant that the old SSO was left to die, and the non-holistic solutions we are looking at for how to deploy 2FA to LXPLUS and Windows Terminal Servers in the future. Generally, computer security requires the aforementioned “defence in depth”: individually, multiple protective layers, each with a defined (implementation) scope, a limited coverage and holes are insufficient. But together, they provide adequate overall protection to the Organization that is pragmatic, balanced and efficient. Combined, they keep the cybersecurity risks and threats to the Organization under control.

So, while we acknowledge that there is no single solution to “cybersecurity”, there are many wrong solutions. Wrong statements. Wrong mantras. Bull****. In order to give you an idea of what we mean, let’s play “Bull**** Bingo”. Below are 25 statements we have heard in the past about cybersecurity, best security practices and cybersecurity implementation, some even from esteemed colleagues. Can you spot where they went wrong?  








There is no malware for Apple devices

Software from the Google Play Store is harmless

Security is everyone’s responsibility

SSH on port 2222/tcp is more secure

SPAM and malware filtering is 100% effective


2FA is a big step forward for account protection

Emails from “” are legitimate

I'm personally not a target as I'm not interesting to attackers

Back-ups cannot be altered

I have nothing to hide


I would never fall for phishing

Only the link behind a text/QR code reveals its truth

CERN’s technical network is secure

A password written on a post-it is a good idea

QR codes always link to legit sites


A (free) VPN service protects me

Password protection on my laptop protects its data

My browser’s password manager is secure

CERN is not interesting to attackers

CERN’s anti-malware software is free for you to download


Using “https” means the website is secure

CERN’s outer perimeter firewall keeps all threats away

Cloud services cannot be hacked

Encryption is easy; key management is complicated

WiFi is always secure


The first three people to send  the five true statements to will win a bottle of Coca-Cola, as well as a “Hawaiian” pizza from CERN’s Restaurant 2.

Want to learn more about computer security incidents and issues at CERN? Read our monthly reports ( For more information, questions or advice, check out our website ( or contact us at

ndinmore Tue, 02/13/2024 - 14:50 Byline Computer Security team Publication Date Tue, 02/13/2024 - 14:46

Science Gateway welcomes its 100 000th visitor

Tue, 13/02/2024 - 15:39
Science Gateway welcomes its 100 000th visitor

On Tuesday, 6 February, CERN Science Gateway welcomed its 100 000th visitor.

Bavo Lens and Nicky Morren came from Hasselt to Geneva on a city break and said “visiting CERN is a must”.

“For me, as an engineer, it was great to be able to see high-tech machines like the Synchrocyclotron and ATLAS,” Lens said. “Congratulations to the guide who was able to explain the very complex material in understandable language. The reception building is very beautiful and offers wonderful exhibitions that explain how particle research works very clearly, even for those who are not gifted in science. We ended our visit in the restaurant, where we enjoyed the vegetarian options!”

Since the opening of CERN Science Gateway on October 8 2023, an average of 1000 visitors per day have enjoyed this new facility. The centre offers activities for all ages, including inviting young visitors from five years old to play and “see the invisible” while building up an interest in and connection to science and technology.

Having reached this milestone, the Visits service would like to send a big “thank you” to all its active guides. None of this would have been possible without the enormous dedication of each and every one of them, volunteering day after day to ensure that our visitors have an inspiring experience. 

For those who have not yet found the time to become a guide: take the first step and become part of this new era of outreach and education at CERN. The first step is usually the biggest, but the team will be there to support you at every stage of the journey.

ndinmore Tue, 02/13/2024 - 14:39 Publication Date Tue, 02/13/2024 - 14:37

CERN Council reviews progress of feasibility study for a next-generation collider

Tue, 13/02/2024 - 11:48
CERN Council reviews progress of feasibility study for a next-generation collider

After three years of work, mobilising the expertise of scientists and engineers around the world, the Feasibility Study for the Future Circular Collider (FCC) - a particle collider with a circumference of 90.7 km that could potentially succeed the High-Luminosity LHC in the mid-2040s – has now reached the half-way mark. The Feasibility Study is expected to be completed in 2025.

The CERN Council reviewed the work undertaken in a fruitful meeting on 2 February 2024. It congratulated and thanked all the teams involved in the study for the excellent and significant work done so far and for the impressive progress, and looks forward to receiving the final report in 2025.

Particle colliders have played a crucial role in elucidating the fundamental laws of nature and constituents of matter. The Feasibility Study for the FCC was launched in response to a recommendation from the 2020 update of the European Strategy for Particle Physics, whereby Europe, in collaboration with the worldwide community, should undertake a technical and financial feasibility study for a next-generation hadron collider at the highest achievable energy, with an electron-positron collider as a possible first stage.

If approved by CERN’s Member States in the coming years, the construction of the first stage, an electron-positron collider (FCC-ee), could start in the early 2030s and operate in the mid-2040s. The facility would operate for some 15 years, during which time the high-field magnet technology needed for the second stage, a proton-proton collider operating at an unprecedented collision energy of around 100 TeV (FCC-hh), could be developed and industrialised.

Accelerator, detector, and physics studies continue within the global FCC collaboration, spanning 150 institutes in 30 countries.

Relevant links:

abelchio Tue, 02/13/2024 - 10:48 Publication Date Tue, 02/13/2024 - 10:39

Quadrupoles are red, dipoles are blue…

Mon, 12/02/2024 - 17:22
Quadrupoles are red, dipoles are blue…

CERN community: this Valentine’s Day we’re asking you to compose an ode to technology.

Send us your CERN-related Valentine’s poem, written in English or French, and we’ll publish our favourites in the next Bulletin. We’ll also give a prize to the poem that we like the best. Poems must be a maximum of 20 lines, and the more CERN-specific the better. 

Here are our attempts to get you started:

Quadrupoles are red
Dipoles are blue
CERN’s magnets are cool
They’re attractive too

Protons are red,
Electrons are blue,
There’s neutrons as well
But you are my glu(on)
There once was an experimentalist,
Who was a great friend of a theorist.
She said to him:
“I give thee this ring”
And LHC made them their happiest.

Send your poem to by midnight CET on Sunday, 25 February. Please note that you must have a CERN email address to enter.

By taking part in this competition, you accept that your poem may be published in the next CERN Bulletin. If you wish, you can request that we publish it anonymously.

(Video: CERN)

katebrad Mon, 02/12/2024 - 16:22 Byline Internal Communication Publication Date Wed, 02/14/2024 - 09:09