Subscribe to RSS - News feed
Updated: 1 hour 10 min ago

Xcitement down under: Australia gets first X-band facility

Fri, 15/01/2021 - 11:22
Xcitement down under: Australia gets first X-band facility Achintya Rao achintya Fri, 01/15/2021 - 10:22 Some members of the X-Lab team along with the transport crew (Image: CERN)

On 16 September 2020, a container filled with pallets, boxes and electronic racks left CERN’s Meyrin site to embark on a two-month sea journey to the other side of the world. On 17 November, at precisely 3.12 p.m. local time, its ship docked at Port Melbourne, from where, following customs clearance earlier this year, the container and its contents were transported to a new home: the University of Melbourne.

The container held the components of the southern hemisphere’s first X-band radio-frequency test facility; “X-band” refers to the ultra-high-frequency at which the device operates. The device, half of the CERN facility known as XBOX-3, will soon be a part of the “X-Lab” at the University of Melbourne. Its journey resulted from an agreement signed between CERN and the Australian Collaboration for Accelerator Science in 2010.

XBOX-3 and its two predecessors were built at CERN in the context of the Compact Linear Collider (CLIC) study that envisions building a linear electron–positron collider with a collision energy of 380 GeV. They were built to develop the technology to accelerate particles to a high velocity over a relatively small distance. Such accelerators are described as possessing a high acceleration gradient. In addition to aiding the development of the next generation of particle accelerators, the technology of high-gradient acceleration is also useful for medical applications, such as radiotherapy, and in synchrotron light sources.

In 2015, CERN decided that half of XBOX-3 would eventually be sent to Australia to help its nascent accelerator community. “Having the only X-band facility this side of the equator is a huge boost to the growing accelerator-physics community in Australia. It will allow us to train specialists, do novel research and create exciting industry-engagement opportunities based on the many applications of accelerators,” says Suzie Sheehy, group leader of the Accelerator Physics Group at the University of Melbourne. “The Melbourne X-Lab team, which includes senior researchers, PhD students and support staff, is grateful for CERN’s contribution to our project.”

The device will be renamed MelBOX, in light of its new home, and will come online in its new avatar this year.

See more photos on CDS:

A new way to look for gravitational waves

Wed, 13/01/2021 - 09:57
A new way to look for gravitational waves Ana Lopes katebrad Wed, 01/13/2021 - 08:57 The EDGES radio telescope. (Image: Suzyj, CC BY-SA 4.0, via Wikimedia Commons)

In a paper published today in Physical Review Letters, Valerie Domcke of CERN and Camilo Garcia-Cely of DESY report on a new technique to search for gravitational waves – the ripples in the fabric of spacetime that were first detected by the LIGO and Virgo collaborations in 2015 and earned Rainer Weiss, Barry Barish and Kip Thorne the Nobel Prize in Physics in 2017.

Domcke and Garcia-Cely’s technique is based on the conversion of gravitational waves of high frequency (ranging from megahertz to gigahertz) into radio waves. This conversion takes place in the presence of magnetic fields and distorts the relic radiation from the early universe known as cosmic microwave background, which permeates the universe.

The research duo shows that this distortion, deduced from cosmic microwave background data obtained with radio telescopes, can be used to search for high-frequency gravitational waves generated by cosmic sources such as sources from the dark ages or even further back in our cosmic history. The dark ages are the period between the time when hydrogen atoms formed and the moment when the first stars lit up the cosmos.

“The odds that these high-frequency gravitational waves convert into radio waves are tiny, but we counterbalance these odds by using an enormous detector, the cosmos,” explains Domcke. “The cosmic microwave background provides an upper bound on the amplitude of the high-frequency gravitational waves that convert into radio waves. These high-frequency waves are beyond the reach of the laser interferometers LIGO, Virgo and KAGRA.”

Domcke and Garcia-Cely derived two such upper bounds, using cosmic microwave background measurements from two radio telescopes: the balloon-borne ARCADE 2 instrument and the EDGES telescope located at the Murchison Radio-Astronomy Observatory in Western Australia. The researchers found that, for the weakest possible cosmic magnetic fields, determined from current astronomical data, the EDGES measurements result in a maximum amplitude of one part in 1012 for a gravitational wave with a frequency of around 78 MHz, whereas the ARCADE 2 measurements yield a maximum amplitude of one part in 1014 at a frequency of 3−30 GHz. For the strongest possible cosmic magnetic fields, these bounds are tighter – one part in 1021 (EDGES) and one part in 1024 (ARCADE 2) – and are about seven orders of magnitude more stringent than current bounds derived from existing laboratory-based experiments.

Domcke and Garcia-Cely say that data from next-generation radio telescopes such as the Square Kilometre Array, as well as improved data analysis, should tighten these bounds further and could perhaps even detect gravitational waves from the dark ages and earlier cosmic times.

CMS collaboration releases its first open data from heavy-ion collisions

Tue, 12/01/2021 - 16:04
CMS collaboration releases its first open data from heavy-ion collisions Achintya Rao achintya Tue, 01/12/2021 - 15:04 A collision event recorded by CMS during the heavy-ion run of 2011 (Image: CERN)

For a few weeks each year of operation, instead of colliding protons, the Large Hadron Collider (LHC) collides nuclei of heavy elements (“heavy ions”). These heavy-ion collisions allow researchers to recreate in the laboratory conditions that existed in the very early universe, such as the soup-like state of free quarks and gluons known as the quark–gluon plasma. Now, for the first time, the Compact Muon Solenoid (CMS) collaboration at CERN is making its heavy-ion data publicly available via the CERN Open Data portal.

Over 200 terabytes (TB) of data were released in December, from collisions that occurred in 2010 and 2011, when the LHC collided bunches of lead nuclei. Using these data, CMS had observed several signatures of the quark–gluon plasma, including the imbalance between the momenta of each jet of particles produced in a pair, the suppression (“quenching”) of particle jets in jet–photon pairs and the “melting” of certain composite particles. In addition to lead–lead collision data (two data sets from 2010 and four from 2011), CMS has also provided eight sets of reference data from proton–proton collisions recorded at the same energy.

The open data are available in the same high-quality format that was used by the CMS scientists to publish their research papers. The data are accompanied by the software that is needed to analyse them and by analysis examples. Previous releases of CMS open data have been used not only in education but also to perform novel research. CMS is hopeful that communities of professional researchers and amateur enthusiasts as well as educators and students at all levels will put the heavy-ion data to similar use.

“Our aim with releasing CMS data into the public domain via the Creative Commons CC0 waiver is to preserve our data and the knowledge needed to use them, in order to facilitate the widest possible use of our data,” says Kati Lassila-Perini, who has led the CMS open-data project since its inception in 2012. “We hope that those outside CMS will find these data as fascinating and valuable as we do.”

CMS has committed to releasing 100% of the data recorded each year after an embargo period of ten years, with up to 50% of the data being made available in the interim. The embargo allows the researchers who built and operate the CMS detector adequate time to analyse the data they collect. With this release, all of the research data recorded by CMS during LHC operation in 2010 and 2011 is now in the public domain, available for anyone to study.

You can read more about the release on the CERN Open Data portal:

LS2 Report: Beams circulate in the PS Booster

Tue, 12/01/2021 - 11:27
LS2 Report: Beams circulate in the PS Booster Anaïs Schaeffer anschaef Tue, 01/12/2021 - 10:27

If you follow CERN on social media, you probably saw back in December that the first beam had been injected into the PS Booster (PSB), thus connecting the machine for the first time to the new Linac4.

This is a crucial milestone for the LHC Injectors Upgrade (LIU) project and an extraordinary accomplishment for all the teams involved in the PSB metamorphosis. “We changed almost everything in the Booster during LS2; it is basically a new accelerator that we turned on at the beginning of December. It was a remarkable achievement and a testament to the excellent preparatory work done by all equipment groups to see that practically everything was working as expected,” says Bettina Mikulec, who leads the operations team for the PS Booster and Linac4.

But the commissioning of the Booster is not as easy as turning on a TV. It is a lengthy and ongoing process. “In December, the brand-new state-of-the-art injection system was commissioned progressively and low-intensity beams were first guided to the very entrance of the accelerator, then injected into each one of the Booster’s four rings*,” explains Gian Piero Di Giovanni, LIU project leader for the PS Booster. “We managed to have beam circulating systematically for several hundred milliseconds, which is already a great success.”

Still, many settings have to be refined, and the operators must take ownership of their new machine. “The theoretical model developed for the upgraded Booster now gives a better description of the machine. This allows us to be precise in our tuning, and to get the most out of the accelerator,” adds Mikulec.

The Booster currently receives beams from Linac4 at the energy of 160 MeV; its job is to accelerate them up to 2 GeV. “The Booster’s new radiofrequency acceleration system is currently being commissioned. Once this crucial step is completed, we will be able to accelerate protons in the machine,” says Di Giovanni. This should happen in the coming weeks. In March, the first beams will then be extracted from the Booster into the PS. But that is another story.


*The PS Booster is made up of four superposed synchrotron rings that are fed by Linac4. Depending on the beam schemes “requested” by the accelerators downstream, only some or all of the four rings receive beams.

ALICE takes leap forward with major new installation

Mon, 11/01/2021 - 16:56
ALICE takes leap forward with major new installation thortala Mon, 01/11/2021 - 15:56

Following the return of the Time Projection Chamber (TPC) and the Miniframe to the ALICE detector cavern in recent months, ALICE ended what was a very productive year on a high note: the collaboration successfully mounted the Muon Forward Tracker (MFT) subdetector in the TPC, inside the experiment’s main detector. The two MFT barrels were transported to the ALICE site and lowered into the 60 m deep cavern in the first week of December. The subdetector was then positioned to tenth-of-a-millimetre precision inside a carbon composite cage at the very centre of the TPC – a challenging undertaking. This achievement crowns more than five years of design, construction, and qualification tests conducted by a dozen research institutes in Europe, Asia and South America.

The MFT is a 0.5 m² pixel detector comprising more than 1000 silicon sensors placed on the detector’s C-side. The silicon pixel sensors, called ALPIDE, were developed by the Inner Tracking System (ITS) and MFT project teams. Each chip houses half a million pixels in an active area of 4.5 cm², a very high pixel density that translates into enhanced resolution for high-precision measurements of particle tracks. The ALICE detector will thus be equipped to tackle the rich physics opportunities offered by the increased luminosity of the future LHC runs.

The MFT will complement the current muon spectrometer, which detects muon pairs generated by the proton–lead ion collisions and reconstructs the vertexes from which these pairs originate. The 5 mm position resolution of the MFT’s silicon sensors will, for example, enable muon pairs originating from charm hadron decays to be distinguished from those coming from bottom hadrons – a crucial step towards the analysis of the respective properties of charm and bottom quarks. This in turn allows ALICE scientists to delve deeper into quarkonia – bound states of charm and anti-charm or bottom and anti-bottom quarks – and its interaction with the quark–gluon plasma produced in high-energy heavy-ion collisions at the LHC.

The successful installation of the MFT detector inside the ALICE detector represents a major milestone on the road of LS2 upgrades, as Luciano Musa, spokesperson of the ALICE collaboration, explains: “The full MFT detector operated for several months above ground before its installation, which determined that it fully meets the experiment’s requirements. Thanks to the thorough preparations, the installation of the MFT at the heart of the ALICE detector, a very complex and delicate operation, went very smoothly. This is a big milestone for us, and a nice ending to a difficult year.” Next step on this road: the commissioning of the MFT and its integration into the ALICE operational systems, which will prepare the whole detector for the first beam of the LHC Run 3 and the physics challenges it will bring.

Materials that matter

Fri, 08/01/2021 - 20:36
Materials that matter Linn Tvede thortala Fri, 01/08/2021 - 19:36

Jorge Guardia-Valenzuela is a bit of an outlier in the world of CERN’s knowledge transfer: this material science engineer started his journey at CERN in direct collaboration with the Knowledge Transfer group, as a technical student working on applications of CERN technologies to industry and conducting his master’s thesis. As part of his work, he tailored a material initially developed for CERN collimators into a thermal management application that could be used in industry.

Jorge then left the Knowledge Transfer group to develop and characterise new graphite-matrix composites for future collimators through CERN’s Doctoral Student Programme, but he never stopped discussing possible applications of the material with external companies. “Working with industry, learning more about their needs and challenges has been very valuable, as it allowed me to integrate new collimator materials into diverse devices. Thanks to the guidance of the Knowledge Transfer group, I have been involved in promising industrial studies, often focused on heat dissipation in electronics.”

The Knowledge Transfer group is not only about finding applications of CERN technologies to industry; it aims to instil a taste for high-tech entrepreneurship in scientists, as well as in students through the CERN Entrepreneurship Student Programme (CESP). As a technical adviser for the programme, Jorge had the opportunity to support and guide a team of students from the Norwegian University of Science and Technology (NTNU) in marketing the novel thermal management material he developed. “I feel motivated by the idea that my research creates a real impact in society, be it through improving existing products or creating new ones,” Jorge explains.

Looking ahead, a new R&D project is set to take place at CERN, with the goal of upscaling the production of the materials in order to promote their use in future particle physics facilities, as well as for commercial thermal management applications.

Learn more about how to get involved in CERN’s knowledge transfer activities here.



Computer Security: CEO fraud

Fri, 08/01/2021 - 12:54
Computer Security: CEO fraud The Computer Security Team anschaef Fri, 01/08/2021 - 11:54

Have you ever heard of “CEO fraud”? It is a social engineering method to extract money from a company, playing on several psychological techniques to make people stop thinking consciously:

  • Fear, guilt and shame, i.e. making a threat to you or your family (“I know what you did last summer and will tell your family if you don’t…”). Under that pressure, you will just comply as your fear adverse consequences if you don’t;
  • Flattery, i.e. luring your ego, pride or complacency (and narcissism?) into complying;
  • Seniority and respect, i.e. blindly obeying because you are instructed by someone much more senior than you, you are just a little cog in the machine.

The CEO fraud plays the “seniority” card: “I am the CEO and you will do as I wish”. Full stop. And such a targeted CEO fraud attack has been run against CERN by abusing the name of our DG and spoofing her e-mail address(1). It all happened in the morning of October 19 when several people in the CERN hierarchy or with budget responsibilities received the following message:

Note that the “From:” address has been spoofed. The so-called header information(2) of that e-mail – something like the address on the envelope of a letter – indicates that the mail does not come from CERN (but from “”) and that all replies would go the e-mail address “”:

The trap has been set. The attacker just needs someone to reply… Bingo:

With bi-directional communication established, the attacker can now engage, using their social engineering powers, and try to convince the victim to comply with their wishes (once more, the “From:” address is fake, replies go to the aforementioned Gmail address):

Unlike in other similar cases, the attacker does not even play the “secrecy”-card and requests 100% confidentiality of this communication (i.e. “This is a highly confidential transaction and should remain between you and me”). Instead, the attacker explains why other alternatives (the treasurer) are not an option. Thanks to the power of the alleged DG, the scam works:

There we go:

Fortunately, this scam was spotted by other people having also received the initial e-mail. Some noticed – as you can too! – that when trying to reply to this fraudulent mail the new recipient is indeed NOT Fabiola:

So, the fact that they reported the scam e-mail to enabled CERN to:

  • block similar e-mails from entering CERN mailboxes as well as blocking the attacker’s e-mail address;
  • identify other people who had received the scam and warn them;
  • ensure that the attacker’s IBAN was flagged and blocked from being used at CERN.

This is why vigilance and suspicion is helpful. Please don’t let yourself be impressed (or intimidated!) by seniority. By CEO power. By a strong voice. Similarly, please don’t let yourself be ashamed, harassed or intimidated by e-mails trying to create fear, guilt or shame. These are usually scams too. Instead, in particular in the event of any doubt, involve your hierarchy, the CERN Internal Audit Service or They are here to support and help you! Your early notification helps protect CERN when other means fail. Better to ask than to be sorry…


(1) As detailed in another Bulletin article, there is no simple defence against e-mail address spoofing. E-mail sender addresses, like sender addresses on normal postal envelopes, can easily be faked…

(2) In Outlook, you can access this header information by opening the e-mail, clicking on the small arrow to the right of “Tags” and then looking at “Internet headers”. In Thunderbird, open the mail and go to “View > Headers > All”. Similarly for Apple Mail: “View > Message > All Headers”.


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

Relive 2020 at CERN

Fri, 18/12/2020 - 11:59
Relive 2020 at CERN thortala Fri, 12/18/2020 - 10:59


As this extraordinary year draws to a close, here is a chance to look back on the highlights of 2020.

From the awakening of CERN’s new linear accelerator Linac4 to major upgrades across the accelerator complex and detectors, it has been a year of change to the CERN infrastructures.

In the midst of a global pandemic, CERN scientists joined forces with experts in healthcare, drug development, epidemiology and emergency response in the fight against COVID-19.

Yet, despite the year’s challenges, the CERN community produced many beautiful physics results, from the discovery of a new tetraquark to the first indications of a rare Higgs boson process and the opening of an avenue for high-precision studies of the strong force.

This video will take you on a journey through key moments of 2020 at CERN. Enjoy!

CMS sets new bounds on the mass of leptoquarks

Thu, 17/12/2020 - 12:03
CMS sets new bounds on the mass of leptoquarks Ana Lopes abelchio Thu, 12/17/2020 - 11:03 The CMS detector (Image: CERN)

At the most fundamental level, matter is made up of two types of particles: leptons, such as the electron, and quarks, which combine to form protons, neutrons and other composite particles. Under the Standard Model of particle physics, both leptons and quarks fall into three generations of increasing mass. Otherwise, the two kinds of particles are distinct. But some theories that extend the Standard Model predict the existence of new particles called leptoquarks that would unify quarks and leptons by interacting with both.

In a new paper, the CMS collaboration reports the results of its latest search for leptoquarks that would interact with third-generation quarks and leptons (the top and bottom quarks, the tau lepton and the tau neutrino). Such third-generation leptoquarks are a possible explanation for an array of tensions with the Standard Model (or “anomalies”), which have been seen in certain transformations of particles called B mesons but have yet to be confirmed. There is therefore an additional reason for hunting down these hypothetical particles.

The CMS team looked for third-generation leptoquarks in a data sample of proton–proton collisions that were produced by the Large Hadron Collider (LHC) at an energy of 13 TeV and were recorded by the CMS experiment between 2016 and 2018. Specifically, the team looked for pairs of leptoquarks that transform into a top or bottom quark and a tau lepton or tau neutrino, as well as for single leptoquarks that are produced together with a tau neutrino and transform into a top quark and a tau lepton.

The CMS researchers didn’t find any indication that such leptoquarks were produced in the collisions. However, they were able to set lower bounds on their mass: they found that such leptoquarks would need to be at least 0.98–1.73 TeV in mass, depending on their intrinsic spin and the strength of their interaction with a quark and a lepton. These bounds are some of the tightest yet on third-generation leptoquarks, and they allow part of the leptoquark-mass range that could explain the B-meson anomalies to be excluded.

The search for leptoquarks continues.


Read more on the CMS website and the Courier website.

CERN introduces proximity detecting device for personnel

Tue, 15/12/2020 - 10:40
CERN introduces proximity detecting device for personnel thortala Tue, 12/15/2020 - 09:40

Rapid and comprehensive contact tracing has proven to be an effective way of breaking chains of transmission of COVID-19, and continues to play a central role as the pandemic evolves. At CERN, contact tracing has been in place since the start of the pandemic through a time-consuming interview-based procedure relying on human memory, with all its inherent imperfections, and the delays it entails in identifying possible transmission to close contacts. Furthermore, with the pandemic likely to be with us for some time, the current approach, which places a huge burden on the Medical Service, is not sustainable over the long-term. The new approach is more precise, and delivers more timely information to help CERN break the chains of transmission.

As of next year, CERN’s contact tracing will be improved through the introduction of the Proximeter, a device that everyone with a CERN ID will be required to carry while on-site. Its main purpose is to improve CERN’s response to the challenges of COVID-19, making the Laboratory a safer place for everyone. For the system to work effectively, each and every one of us will need to wear the device while at work. As its name implies, the Proximeter is a proximity sensing device.  It will vibrate to warn its carriers when they move to within two metres of each other for more than 30 seconds, allowing them to move to a safe distance apart. The Proximeter transmits details of the encounter every 15 minutes to a central database in CERN’s main computer centre, protected with state-of-the-art encryption and authentication mechanisms.

The decision to deploy the Proximeter as CERN’s contact tracing device was taken by the Enlarged Directorate (ED) following extensive consultations across the Organization. The ED concluded that the Proximeter enables us to put health first whilst minimizing the intrusion into privacy.

Combating the spread of COVID-19 is the primary objective in rolling out the Proximeter, but privacy has been carefully considered. There is no location tracking – just proximity detection. The Proximeter only knows where it is with respect to other Proximeters. It does, however, know that information to an accuracy far better than that of mobile-phone-based apps, which makes it very good at telling its holders when they are getting too close, while keeping their whereabouts confidential.

When a Proximeter transmits data to the Medical Service’s database, that data is limited to the serial number of the device, and of the devices it has been close to, along with the time and duration of the encounter. Personal data linking the holder to the device number is stored in separate databases, and can only be matched by the Medical Service through a strictly monitored protocol. Data is protected at all times with state-of-the-art encryption and authentication mechanisms, and is held for 14 days before being deleted.

Proximeter data will not be processed automatically: only the data of those who call the Medical Service to declare symptoms, or a positive test, will be looked at. The information on encounters will then be discussed between those concerned and the Medical Service to determine whether or not there is a risk of transmission. Phone-based apps, on the other hand, simply notify the carrier of a close contact with an infected person, requiring self-isolation without a full understanding of the context of the encounter. Deployment of the Proximeter will allow the Medical Service to determine the right course of action following an interview with the persons concerned, which will determine the level of potential contamination, for example by establishing whether masks were being worn.

As of this week, if you are on-site, you may start to see people carrying Proximeters as a pilot run gets underway. Some 950 devices have already been delivered to CERN, and are being deployed among members of key units, such as the CERN Fire and Rescue Service and the Medical Service. Full-scale deployment will begin in January, with details to be communicated when we return to work after the end-of-year break. This will allow us to integrate lessons learned from the pilot period in the general roll-out. The obligation to carry a Proximeter while on-site will begin in March and continue until the pandemic is over. The regulatory framework governing the use of Proximeters will be defined in the CERN COVID-19 health and safety instructions, and published on CERN’s coronavirus information webpages. The FAQ on those pages will also be updated to address any questions you may have about the use of the Proximeter. A training course on the functioning and use of the Proximeter will also be available in January.

LS2 Report: Review of a rather unusual year

Mon, 14/12/2020 - 12:24
LS2 Report: Review of a rather unusual year Anaïs Schaeffer anschaef Mon, 12/14/2020 - 11:24

2020 is coming to an end... and what a year it has been. It remains to be seen what 2021 has in store for us... but let’s forget about coronavirus for a moment, and take a look at what’s going on at CERN’s accelerator complex. In spite of the obstacles, and thanks to the hard work of all the teams involved, the upgrade work being carried out during Long Shutdown 2 (LS2) has continued this year, and several important milestones have been reached.

On 31 January, a new kicker magnet was installed in the Proton Synchrotron (PS). After LS2, the PS Booster will supply it with particles at an energy of 2 GeV, compared with 1.4 GeV previously, and the PS needed this new magnet, as well as a new septum magnet (installed at the end of June), to be able to cope with this increase in the injection energy. In June, two beam dumps were also installed in the accelerator.

On 3 July, the LS2 accelerator coordination team handed over the PS Booster to the Operations group. Linac 4 and the PS Booster thus became the first two accelerators to be recommissioned, 18 months after the start of LS2.

At the LHC, as part of the DISMAC (Diode Insulation and Superconducting MAgnets Consolidation) project, reinforcement of the electrical insulation of the accelerator’s 1232 diodes has been completed. The final interconnection was closed on 3 August.

Also in August, low-energy negative hydrogen ion (H−) beams passed through the first section of Linac 4 for the first time since its connection to the Booster. On 20 August, the first beams at the nominal energy of 160 MeV passed through the whole machine to a special beam dump at the other end and, the following month, beams reached the beam dump just upstream of the Booster.

In September, the new external beam dumps of the LHC were successfully installed in their respective caverns.

At ELENA, the deceleration ring downstream of the AD, a beam of H− ions reached the GBAR and ALPHA experiments in October, marking the completion of the installation of new transfer lines from the new decelerator. Also in October, the “new” HIE-ISOLDE (High Energy and Intensity Isotope mass Separator On-Line) received its first beam since it was shut down in November 2018: a stable neon beam from an independent source, injected into the machine to allow adjustments to be carried out.

The new transfer line connecting the ELENA ring (behind the wall on the right) to the GBAR experiment (left). (Image: CERN)

The Proton Synchrotron and the Super Proton Synchrotron were handed back to the Operations group on 23 October and 4 December respectively.

On 15 November, the cool-down of sector 4-5, the first sector to be cooled, was successfully completed. The sector was cooled with superfluid helium to a temperature of 1.9 K (-271.3 °C), its nominal operating temperature. The whole LHC will be operating under its nominal cryogenic conditions by spring 2021.

New equipment developed for the High-Luminosity LHC (HL-LHC) has also been installed in the collider over the course of the year (see here and here). At the LHC’s large experiments, which have been particularly impacted by the pandemic, work is continuing, detector by detector, optical fibre by optical fibre.

An update on the schedule
The new schedule for LS2, approved by the CERN Management on 23 October, anticipates that the first low intensity test beams will circulate in the LHC at the end of September 2021. Run 3 of the LHC will start in early 2022. As for the LHC’s injectors, they are gradually being started up this month. The many experiments at ISOLDE and the PS-SPS complex (except for those using ion beams) will therefore be able to start taking data as of summer 2021. No changes have been made to the schedule beyond 2022. The third long shutdown (LS3) will begin at the start of 2025 and end in mid-2027.

*** We would like to take the opportunity of this final “LS2 Report” of the year to wish you
a very happy festive season. Take care and see you next year! ***

Registration is open for Beamline for Schools 2021

Fri, 11/12/2020 - 13:48
Registration is open for Beamline for Schools 2021 thortala Fri, 12/11/2020 - 12:48

Continuing its successful seven-years run, Beamline for Schools is ready to kick off the 2021 edition. This physics competition offers high-school students the unique opportunity to carry out an experiment at CERN or in a partner research laboratory. Beamline for Schools has become increasingly popular over the past seven years, with more than 11000 students from around the world having taken part.

The competition is open to teams of five students or more, aged 16 and over, accompanied by at least one adult supervisor or “coach”. To participate, teams should think of a simple, creative experiment and submit a written proposal and a short video proposal. The submission deadline for the 2021 edition is 15 April 2021. The task may seem challenging, or even intimidating, but teams can draw inspiration from previous years’ proposals. The Beamline for Schools team at CERN and the contact person in each country or region stand ready to answer questions and provide guidance.

Each year, two of the teams that compete are selected by a committee of experts to conduct their experiments at a particle physics facility. In 2021, the CERN test-beam area will still be under scheduled maintenance and so cannot host experiments. The experiments will thus be performed at DESY in Hamburg, Germany. DESY is a world-leading accelerator centre and Germany’s national laboratory for particle physics, accelerators and photon science. It offers particle beams and infrastructure where a very wide range of experiments in particle physics, detector development and multidisciplinary science can be conducted.

All participants will receive a certificate. Shortlisted teams will receive a T-shirt and a special prize. Each winning team - up to nine members and two coaches - will be invited, all expenses paid, to DESY for between 10 and 15 days to perform their experiment.

Learn more about the Beamline for Schools competition and registration at

25 years of service at CERN - 2020

Wed, 09/12/2020 - 12:30
25 years of service at CERN - 2020 HR department thortala Wed, 12/09/2020 - 11:30

In this particular year, it is unfortunately not possible to hold the traditional congratulatory ceremony for our staff members who have reached 25 years of service. We extend our warmest thanks to the following 54 staff members for this milestone in their careers, and wish them the best for the future at CERN!

Dr. Benedikt Michael ATS-DO

Mr. Modena Michele ATS-DO

Dr. Bruning Oliver ATS-DO

Mr. Arduini Gianluigi BE-ABP

Ms. Pirotte Florence BE-ASR-SU

Mr. Schneider Gerhard BE-BI-ML

Mr. Peryt Maciej BE-CO-APS

Mr. Sowinski Piotr BE-CO-APS

Mr. Bau Jean-Claude BE-CO-HT

Mr. Havart Frederic BE-ICS-CSE

Mr. Martel Pedro BE-ICS-TI

Mr. Epting Uwe BE-ICS-TI

Mr. Haase Matthias BE-RF-IS

Dr. Vandoni Giovanna BE-RF-SRF

Mr. Pym John DG-TMC

Mr. Losito Roberto EN

Ms. Foraz Katy EN-ACE

Mr. Chemli Samy EN-ACE

Ms. Mallon Amerigo Sonia EN-ACE-AMM

Dr. Peon Guillermo EN-CV-GEM

Dr. Mathot Serge EN-MME-DI

Mr. Jones Mark EN-SMM-HPA

Dr. Di Mauro Antonio EP-AID-DT

Dr. Barney David EP-CMX

Dr. Gill Karl Aaron EP-CMX-DA

Dr. Capeans Garrido Maria EP-CMX-SCI

Mr. Lesenechal Yannick EP-DT-CO

Dr. Kluge Alexander EP-ESE-FE

Dr. Kloukinas Konstantinos EP-ESE-ME

Mr. Kaplon Jan EP-ESE-ME

Dr. Snoeys Walter EP-ESE-ME

Dr. Palestini Sandro EP-NU

Ms. Curdy Cecile HR-CB

Ms. Lara Arnaud Cristina IPT-PI-RI

Dr. Gillies James IR-SPE

Mr. Sallaz Eric IT-CF-FPP

Dr. Duellmann Dirk IT-SC

Dr. Desirelli Alberto PF-IN-QM

Ms. Boureau Anne PF-OP-ATT

Ms. Carvalho Correia Paula SMB-SSL

Mr. Grawer Gregor TE-ABT-EC

Dr. Bremer Johan TE-CRG-CI

Mr. Herblin Lionel TE-CRG-OP

Mr. Cravero Jean-Marc TE-EPC-FPC

Mr. Michels Olivier TE-EPC-HPC

Mr. Hudson Gregory TE-EPC-HPM

Mr. Coelingh Gert-Jan TE-MPE-EE

Dr. Bottura Luca TE-MSC

Mr. Parma Vittorio TE-MSC-CMI

Mr. Luzieux Sebastien TE-MSC-LMF

PROF. Garcia Perez Juan Jose TE-MSC-MM

Dr. Ballarino Amalia TE-MSC-SCD

Mr. Jacquemod Andre TE-MSC-SCD

Dr. Mangano Michelangelo TH-SP

SPS key back in the hands of the Operations group

Wed, 09/12/2020 - 11:28
SPS key back in the hands of the Operations group anschaef Wed, 12/09/2020 - 10:28

Almost exactly two years ago, all SPS equipment was switched off and responsibility for the machine was handed from the Operations (OP) group in the Beams (BE) department to the Accelerator Coordination and Engineering (ACE) group in the Engineering (EN) department.

Despite the SPS not accelerating particles, the tunnel was buzzing with action during Long Shutdown 2 (LS2). Many parts of the machine were taken apart and renewed or consolidated with the aim of increasing its performance and reliability.

On 4 December 2020, exactly as scheduled, members of the EN-ACE group concluded their task of coordinating, in close collaboration with all the equipment and service groups, the LS2 activities by handing the key of the upgraded SPS back to BE-OP, signalling the start of the hardware commissioning period. During this nine-week period, the operations teams, working closely with the equipment experts, will make sure every piece of equipment and its associated software are working according to specifications. Then there will be a six-week cold check-out period, where the machine will run as if beams were being produced, but without particles, checking that everything is working in harmony like a finely tuned orchestra.

On 12 April 2021, the SPS will have to be ready to receive the first beams from the PS to commission all beams required for physics, so that the experimentalists in the SPS North Area can resume their physics data taking on 12 July 2021.

CERN intensifies collaboration with Brazil through scientific agreement with leading research centre

Tue, 08/12/2020 - 11:12
CERN intensifies collaboration with Brazil through scientific agreement with leading research centre Thomas Hortala thortala Tue, 12/08/2020 - 10:12 CERN Director for Accelerators and Technology Frédérick Bordry (right) and CNPEM Director General José Roque da Silva (left, in front of the SIRIUS light source hall) signing the Collaboration Agreement

Brazil further strengthened its ties with CERN through the signature, on 4 December 2020, of a wide-ranging scientific and technological collaboration agreement between the Brazilian Center for Research in Energy and Materials (CNPEM) and the Organization. This agreement is particularly timely as the process for Brazil to become an Associate Member State of CERN progresses.

Frédérick Bordry, Director for Accelerators at CERN, met CNPEM Director-General José Roque da Silva virtually to sign the agreement, which establishes a framework for collaboration in research and development in areas of mutual interest. These include particle accelerator technology, magnet design and the study of superconducting materials. “I am delighted to sign this collaboration agreement. For 30 years, Brazil has been a strong partner in CERN’s scientific activities. The signing of this new agreement will enhance our collaboration in scientific research, training, innovation and knowledge-sharing in the field of accelerator technology,” explained Frédérick Bordry, adding that “CNPEM and Brazil have many proven skills and talent in this area which will bring mutual benefits and motivate industrial partners.”

CNPEM is a multidisciplinary research centre overseen by the Brazilian Ministry of Science, Technology and Innovations. Its expertise in the field of accelerator physics was recently bolstered by the design, building and commissioning of the SIRIUS synchrotron, a state-of-the-art fourth-generation light source that will assist the centre in probing the properties of various materials. Although the purpose of SIRIUS differs significantly from that of the CERN accelerator complex, the technology and engineering behind the facilities are of the same nature, which heralds fruitful exchanges between the two institutions.

This agreement could foster, in particular, joint projects in fields that are relevant for the Future Circular Collider (FCC) feasibility study, such as superconductivity, as well as the long-term involvement of Brazilian industry in CERN activities in the context of Brazil’s potential accession as an Associate Member State of CERN.

ALICE collaboration opens avenue for high-precision studies of the strong force

Tue, 08/12/2020 - 11:10
ALICE collaboration opens avenue for high-precision studies of the strong force mailys Tue, 12/08/2020 - 10:10 An artist’s impression of the ALICE study of the interaction between the rarest of the hyperons, Omega (Ω) hyperon (left), which contains three strange quarks, and a proton (right). (Image: CERN)

The collaboration shows how proton–proton collisions at the Large Hadron Collider can reveal the strong interaction between composite particles called hadrons.

In a paper published today in Nature, the ALICE collaboration describes a technique that opens a door to high-precision studies at the Large Hadron Collider (LHC) of the dynamics of the strong force between hadrons.

Hadrons are composite particles made of two or three quarks bound together by the strong interaction, which is mediated by gluons. This interaction also acts between hadrons, binding nucleons (protons and neutrons) together inside atomic nuclei. One of the biggest challenges in nuclear physics today is understanding the strong interaction between hadrons with different quark content from first principles, that is, starting from the strong interaction between the hadrons’ constituent quarks and gluons.

Calculations known as lattice quantum chromodynamics (QCD) can be used to determine the interaction from first principles, but these calculations provide reliable predictions only for hadrons containing heavy quarks, such as hyperons, which have one or more strange quarks. In the past, these interactions were studied by colliding hadrons together in scattering experiments, but these experiments are difficult to perform with unstable (i.e. rapidly decaying) hadrons such as hyperons. This difficulty has so far prevented a meaningful comparison between measurements and theory for hadron–hadron interactions involving hyperons.

Enter the new study from the collaboration behind ALICE, one of the main experiments at the LHC. The study shows how a technique based on measuring the momentum difference between hadrons produced in proton–proton collisions at the LHC can be used to reveal the dynamics of the strong interaction between hyperons and nucleons, potentially for any pair of hadrons. The technique is called femtoscopy because it allows the investigation of spatial scales close to 1 femtometre (10−15 metres) – about the size of a hadron and the spatial range of the strong-force action.

This method has previously allowed the ALICE team to study interactions involving the Lambda (Λ) and Sigma (Σ) hyperons, which contain one strange quark plus two light quarks, as well as the Xi (Ξ) hyperon, which is composed of two strange quarks plus one light quark. In the new study, the team used the technique to uncover with high precision the interaction between a proton and the rarest of the hyperons, the Omega (Ω) hyperon, which contains three strange quarks.

“The precise determination of the strong interaction for all types of hyperons was unexpected,” says ALICE physicist Laura Fabbietti, professor at the Technical University of Munich. “This can be explained by three factors: the fact that the LHC can produce hadrons with strange quarks in abundance, the ability of the femtoscopy technique to probe the short-range nature of the strong interaction, and the excellent capabilities of the ALICE detector to identify particles and measure their momenta.”

“Our new measurement allows for a comparison with predictions from lattice QCD calculations and provides a solid testbed for further theoretical work,” says ALICE spokesperson Luciano Musa. “Data from the next LHC runs should give us access to any hadron pair.”

“ALICE has opened a new avenue for nuclear physics at the LHC – one that involves all types of quarks,” concludes Musa.

Further information:



Photos of ALICE detector


Videos of ALICE detector

Outside drone footage

Views inside the detector


Background content

ALICE experiment

Recreating Big Bang matter on Earth

Reinstalling the revamped ALICE Miniframe

Tue, 08/12/2020 - 10:05
Reinstalling the revamped ALICE Miniframe thortala Tue, 12/08/2020 - 09:05

This picture shows the ALICE Miniframe being reinstalled on the detector in mid-November 2020, after a two-year-long stay at the surface for upgrades.

Weighing in at 14 tonnes and measuring 12 metres long, the Miniframe is anything but “mini”: it is a giant “plug” – a large metallic support structure, installed in front of the A-side of the ALICE Time Projection Chamber (TPC) and sitting partially in the L3 magnet. It has supported ALICE’s systems since the detector’s debut, carrying the services for the TPC and ITS (Inner Tracking System), such as power supply, cooling, gas, detector control, detector safety, trigger and data acquisition. It also houses the ALICE forward detectors, FIT-A (Fast Interaction Trigger A), the ALICE RB24 beampipe, and the compensator magnet. The Miniframe was designed to be easily removable in case the TPC needed to be extracted during long shutdown (LS) periods.

This came in handy during LS2, as the TPC was temporarily removed from the cavern for upgrades. In January 2019, the Miniframe was brought to the SX2 surface hall, where it received new services and patch panels for the new ALICE tracker, the ITS2, including kilometres of new cables for the ITS2 and TPC. The support structures and cable trays were re-engineered to accommodate the cables, including the 7000 optical fibres needed to allow continuous readout from the TPC and ITS2.

The upgrades were completed just in time for the reinstallation in November 2020, when the fully refurbished Miniframe was lowered back into the cavern and inserted in front of the detector. Since then, work has been continuing to connect the services, with a view to getting the TPC operating by the end of the year.

Rooted in society

Mon, 07/12/2020 - 16:51
Rooted in society Amy Bilton thortala Mon, 12/07/2020 - 15:51

Axel Naumann spearheads the development of one of CERN’s key digital tools, ROOT, which was originally designed for high-energy physics (HEP) and is now widely used in industry.

ROOT has been processing particle collision data since the time of the Large Electron–Positron Collider. What makes it stand out is its ability to detect anomalies in extremely vast datasets, and such anomalies may indicate new physics. This is just one feature that makes ROOT applicable beyond HEP. So far, ROOT has proven well suited to help protect commodity and financial markets from fraud, improve vaccine production, analyse large genomics datasets and improve aviation safety.

Naumann, a senior applied physicist in the Software Design for Experiments group (EP-SFT), collaborated closely with the Knowledge Transfer (KT) group to foster these applications. “We’ve always learned from our partners and vice versa, which allows the software to evolve.” This is particularly relevant given that ROOT is distributed under an open-source licence: “People can immediately contribute to and have an impact on the production of the code. This means that it can evolve to cover different needs.”

Collaborating with partners outside of HEP can also help Naumann and his team tap into additional resources for their work. “One of the earliest projects we had was with a potential start-up from the Norwegian University of Science and Technology (NTNU). The start-up needed to learn more about ROOT, and we agreed that someone from their team could come to CERN to code with us. After six months of working together, some of that code is still in production today. Through these exchanges, we gain a deeper understanding of the digital challenges that companies face and, with our expertise in data processing software, we are able to guide them on the best tools to use.”

Naumann sees this sharing of knowledge as inherent to CERN. “We are financed to do fundamental research and we should not forget that. Our job was not to invent the World Wide Web; it was to understand the nature of matter. However, it is always nice to be able to provide additional arguments for investing in fundamental science. We are financed by society. We should give back to society.”

Learn more about how to get involved in CERN’s Knowledge Transfer activities here.

Four CERN technical apprentices in the class of 2020

Fri, 04/12/2020 - 11:36
Four CERN technical apprentices in the class of 2020 Anaïs Schaeffer anschaef Fri, 12/04/2020 - 10:36

This year, due to COVID-19, CERN’s four final-year technical apprentices completed their training in a slightly unusual way. Like everyone at CERN, they had to work from home for several weeks, which, when you’re doing technical training, comes with a few added complications: “Some laboratory activities were obviously suspended or postponed, but online training sessions were added, and the apprentices were able to continue their classes via videoconference,” explains Virginia Prieto Hermosilla, who is in charge of the technical apprentice programme. “Everyone did their best and adapted to the situation. The CERN supervisors and external experts monitored the process and “visited” the apprentices via videoconference. This allowed the final-year students to progress with their individual practical coursework and to obtain their diplomas!”

Anthony Covini and Marco Travaini, electronics technicians, and Stefanie Alves and Loïc Gurtner, physics laboratory technicians, thus obtained their certificat fédéral de capacité (CFC) after four years of training at CERN. No mean feat in the present circumstances!

In addition, Anthony Covini and Loïc Gurtner were among the top mechatronics apprentices in Geneva and were awarded prizes by the Union industrielle genevoise (UIG). The prize-giving ceremony, traditionally held in December, has been postponed to next year.

At the start of the 2020-2021 academic year, five apprentices in their second year of training began their placements at CERN. Five apprentices in their first year have also been selected and will come to CERN next September, once they have completed their basic training at the Centre d’enseignement professionnel UIG-UNIA.

In 2020, the CERN apprentices were hosted by the BE-BI, BE-RF, EN-MME, EP-ESE, EP-DT, TE-CRG, TE-EPC, TE-MPE, TE-MSC and TE-VSC groups, as well as by the Hôpitaux universitaires de Genève (HUG) and the Haute école du paysage, d'ingénierie et d'architecture de Genève (HEPIA). The commitment of the various groups to CERN’s apprenticeship programme and the quality training and support provided by the supervisors undoubtedly contribute to the success of CERN’s apprentices.


*The CERN apprenticeship programme trains mechanical technicians, electronics technicians and physics laboratory technicians. It is coordinated by the TE department. For more information, please contact Virginia Prieto Hermosilla (TE-PPR).

Computer Security: CERN’s new first line of defence

Fri, 04/12/2020 - 11:24
Computer Security: CERN’s new first line of defence The Computer Security Team anschaef Fri, 12/04/2020 - 10:24

Christmas has come early this year for the Computer Security team and the Communication and Network group (IT-CS) in the form of hardware for a new outer perimeter firewall. This next-generation firewall is intended to boost performance and bandwidth as well as being a sophisticated means to better identify and protect against cyberattacks.

CERN’s outer perimeter firewall is the first line of defence protecting the Organization from any malicious or otherwise unwanted network traffic entering its general-purpose network. The firewall exposes to the internet selected computing services that need to be accessible from outside CERN, controls internet traffic from and to all user devices, and blocks malicious traffic. Due to an increasingly aggressive global cyberthreat landscape, it is imperative to strengthen our firewall’s cybersecurity protection and detection capabilities using modern and sophisticated prevention tools. Unfortunately, the firewall currently installed at CERN, with its protective features and its limited throughput, has become insufficient to support the Organization’s networking and protection needs.

Enter our Christmas present! CERN’s new outer perimeter firewall will correct these two drawbacks – limited bandwidth and limited protection capabilities – and provide a sustainable solution for the next seven plus years.

CERN’s new outer perimeter firewall. (Image: CERN)

On the hardware side, it will be able to digest, filter and control up to 200 Gb per second in uplink (i.e. leaving CERN) and downlink (i.e. entering CERN) traffic without any performance penalty. Its set-up is flexible, meaning that this total bandwidth can be adapted to CERN’s current and future needs and ramped up whenever necessary. Of course, hardware redundancy will guarantee high availability and spare CERN from connection problems in the event of one of the hardware chassis or their network connections failing. And the whole functionality will be integrated into the network automation software developed and used by IT-CS, to ensure that configurations are properly managed and can be changed easily and consistently.

On the computer security side, this new firewall benefits from advanced threat intelligence, which offers enhanced capabilities compared to traditional threat prevention services. Such threat intelligence services rely on security researchers to track down specific threat groups, ranging from cybercriminals to nation-state attackers, in order to produce detailed, up-to-date, specific indicators for detecting malicious attacks. Combined with the threat intelligence already available to CERN’s Computer Security team, this means sophisticated potential attacks will be automatically identified and malicious content automatically filtered before it can cause harm.

These advanced services also make it possible to enforce certain CERN Computing Rules (OC5) by blocking internet content that is considered to be inappropriate (e.g. pornographic or sexually explicit material, or sites that promote the abuse of both legal and illegal drugs) or offensive (e.g. websites promoting terrorism, racism, fascism or other extremist views that discriminate against people or groups of different ethnic backgrounds, religions or other beliefs, but not websites discussing controversial political or religious views) or violates applicable laws (e.g. sites that infringe copyright by illegally offering music, movies or other media for download). We still need to determine the extent to which such content should be blocked without overly restricting our academic liberties and freedom of communication. We would like to hear your thoughts on this – write to us at

In the next few months, the IT-CS experts and the Computer Security team will put this lovely Christmas gift of a new firewall into production – for a better first line of defence. And we want to spread the Christmas spirit by wishing you all a happy and healthy holiday season. Enjoy your time off, take care of yourself and your family, and stay safe and secure!


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