Subscribe to CERN News feed
Updated: 35 min ago

Ubuntu* - a powerful motto for an important experiment

Mon, 07/24/2017 - 11:35

The first African-led experiment has taken place at CERN, supported by UK researchers. Students and staff from the University of the Western Cape, South Africa, have investigated the isotope Selenium 70 using Isolde, CERN’s nuclear physics facility. (Video: Christoph Madsen/CERN)

The first African-led experiment has taken place at CERN. Students and staff from the University of the Western Cape (UWC) have investigated the isotope selenium 70 at CERN's Isolde facility.  The nucleus of this isotope is known to have two possible shapes, depending on its excitation state, and the team wanted to examine the relationship between shape and energy more closely.

South Africa joined the Isolde collaboration in March 2017 to benefit from HIE-Isolde’s beams of unstable, exotic particles – the country’s own nuclear physics facility has a source of stable beams.  The selenium 70 experiment, using Miniball, is the first to be approved.   

“We’re going to be accelerating a selenium beam into a platinum target,” explains PhD student Kenzo Abrahams, as the team configures the experiment around him.  "By colliding two nuclei, we will cause the excitation of the selenium 70 isotope, and by measuring the intensity of the gamma ray decay, we’ll know which shape has been excited.”

The UWC team, comprising masters and PhD students from the coulomb excitation group, led by Professor Nico Orce and supported by experiment co-lead, Professor David Jenkins from the University of York, certainly feel that they are blazing the way for other South African universities to submit proposals.  “The University of the Western Cape is a historically disadvantaged institution,” explains Nico, “we have team members from rural areas of the Eastern Cape, and others who live in townships.  I hope this experiment will have a domino effect, encouraging similar students and universities to aim for the top.”

Totalling 11 people, the experimental team is much larger than Isolde would normally welcome, but Nico was determined to give as many of his students as possible the opportunity to use one of the world’s best research facilities. 

Senamile Masango is a masters student, “this is my first time outside South Africa and it’s very exciting to be at CERN,” she says, “it’s every scientist’s dream to come to facilities like this!” 

Passionate about her subject, and highly motivated, Senamile is also well aware that she is an important role model, “you will hardly find any women doing physics in South Africa, and you will hardly find any black physicists.  Nico treats us all equally and he’s making us hungry to break every barrier.  We’re making history!”

“The skills that the students are learning at CERN are transformational.” says George O’Neill.  Having finished his PhD at Liverpool, George wanted the challenge of working in a new lab; he was attracted by both the facilities at UWC and Nico’s ethos, “Everyone in this group will go on to be a professor,” he adds.

David Jenkins is co-leading the experiment.  “I’ve worked with Nico for a long time and I’ve been teaching at his ‘Tastes of Nuclear Physics’ summer school for five years.  UWC has a real battle to get funding and Nico has jumped through so many hoops to get here.  I wanted to get them involved at Isolde and help build the research expertise in the team.”

If the extraordinary levels of energy and motivation demonstrated by the team are mirrored by the experimental results, then UWC is set to become a significant name in international nuclear physics.


*Ubuntu is a Xhosa word, translated by one of the team as “I am, because we are”.  It sums up the essence of this passionate and motivated group of young scientists.











Groundbreaking for an international neutrino experiment

Fri, 07/21/2017 - 16:45

This 11-meter high prototype at CERN will refine neutrino detector technology. The final DUNE detectors will be 20 times larger than this prototype and located in the new LBNF cavern in the United States. (Image: M. Brice, J. Ordan/CERN)

Today construction started on international mega-science facility which will employ the expertise of CERN to study the properties of neutrinos; ghostly fundamental particles that play by an unknown set of rules. The mile-deep experimental cavern is part of the Long Baseline Neutrino Facility, an international research center located in the United States that will eventually host four giant neutrino detectors. Researchers at CERN are currently building prototypes for these detectors and experimenting with new technologies that will enhance our pictures of these ghostly cosmic nomads.

“Some of the open questions in fundamental physics today are related to extremely fascinating and elusive particles called neutrinos.”, said CERN’s Director-General Fabiola Gianotti. “The Long-Baseline Neutrino Facility in the United States, whose start of construction is officially inaugurated with today’s ground-breaking ceremony, brings together the international particle physics community to explore some of the most interesting properties of neutrinos.’

This animation explains how the Long-Baseline Neutrino Facility will operate and supply neutrino beams to the Deep Underground Neutrino Experiment (DUNE) 1300 km from the source. (Video: Fermilab)

Neutrinos are among the most abundant fundamental particle in the universe, but little is known about them because they rarely interact with ordinary matter. Previous research has shown that neutrinos play by a different set of rules than all other particles, giving scientist hope that neutrinos might be the key to many lingering questions about the origin and evolution of the cosmos.

“Studying neutrinos could provide answers to some major mysteries in physics, such as why is the universe made entirely of matter and not antimatter,” said Filippo Resnati, a CERN researcher working at the Neutrino Platform. “We need a powerful neutrino beam and huge detectors if we want to measure and understand their properties.”

Neutrinos can traverse thousands of kilometers through rock and dirt before bumping into a terrestrial atom. While this aloofness makes neutrinos incredibly difficult to detect, it is also the principle underlying the Deep Under Ground Neutrino Experiment, which will be the first tenant in the new LBNF cavern. As neutrinos travel, they change their properties—a phenomenon which is little understood. The LBNF/DUNE Experiment will catch and measure neutrinos generated by a proton beam at Fermilab near Chicago, Illinois, before and after their 1300-kilometer subterranean sprint to Sanford Lab located in Lead, South Dakota. CERN’s Neutrino Platform is hosting an international community of researchers as they design and build prototypes for DUNE’s far detectors.

“Building and testing large prototypes is a necessary intermediary step for a project as massive as LBNF/DUNE,” said Marzio Nessi, the head of CERN’s Neutrino Platform. “We’re figuring out how to adapt the existing technology to thrive inside a house-sized detector. Once we’ve proven that it can work, we will then scale it up by a factor of 25 for the final DUNE detectors.”

Workers stand on scaffolding inside the DUNE prototype (ProtoDUNE). The metallic paneling will act as an expandable tank for the liquid argon, which will generate electrons and light when a particle interacts with the atoms of the liquid. (Image: Maximilien Brice, Julien Ordan/CERN)

The CERN prototypes are refining a detection technology originally developed by Carlo Rubbia, a Nobel prize winning physicist and former CERN Director General. Hatched panels of delicate wires and photon sensors record the electrical and light signals generated by neutrinos as they crash into argon atoms. This information enables physicists to triangulate the positions of neutrinos and measure their properties. These panels will be submerged in liquid argon in one prototype, and the other prototype will test a newer technology which uses electron multipliers suspended in argon vapor.

In addition to building and testing the detector prototypes for LBNF/DUNE, CERN will serve as the European hub for neutrino physicists working on research based in the United States and elsewhere in the world. CERN has a rich history of neutrino research and contributed to past discoveries, such as the direct observation of neutrino shape-shifting made by the OPERA experiment at Gran Sasso laboratory in Italy. CERN also provides the infrastructure for DUNE researchers to build and test their detectors using CERN’s test beam facility. This is the first-time CERN is joining projects located in the United States, with an active role designing final DUNE detectors and building the cryogenics infrastructure.

“Things are changing,” Resnati said. “CERN’s mission is to seek answers to the big questions in physics, and we want to be part of this worldwide quest for knowledge. We’re pulling together as a global community of physicists and making it happen.”

The groundbreaking ceremony at Sanford Lab in South Dakota starting at 11:20 pm CEST will be webcast. Watch the webcast!

Take a look at the CERN Neutrino platform with the eye of a drone. The huge red cube is the ProtoDUNE, a prototype for the DUNE detectors which will be installed in South-Dakota, USA, in the new Long-Baseline Neutrino Facility cavern. (Video: CERN)


HIE-ISOLDE: Nuclear physics gets further energy boost

Mon, 07/17/2017 - 15:16

This is the Miniball germanium array, which is using the first HIE-ISOLDE beams for the experiments described below (Image: Julien Ordan /CERN)

For the first time in 2017, the HIE- ISOLDE linear accelerator began sending beams to an experiment, marking the start of ISOLDE’s high-energy physics programme for this year.

The HIE-ISOLDE (High-Intensity and Energy upgrade of ISOLDE) project incorporates a new linear accelerator (Linac) into CERN’s ISOLDE facility (which stands for the Isotope mass Separator On-Line). ISOLDE is a unique nuclear research facility, which produces radioactive nuclei (ones with too many, or too few, neutrons) that physicists use to research a range of topics, from studying the properties of atomic nuclei to biomedical research and to astrophysics.

Although ISOLDE has been running since April, when the accelerator chain at CERN woke up from its technical stop over winter, HIE-ISOLDE had to wait until now as new components, specifically a new cryomodule, needed to be installed, calibrated, aligned and tested.

Each cryomodule is built in the CERN clean room before being installed one-by-one into the HIE-ISOLDE accelerator. This video shows work being done on the first cryomodule of the new HIE-ISOLDE instalation. The work was carried out in building SM18 in a specially dedicated clean room. (Video: Christoph Madsen/CERN)

Each cryomodule contains five superconducting cavities used to accelerate the beam to higher energies. With a third module installed, HIE-ISOLDE is able to accelerate the nuclei up to an average energy of 7.5 MeV per nucleon, compared with the 5.5 MeV per nucleon reached in 2016.

This higher energy also allows physicists to study the properties of heavier isotopes – ones with a mass up to 200, with a study of 206 planned later this year, compared to last year when the heaviest beam was 142. From 2018, the HIE-ISOLDE Linac will contain four of these cryomodules and be able to reach up to 10 MeV per nucleon.

“Each isotope we study is unique, so each experiment either studies a different isotope or a different property of that isotope. The HIE-ISOLDE linac gives us the ability to tailor make a beam for each experiment’s energy and mass needs,” explains Liam Gaffney, who runs the Miniball station where many of HIE-ISOLDE’s experiments are connected.

The HIE-ISOLDE beams will be available until the end of November, with thirteen experiments hoping to use the facility during that time – more than double the number that took data last year. The first experiment, which begins today, will study the electromagnetic interactions between colliding nuclei of the radioactive isotope Selenium 72 and a platinum target. With this reaction they can measure whether or not the nuclei is more like a squashed disc or stretched out, like a rugby ball; or some quantum mechanical mixture of both shapes. 

Eagle eye view of CERN

Thu, 07/13/2017 - 16:34

(Video: Christophe Madsen - Mike Struik/CERN)

Get a unique perspective of CERN by following this drone’s journey around the laboratory as it flies over the iconic Globe exhibition hall, the site of the ATLAS experiment at the LHC, through the magnet assembly facility, around the computing centre and across the border between France and Switzerland to the ALICE and CMS experiment, and much more.  

LHC experiments delve deeper into precision

Tue, 07/11/2017 - 16:22

Many results are being presented at the conference for the first time (Image: EPS-HEP 2017)

The world’s particle physics community is meeting this week in Venice (Italy) for the EPS International Conference on High Energy Physics. Dozens of new results from the full existing datasets of the Large Hadron Collider experiments are being presented for the first time.

In the last two years, the LHC has been running like a Swiss clock, delivering large amounts of collision data to the experiments, beyond the best expectations. With more luminosity (number of collisions) and more data, physicists are now able to explore the most fundamental interactions between particles with unprecedented sensitivity and precision.

The new results presented at EPS include detailed studies of the Higgs boson. Five years after the announcement of its discovery, physicists are now beginning to look at this very special particle with a magnifying glass, and gaining deeper insight into the way it interacts with other particles.

The level of precision achieved by the experiments with only a few percent of the total data sample expected from the LHC is impressive, said CERN Director General Fabiola Gianotti. “Particularly relevant is the exploration of the way the Higgs boson interacts with other particles, as physics beyond the Standard Model may alter these interactions.”

The Standard Model makes very specific predictions of how the Higgs boson interacts with the various particles. The first observations of the Higgs were based on measurements of its decay into other bosons (W, Z, g). Now, the ATLAS and CMS collaborations show how the Higgs decays directly to fermions such as quarks and leptons, the family of fundamental particles that make up matter.

The ATLAS Collaboration has reported the first evidence for the decay of the Higgs boson to a pair of bottom quarks, with a significance of 3.6 sigma. Although the Standard Model predicts this decay to occur in more than half of all Higgs boson decays, it is very difficult to distinguish from similar background processes.

"This evidence of the decay of the Higgs boson to bottom quarks constitutes an important milestone in the exploration of the Higgs boson properties,” said Karl Jakobs, Spokesperson of the ATLAS experiment. “It is important for the understanding of its short lifetime and for seeking indirect evidence for other, rarer decays.”

Following the recent evidence for the Higgs boson decaying to two tau leptons, the CMS collaboration presented the first observation of this decay by a single experiment, with a significance of 5.9 sigma.

This is of paramount importance to establishing the coupling of the Higgs boson to leptons and represents an important step towards measuring its couplings to third generation fermions, the very heavy copies of the electrons and quarks, whose role in nature is a profound mystery,” said Joel Butler, Spokesperson for the CMS collaboration.

Benefiting from the large data sample, LHC experiments can also test other properties of the Standard Model with higher precision. Thus, CMS presents the best measurement at the LHC of the weak-mixing angle, a key parameter of the Standard Model that establishes a firmly predicted relation between the masses of the W and Z bosons. The ATLAS collaboration also releases first evidence for an important but rare weak-interaction process in which a single top quark is produced together with a Z boson.

LHC experiments are also very active in the search of new physics beyond the Standard Model, and many new results for dark matter searches are being presented in Venice.

“So far we have been testing the simplest theoretical models of dark matter,” said CERN Director for Research and Computing, Eckhard Elsen. “We have now to investigate the more complicated scenarios, making the most of the precision that is now possible.”

High-level precision is also demonstrated for the strong interaction, as shown by the observation of a new particle with two charm quarks and a light quark, and in the increased precision in matter-antimatter asymmetry measurements achieved by LHCb, as well as in a wide range of results obtained from heavy ion collisions in all experiments. The ALICE collaboration notably presented one of the most precise measurements of the lifetime of the hypertriton, an exotic nucleus that contains a strange quark and is abundantly produced in collisions at the LHC.

An artist peeks behind CERN’s facade

Mon, 07/10/2017 - 13:32

Laura Couto Rosado is the 2017 winner of Arts at CERN’s ‘Collide Pro Helvetia’ residency award (Image: Sophia Bennett/ CERN)

For Laura Couto Rosado, a young Swiss designer, CERN is an ideal setting to draw inspiration from science for artistic research and to develop new works of art.

Laura Couto Rosado is the winner of 2017 Arts at CERN’s ‘Collide Pro Helvetia’ prize, which enables artists to spend three months at CERN, to be inspired by scientists and the world of science.

"My practice as a designer is inspired not only by natural phenomena, but also by the study of them, the science that leads to and the technologies that are based on them. I have always used the basic principles of physics to develop hybrid and intriguing design product," says Rosado, describing her work.

Rosado explains that she came to CERN with preconceived ideas for the project she will produce at the end of her residency. Now, one month into her time here, she says: “The knowledge I have acquired through my meetings with physicists exceeds all my expectations. They have driven me to focus my research in a more refined, subtle and creative way. For now, the best way for me to approach my project is to let the physicists express themselves by focusing on their own experiences, sharing their details and personal stories. Although that may be at the risk of losing the nuances of my own ideas."

Collide Pro Helvetia Award is organized by Arts at CERN is part of an on-going partnership with the Swiss Arts Council Pro Helvetia to offer Swiss artists, designers or artistic collectives a residency at CERN to explore the possibilities of the interactive devices and art in connection with scientific research.

You can find out more about Arts at CERN here. 

Accelerating particles - but not just for the LHC

Fri, 07/07/2017 - 15:00

Distribution of protons delivered by the accelerator chain to the different installations. (Image: Daniel Dominguez/CERN)

This week, the Large Hadron Collider (LHC) was in technical stop, but particles continued to circulate in the other accelerators. This is because the chain of four injectors that feed the LHC also supplies particles to myriad experiments across several experimental areas.

The journey of protons begins in the linear accelerator Linac 2, where they are boosted to one third of the speed of light.(Image: Maximilien Brice/CERN)

In fact, even when the LHC is running, the other experimental areas consume almost all the particles, as the diagram shows. The large collider uses less than 0.1% of the protons prepared by the injector chain. That’s primarily because the LHC is a storage ring: the same beams circulate in the ring for hours at a time, producing collisions with every circuit they complete. That’s not the case for CERN’s other machines, which send beams to fixed targets – an operation that has to be repeated every time data is taken.

All the protons start their journey in the linear accelerator Linac2, before being launched at a third of the speed of light into the Proton Synchrotron Booster (PSB). At that point, their paths diverge. 

More than half of the protons are sent to ISOLDE, a nuclear physics research facility. ISOLDE supplies various experimental areas hosting numerous experiments each year in fields ranging from fundamental physics to materials sciences and the production of isotopes for medical applications. Last year, ISOLDE supplied particles to 46 experiments. 

Miniball, one of the experimental set-ups of the nuclear research facility ISOLDE. The Isotope Mass Separator On-Line facility (ISOLDE) uses more than a half of the protons prepared in the CERN accelerator complex to carry out numerous experiments in fields ranging from fundamental physics to materials sciences and the production of isotopes for medical applications. (Image: Julien Ordan / CERN)

The remainder of the particles leaving the PS Booster go to the Proton Synchrotron (PS), which supplies three other experimental areas: the Antiproton Decelerator (AD), used for antimatter experiments, the East Area, which notably is home to the CLOUD experiment dedicated to studying the formation of clouds, and finally n_TOF, another nuclear physics facility.

The PS sends a small portion of its protons to the Super Proton Synchrotron (SPS), which in turn sends most of them to the North Area, where several fixed-target experiments including COMPASS and NA62 take data. Thus, in the end, the LHC receives only a tiny proportion of the particles that started the journey.

In 2016, CERN’s accelerator complex accelerated 134 billion billion protons (1.34 x 1020). This number corresponds to a minuscule quantity of matter, roughly equivalent to the number of protons in a grain of sand, but protons are so small that this amount is enough to supply all the experiments.

The LHC will resume operation tonight. After a week-end of tuning, the LHC physics programme should restart on Monday.

The Super Proton Synchrotron (SPS) is the last link in the accelerators chain before the LHC. It also feeds the North Area where a test hall for future equipment is located and where several experiments take data. (Image: Piotr Traczyk/CERN)


CERN Data Centre passes the 200-petabyte milestone

Thu, 07/06/2017 - 14:33

CERN’s Data Centre (Robert Hradil, Monika Majer/

Where do these data come from? Particles collide in the Large Hadron Collider (LHC) detectors approximately 1 billion times per second, generating about one petabyte of collision data per second. However, such quantities of data are impossible for current computing systems to record and they are hence filtered by the experiments, keeping only the most “interesting” ones. The filtered LHC data are then aggregated in the CERN Data Centre (DC), where initial data reconstruction is performed, and where a copy is archived to long-term tape storage. Even after the drastic data reduction performed by the experiments, the CERN DC processes on average one petabyte of data per day, and passed the milestone of 200 petabytes of data permanently archived in its tape libraries on 29 June 2017.

The four big LHC experiments have produced unprecedented volumes of data in the two last years. This is due in large part to the outstanding performance and availability of the LHC itself. Indeed, in 2016, expectations were initially for around 5 million seconds of data taking, while the final total was around 7.5 million seconds, a very welcome 50% increase. 2017 is following a similar trend.

Further, as luminosity is higher than in 2016, many collisions overlap and the events are more complex, requiring increasingly sophisticated reconstruction and analysis. This has a strong impact on computing requirements. Consequently, records are being broken in many aspects of data acquisition, data rates and data volumes, with exceptional levels of use for computing and storage resources. 

To face these challenges, the computing infrastructure at large, and notably the storage systems, went through major upgrades and consolidation during the two years of Long Shutdown 1. These upgrades enabled the data centre to cope with the 73 petabytes of data received in 2016 (49 of which were LHC data) and with the flow of data delivered so far in 2017. These upgrades also allowed the CERN Advanced STORage system (CASTOR) to pass the challenging milestone of 200 petabytes of permanently archived data. These permanently archived data represent an important fraction of the total amount of data received in the CERN data centre, the rest being temporary data which are periodically cleaned up.

Another consequence of the greater data volumes is an increased demand for data transfer  and thus a need for a higher network capacity. Since early February, a third 100Gb/s (gigabit per second) fibre optic circuit links the CERN DC to its remote extension hosted at the Wigner Research Centre for Physics (RCP) in Hungary, 1800km away. The additional bandwidth and redundancy provided by this third link help CERN benefit reliably from the computing power and storage at the remote extension. A must-have in the context of computing increasing needs! 

This map shows the routes for the three 100 Gbit/s fibre links between CERN and the Wigner RCP. The routes have been chosen carefully to ensure we maintain connectivity in the case of any incidents. (Image: Google)

LHCb announces a charming new particle

Thu, 07/06/2017 - 13:10

Image representing the new particle observed by LHCb, containing two charm quarks and one up quark. (Image: Daniel Dominguez/CERN)

Today at the EPS Conference on High Energy Physics in Venice, the LHCb experiment at CERN’s Large Hadron Collider has reported the observation of Ξcc++(Xicc++) a new particle containing two charm quarks and one up quark. The existence of this particle from the baryon family was expected by current theories, but physicists have been looking for such baryons with two heavy quarks for many years. The mass of the newly identified particle is about 3621 MeV, which is almost four times heavier than the most familiar baryon, the proton, a property that arises from its doubly charmed quark content. It is the first time that such a particle has been unambiguously detected.

Nearly all the matter that we see around us is made of baryons, which are common particles composed of three quarks, the best-known being protons and neutrons. But there are six types of existing quarks, and theoretically many different potential combinations could form other kinds of baryons. Baryons so far observed are all made of, at most, one heavy quark.

Finding a doubly heavy-quark baryon is of great interest as it will provide a unique tool to further probe quantum chromodynamics, the theory that describes the strong interaction, one of the four fundamental forces,” said Giovanni Passaleva, new Spokesperson of the LHCb collaboration. “Such particles will thus help us improve the predictive power of our theories.”

In contrast to other baryons, in which the three quarks perform an elaborate dance around each other, a doubly heavy baryon is expected to act like a planetary system, where the two heavy quarks play the role of heavy stars orbiting one around the other, with the lighter quark orbiting around this binary system,” added Guy Wilkinson, former Spokesperson of the collaboration.

Measuring the properties of the


Ξcc++ will help to establish how a system of two heavy quarks and a light quark behaves. Important insights can be obtained by precisely measuring production and decay mechanisms, and the lifetime of this new particle.

The observation of this new baryon proved to be challenging and has been made possible owing to the high production rate of heavy quarks at the LHC and to the unique capabilities of the LHCb experiment, which can identify the decay products with excellent efficiency. The Ξcc++ baryon was identified via its decay into a Λc+ baryon and three lighter mesons K-, π+ and π+.

The observation of the Ξcc++ in LHCb raises the expectations to detect other representatives of the family of doubly-heavy baryons. They will now be searched for at the LHC.

This result is based on 13 TeV data recorded during run 2 at the Large Hadron Collider, and confirmed using 8 TeV data from run 1. The collaboration has submitted a paper reporting these findings to the journal Physical Review Letters.

Find out more:  

Slovenia becomes CERN Associate Member State

Wed, 07/05/2017 - 10:24

Vojislav Šuc, Ambassador of the Republic of Slovenia to the United Nations Office and other international organisations in Geneva, gives the official letter of notification to Fabiola Gianotti, CERN Director general. (Image: Maximilien Brice/CERN)

On 4 July 2017, the Republic of Slovenia became an Associate Member in the pre-stage to Membership at CERN. This followed official notification to CERN that the Republic of Slovenia had completed its internal approval procedures as required for the entry into force of the Agreement, signed in December 2016, granting that status to the country.

Slovenia has a tradition of cooperation of several decades with CERN. Slovenian physicists contributed to the CERN programme long before Slovenia became an independent state in 1991, participating in an experiment at LEAR (the Low Energy Antiproton Ring) and on the DELPHI experiment – part of CERN’s previous large accelerator, the Large Electron Positron collider (LEP). In 1991, CERN and the Executive Council of the Assembly of the Republic of Slovenia concluded a Co-operation Agreement concerning the further development of scientific and technical co-operation in the research projects of CERN. In 2009, Slovenia applied to become a Member State of CERN.

For the past 20 years, Slovenian physicists have been participating in the ATLAS experiment at the Large Hadron Collider, from research and development, through construction and commissioning, to harvesting the physics results. Their focus has been on silicon tracking, protection devices and computing at the Slovenian TIER-2 data centre. They remain committed to the tracker upgrade, making use of the research reactor in Ljubljana for neutron irradiation studies.   

Slovenia is joining Cyprus and Serbia as an Associate Member State in the pre-stage to Membership of CERN. After a period of five years, Council will decide on the admission of Slovenia to full Membership.

Happy 5th anniversary, Higgs boson!

Tue, 07/04/2017 - 10:53

On 4 July 2012, the ATLAS and CMS spokespersons announced during a seminar at CERN that their experiments had found a particle consistent with the long sought-after Higgs boson. (Image: Maximilien Brice, Laurent Egli/CERN)

Where were you on 4 July 2012, the day in which the Higgs boson discovery was announced? Many people will be able to answer without referring to their diary. Perhaps you were among the few who had managed to secure a seat in CERN’s main auditorium, or who joined colleagues in universities and laboratories around the world at odd times of the day to watch the webcast.

“I think we have it, no?” was the question posed by the then CERN Director General Rolf Heuer on 4 July in the CERN auditorium. The answer was as obvious as the emotion on faces in the crowd. The then ATLAS and CMS spokespersons, Fabiola Gianotti and Joe Incandela, had just presented the latest Higgs search results based on roughly two years of LHC operations. Given the hints for the Higgs presented a few months earlier in December 2011, the frenzy of rumours on blogs and intense media interest during the preceding weeks, and a title for the CERN seminar that left little to the imagination, the outcome was anticipated. This did not temper excitement.

Video © CERN

The Higgs boson is the final and most interesting particle of the Standard Model (SM). The Higgs’ connections to many of the deepest current mysteries in physics mean the Higgs will remain a focus of activities for experimentalists and theorists for the foreseeable future.

Since then, we have learned much about the properties of this new particle, yet we are still at the beginning of our understanding. In the early days it was not even clear what the mass of the Higgs boson would be: the SM cannot predict it, it just needed to be measured. Indeed, in 1975, in the first published paper describing its possible experimental signatures, the allowed Higgs mass range at that time spanned four orders of magnitude, from 18 MeV to over 100 GeV.

By 4 July 2012 the picture was radically different. The Higgs no-show at previous colliders, including LEP at CERN and the Tevatron at Fermilab, had cornered its mass to be greater than 114 GeV, while theoretical limits required it to be below around 800 GeV. Once CERN’s LHC switched on, there was very little room left to hide for the Higgs boson: if the Higgs boson had a mass with a value in that energy range, the LHC would surely have been able to produced it. 

With the accelerator running it remained to observe the thing. This would push ingenuity to its limits. Physicists on the ATLAS and CMS detectors would need to work night and day to filter through the particle detritus from innumerable proton-proton collisions to select datasets of interest.  The search set tremendous challenges for the energy-resolution and particle-identification capabilities of the detectors, not to mention dealing with enormous volumes of data. In the end, the result of this labour reduced to a couple of plots. The discovery was clear for each collaboration: a significance pushing the five sigma “discovery” threshold.

Global media erupted in a science-fueled frenzy. It turns out that everyone gets excited when a fundamental building block of nature is discovered.

This article is a condensed excerpt from a feature article by Matthew Mccullough, published in the CERN Courier July/August 2017 issue, which you can read in full here.

Read the stories of how people experienced the event. You can share your story of 4 July 2012 on Twitter using the hashtag #HiggsStories.

The LHC racks up records

Fri, 06/30/2017 - 11:24

View of the LHC. It took only five weeks for the operators of the LHC to reach 2256 particle bunches circulating in each direction of the accelerator. (Image : Maximilien Brice/CERN)

An unprecedented number of particles has been reached in record time. Just five weeks after physics resumed, the Large Hadron Collider (LHC) is already running at full throttle. On Wednesday 28 June 2017 the LHC established yet another record-breaking high, with 2556 proton bunches circulating in each direction of the accelerator. The beams in the LHC are made up of bunches of protons, spaced seven metres (25 nanoseconds) apart, with each one containing more than 100 billion protons. 2556 is the maximum possible number of bunches that can be reached with the beam preparation method currently used.

The particle bunches that are delivered to the LHC are prepared and accelerated by a chain of four accelerators. Since last year, a new method to group and split the bunches enables the particles to be squeezed even closer together. With an equal number of protons, the beam diameter was reduced by 40 per cent. Denser bunches means a higher probability of collisions at the centre of the experiments.

This success has led to a new luminosity record for the LHC of 1.58x1034 cm-2s-1. This figure may not mean much to most of us, but it’s crucial for the accelerator’s experts. It measures the number of potential collisions per second and per unit of area . This new peak luminosity surpasses initial expectations defined by the original designs for the LHC, which  hoped it could reach a maximum of 1x1034cm-2s-1.

A higher luminosity means more collisions for the experiments collecting data: in just a few weeks ATLAS and CMS stored more than 6 inverse femtobarns, over an eighth of the total anticipated for the whole year.

Nevertheless, the operators cannot sit on their hands. Many parameters can be tuned to further improve the luminosity.

Next week, the LHC and its experiments will take a short break for the first of the two technical stops planned for the year. This will be an opportunity to carry out maintenance.

This plot shows the values of the luminosity reached during the last few weeks by the LHC, with the record of 1.58x1034 cm-2s-1 achieved on Wednesday 28 June.


Marie Curie, women and science, then and now

Thu, 06/29/2017 - 10:06

Hélène Langevin-Joliot at a conference organised by the "Graine de génie et Graine de citoyen" association in January 2014. (Image: Guillaume Perret/Graine de génie et Graine de citoyen)

Is there still a glass ceiling for women in science in 2017?

Physicist and granddaughter of Pierre and Marie Curie, Hélène Langevin-Joliot, will lecture at 8.30pm on 29 June at CERN in the Globe of Science and Innovation. Now the emeritus research director in fundamental nuclear physics at the CNRS in Orsay, France, she has witnessed first-hand the progress of women scientists throughout her long and very productive career.

The lecture, in French with simultaneous interpretation into English, will be webcast here.

From an eminent family of scientists (no less than four Nobel Prizes in chemistry and physics), and herself a researcher, she will talk about her career as a woman in a traditionally male-oriented profession.

“In France, the disparities between different disciplines became clear to me, as well as the effects of the glass ceiling,” she says. “Then the issue of gender equality took on a new significance, with new generations of women becoming more conscious of discrimination.”

Langevin-Joliot, daughter of Frédéric and Irène Joliot-Curie and granddaughter of Pierre and Marie Curie, grew up in an extraordinary and intellectually stimulating environment. “At school, I was only really passionate about solving maths problems. I found physics boring, too much about applying rules,” she recalls. “But my mother got hold of some experimental equipment for me and that was how I began to enjoy doing a bit of physics and chemistry.”

To say that the Curie women were feminists would be an understatement. Her mother and grandmother, both pioneers in their fields, supported her ambitions from a very early age and encouraged her to fight for important causes, such as helping women to access scientific careers and increasing scientific literacy among the general public.

Follow the webcast at 8.30pm on 29 June. 

Lithuania to become Associate Member of CERN

Tue, 06/27/2017 - 09:37

(Image: Official Office of the President of the Republic of Lithuania by Robertas Dačkus)

Today, in Vilnius, Lithuania, CERN Director General, Fabiola Gianotti, and the Minister of Foreign Affairs of the Republic of Lithuania, Linas Linkevičius, in the presence of the President of the Republic of Lithuania, Dalia Grybauskaitė, signed the Agreement admitting Lithuania as an Associate Member of CERN. The last step for the Agreement to enter into force requires final approval by the Government of Lithuania.

“Signing an agreement with CERN means recognition of Lithuanian science and talents as well as our common efforts in strengthening research, innovation and centres of excellence in the Baltic region,” said Dalia Grybauskaitė, President of the Republic of Lithuania.  “We are proud of this Associate Membership - cooperation with CERN gives a new impetus for economic growth, provides an opportunity for us to take part in global research and opens a wide horizon for our youth.”

 “The involvement of Lithuanian scientists at CERN has been growing steadily over the past decade, and Associate Membership can now serve as a catalyst to further strengthen particle physics and fundamental research in the country“, said Fabiola Gianotti. “We warmly welcome Lithuania into the CERN family, and look forward to enhancing our partnership in science, technology development and education and training.”

Lithuania’s relationship with CERN dates back to 2004, when an International Cooperation Agreement was signed between the Organization and the government of the Republic of Lithuania. This set priorities for the further development of scientific and technical cooperation between CERN and Lithuania in high-energy physics. One year later, in 2005, a Protocol to this Agreement was signed, paving the way for the participation of Lithuanian universities and scientific institutions in high-energy particle physics experiments at CERN.

Lithuania has contributed to the CMS experiment since 2007 when a Memorandum of Understanding (MoU) was signed marking the beginning of Lithuanian scientists’ involvement in the CMS collaboration. Lithuania has also played an important role in database development at CERN for CMS data mining and data quality analysis. Lithuania actively promoted the BalticGrid in 2005, allocating 100,000 CPU hours to CMS in 2007.

In addition to its involvement in the CMS experiment, Lithuania is part of two collaborations that aim to develop detector technologies to address the challenging upgrades needed for the High-Luminosity LHC.

Since 2004, CERN and Lithuania have also successfully collaborated on many educational activities aimed at strengthening the Lithuanian particle physics community. Lithuania has been participating in the CERN Summer Student programme and 53 Lithuanian teachers have taken part in CERN’s high-school teachers programme.

Associate Membership will allow Lithuania to take part in meetings of the CERN Council and its committees (Finance Committee and Scientific Policy Committee). It will also make Lithuanian nationals eligible for limited-duration staff appointments. Last but not least, Lithuanian industry will be entitled to bid for CERN contracts, opening up opportunities for industrial collaboration in areas of advanced technology.


The future of the LHC takes shape

Fri, 06/23/2017 - 16:23

View of a short-model magnet for the High Luminosity LHC quadrupole. (Image: Robert Hradil, Monika Majer/

While the Large Hadron Collider (LHC) is at the start of a new season of data taking, scientists and engineers around the world are already looking ahead, and working hard to develop its upgrade, the High-Luminosity LHC. This upgrade is planned to start operation in 2026, when it will increase the number of collisions by a factor of five to ten. Physicists will be able to take full advantage of this increased number of collisions to study the phenomena discovered at the LHC in greater detail.

This major upgrade to the machine requires installation of new equipment in 1.2 kilometres of the 27km-long-accelerator. Among the key components that will be installed are a set of new magnets: around 100 magnets of 11 new types are being developed.

More powerful superconducting quadrupole magnets will be installed at each side of the ATLAS and CMS detectors. Their purpose is to squeeze the particles closer, increasing the probability of collisions at the centre of the two experiments. These focusing magnets will exploit an innovative superconducting technology, based on the niobium-tin compound, which makes the quadrupoles’ magnetic field far greater, 50% higher than current LHC superconducting magnets based on niobium-titanium.

The magnets are now in the prototype phase – shorter models, on which tests are run to assess the stability of the design and the mechanical structure. Last year, two 1.5 metre-long short model quadrupoles were tested at CERN and at Fermilab, in the US. A third short model will soon be tested at CERN.

In January 2017, a full-length 4.5 metre-long coil – a world record-breaking length, for that kind of magnet – has been tested at the US Brookhaven National Laboratory and reached the nominal field value of 13.4 T. Meanwhile at CERN, winding the 7.15-metre-long coils for the final magnets has already begun.

The new magnets are being developed through a collaboration between CERN and the LHC-AUP (LHC Accelerator Upgrade Project) consortium, which involves three US laboratories.

This article is an excerpt from a feature article published here.

Watch the video!

(Video: Noemi Caraban Gonzalez/CERN)


Musician Howie Day records love song to physics

Fri, 06/23/2017 - 13:07

Singer Howie Day recorded a parody version of his song ‘Collide’ at CERN (Image: Noemi Caraban Gonzalez/CERN)

CERN’s American sibling Fermilab turns 50

Wed, 06/14/2017 - 14:39

This is an RF Cavity in the Recycler Ring in Fermilab’s Main Injector Tunnel, its most powerful particle accelerator (Image: Reidar Hahn/Fermilab)

Fifty years ago, physicists in the US established a new laboratory and with it a new approach to carrying out frontier research in high-energy physics. It began in the 1960's, when Cornell physicist Robert Rathbun Wilson saw early plans for a new accelerator in the US to rival Brookhaven National Laboratory in New York, and CERN in Switzerland, he considered them too conservative, unimaginative and too expensive. Wilson, being a modest yet proud man, thought he could design a better accelerator for less money and let his thoughts be known. By September 1965, he had proposed an alternative, innovative, less costly (approximately $90 million cheaper than the original) design. It was approved.

This period coincided with the Vietnam war, so the US Congress hoped to contain costs. Yet the discovery of the omega baryon particle at Brookhaven in 1964 meant high-energy physicists felt that a new high-energy accelerator was crucial to exploring new physics. Simultaneously, physicists were expressing frustration with the geographic situation of US high-energy physics facilities. 

Groundbreaking in October 1969 for the new 200 GeV Synchrotron (Image: Fermilab)

Against this backdrop arose a major movement to accommodate physicists in the centre of the country and offer more equal access. Columbia University experimental physicist Leon Lederman championed “the truly national laboratory” that would allow any qualifying proposal to be conducted at a national, rather than a regional, facility. In 1965, a consortium of major US research universities, Universities Research Association (URA), Inc., was established to manage and operate the accelerator laboratory for the AEC (and its successor agencies the Energy Research and Development Administration (ERDA) and the Department of Energy (DOE)) and address the need for a more national laboratory. 

Today, Wilson Hall, the central laboratory building, is the heart of the 6,800-acre Fermilab site. Following an architectural design competition among the DUSAF firms, it was built between 1971 and 1974. The design was acknowledged in 1975 with an award from the Society of American Registered Architects, and the building was named for Robert Rathbun Wilson on September 18, 1980. (Image: Reidar Hahn/ Fermilab)

Following a nationwide competition organised by the National Academy of Sciences, in December 1966 a 6800 acre site in Weston, Illinois, around 50 km west of Chicago, was selected. Another suburban Chicago site, north of Weston in affluent South Barrington, had withdrawn when local residents “feared that the influx of physicists would ‘disturb the moral fibre of their community’”. President Lyndon Johnson signed the bill authorising funding for the National Accelerator Laboratory on 21 November 1967.

Science dedicated to human rights

“The formation of the Laboratory shall be a positive force…toward open housing…[and] make a real contribution toward providing employment opportunities for minority groups”
Robert Wilson, Director of Fermilab

Fermilab’s Betz Prairie was once the largest prairie reconstruction project on the planet. The site now hosts about 1,000 acres of restored prairie and is also home to a herd of bison, a symbol of Fermilab’s place on the frontier of physics. (Image: Fermilab)

It wasn’t easy to recruit scientific staff to the new laboratory in open cornfields and farmland with few cultural amenities. That picture lies in stark contrast to today, with the lab encircled by suburban sprawl encouraged by highway construction and development of a high-tech corridor with neighbours including Bell Labs/AT&T and Amoco. Wilson encouraged people to join him in his challenge, promising higher energy and more experimental capability than originally planned. He and his wife, Jane, imbued the new laboratory with enthusiasm and hospitality, just as they had experienced in the isolated setting of wartime-era Los Alamos while Wilson carried out his work on the Manhattan Project.

Wilson and colleagues worked on the social conscience of the laboratory and in March 1968, a time of racial unrest in the US, they released a policy statement on human rights.

They intended to: “seek the achievement of its scientific goals within a framework of equal employment opportunity and of a deep dedication to the fundamental tenets of human rights and dignity…The formation of the Laboratory shall be a positive force…toward open housing…[and] make a real contribution toward providing employment opportunities for minority groups…Special opportunity must be provided to the educationally deprived…to exploit their inherent potential to contribute to and to benefit from the development of our Laboratory. Prejudice has no place in the pursuit of knowledge…It is essential that the Laboratory provide an environment in which both its staff and its visitors can live and work with pride and dignity. In any conflict between technical expediency and human rights we shall stand firmly on the side of human rights. This stand is taken because of, rather than in spite of, a dedication to science.” 

The campus brought inner-city youth out to the suburbs for employment, training them for many technical jobs. Congress supported this effort and was pleased to recognise it during the civil-rights movement of the late 1960s. Its affirmative spirit endures today.

Aerial view of Weston, the site for the National Accelerator laboratory in 1966 (Image: Fermilab)
Fermilab in 1977, showing the Main Ring accelerator (top) and Wilson Hall next to it. (Image: Fermilab)

International attraction

By the 1970's experimentalists from Europe and Asia flocked to propose research at the new frontier facility in the US, forging larger collaborations with American colleagues. Its forefront position and philosophy attracted the top physicists of the world, with Russian physicists making news working on the first approved experiment at Fermilab in the height of the Cold War. Congress was pleased and the scientists were overjoyed with more experimental areas than originally planned and with higher energy, as the magnets were improved to attain higher and higher energies within two years. The higher energy in a fixed-target accelerator complex allowed more innovative experiments, in particular enabling the discovery of the bottom quark in 1977.

Fermilab has had many successes over the past fifty years, including the discovery of the bottom quark in 1977. (Image: Fermilab)

Superconducting-magnet technology was the future for high-energy physics, and was championed by Wilson, and a new director to take this forward was sought. Lederman, champion of the "national laboratory", spokesperson of the Fermilab study that discovered the bottom quark, and later a Nobel Prize winner for the discovery of the muon, accepted the position in late 1978 and immediately set out to win support for Wilson’s energy doubler - a colliding-beams accelerator, which would employ superconductivity. Experts from Brookhaven and CERN, as well as the former USSR, shared ideas with Fermilab physicists to bring superconducting-magnet technology to fruition at Fermilab. This led to a trailblazing era during which Fermilab’s accelerator complex, now called the Tevatron, would lead the world in high-energy physics experiments.

By 1985 the Tevatron had achieved 800 GeV in fixed-target experiments and 1.6 TeV in colliding-beam experiments, and by the time of its closure in 2011 it had reached 1.96 TeV in the centre of mass – just shy of its original goal of 2 TeV.

A Remote Operations Center in Wilson Hall and a special US Observer agreement allowed Fermilab physicists to co-operate with CERN on LHC research and participate in the CMS experiment. (Image: Maximilien Brice/CERN)

Lederman also expanded the laboratory’s mission to include science education, offering programmes to local high-school students and teachers, and in 1980 opened the first children’s centre for employees of any DOE facility. Lederman also reached out to many regions including Latin America and partnered with businesses to support the lab’s research and encourage technology transfer. The latter included Wilson’s early Fermilab initiative of neutron therapy for certain cancers, which later would see Fermilab build the 70–250 MeV proton synchrotron for the Loma Linda Medical Center in California.

A time-lapse of the Fermilab muon g-2 ring being installed and prepped, from June 27, 2014 to June 5, 2015. Replay Animation (Image: Fermilab)

In 1999, experimentalist and former Fermilab user Michael Witherell of the University of California at Santa Barbara became Fermilab’s fourth director. Mirroring the spirt of US–European competition of the 1960s, this period saw CERN begin construction of the Large Hadron Collider (LHC) to search for the Higgs boson. Accordingly, the luminosity of the Tevatron became a priority, as did discussions about a possible future international linear collider. After launching the Neutrinos at the Main Injector (NuMI) research programme, including sending the underground particle beam off-site to the MINOS detector in Minnesota, Witherell returned to Santa Barbara in 2005. Physicist Piermaria Oddone from Lawrence Berkeley Laboratory became Fermilab’s fifth director in 2005. He pursued the renewal of the Tevatron in order to exploit the intensity frontier and explore new physics with a plan called “Project X”, part of the “Proton Improvement Plan”. A Remote Operations Center in Wilson Hall and a special US Observer agreement allowed Fermilab physicists to co-operate with CERN on LHC research and participate in the CMS experiment. The Higgs boson was duly discovered at CERN in 2012 and Oddone retired the following year.

Currently, prototypes for the future DUNE experiment are being built at CERN (Image: Maximilien Brice/CERN)

Under its sixth director, Nigel Lockyer, Fermilab now looks to shine once more through continued exploration of the intensity frontier and understanding the properties of neutrinos. In the next few years, Fermilab’s Long-Baseline Neutrino Facility (LBNF) will send neutrinos to the underground DUNE experiment 1300 km away in South Dakota, prototype detectors for which are currently being built at CERN. Meanwhile, Fermilab’s Short-Baseline Neutrino programme has just taken delivery of the 760 tonne cryostat for its ICARUS experiment after its recent refurbishment at CERN, while a major experiment called Muon g-2 is about to take its first results.

This suite of experiments, with co-operation with CERN and other international labs, puts Fermilab at the leading edge of the intensity frontier and continues Wilson’s dreams of exploration and discovery.


This article is a condensed excerpt from a feature article by Adrienne Kolb, published in The CERN Courier June 2017 issue, which you can read in full here.

High-school physicists win chance to run experiments at CERN

Tue, 06/13/2017 - 16:05

One of the teams who won Beamline for Schools 2016 perform their experiment using a CERN accelerator beam (Image: Noemi Caraban Gonzalez/CERN)

CERN today announced the winners of its 2017 Beamline for Schools competition. “Charging Cavaliers” from Canada and “TCO-ASA” from Italy were selected from a total of 180 teams from 43 countries around the world, adding up to about 1500 high-school students. The winners have been selected to come to CERN in September to carry out their own experiments using a CERN accelerator beam.

With the Beamline for Schools competition, high-school students are enabled to run an experiment on a fully-equipped CERN beamline, in the same way that researchers do at the Large Hadron Collider and other CERN facilities. Students had to submit a written proposal and video explaining why they wanted to come to CERN, what they hoped to take away from the experience and initial thoughts of how they would use the particle beam for their experiment. Taking into consideration creativity, motivation, feasibility and scientific method, CERN experts evaluated the proposals. A final selection was presented to the CERN scientific committee responsible for assigning beam time to experiments, who chose two winning teams to carry out their experiments together at CERN.

The quality and creativity of the proposals is inspiring. It shows the remarkable talent and commitment of the new generation of potential scientists and engineers. I congratulate all who have taken part this year; they can all be proud of their achievements. We very much look forward to welcoming the two winning teams and seeing the outcome of their experiments  CERN Director for International Relations, Charlotte Warakaulle

 “Charging Cavaliers” are thirteen students (6 boys and 7 girls) from the “École secondaire catholique Père-René-de-Galinée” in Cambridge, Canada. Their project is the search for elementary particles with a fractional charge, by observing their light emission in the same type of liquid scintillator as that used in the SNO+ experiment at SNOLAB. With this proposal, they are questioning the Standard Model of particle physics and trying to get a glimpse at a yet unexplored territory.

“I still can’t believe what happened. I feel incredibly privileged to be given this opportunity. It’s a once a lifetime opportunity It opens so many doors to a knowledge otherwise inaccessible to me. It represents the hard work our team has done. There’s just no words to describe it. Of course, I’m looking forward to putting our theory into practice in the hope of discovering fractionally charged particles, but most of all to expanding my knowledge of physics.” said Denisa Logojan from the Charging Cavaliers.

Watch the Charging Cavaliers's proposal video here (Video: Charging Cavaliers/Beamline for Schools/CERN)

“TCO-ASA” is a team from the “Liceo Scientifico Statale "T.C. Onesti"” in Fermo, Italy, and comprises 8 students (6 boys and 2 girls). They have taken the initiative to build a Cherenkov detector at their school. This detector has the potential of observing the effects of elementary particles moving faster than light does in the surrounding medium. Their plan is to test this detector, which is entirely made from low-cost and easily available materials, in the beam line at CERN.

“I'm really excited about our win, because I've never had an experience like this. Fermo is a small city and I've never had the opportunity to be in a physics laboratory with scientists that study every day to discover something new. I think that this experience will bring me a bit closer to my choices for my future” said Roberta Barbieri from TCO-ASA team.

The eight students from Italy sent their video proposal for their project, A blue light in the darkness (Video: TCo-ASA/Beamline for Schools/CERN)

The first Beamline for Schools competition was launched three years ago on the occasion of CERN’s 60th anniversary. To date, winners from the Netherlands, Greece, Italy, South Africa Poland and the United Kingdom have performed their experiments at CERN. This year, short-listed teams2 each receive a Cosmic-Pi detector for their school that will allow them to detect cosmic-ray particles coming from outer space.

 “After four editions, the Beamline for Schools competition has well established itself as an important outreach and education activity of CERN. This competition has the power to inspire thousands of young and curious minds to think about the role of science and technology in our society. Many of the proposals that we have received this year would have merited an invitation to CERN.”, said Markus Joos, Beamline for School project leader.


Beamline for Schools is an education and outreach project supported by the CERN & Society Foundation, funded by individuals, foundations and companies. The project was funded in 2017 in part by the Arconic Foundation; additional contributions were received by the Motorola Solutions Foundation, as well as from National Instruments. CERN would like to thank all the supporters for their generous contributions that have made the 2017 competition possible. 

Follow the fantastic voyage of the ICARUS detector

Mon, 06/12/2017 - 10:56

ICARUS has been at CERN for refurbishment before it makes its way to Fermilab over the next few months (Image: Maximilien Brice/CERN)

It’s lived in two different countries and is about to make its way to a third. It’s the largest machine of its kind, designed to find extremely elusive particles and tell us more about them. Its pioneering technology is the blueprint for some of the most advanced science experiments in the world. And this summer, it will travel across the Atlantic Ocean to its new home (and its new mission) at the U.S. Department of Energy’s Fermi National Accelerator Laboratory.

It’s called ICARUS, and you can follow its journey over land and sea with the help of an interactive map at, or on Facebook, Twitter and Instagram using the hashtag #IcarusTrip.

We'll be hosting a Facebook live today to tell you more about the ICARUS story, sign up to watch it live on Facebook.

The ICARUS detector measures 18 meters (60 feet) long and weighs 120 tons. It began its scientific life under a mountain at the Italian National Institute for Nuclear Physics’ (INFN) Gran Sasso National Laboratory in Italy in 2010, recording data from a beam of particles called neutrinos sent by CERN [LINK]. The detector was shipped to CERN in 2014, where it has been upgraded and refurbished in preparation for its overseas trek.

“We are very pleased and proud that CERN has been able to contribute to the refurbishment of the ICARUS detector and we are looking forward to first results from the Fermilab short-baseline neutrino programme in the coming years,” said Fabiola Gianotti, Director-General of CERN.

When it arrives at Fermilab, the massive machine will take its place as part of a suite of three detectors dedicated to searching for a new type of neutrino beyond the three that have been found. Discovering this so-called “sterile” neutrino, should it exist, would rewrite scientists’ picture of the universe and the particles that make it up.

“Nailing down the question of whether sterile neutrinos exist or not is an important scientific goal, and ICARUS will help us achieve that,” said Fermilab Director Nigel Lockyer. “But it’s also a significant step in Fermilab’s plan to host a truly international neutrino facility, with the help of our partners around the world.”  

First, however, the detector has to get there. Next week it will begin its journey from CERN in Geneva, Switzerland to a port in Antwerp, Belgium. From there the detector, separated into two identical pieces, will travel on a ship to Burns Harbor, Indiana, in the United States, and from there will be driven by truck to Fermilab, one piece at a time. The full trip is expected to take roughly six weeks.

The detector uses liquid-argon time projection technology – essentially a method of taking a 3-D snapshot of the particles produced when a neutrino interacts with an argon atom – which was developed by the ICARUS collaboration, and now is the technology of choice for the international Deep Underground Neutrino Experiment (DUNE), prototypes of which are currently being built at CERN.

"More than 25 years ago Nobel Prize winner, and a previous CERN Director-General, Carlo Rubbia started a visionary effort with the help and resources of INFN to make use of liquid argon as a particle detector, with the visual power of a bubble chamber but with the speed and efficiency of an electronic detector,” said Fernando Ferroni, president of INFN. “A long series of steps demonstrated the power of this technology that has been chosen for the gigantic future experiment DUNE in the U.S., scaling up the 760 tons of argon for ICARUS to 70,000 tons for DUNE. In the meantime, ICARUS will be at the core of an experiment at Fermilab looking for the possible existence of a new type of neutrino. Long life to ICARUS!”

This research is supported by the DOE Office of Science, CERN and INFN, in partnership with institutions around the world. 

Discover the hidden treasures of CERN’s archive

Fri, 06/09/2017 - 11:13

International Archives Day, 9 June, is an opportunity to discover treasures from our shared heritage. The CERN archives contain some 1000 metres of shelves filled with letters, notes and reports. CERN also preserves a large number of films, photos, videos and objects. These precious nuggets contain 63 years of CERN’s history and are a chapter in the unique story that is scientific adventure.

CERN also owns the scientific archive of 1945 Nobel prize-winning physicist, Wolfgang Pauli. This small, but historically valuable, collection was donated by Pauli’s widow who, with the help of friends, tracked down originals or copies of his letters. His correspondence, with Bohr, Heisenberg, Einstein and others, provides an invaluable resource and insight into the development of 20th century science.

Read more about CERN archives here.