Launched in 2014, the Beamline for Schools (BL4S) competition allows high-school students between 16 and 18 years old to run a real experiment at CERN’s PS accelerator. For two years, students and schools worldwide have risen to the challenge and taken part enthusiastically in the competition. To ensure that it runs smoothly and enjoyably, over 100 CERN people work behind the scenes. The Bulletin lifts the curtain: read the full article here.

THE Port hackathon took place at CERN and Geneva’s Campus Biotech from 2 to 4 October. Among the various prototypes presented at the final event was a novel solution for the special mask that children suffering from xeroderma pigmentosum have to wear to reduce their risk of getting skin cancer.

The Bulletin reports on full here.

CERN will be back at the Montreux Jazz Festival for its third annual workshop: ‘The Physics of Music and The Music of Physics’ on 9 July at 3 pm in Petit Palais.

Run 2 of the LHC began this spring, bringing with it hopes and promise of new physics and discovery. One of many key items on the LHC shopping list is the existence of new spatial dimensions, a potential means to harmonise gravity in our theoretical understanding of nature.

Robert Kieffer of the CERN Beam Instrumentation Group and Gaëtan Parseihian of the Laboratoire de Mécanique et d'Acoustique, CNRS, Marseille, will animate the Physics of Music half of the workshop with a demonstration of the physics behind acoustics. Their programme includes a lesson on sound sculpture and the addition of spatial dimensions to music, followed by a discussion and demonstration of sound perception. Participants will then be treated to an ambisonic concert composed from various sounds made at CERN.

The Music of Physics half of the workshop will be animated by Juliana Cherston of the Massachusetts Institute of Technology Media Lab in the US, Domenico Vicinanza of Anglia Ruskin University in the UK and the GEANT Association, and Ewan Hill of the University of Victoria in Canada, TRIUMF, and the ATLAS Experiment at CERN. They will present a new project that maps physical parameters of LHC proton collisions to sound parameters, thus creating music from the particle events. 

The grand finale will feature jazz pianist Al Blatter playing a duet with sonified live collisions from the LHC. In his attempt to bring harmony between humankind and nature, Al hopes to bring music to a higher dimension – a feat only possible at the Montreux Jazz Festival.

Find out more here  

The CERN Grey Book database has a brand new look.

The database stores data on the Organization’s research programme, including all the experiments and projects, their collaborating institutes and their participants.

Now, 15 years after its last web interface was released, the Grey Book has a new look. There have been changes to search and navigation, as well as structural changes to the database - now data is directly accessed from the CERN’s Foundation database.

“I am really happy with the way you can navigate dynamically and in multiple ways between the views of the different domain items,” says Doris Chromek-Burckhart, who heads the Users’ Office, which maintains the database.

“The new site offers global as well as context-specific search options that make it really easy, for example, to find all the scientific collaborators of an experiment in just one click. In addition, when signed in, all those lists can be exported to excel or as pdf files. It is powerful and elegant!”

CERN has published annually a full list of the experiments and projects that take place at the laboratory since 1975. Until 2000, when the database went online, these lists were printed and bound with a grey cover, hence the name.

Visit the new site at the usual URL: greybook.cern.ch

At the start of the summer, the teams developing the magnets for the future HL-LHC were in high spirits. On 16 June, a 11-Tesla superconducting dipole magnet model manufactured at CERN reached record performance levels, surpassing those of its predecessors. The model was tested in a special cryostat in hall SM18 and its magnetic field intensity exceeded 11 Tesla after just six quenches: a much faster increase in intensity than previous models. In addition, it reached a magnetic field intensity of 12 Tesla (corresponding to a current of 12,800 amps in the coil); higher than any of the previous models. “This is excellent news for the HL-LHC project,” says Frédéric Savary of the Technology department, who is in charge of the tests. “These results demonstrate CERN’s extensive know-how in the manufacture of high-field superconducting magnets.”

The HL-LHC project is an integral part of the Laboratory’s Medium-Term Plan and aims to increase the number of collisions in the LHC by a factor of 5 to 10 in order to reach an integrated luminosity of 250 fb^-1 per year as of 2025. To achieve this goal, 1.2 km of the current accelerator will be replaced with new machinery. One of the changes required to allow operation at this luminosity is an increase in the number of collimators, devices that protect the machine from particles that stray from the beam. But installing more collimators in the ring results in less space for magnets, so the current dipole magnets will be replaced by pairs of shorter but more powerful magnets. In the HL-LHC, two new 5.5-metre-long dipole magnets (i.e. 11 metres in total) will have to bend the beam just as effectively as the present 15-metre-long magnets. As a result, these magnets will have to generate an 11-Tesla magnetic field, compared to the 8 Tesla field generated by the current magnets.

The conductor for the new superconducting dipole magnets is made from an intermetallic compound of niobium and tin (Nb₃Sn). The magnets are being developed in the framework of a collaboration between the US laboratory Fermilab and CERN. Single-bore models have already been constructed on both sides of the Atlantic, four in total. They too have reached the required 11 Tesla, but only after many quenches, so the performance of the new model was enthusiastically welcomed by the teams that have been working on the project for almost five years.

Nevertheless, the development work is far from over. The models are shorter than the final magnets will be: 2 metres in length rather than 5.5 metres. They also only have one bore, i.e. they are single dipoles producing a field that can guide only one beam. The final magnet will consist of two dipoles, i.e. two bores for the two beam pipes, in the same cryostat, just like the current LHC magnets.

The heatwave affecting many parts of Europe has been often in the news this summer, but we’ve also had plenty of “hot news” at CERN, in particular regarding the LHC and the experiments.

There’s been great excitement everywhere about the restart of the LHC. However, we should not forget just how much work was done during the long shutdown, and that in many ways it’s like starting up a new machine, with all the surprises that can bring. This year, the LHC has already run at the record-breaking collision energy of 13 TeV and now we’re seeing the careful, step-by-step procedure to increase the beam intensity. The aim, as it always was, is to have the collider up to its full performance by the end of the year, so that we can then embark on three years full of physics.

Nevertheless, the LHC experiments already have 100 times more data than they did at around the same time after the machine first started up at a collision energy of 7 TeV in 2010. This has allowed the experiments to renew their acquaintance with many “old friends” among the fundamental particles and processes of the Standard Model. It’s also already provided sufficient data for the first publication to come out of Run 2.

This was big news at the first of the year’s major international particle-physics conferences, the 2015 European Physical Society Conference on High Energy Physics(EPS-HEP2015), which took place recently in Vienna. Status reports on the LHC, ATLAS and CMS all figured in the main plenary sessions – and were very positively received. They included the first results at 13 TeV, with spectacular events that show the power of the energy increase. It’s clear from the conference that all eyes are on Run 2; not only particle physicists, but the physics community at large is eagerly awaiting the more significant amount of data that is to come. In the meantime, the final harvest from Run 1 continues, and can still provide exciting results, as LHCb’s discovery of a new class of particles, the pentaquarks, has amply demonstrated.

The conference also revealed a clear trend towards further exploiting the synergies between particle physics and cosmology. The two disciplines investigate two fundamental scalar fields, which appear similar and may even be connected. These are the field associated with the Brout–Englert–Higgs mechanism in particle physics, and one that is linked to a period of extremely rapid expansion, or “inflation”, in the very early Universe. 

Back at CERN, the latest news concerns more than the LHC. I am pleased to announce that as from today Pakistan is an Associate Member State of CERN. Official notification that Pakistan has ratified the Association Agreement arrived through diplomatic channels this morning. I am certain that you will join me in welcoming Pakistan as an Associate Member State.

As the LHC Physics conference gets underway in St Petersburg, it’s a good time to take stock of where things stand with run-2.  For all those involved with operating the LHC and its experiments in this new energy and intensity regime, 2015 was always going to be a learning curve. And learning we most certainly are. The main objective for this year has always been to set up the machine and experiments for production running at high energy and high intensity in 2016, 17 and 18.  That said, the experiments have all been able to collect quality data at 13 TeV, with the first run-2 papers and conference presentations being written and delivered this summer.

It would be unfair of me, however, to give the impression that it’s all been plain sailing. As well as the highs: smooth recommissioning of the machine, physics getting underway, and a successful transition to 25-nanosecond bunch spacing, we’ve also had our fair share of lows. There have been no show-stoppers, but rather a series of more minor issues that have slowed things down. Sensitivity of the quench-protection system, now fully understood and due to be rectified in the September technical stop, has cost us time. Synchrotron radiation and electron clouds become more of an issue at the energy we’re now running at, so we have to learn how to live with that. And the infamous Unidentified Falling Objects – UFOs – are back, though there is now strong evidence that these decrease with time. All in all, as time goes on, the LHC’s performance gets better, and I believe it is shaping up well to deliver good beam for the rest of 2015 and through the production phase of run-2 starting in 2016.

For the experiments, most things have gone smoothly, but many of you will be aware that the cryogenic system supplying the CMS magnet has been having some difficulty. As a result, a fraction of the data CMS has taken this year is at zero-field. As I write, the system seems to be stable, but it’s clear that there are contaminants in the cold box that supplies the magnet with liquid helium, and this will therefore need a thorough clean. Interim measures are being taken during the technical stop, aimed at finding a way to continue to operate the magnet with an acceptable duty cycle. All being well, CMS will be able to take data satisfactorily with field on until the end of the 2015 physics programme, postponing the cleaning operation until the winter stop in order to be ready for the start of 2016.

To conclude, I’d like to congratulate everyone concerned in getting us to where we are today: on the threshold of the first LHC Physics conference with 13 TeV data on display. Along with the continuing flow of exciting results from run-1, such as the combined ATLAS-CMS result on Higgs couplings presented today, there’s much good physics to digest already from run-2. And as we approach the top of the learning curve, there’s the promise of very much more to come.

This summer, the HiRadMat (High Radiation to Materials) facility began testing the first HL-LHC collimator jaw prototypes. How they perform when bombarded with high-energy, high-intensity beams will go on to shape the particle accelerators of the future.

The HiRadMat facility uses SPS beams to test materials and accelerator components in extreme conditions. As accelerators grow more powerful, they require materials that can withstand extreme conditions of temperature and pressure as well as high levels of radiation.

In 2012, in a HiRadMat experiment, six different materials were probed for possible use in collimators and absorbers. The results (see box) saw two standout performances from molybdenum-graphite and copper-diamond. These contenders have moved forward to the next round and three full collimator jaws (one typical LHC jaw and two made with the new materials for the future HL-LHC) are being put to the test in a dedicated experiment – led by CERN’s Mechanical and Materials Engineering (EN/MME) group, with support from several groups from the EN, BE, TE and PH departments. “These novel materials have undergone several years of development and optimisation,” says Alessandro Bertarelli, team leader of the “Jaws” experiment. “They are now ready for harsh tests in their final configuration, that of a full-scale collimator jaw for the HL-LHC.”

“We are doing detailed studies in different ‘accident’ situations, and seeing how the three jaws perform,” adds Michael Guinchard, who is in charge of the experiment’s complex instrumentation and data acquisition system. “We have recreated a beam injection error situation – that’s when bunches directly impact the jaw – and, so far, have found the results agree with our simulations. By the end of the year, we hope to validate which of the jaws will be mounted in a HL-LHC collimator prototype for final qualification.”

In addition to the electrical strain gauges, temperature gauges, laser doppler vibrometer and a high speed camera that adorned the 2012 experiment, the experiment team has added a whole new host of instrumentation for 2015. “Most notably, we are using optical fibres to study the jaw while it is being hit by beams,” says Guinchard. The optical fibres are bonded directly to the surface of the jaws and, when impacted by beam, they deform. This leads to subtle changes in their signal, providing a highly sensitive picture of the jaw’s deformation, ideally complementing information from the electrical strain-gauges.

The team has also installed new ultrasound devices to map the inside of the materials. These small probes are just 8 mm in diameter and can work in high-temperature (350°C), high-radiation (1000 kGy) environments. “Ultrasounds will help us look beyond superficial damage and straight into the heart of the material,” says Federico Carra, who is in charge of HL-LHC collimator mechanical design and engineering. “Now we can detect the propagation of cracks, internal melting and other non-visible defects.”

Molybdenum-graphite has also garnered attention from outside CERN. “In addition to being shock resistant, it is very light and extremely conductive, and so could be ideal for a broad range of applications,” says Carra.  “For example, it could be used in high-end electronics, avionics or even advanced braking systems. We are working with CERN’s Knowledge Transfer group to explore further applications.”

AWAKE is the proof-of-principle experiment whose aim is to use protons to generate powerful wakefields to accelerate an electron beam. With accelerator gradients hundreds of times higher than those used in current systems, this technique could revolutionise the field of particle acceleration. Installed in the tunnel previously used by the CNGS facility, AWAKE is completing the service installation phase and will receive the plasma cell in the coming months.

AWAKE is the world’s first proton-driven plasma wakefield acceleration experiment. In AWAKE, a beam of protons from the SPS will be travelling through a plasma cell and this will generate a wakefield that, in turn, will accelerate an electron beam. A laser will ionise the gas in the plasma cell and seed the self-modulation instability that will trigger the wakefield in the plasma.

The project aims to prove that the plasma wakefield can be driven with protons and that acceleration will be extremely powerful, hundreds of times more powerful than that achieved today.

Over about 18 months of hard work, the teams have cleared the old CNGS area – leaving only the infrastructure that will be reused by AWAKE – and have modified the services to meet AWAKE’s needs. “We dismantled 100 metres of the proton beam line, completed the civil-engineering needed to house the new electron and laser beam lines, removed several kilometres of old cables, and installed some 100 kilometres of new cables,” says Edda Gschwendtner, CERN AWAKE project leader. “We have installed the 16 magnets for the proton line for AWAKE, built the laser clean room, modified the access and cooling and ventilation… It has been a huge amount of work in a very short time.”

Integrating a new experiment into an existing facility is extremely challenging, but now that the area has been cleared and is ready for the future installations, Ans Pardons, AWAKE’s Coordination Package Leader for Integration and Installation, speaks with a smile: “It has been a challenging time for the CERN teams and the collaborating institutes involved in the project, but we can’t relax yet! We are now looking forward to installing the various beam and diagnostics components and starting to test them.”

One of AWAKE’s core components is the 10-metre-long plasma cell that will be arriving in the tunnel in a couple of months. A first prototype has successfully completed commissioning tests in CERN's North Area where the uniformity of the plasma temperature in the cell has been validated. The installation of the plasma cell in the AWAKE tunnel will be followed by the installation of the laser, the vacuum equipment and the diagnostic system for both laser and proton beams. In March 2016, the proton line, the laser and the experimental equipment will be ready for hardware commissioning, and beam commissioning will start in the summer. “Next year will continue to be very intense for the whole collaboration,” confirms Edda. “Indeed, in parallel to starting physics using the proton beam line, we will continue the installation of the electron line with the aim of starting the acceleration tests in 2017.”

If everything goes as planned, the AWAKE collaboration hopes to measure the first wakefields in the plasma cell in about one year from now

The NA62 Gigatracker is a jewel of technology: its sensor, which delivers the time of the crossing particles with a precision of less than 200 picoseconds (better than similar LHC detectors), has a cooling system that might become the precursor to a completely new detector technique.

The NA62 Gigatracker (GTK) is composed of a set of three innovative silicon pixel detectors, whose job is to measure the arrival time and the position of the incoming beam particles. Installed in the heart of the NA62 detector, the silicon sensors are cooled down (to about -20 degrees Celsius) by a microfluidic silicon device. “The cooling system is needed to remove the heat produced by the readout chips the silicon sensor is bonded to,” explains Alessandro Mapelli, microsystems engineer working in the Physics department. “For the NA62 Gigatracker we have designed a cooling plate on top of which both the silicon sensor and the readout chip are bonded.”

One hundred and fifty microchannels are etched in the ultrathin silicon cooling plate in which a coolant circulates and keeps the whole system at its operating temperature. Each of the microchannels is just 70 µm deep and the silicon plate is only a few dozen µm thicker. This means that the microchannel cooling system can be implemented in silicon trackers as the additional material the beam particles have to cross is minimised and therefore the influence on the particle track is reduced significantly compared to traditional cooling methods. The stable low temperature helps to reduce the radiation damage to the detector and therefore increases its lifetime in the harsh environment.

In the NA62 GTK, the sensors, readout electronics and cooling plates are all made of silicon. This is why the natural evolution scientists are thinking of is the integration of all the three components in one single device. “This is what we call a 'monolithic device',” explains Mapelli. “In particle physics experiments, it is very important to reduce the amount of material used in high-precision detectors. A single device incorporating the sensing layer, the electronics, and the services, such as the cooling, would be a very compact and thin system. It would also be less fragile than the current systems because it would require fewer manipulations. Finally, it would be more effective as the distance between the point where the heat is produced – namely the readout chip – and the coolant would be minimised.”

Experts in the CERN Physics department are currently working on future developments of this technology for high-energy physics detectors and beyond, as this technique could also be used in high-density computing, medical imaging and, more generally, in fields where images with sub-nanosecond time-measurement precision are used.

Launched in 2014, the Beamline for Schools (BL4S) competition allows high-school students between 16 and 18 years old to run a real experiment at CERN’s PS accelerator. For two years, students and schools worldwide have risen to the challenge and taken part enthusiastically in the competition. To ensure that it runs smoothly and enjoyably, over 100 CERN people work behind the scenes. The Bulletin lifts the curtain: read the full article here.

THE Port hackathon took place at CERN and Geneva’s Campus Biotech from 2 to 4 October. Among the various prototypes presented at the final event was a novel solution for the special mask that children suffering from xeroderma pigmentosum have to wear to reduce their risk of getting skin cancer.

The Bulletin reports on full here.

The Linac4 accelerator is now prepared to reach 50 MeV. This milestone energy - expected in the coming weeks - will allow the machine to act as a replacement for the ageing Linac2, four years before it takes over at the head of the accelerator chain in 2020. Read the full article in the Bulletin here. 

A new LHCb programme is delving into uncharted waters for the LHC: exploring how protons interact with noble gases inside the machine pipe. While, at first glance, it may sound risky for the overall quality of the vacuum in the machine, the procedure is safe and potentially very rich in rewards. The results could uncover the high-energy helium-proton cross-section (with all the implications thereof), explore new boundaries of the quark-gluon plasma and much more. Read the full article in The Bulletin here. 

Bent crystals can be used to deflect particle beams, as suggested by E. Tsyganov in 1976. Experimental demonstrations have been carried out for four decades in various laboratories worldwide. In recent tests, a bent crystal inserted into the LHC beam halo successfully channelled and deflected 6.5 TeV protons into an absorber, with reduced secondary irradiation. Read the Bulletin article.

In preparation for the civil engineering work on the HL-LHC, vibration measurements were carried out at the LHC’s Point 1 last month. These measurements will help evaluate how civil engineering work could impact the beam, and will provide crucial details about the site’s geological make-up before construction begins. Read more in the Bulletin.

Dear Colleagues,

As we embark on a new year at CERN, I’d like to welcome you all back and wish you the very best for 2016. I hope you all had a relaxing end of year break and are looking forward, as I am, to an exciting year in the life of CERN.

As the new management team begins its five-year mandate to lead this great Organization, we inherit a Laboratory in excellent shape. For that I’d like to thank Rolf Heuer and his team, along with all of you, for keeping CERN in such good health.

CERN is, first and foremost, a laboratory for fundamental research in physics. It is also a place where science stimulates technological innovation. It’s a place that inspires future generations, either to pursue scientific careers, or simply to develop into citizens aware of the value of science in today’s society. And it’s a place where scientists from all over the world come together to share the pursuit of knowledge. That is an incredibly noble ideal, making CERN a paragon of tolerance and mutual respect.

Over the next five years, we have challenges to face. We need to ensure excellent performance of the LHC accelerator, detectors and computing, in order to deliver exciting science at the energy frontier. We need to maintain a diverse and compelling scientific programme. And we need to start building the long-term future of our field. CERN’s rich experimental programme, which makes our Laboratory unique, promises significant advances in the understanding of fundamental physics, and I am much looking forward to seeing what nature has to reveal. 

As well as in research, there will be challenges elsewhere as we move forward. There are new emerging players to be integrated into the world’s particle physics research landscape, for example, and budgets for research are tight in countries around the world. 

To bring this message to a close, I’d like to reiterate my invitation for you to join me in the CERN Main Auditorium, or by webcast, on Monday 18 January at 10:00 where you’ll have the opportunity to meet the new Directorate.  We will present the new structure for CERN, along with our goals and challenges for the years to come. I look forward to seeing many of you there, and to working with you all over the coming years.

With my best wishes for 2016 to you and your families,

Fabiola Gianotti

More information about the new structure and the Directors.

In one of her first official duties as CERN Director General, Fabiola Gianotti met representatives of CERN’s local communities and international Geneva in Microcosm on Thursday evening to wish them a Happy New Year 2016, and to express thanks for their support. This ceremony continues a long-standing tradition, reflecting CERN’s important position in the Geneva region. The event also offers an opportunity for local representatives from both sides of the border to meet members of Geneva’s international community, and it is an occasion for CERN to nourish the relationship it enjoys with its host region.

This year, the first of a new mandate, a series of round tables will be organised with the aim of better understanding CERN’s relationship with its host region, and identifying tangible actions to further cement that relationship. This process takes forward an on-going engagement through which CERN has developed scientific tourism in the region, and engaged with school children at the primary level before they make the first choices that determine their future careers.

With over 100,000 public visitors a year, CERN is a key actor in scientific tourism. We have further developed a series of information platforms around the LHC with the title Passport to the Big Bang. In terms of primary education, a programme developed in partnership with the French Education Ministry, Geneva’s Education Department and Geneva University has turned hundreds of local children into budding scientists and been deployed as far afield as Latin America. CERN now looks forward to strengthening this interaction with the neighbouring region, and with visitors from across the world to shape the scientists and citizens of tomorrow.

The new year begins with some important changes for members of CERN personnel. The measures proposed by the Management following the five-yearly review of employment conditions, which were approved by the Council in December 2015, will be implemented gradually. What changes can we expect? Read more in the Bulletin.

As head of a major intergovernmental organisation, CERN’s Director General has a standing invitation to attend the World Economic Forum’s annual meeting of leaders in politics, business and other walks of life at the Swiss mountain resort of Davos, and it’s an invitation that Fabiola Gianotti accepted this year. The theme for this year’s meeting was ‘mastering the fourth industrial revolution’, expected to be characterised by the rise of new technologies such as robotics and 3D printing. As with any industrial revolution, pundits are predicting this one will be disruptive before bringing wide scale benefits to humanity as a whole.

During one packed day in Davos, Fabiola  had meetings with key players in the scientific establishment, media, business and political worlds, and she took part in a number of discussions on themes of diversity, sustainable development and open innovation. Throughout, her message was one of openness and inclusion. “Diversity,” she said, “means giving the same opportunities to everybody.” On the questions of sustainability and openness, she stressed CERN’s enduring commitment to an open model of research, and the enduring success of the CERN model for long-range international collaboration.