On 12 October, the ICARUS cryostat was extracted from Building 156 and brought to the front of Building 185, where the ICARUS detector is. Next, the detector will be inserted into it, and at the end of the year, shipped to Fermilab.
The aluminum cryostat, which will contain one of the two ICARUS twin detector modules, was assembled and welded together in Building 156 over the past few months. (Image: Didier Steyaert/CERN)On 12 October, the cry ostat was carefully extracted from the workshop of Building 156. It was loaded onto a big lorry......and extremely carefully manoeuvred through the streets of CERN’s Meryn site... ...to the front of Building 185. (Images: M. Brice/CERN)
Here, the first ICARUS detector module has been undergoing a complete refurbishment, lasting almost 20 months.
Next, the detector will be inserted into its own cryostat and, at the end of the year, shipped to Chicago to start its new adventure as a part of the Short Baseline Neutrino (SBN) programme at Fermilab.
The CERN Computer Security Team and our colleagues, as well as external students participating in the CERN WhiteHat Challenge and friendly peers around the world, repeatedly detect weaknesses and vulnerabilities in websites and software applications developed or run at CERN. It is a never-ending race between the good side and the evil-doers who would love to misuse those weaknesses and vulnerabilities to break into CERN and misuse our computing resources for their malicious deeds…
So why is software buggy? Of course, complexity is one argument why there will always be software flaws. But we shouldn’t hide behind that argument. The flaws are introduced by humans. Time pressure, suboptimal programming skills and lack of good practices mean that secure coding is overlooked. And there is no incentive to change that. Besides software, there are barely any other products worldwide where the customer has to bear all the consequences of a bad product: maybe drugs? In other fields that introduce risk for the user, such as engineering and medicine, the professionals creating products are required to be accredited and perform audits and safety checks. Perhaps we need to introduce a government-sponsored liability programme for any software being sold or distributed widely? Legally require software companies and programmers to have a bounty programme and make them pay for any vulnerability found in their software. The sum paid to the first finder might follow a nationwide (or even international?) catalogue. Cross-site scripting: 1000 CHF, SQL injection: 5000 CHF, remote code execution: 10,000 CHF. This payment might even be proportional to the user base of the vulnerable software. For Microsoft software, the payment is higher, for my software which barely anyone uses, the sum is lower. But they would only need to pay if their software is closed source. The bounty costs for open-source code would be covered by the government…
What would be the benefits? First of all, software companies and programmers would be required to pay attention to secure coding. Of course, they can decide that it is more effective for them to pay the bounty instead and get their software improved through external means. Or, even more beneficial to the world, make their software open source and have the government pay. Secondly, there would be an alternative to the black underground market for vulnerabilities and exploits. At least those GreyHats who make their living by selling vulnerabilities could be brought back into legality. For any other IT folks, e.g. computer science students, even you and I, who for ethical reasons never went Grey or BlackHat, can train themselves and earn additional revenue. And third, this programme would direct many more eyes on each software package. And the more eyes, the more vulnerabilities found and the more secure our software foundations. But we are far away from that. And there might be plenty of other details which would need to be considered, too…
For the moment, we have to count on YOU(!) to make any software that you deploy or develop more secure. At CERN, there are several options for programmers and software developers:
Katsuo Tokushuku (Collaboration Board Chairperson), Karolos Potamianos, Dave Charlton (ATLAS Spokesperson), Kerstin Lantzsch, Yosuke Takubo, Stephen Haywood (Chairperson of the selection committee) and Marcello Bindi. (Image: S. Biondi/ATLAS Experiment)
The 2016 ATLAS Outstanding Achievement Awards ceremony was held at CERN on 20 October. Now in its third year, the awards give recognition to excellent contributions made to the collaboration, with an emphasis on activities carried out in the first year of Run 2.
“There are a lot of excellent, hard-working people in ATLAS, as displayed by the quality and quantity of the nominations we received,” said Stephen Haywood, Chairperson of the selection committee. “As such, the committee had to make many hard choices, as we tried to pick out the ‘outstanding’ from all the excellent work nominated.”
As in previous years, nominations came from across the collaboration, in areas such as technical coordination, detector systems, as well as activity areas including upgrade, combined performance and outreach. The Collaboration Board Chair Advisory Group examined each of the 62 nominations to make their final selections.
The first to receive their awards were Marcello Bindi (University of Göttingen), Laura Jeanty (Berkeley National Lab), Kerstin Lantzsch (University of Bonn), Karolos Potamianos (Berkeley National Lab) and Yosuke Takubo (KEK). They were celebrated for their outstanding contributions to the successful commissioning and operation of the Pixel Detector for the start-up of Run 2.
On Tuesday, 11 October 2016, the American Physical Society (APS) announced the award of the 2017 W.K.H. Panofsky Prize in Experimental Particle Physics to Michel Della Negra (Imperial College London and, previously, CERN), Peter Jenni (Albert-Ludwigs-University Freiburg and, previously, CERN), and Tejinder Virdee (Imperial College London) “for distinguished leadership in the conception, design, and construction of the ATLAS and CMS detectors, which were instrumental in the discovery of the Higgs boson.”
On the same occasion, the 2017 J. J. Sakurai Prize for Theoretical Particle Physics was awarded to Sally Dawson (Brookhaven National Laboratory), John F. Gunion (University of California, Davis), Howard E. Haber (University of California, Santa Cruz), and Gordon L. Kane (University of Michigan) “for instrumental contributions to the theory of the properties, reactions, and signatures of the Higgs boson.”
“Each year, the American Physical Society recognises leading physicists through a variety of prizes and awards,” said APS President Dr Homer Neal. "We are proud to honour a spectrum of recipients, including outstanding early-career researchers, exceptional communicators and educators, and accomplished theorists and experimentalists working in every major field of physics.”
“CERN is very proud that the prestigious Panofsky Prize has been awarded to three of the early leaders of the ATLAS and CMS experiments. We also greatly appreciate the recognition of the important theoretical work on the Higgs boson phenomenology by four distinguished theoretical physicists. We are grateful to the APS for highlighting excellent scientific work related directly or indirectly to the LHC project, to which our US colleagues have contributed in a very significant way.” said CERN Director-General Fabiola Gianotti.
The Human Resources (HR) department is in the process of implementing a new tool that will improve the way in which CERN recruits students, fellows, staff and associates. Modern, flexible and efficient, the SmartRecruiters software meets all the needs of CERN’s recruitment team, and its future users will put it to the test in the coming months. “It will take several months to set the software up and adapt it to CERN’s specific characteristics,” says Anne Capodici, the project leader in the HR department. “We will do that by working in close collaboration with our colleagues in the various departments in order to optimise our recruitment processes together.”
After 13 years of good, loyal service, CERN’s previous recruitment tool, e-RT, has reached the point where it no longer meets the Organization’s needs. In particular, it doesn’t have the flexibility to respond to CERN’s ever-growing recruitment requirements and lacks mobile functionality. SmartRecruiters, on the other hand, offers an intuitive and user-friendly integrated mobile recruitment platform combining all the different applications into a single package. “More and more candidates are now using their mobile devices to view and apply for job vacancies,” says Anna Cook, deputy project leader in the HR department. “So it’s essential for CERN’s recruitment system to offer a mobile platform.”
SmartRecruiters will also improve and speed up interactions between the various people involved in the recruitment process at CERN, allowing them to achieve more in less time. “Our current recruitment process is not completely standardised, which makes it slow and tedious,” Capodici explains. “SmartRecruiters will allow everyone – the employers in the departments, the HR recruiters and the candidates – to collaborate and interact efficiently by connecting to one single platform.”
With its modern design and numerous functions, the SmartRecruiters platform mirrors CERN’s image as a modern laboratory at the cutting edge of its field – an image that will no doubt attract candidates.
Participants to the CERN Accelerator School (CAS) held in in Budapest, Hungary from 2-14 October 2016.
The CERN Accelerator School (CAS) and the Wigner Research Centre for Physics in Budapest jointly organised an Introduction to Accelerator Physics course in Budapest, Hungary from 2-14 October 2016.
The course was held at the Hotel Helia and was attended by 123 participants of 28 nationalities, from countries as far away as Australia, China, Russia, South Africa and the United States.
The intensive programme comprised 42 lectures, two seminars and three tutorials. A poster session and a 1-slide/1-minute session were also included in the programme, where the students were able to present their work. Feedback from the students was very positive, praising the expertise of the lecturers, as well as the high standard and quality of their lectures.
In addition to the academic programme, the students had the opportunity to visit the Royal Palace of Visegrád and the Basilica of Esztergom. A special dinner was organised on a boat on the River Danube.
Next year CAS will be organising a specialised course on Beam Injection, Extraction and Transfer, to be held in Erice, Sicily from 10-19 March and a second specialised course on Vacuum for Particle Accelerators, to be held in Lund, Sweden from 6-16 June. The next course on Advanced Accelerator Physics will be held in the UK in the early autumn and a Joint International Accelerator School on RF Technology will be held in Hayama, Japan from 16-26 October. Further information on upcoming CAS courses can be found on the CAS website: http://www.cern.ch/schools/CAS.
Six weeks of preparation followed by a 60-hour hackathon to design and build working prototypes addressing concrete humanitarian problems: this is the challenge that eight teams accepted when they participated in the THE Port hackathon that took place from 14 to 16 October at CERN.
The interdisciplinary teams spent a long weekend building their prototypes in the cosy (and well-equipped) IdeaSquare premises. Responding to the humanitarian challenges selected, the eight teams presented just as many proposals, including a toolkit for obtaining efficient forensic photos; an app to match needs and offers of help arising after a natural disaster; a sonification and gamification device to help the user correctly execute planned exercises without the direct help of the physiotherapist; a combined solution for tracking and stopping counterfeit drugs before they are distributed to patients; a burner that can disarm unexploded bombs safely; a device designed to monitor explosions objectively via the acoustic waves they generate; a new system for disposing of waste in Field-Ready hospitals; and a machine-learning tool designed to analyse information available on the web about, for example, a major incident in order to give humanitarian workers the full picture of what happened.
Each team was able to count on the help of tutors and experts from CERN as well as partners from several non-governmental organisations based in Geneva. On the evening of 16 October, the final event at the Globe was attended by over 200 people and watched live by 180 hackathon enthusiasts.
The success of the hackathon comes as no surprise to people who have experienced it before, but was a shock to first-time participants. “It was my first hackathon and much more than I expected,” says Grace Torrellas, from the counterfeit drug reduction team. “Despite the relatively short interaction the team had during the preparation phase, the magic really sparks when there is face-to-face exchange and collaboration,” she adds.
“A unique aspect of the hackathon is that we all work together towards solving real-world problems with concrete and immediate applications,” confirms Romain Bazile, a third-time participant.
THE Port’s work does not end with the final presentations: “Our goal is to demonstrate the value of fundamental science to society,” says Daniel Dobos, one of the founders of THE Port and a member of the organising team. “We are proud to say that this year’s partners, including the ICRC, Handicap International and the Global Humanitarian Lab, have directly expressed an interest in incubating, accelerating and scaling solutions based on this weekend’s efforts.”
Even if you missed this event, you can still sign up for THE Port’s upcoming events, including UN POP UP Muse on 10 November at the Palais des Nations and the Geneva Global Goals Innovation Day on 24 March 2017. “We will also share news of the upcoming spring hackathons, including the popular Science Hackathon, soon,” adds Daniel.
A recording of the final presentations can be found here: https://cdsweb.cern.ch/record/2225856. Feel free to contact the teams if you want to contribute to the follow-up of the solution proposed or support them financially.
On 26 October, the 2016 proton-proton physics came to an end. The final integrated luminosity totals averaged around 40 fb-1 in ATLAS and CMS (whereas the target for the whole year was 25 fb-1) 1.8 fb-1 in LHCb and 13 pb-1 in ALICE. The year’s proton run also included some successful physics runs and some operation in nominal physics conditions for the forward experiments TOTEM/CT-PPS, ALFA and AFP.
At the start of the year, following the usual intensity ramp-up, the peak luminosity was already impressive, with a relatively bold initial set-up delivering significantly smaller beam sizes at the interaction points than in 2015. Peak luminosity was further improved, firstly by using smaller beams from the injectors (BCMS) and then via a reduction in the angle at which the beams cross at the interaction points of ATLAS and CMS. The resultant luminosity topped out at around 1.4 x 1034 cm-2s-1, 40% above the design value. Peak performance is nothing without consistency and perhaps the most standout feature of the year was the remarkable availability of the myriad systems and components of the LHC and its injectors. This was the result of an ongoing campaign that targets reliability and the reduction of the effects of radiation on tunnel electronics. In practice, it translated into many long and productive fills and an integrated luminosity delivery rate that went well beyond expectations.
The last couple of weeks have seen time taken out of regular operations for a number of tests that target the future performance of both the machine and the experiments. For the machine they include electron cloud measurements, beam stability investigations and preparation for higher bunch intensity. The experiments took a fill with very high pile-up (the number of proton-proton collisions per bunch crossing) and continued with checks of their luminosity calibration.
A final machine development period took place from 27 to 30 October. This is being followed by a technical stop, during which, among other things, the experiments will install special forward detectors for the upcoming proton-lead run, slated for 7 November to 4 December.
Some 120 experts attended CERN’s Cryogenic Safety Seminar last month. (Image: M. Brice/CERN)
As the home of the world’s largest cryogenic machine, the LHC, CERN is a world leader in cryogenic safety, particularly at very low temperatures. So it was natural for the HSE unit to invite cryogenic safety experts from around the world to CERN to network and share best practices. Over three days in September, 120 of these cryogenic safety experts discussed their research and the challenges they face. They mulled over regulatory frameworks and had the opportunity to visit cryogenic installations at CERN. Their discussions included Kryolize, a new CERN technology tailored for the LHC with a wide range of potential applications.
Kryolize is a software tool for sizing relief valves that protect against overpressure. It is based on international and European standards and was originally conceived to respond to the specific needs of CERN to develop valves for use with the very low temperature of liquid helium. There are some 120 tonnes of liquid helium in use at the LHC, cooling 36 000 tonnes of superconducting magnets to just 1.9 degrees above absolute zero. By developing this approach, Kryolize has filled a very important niche. “There are standards in industry, but they do not exist for the very low temperatures we work with,” explains project leader Andre Henriques. “The unique benefit of Kryolize is that you can use it for any kind of cryogenics, from liquid helium to liquid argon or nitrogen.”
Kryolize is supported by the Knowledge Transfer (KT) group, and benefits from funding from CERN’s KT Fund. Since 2015, the tool has become increasingly sought after. As a KT Fund project, experimental verification of the cryogenic parameters used within the tool, together with software development on a Graphical User Interface and harmonisation, are major goals. Excellent progress has been made on both fronts, the former via an R&D collaboration with the Karlsruhe Institute of Technology in Germany. Kryolize currently has 30 users at CERN, and six licenses have so far been granted to other research laboratories. When the project reaches its conclusion in mid-2017, Henriques anticipates a potential for applications in domains ranging from the food industry to cryogenic techniques in medicine.
CERN people were also given the chance to discover CERN’s role in cryogenic safety through discussions over a sample of ice cream, flash frozen with liquid nitrogen, to round off their lunches at Restaurant 1 on the first two days of the seminar.
Philippe Moret prepares ice cream with liquid nitrogen as HSE personnel discuss cryogenic safety with visitors to the stand. (Image: M.Brice/CERN)
After three days at CERN, seminar participants left wiser about the state-of-the-art of cryogenic safety, and with a thirst for more. “This event just shows that cryogenic safety is every bit as important as the development of new cryogenic technology,” says Henriques. CERN’s first Cryogenic Safety Seminar could be the first in an international series, ensuring that safety is fully factored in to any new project from the start.
Steffen Grohmann of KIT discusses the CERN-KIT collaboration on cryogenic safety. (Video: CERN)
Andre Henriques discusses the Kryolize project. (Video: CERN)
How entangled is our physical life today with the digital world? Personal mail and documents, private social media postings, family photos and videos, your favourite music and films... Getting a look at the hard disk of your computer might give similar insights to a tour of your house or apartment. So, the basic question is: why would anybody leave an office containing their laptop open and unlocked while nobody would ever leave their house with the door unlocked?
A short walk through any arbitrary CERN office building during lunchtime allows anyone to take an in-depth look into the private lives of our colleagues. Office doors left open. Computer screens unlocked and glowing. Owners out for lunch. Bingo — with a bit of malicious intent and some chutzpah, the curious can now sit down in your living room and marvel at your life. And we are not talking about a few isolated instances, there are plenty. Open days at home! Your full privacy sphere exposed.
Do yourself a favour: protect your privacy, protect your computer. Lock the screen when leaving your laptop unattended — in your office, at a meeting — even if you just walk away to fetch something from the printer, buy a coffee or answer a call of nature. The screen-lock is just one keystroke away: “Windows-L” for Windows PCs, “CTRL-ALT-L” on Linux systems (depending on your favourite Linux flavour), “Control+Shift+Power” on Macbooks. Also, consider protecting your laptop with a chain (a “Kensington”-lock) and locking your office with a key when you leave: it is not unusual for laptops to disappear from offices… forever.
Dennis Lo during his presentation on medical testing. (Image: TEDxCERN)
On 5 November, twelve fearless speakers explored the theme of ‘Ripples of Curiosity’ during the 4th annual TEDxCERN event, which was held in CERN’s main auditorium. In addition to the 400 creative thinkers and doers who attended the event in person, an estimate of 3800 people tuned into the live webcast from home or from one of the 75 live-viewing parties hosted in 33 countries.
The event rushed the audience through an exhilarating journey of exploration and revelation. From the depths of the ocean, through cosmos and space and time, speakers became connected to one another – confiding in how they uncovered their ideas, which started as ripples of curiosity and gradually evolved. A common theme was the notion that we should embrace (instead of fear) advancements in science, technology and health, but remain cautious as to how new technologies are employed.
“Our fear of technology comes from historical evidence for its use for inhumane purposes,” asserted Samira Hayat, a researcher developing drones and TEDxCERN speaker. “It’s not the fault of the tool… but the fault of the hand using it.”
Samira Hayat on redefining the role drones play in society. (Image: TEDxCERN)
The event also hosted several visually stunning exhibits and activities, such as the opportunity to record a one-minute TED-style talk, and an opportunity for guests to meet the speakers.
“The huge numbers of views and the feed-back was great, but to me the most gratifying aspect is to have been part of this incredible team,” said Claudia Marcelloni De Oliveira, the curator of TEDxCERN. “I love the fact that together, we created a constructive, inspirational and exciting event with topics wrongly perceived as dry.”
As the LHC moves deeper into a regime of precision heavy-ion physics, the experiments have asked for a variety of very specific operating conditions. The run will start with a period of collisions at 5.02 TeV and later increase to 8.16 TeV*, the maximum presently possible. The lower energy is chosen identical to 2013 and equivalent to that of the Pb-Pb (and some p-p) collisions in 2015. The purpose of this is to allow precise comparison among the different colliding species. This part of the run is mainly devoted to ALICE running in a special mode. At the higher energy, ATLAS, CMS, ALICE, LHCb and LHCf will all take data at the highest luminosity possible.
A great deal of preparatory engineering work, including the installation of the experiments’ Zero Degree Calorimeters – calorimeters able to distinguish between a central or peripheral ion collision – and the LHCf detectors, was done in last week’s Technical Stop. Special modifications have been made to the LHC’s beam instrumentation, beam loss monitor thresholds and injection kicker systems. The LHC cryogenics and other systems have had to recover from an interruption of the external electricity supply for a few hours on 2 November. This was done more rapidly than anticipated: beams were back in the LHC last weekend, and the intense setting-up programme could begin.
Colliding unequal beams brings new challenges to the LHC beam physics and operations teams. Protons and lead circulate at slightly different speeds and require a special cogging procedure to bring them into step for collisions at full energy.
The two beams are created from different ion sources and the LHC depends on its injector complex. Most of the accelerators in CERN are brought into play and have to reliably produce high quality beams of both types simultaneously. This also means that p-Pb operation is more vulnerable to any system failures and, indeed, there have been a number of delays. Among them, a failure of the venerable Linac 2, the present source of all CERN’s protons, delayed the start of p-Pb physics.
“Stable Beams” for physics were finally declared at 14:33 on 10 November. Next we will increase the number of bunches with the aim of providing long fills with levelled luminosity, mainly for ALICE. After some days of this, we will resume commissioning for the higher energy and maximized luminosity.
*These are the centre-of-mass energies per colliding nucleon pair and are achieved with the LHC magnets set for proton beam energies of 4 TeV and 6.5 TeV respectively.
On 25 October 2016, Linac 4 reached its design energy of 160 MeV through putting successfully into operation the 12 Pi-Mode Structures (PIMS) (Image: Federica Piccinni).
CERN’s new linear accelerator (Linac 4) has now accelerated a beam up to its design energy, 160 MeV. This important milestone of the accelerator’s commissioning phase took place on 25 October.
Linac 4 is scheduled to become the source of proton beams for the CERN accelerator complex, including the Large Hadron Collider (LHC) after the long shutdown in 2019-2020. It will replace the existing Linac 2 as the first link in the accelerator chain, which is currently accelerating protons at 50 MeV. T
he new 86-metre-long accelerator will accelerate hydrogen ions – protons surrounded by two electrons – at 160 MeV, before sending them to the Proton Synchrotron Booster (PSB). Here, the ions are stripped of their two electrons to leave only the protons that will be further accelerated before finishing their race in the LHC.
Linac 4 is comprised of four types of accelerating structures to bring particles ,over several stages, to higher and higher energies. These accelerating structures have been commissioned one by one: in November 2013, the first hydrogen ion beam was accelerated to the energy of 3 MeV, two years late the Linac 4 accelerator has reached an energy of 50 MeV – the energy Linac 2 runs at. Then, on the 1 July 2016, it crossed the 100 MeV threshold. On 25 October 2016, Linac 4 reached its design energy of 160 MeV, after successfully putting into operation the 12 Pi-Mode Structures (PIMS) built in collaboration between NCBJ (Poland), FZJ (Germany), and CERN.
In the framework of the LHC Injector Upgrade programme, a dedicated team is now working on the next step: testing the Linac 4 transfer line equipment for injection into the PSB, which will be installed in the PSB during the second long shutdown starting in 2019.
Indeed, the future injection technique in the PSB is based on an innovative principle unprecedented at CERN for proton beams. To produce the high-brightness beams required for the High-Luminosity phase of the LHC (HL-LHC), the 160 MeV hydrogen ion beam from Linac 4 will be sent onto an extremely thin carbon foil that will strip off the two electrons. The stripped beam is then sent into a special injection chicane, which allows the proton beam to circulate while injecting the hydrogen ion beam. This technique is crucial for producing the brighter and higher-quality beams necessary for the HL-LHC, but also beneficial for other experiments that make use of the PS Booster proton beam.
To test this new technique, the thin carbon foil has been inserted in a temporary installation, the Half Sector Test, installed during summer 2016 in the Linac 4 transfer line. The Half Sector Test installation is used to test the complex equipment of half of the future PSB injection chicane.
The Half Sector Test temporary installation in the Linac 4 transfer line: from right to left in the picture we can see the stripping foil system (the grey box in the foreground), the (half) injection chicane magnets (the blue structures) and the temporary beam dump (the green structure in the leftmost part of the picture).
The test facility commissioning has started right after the Linac 4 accelerated its first beam at 160 MeV and it will last until the end of March 2017. This installation will allow detailed tests of the equipment that will be installed at the injection point of the PS Booster during the second long shutdown (LS2). At the same time, other different foil materials and diagnostics are being evaluated in a permanent installation in the Linac 4 transfer line, the Stripping Foil Test Stand that will remain in place at the end of the commissioning phase.
The carbon stripping foil installed in the Half Sector Test installation. It serves to strip off two electrons from the hydrogen ions to create the proton beam that will be injected into the PS Booster.
I had a big smile on my face on the evening of Friday, 21 October 2016, when I saw how quickly the CERN IT department, the LHC experiments, teams in the accelerator sector and many more individuals were rushing to secure their Linux systems against a new and highly critical vulnerability dubbed “DirtyCow” (i.e. CVE-2016-5195). ArsTechnica labelled this bug the "most serious Linux privilege-escalation bug ever", which stresses its severity nicely, and it was too risky to go into the weekend unprotected!
It seems that computer security problems tend to occur at weekends. “DirtyCow” was a particularly nasty one that, when exploited, allows any local user to inherit administrator privileges and, subsequently, become master of the corresponding Linux system. Although CERN’s SLC5 and 6 were said to be unaffected, a few brave members of the IT department spent the Thursday evening analysing the exploitation vector in depth and finally disproved this initial statement: it turned out that SLC5 and 6, as well as CentOS7, were very much affected… Unfortunately, a prompt patch was not immediately available, so the security risk was uncomfortably high for the CERN Data Centre, its interactive computing clusters – namely LXPLUS and LXBATCH – and many other interactive Linux services in the experiments and the accelerator sector. The risk was especially high as the weekend lay ahead.
Fortunately, however, the IT department was able to propose a mitigating workaround as a temporary protective measure. Intense hours were spent on Friday preparing new Linux “system-tap kernel modules” and proving that the impact on Linux systems was minimal (in fact, only debugging functions would be affected). Finally, at around 3 p.m., the green light was given for the massive roll-out to thousands of Linux LXBATCH servers and hundreds of LXPLUS servers in the CERN Data Centre. An official warning was sent out to all relevant stakeholders at CERN, including SWAN, ATLAS, CMS and others, who promptly applied the workaround to their systems. By late night, all critical services had been secured and were ready to run through the weekend. Great job, CERN! Congratulations to you all!
Addendum: The workaround is no longer needed. CVE-2016-5195 can be fixed by deploying the most recent kernel version available from CERN Puppet or the YUM repositories. Time to bring your system up to date!
The President of the Republic of Poland, Andrzej Duda, handing CERN Director-General, Fabiola Gianotti, a book about Marie Skłodowska Curie, Polish and naturalized-French physicist and chemist. (Image: CERN)
President Andrzej Duda and his delegation were welcomed on 15 November 2016 by CERN’s Director-General, Fabiola Gianotti, and the Representative of the French Republic, sous-préfet of Gex Benoît Huber.
During the visit, the President had the opportunity to visit the CERN Control Center, the ATLAS Control Room and the underground experimental area. At the end of the visit, President Duda took the time to sign CERN’s guest book and to meet with a number of Polish members of personnel.
An overview of the NA64 experimental set-up at CERN. NA64 hunts down dark photons, hypothetic dark matter particles. (Image: Maximilien Brice/CERN)
One of the biggest puzzles in physics is that 85% of the matter in our universe is “dark”: it does not interact with the photons of the conventional electromagnetic force and is therefore invisible to our eyes and telescopes. Although the composition and origin of dark matter are a mystery, we know it exists because astronomers observe its gravitational pull on ordinary visible matter such as stars and galaxies.
The NA64 experiment – which started operations earlier this year – uses a unique set-up to hunt down a specific type of dark matter particle called the dark photon.
Some theories suggest that dark matter consists of a family of new particles and forces, just like our visible world. In addition to gravity, dark matter particles could interact with visible matter through a new force, which has so far escaped detection. Just as the electromagnetic force is carried by the photon, this dark force is thought to be transmitted by a particle called the dark photon. It is predicted to have a subtle interaction (a “mixing”, in particle physics jargon) with the regular photon and therefore act as a mediator between visible and dark matter.
“To use a metaphor, an otherwise impossible dialogue between two people not speaking the same language (visible and dark matter) can be enabled by a mediator (the dark photon), who understands one language and speaks the other one,” explains Sergei Gninenko, spokesperson for the NA64 collaboration.
“Theories predict that dark photons could also explain the longstanding discrepancy observed in measurements with muons (known as the “g-2 anomaly”). Our experiment will be able to test this, and that’s why we are so excited,” continues Gninenko.
CERN’s NA64 experiment looks for signatures of this visible-dark interaction using a simple but powerful physics concept: the conservation of energy. A beam of electrons coming from the Super Proton Synchrotron accelerator, whose initial energy is known very precisely (100 GeV), is aimed at a detector and the energy that it deposits is measured further downstream. Interactions between incoming electrons and atomic nuclei in the detector produce visible photons. If theories of dark forces are correct, however, these ordinary photons could occasionally transform into dark photons, which simply escape the detector and carry away a large fraction of the initial electron energy.
Therefore, the signature of the dark photon is an event registered in the detector with a large amount of “missing energy” that cannot be attributed to a process involving only ordinary particles, thus providing a strong hint of the dark photon’s existence.
NA64 began operations in July for a period of two weeks, and the collaboration completed a second four-week run on 9 November. Although no signs of dark photons have been found so far, the results have already set new limits on the strength of the visible-dark-matter interaction. Significantly more data accumulated in the coming years will allow the team to narrow the search further.
If confirmed, the existence of the dark photon would represent a breakthrough in our understanding the longstanding dark matter mystery.
The NA64 experiment has started operations this year to hunt for an hypothetic particle, the dark photon. (Video: Christoph Madsen/CERN)
The LHC has been key in driving development of superconducting magnets– one of the most influential technologies to come out of accelerator research and development.
These magnets are needed for energy, transport, and medical technology, applications far beyond the field of high energy physics.
High Energy physics’ thirst for superconducting magnets
At low temperatures, certain materials become superconductors. Superconducting wires can conduct 100 times the current of a traditional wire, and are at the heart of the LHC’s powerful superconducting magnets, whose magnetic field steers the beam around the accelerator ring. Dedicated large-scale research and development (R&D) programmes like the LHC, spanning over decades, are determinant for this type of technology to develop and mature. Future advances in high-field magnets will benefit both CERN projects like High Luminosity LHC (HL-LHC) and Future Circular Collider study (FCC), and might also find application further afield, such as with imaging the human brain.
Magnets for neuro-imaging and beyond
Other disciplines are also keen on R&D for novel high-field magnets. They are an integral part of the technology behind cutting-edge Magnetic Resonance Imaging (MRI) and Nuclear Magnetic Resonance (NMR) spectroscopy.
At this time, Neurospin, a research centre near Paris set up by the French Alternative Energies and Atomic Energy Commission (CEA), is investigating applications of high-field magnets for imaging the brain – or neuro-imaging. These novel technologies open a new window into our understanding of how the human brain works -- another scientific challenge for the 21st century.
Neuro-imaging studies can help understand what happens in the brain after a stroke, in ageing, and even for psychiatry and the study of mental health disorders. As our understanding of the brain evolves, advances in neuro-imaging could also contribute to developing new brain-machine interfaces, or “mind-reading technology”, that could translate brain activity measured with neuro-imaging into thoughts.
The future of high-field magnets
High-field magnets have an enormous potential for neuro-imaging technology, high energy physics and other industries, which means there is a strong incentive for collaborative R&D today. In January 2015, an ad-hoc working group called FuSuMaTech – for Future Superconducting Magnets Technology – was set up collaboratively between CERN and CEA to explore applications in high-field magnets, lower the technology barrier to make them more accessible to the market and identify potential synergies between CERN, other Academic partners, neuroimaging labs like Neurospin and European industry. For them, the HL-LHC and FCC offer an opportunity to push the European Superconducting Magnet Technology into the next decade. Together, twelve current partners are considering the Future Emerging Technologies (FET) programme of Europe’s Horizon 2020 as an opportunity to continue exploring synergies together in close collaboration with Europe’s cutting-edge superconducting magnet industry.
In the future, the HL-LHC aims to upgrade the LHC’s eight Tesla (T) magnets with cutting-edge 13T ones. Further down the line, the FCC study is exploring different designs of circular colliders for the post-LHC era. The FCC requires magnets reaching 16T or even 20T depending on its design.
These high-field magnets would enable these future colliders to reach higher energies and unprecedented luminosities, allowing further exploration of the fundamental laws of nature.
Find out more at the next Knowledge Transfer seminar: “From the Proton to the Human Brain”, 9 December 2016, by Prof. Denis Le Bihan, Director of Neurospin here.
For its last four running weeks of the year the LHC is colliding protons (p) with lead ions (Pb). This not only presents a challenge for the collider itself, but also for the six accelerators involved in producing the beams, which have to provide the bunches that will eventually collide in ALICE, ATLAS, CMS and LHCb. Two different injector chains boost and deliver the two different types of particles to the LHC. For the protons, the chain is Linac 2, the PS Booster (PSB), the Proton Synchrotron (PS) and the Super Proton Synchrotron (SPS), and for the lead ions, it’s Linac 3, the Low Energy Ion Ring (LEIR), the PS and the SPS.
The challenge for the injector complex is twofold. Firstly, the injection pattern of the protons must match with that of the lead ions, in order to maximise the number of colliding bunches in the LHC.
The ideal situation would be to have the same number of bunches and the same bunch spacing for both protons and lead ions. However, the lead ion injection technique sets a constraint. LEIR and the PS can only provide the SPS with a lead ion beam consisting of four bunches spaced by 100 nanoseconds (ns), a different pattern than in normal p-p operations where the proton beam consists of 72 bunches spaced by 25 ns.
Secondly, the intensity of the proton beam must also be reduced to correspond that of the lead ions. For p-Pb operations, the proton bunches need to be five times less intense than usual.
The best possible match that the injector team has found is to inject a train of two batches each consisting of 18 bunches of protons and a train of seven batches consisting of four bunches of lead ions (see picture for more details).
The injector chain is already benefiting from the results of the LHC Injector Upgrade (LIU) project, which aims to upgrade the beam performance of the injectors for the future High-Luminosity LHC. Since the beginning of the run, the Pb injectors have delivered an intensity three times greater than the original design value. This was a major contributor to reaching peak luminosity about six times greater than expected when the proton-lead programme was planned just a few years ago.
At the time of writing, the LHC is still on course to achieve all the physics goals of this run, in spite of all the technical mishaps encountered, such as a power cut last week and a quench on 24 November.
When not filling the LHC, the injector chain provides beams for lots of other users, including the Antiproton Decelerator, AWAKE, HiRadMat, and the North Area.
The injection scheme for the proton beam (upper part of the picture) starts with the PSB, which first sends four bunches to the PS, followed by two more 1.2 seconds later. In the PS, the bunches are then split in three and are spaced by 100 ns. The 18 resulting bunches are accelerated to 25 GeV and delivered to the SPS. This operation is repeated and the second batch of 18 bunches is injected next to the first one in the SPS, with a spacing of 200 ns. After acceleration to 450 GeV, the 36-bunch train is transferred to the LHC.For the lead ion beam (lower half of the picture): LEIR accelerates the ion beam in two bunches to 72 MeV/nucleon, and sends it to the PS. In the PS, the bunches are split in two and their spacing is set to 100 ns using an RF technique known as “batch expansion”. The accelerated beam is extracted towards the SPS and traverses a 1-mm thick aluminium foil, which strips the ions of their 28 remaining electrons. This operation is repeated six times, accumulating the seven four-bunch trains in the SPS with a spacing of 200 ns. The 28 bunches are sent to the LHC after acceleration to 177 GeV/nucleon.Due to the different bunch spacings, only the 27 blue bunches collide in each train. Each operation is repeated 20 times to fill both rings of the LHC.
The members of the ELENA project stand in front of the new decelerating ring (Image: Sophia Bennett/CERN)
With a circumference of just 30 metres, it looks a bit like a miniature accelerator. But don’t be mistaken, ELENA has all the components of a bigger machine. Tests with beam of this brand-new accelerator for antimatter experiments began in mid-November. The first beam circulated on 18 November. “Starting the machine up with beam is an interesting and crucial phase of the project. The coming weeks will show us if everything is working as planned,” explains Christian Carli, ELENA project leader.
The ELENA (Extra Low ENergy Antiproton) deceleration ring will be connected to the Antiproton Decelerator (AD) as of next year. The 182-metre-circumference AD supplies antimatter experiments with antiprotons at 5.3 MeV, the lowest energy possible in a machine of this size.
The slower the antiprotons (i.e. the less energy they have) the easier it is for the experiments to study them or to manipulate them in order to produce antihydrogen atoms, for example. ELENA will reduce the energy of antiprotons from the AD by a factor of 50, to just 0.1 MeV. In addition, the density of the beams will be improved. The number of antiprotons that can be trapped will be increased by a factor of 10 to 100, improving the efficiency of the experiments and paving the way for new experiments.
To decelerate particles, you basically need the same tools as you need to accelerate them. So ELENA is equipped with a radio-frequency cavity to decelerate the bunches of antiprotons, with dipole magnets to keep them on a circular trajectory and with focusing magnets to keep them close together and to avoid the dispersion of particles.
But at low energy and low intensity, other difficulties arise. “The beam is a lot more sensitive to external interference, such as the earth’s magnetic field, which modifies its orbit,” explains François Butin, the technical coordinator in charge of the installation.
Members of the ELENA project install componants of the new decelerator in September 2016 (Image: Maximilien Brice/ CERN)
To counteract these effects, the designers of ELENA worked on several technical parameters. The magnets were the subject of particularly intense studies, as at such low energies the magnetic fields are inevitably weak. The hysteresis of the iron in the magnet (in other words, the residual magnetism) can compromise the quality of the field. ELENA is therefore equipped with magnets that have been optimised to operate with very weak fields.
The circumference of the ring was a compromise between various constraints. It needed to be small enough to allow the magnetic fields to be more intense in order to counteract the effects of external interference, but also big enough to house all the necessary components. “The small size of the ring meant that we had to be particularly inventive as well as precise when fitting in all the components,” says François Butin.
Time-lapse video of the installation of the components. (Video: Noemi Caraban/CERN)
Another essential component of the decelerator will be its electron cooling system. When a beam is accelerated, its transverse size tends to decrease, but when it is decelerated, it increases. Electron cooling counteracts this effect by concentrating the particle bunches. The principle is to transfer transverse energy from the antiprotons to the electrons. The electron cooling system, which is in the final stages of development in the UK, will be delivered at the start of 2017.
Other challenges that had to be overcome included updating the beam instrumentation in order to be able to operate at low intensity and low energy. The vacuum system is also impressive, producing very low pressure, around 10-12 millibar.
The teams working on commissioning the machine will continue the tests with beam. In parallel, GBAR, the first experiment that will be connected to ELENA, is in the process of being assembled. GBAR will study the effect of gravity on antimatter, following in the footsteps of AEGIS and soon also ALPHA.
The other experiments will be connected during the second long shutdown of CERN’s accelerators in 2019-2020. ELENA will be able to supply antiprotons to four experiments in parallel.
Members of the CMS Create #2 team with their winning exhibit, a pinball machine (Image: CMS Create/CERN)
After a gruelling two-day workshop, the winning prototype from the CMS Create #2 competition, which will be part of the permanent CMS visit exhibition, has been chosen.
The second edition of the CMS Create workshop was hosted at IdeaSquare from 3 to 4 October 2016. Participants formed teams and competed to design prototypes that would illustrate different aspects of CMS for the public.
The winning exhibit, the “Catch me if you can” pinball machine, will soon be displayed at the CMS visit exhibition. To play it, visitors are invited to act as if they are the CMS trigger system, collecting interesting data despite having limited storage space. The prototype will be finalised by the CMS workshop at Point 5 and installed permanently on the CMS visit circuit.
Twenty-four designers, architects, software developers, physicists and engineers from 12 countries took part during the two-day event. During the event, the wide range of each team’s expertise was notable and, strikingly, an equal number of male and female scientists and designers participated. The event achieved perfect gender equality as well as great diversity.
On the first day, students from IPAC Design Genève met CERN participants at IdeaSquare to start brainstorming. The scientists and designers collaborated in teams; they had just two days to invent and construct prototypes. Despite having just met and coming from totally different backgrounds, participants started to discuss and analyse ideas quickly. By the end of the second day, the teams had to present their creation to the jury.
Outreach specialists, senior physicists and engineers from CERN advised the teams and provided their support and guidance. During the workshop, the IPAC students developed their understanding of the scientific content and the CERN participants focused on how to communicate concept to the public. IdeaSquare, in collaboration with THE Port, provided them with the mechanical tools, electronics and other rapid prototyping facilities needed to bring theory into practice.
Following two days of intensive work, the participants presented their creations to the CMS Create #2 jury, composed of: Ana Godinho, CERN’s Education, Communication and Outreach Group Leader; Dr Jay Hauser, senior physicist at CMS; Suzanne Freitas, Communication and Interactive Design Professor at IPAC; and Laurent Chateaux, Head of the Tourism Office of Gex, La Faucille.
Samira Hayat on redefining the role drones play in society. (Image: TEDxCERN)
