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In this paper, we employ Ian Hacking's insight that "unity" has a double meaning, singleness and harmonious integration, to revisit a major episode from the recent history of CERN: the UA1 and UA2 experiments in the early 1980s, which led to the discovery of the W and Z bosons. CERN is a complex institution, where diverse groups are called upon to cooperate. We argue that this lack of unity, in the first sense of the term, is counterbalanced by specific mechanisms of integration, so that CERN achieves its standing as a unified organization. The UA1/UA2 episode highlights this interplay between unity and disunity. The UA2 experiment was designed and carried out in order to confirm the validity of the results obtained by UA1. The two experimental teams, working independently and with different mentalities, built separate detectors and refrained from systematically sharing their data. This gave rise to strong antagonisms and diametrically opposed opinions over what conclusions could legitimately be drawn from the resulting data. Our analysis focuses on the mechanisms which compensated for that disunity and eventually led to a unified consensus between UA1 and UA2. [ABSTRACT FROM AUTHOR]

Summary: CERN operates one of the most complex particle accelerator facilities in the world. Several different hazards, including fires, are present and need to be investigated and reduced to a tolerable level. Toward this goal, CERN aims at developing a catalog containing detailed fire dynamics descriptions of combustible items present in its facilities. This paper contributes to this catalog in two ways. First, through the development of a design fire calculator for electrical cabinets that allows the determination of potential design fire curves for any number of electrical cabinets/racks. The second contribution was to experimentally characterize the smoke production rates and smoke particle properties of the most common cables and insulating oils used at CERN by coupling a fast particle mobility analyzer to a cone calorimeter. The two particle size modes (accumulation and nucleation mode) could be linked to the fire properties and heat release rate. Accumulation mode particles (~200 nm) were associated with high heat release rates and high soot emissions from the flame. This study identifies a necessity to consider ultrafine particle emissions with low mass emissions but high number emissions in relation to risk assessments pertaining to nuclear facilities and dispersion of radioactive aerosols to the surrounding environment. [ABSTRACT FROM AUTHOR]

This essay-poem develops the author's ongoing transdisciplinary examination of her integrated artistic practice and theory known as 'quantum poetics', investigating shared principles in poetry and science with the aim of reinventing common notions of spacetime, language, and reality. Topics touched upon include her research in particle physics at the European Organization for Nuclear Research (CERN) and Canfranc Underground Laboratory, the uncertainty principle in quantum theory and aesthetic ambiguity, Werner Heisenberg's essays on language and science, the reader of a literary text in relation to an observation in quantum theory, string theory and poetry, the asymmetry of matter and antimatter in the known universe in relation to the imagination, and the poethics of science. Using a cross-genre form that includes poetry, creative nonfiction, and academic scholarship identified as an essay-poem, the author writes in 'windows', justified text blocks that transition into and out of original poetry and quoted material by writers and scientists. One purpose of these windows is to treat the spacetime of the page as a literary device, one that visually foregrounds the material construct of literary language. [ABSTRACT FROM AUTHOR]

İleri Hadron (HF) dedektörü, Compact Muon Solenoid (CMS) deneyinin her iki yanında bulunup, CMS'nin çok ileri bölgedeki pseudorapidite (3.0 < | η | < 5.0) aralığını kapsar. Her bir HF modülü, demir soğurucuların uzunluğu boyunca ışın demeti eksenine paralel uzanan kuvars liflerinden yapılmıştır. HF, ışın eksenine yakın olduğu için yüksek düzeyde radyasyona maruz kalır. Ve yüksek radyasyon etkisi nedeniyle, kuvars fiberler zamanla bozulmaya başlar. Bu radyasyon etkisini belirlemek için HF detektörüne bazı özel fiberler yerleştirilmiştir. Radyasyonun neden olduğu hasarı izlemek için toplam 56 fiber kanalı kullanılmıştır. Bu çalışma, HF'nin radyasyon hasarının izlenmesi için 2010 yılı çalışma döneminde alınan yerel lazer verileri kullanılarak yapılmıştır. Belirli bir pseudorapidite ve azimutal açıda RadDam kanallarında önemli bir radyasyon hasarı gözlenmemiştir.

Particle accelerators and detectors are used in physics research to explore big existential questions. What are we made of? What forces govern the Universe? What is its origin story? Why do particles have mass? Scientists at CERN, home of the largest particle collider accelerator, use some of the most complex instruments and technologies to answer these questions. Often the scientific and technological advancements originated at CERN can have applications in areas with a more direct impact in our lives. But the trajectory between CERN’s accelerators, detectors and computing systems and their potential industrial applications is not a linear one. It requires an exceptional skillset at CERN and beyond, highly customised tools, and the right mix of professionals and self-made opportunities.

Challenge Based Innovation (CBI) is a university programme where student teams create innovative design projects in collaboration with CERN. Each university participating in CBI creates its version of the program. Thus, this is not a closed program, but open to different curricula, periods and student backgrounds. Despite the impact on the participants and potential of the program, it is not as internationally recognised as it could be. This paper presents results of an experimental project that rebrands and redesigns the graphic identity of CBI in order to increase its recognition, better communicate its goals and project outcomes. The process involved an understanding of the problem, provided by interviews with the main stakeholders, along with the identity development attained through brainstorming, sketching, experimental prototyping and iterating. The result aims to be a distinct modular brand, that represents the openness of the programme and its connection with technology and society.

Inspector and Inspector Services framework are innovative developer tools, designed at CERN and used for the design of control applications at the CERN accelerator complex. This paper presents the use of this framework in the implementation of an application that permits fast emittance reconstruction from profile measurements at Linac3 using the quadrupole variation method. The theoretical background is presented along with measurements, simulations, error analysis and technical characteristics of the application and software platform. [ABSTRACT FROM AUTHOR]

The use of radioactivity in medicine has been developed over a century. The discovery of radioisotopes and their interactions with living cells and tissue has led to the emergence of new diagnostic and therapeutic modalities. The CERN-MEDICIS infrastructure, recently inaugurated at the European Center for Nuclear Research (CERN), provides a wide range of radioisotopes of interest for diagnosis and treatment in oncology. Our objective is to draw attention to the progress made in nuclear medicine in collaboration with CERN and potential future applications, in particular for the treatment of aggressive tumors such as pancreatic adenocarcinoma, through an extensive review of literature. Fifty seven out of two hundred and ten articles, published between 1997 and 2020, were selected based on relevancy. Meetings were held with a multi-disciplinary team, including specialists in physics, biological engineering, chemistry, oncology and surgery, all actively involved in the CERN-MEDICIS project. In summary, new diagnostic, and therapeutic modalities are emerging for the treatment of pancreatic adenocarcinoma. Targeted radiotherapy or brachytherapy could be combined with existing therapies to improve the quality of life and survival of these patients. Many studies are still in the pre-clinical stage but open new paths for patients with poor prognosis.

The CERN-MEDICIS (MEDical Isotopes Collected from ISolde) facility has delivered its first radioactive ion beam at CERN (Switzerland) in December 2017 to support the research and development in nuclear medicine using non-conventional radionuclides. Since then, fourteen institutes, including CERN, have joined the collaboration to drive the scientific program of this unique installation and evaluate the needs of the community to improve the research in imaging, diagnostics, radiation therapy and personalized medicine. The facility has been built as an extension of the ISOLDE (Isotope Separator On Line DEvice) facility at CERN. Handling of open radioisotope sources is made possible thanks to its Radiological Controlled Area and laboratory. Targets are being irradiated by the 1.4 GeV proton beam delivered by the CERN Proton Synchrotron Booster (PSB) on a station placed between the High Resolution Separator (HRS) ISOLDE target station and its beam dump. Irradiated target materials are also received from external institutes to undergo mass separation at CERN-MEDICIS. All targets are handled via a remote handling system and exploited on a dedicated isotope separator beamline. To allow for the release and collection of a specific radionuclide of medical interest, each target is heated to temperatures of up to 2,300°C. The created ions are extracted and accelerated to an energy up to 60 kV, and the beam steered through an off-line sector field magnet mass separator. This is followed by the extraction of the radionuclide of interest through mass separation and its subsequent implantation into a collection foil. In addition, the MELISSA (MEDICIS Laser Ion Source Setup At CERN) laser laboratory, in service since April 2019, helps to increase the separation efficiency and the selectivity. After collection, the implanted radionuclides are dispatched to the biomedical research centers, participating in the CERN-MEDICIS collaboration, for Research & Development in imaging or treatment. Since its commissioning, the CERN-MEDICIS facility has provided its partner institutes with non-conventional medical radionuclides such as Tb-149, Tb-152, Tb-155, Sm-153, Tm-165, Tm-167, Er-169, Yb-175, and Ac-225 with a high specific activity. This article provides a review of the achievements and milestones of CERN-MEDICIS since it has produced its first radioactive isotope in December 2017, with a special focus on its most recent operation in 2020.

The cooling systems of the future tracking detectors of the ATLAS and CMS experiments at the Large Hadron Collider (LHC) at CERN will be entirely based on CO2 refrigeration technology. The system is a booster refrigeration system, composed of a two stage primary part with transcritical R744 equipment and a low temperature secondary CO2 pumped loop. The primary refrigeration sub-system installed on surface provides cold R744 at − 53 ∘ C to the CO2 pumped loops installed 100 m underground and rejects the heat exchanged. The process must be reliable and remain stable regardless of the amount of heat exchanged, which will amount to hundreds of kilowatts and is expected to vary throughout the lifetime of the detectors. The paper discusses the concept adopted for the innovative transcritical R744 cycle and describes the technical details of the first prototype built. [ABSTRACT FROM AUTHOR]

This article presents the results of a comprehensive characterization of special radiation-resistant multimode optical fibers, including complementary irradiation tests during mass production. Radiation-induced attenuation measurements were carried out at different wavelengths and the attenuation behavior studied with varying the dose rate. Following a preliminary qualification performed upstream the production, CERN, the European Organization for Nuclear Research, validated the procurement of 500 km of fiber for installation in the accelerator complex and experiments. A strict quality assurance plan, including quality control and irradiation tests, was implemented for monitoring the characteristics of the supplied optical fibers all along the production process. The results show resistance to radiations consistently below 60 dB/km for a total dose of 10 kGy and a dose rate of 0.2 Gy/s and stable optical performance over hundreds of fiber spools produced during a 6-year period. [ABSTRACT FROM AUTHOR]

Bespoke Cost Monitoring software collates data on the performance of all aspects of the ATLAS experiment's High Level Trigger software. These data are exported for subsequent analysis offline, and are used to understand the resource usage of the individual trigger selections in terms of the amount of CPU time and the amount of raw detector data which was required to perform the selection. For the LHC's Run 3, the ATLAS High Level Trigger is re-implemented in a multi-threaded framework with both intra-event and inter-event algorithm parallelism. We will describe some of the complications and considerations which arise from monitoring event metrics in a highly parallel environment. [ABSTRACT FROM AUTHOR]

The LHCb experiment at the Large Hadron Collider (LHC) at CERN has successfully performed a large number of physics measurements during Runs 1 and 2 of the LHC. Monte Carlo simulation is the key to the interpretation of these and future measurements. The LHCb experiment is currently undergoing a major detector upgrade for Run 3 of the LHC to process events with five times higher luminosity. New simulation software technologies have to be introduced to produce simulated data samples of sufficient size within the computing resources allocated for the next few years. Therefore, the LHCb collaboration is currently preparing an upgraded version of its Gauss simulation framework. The new version provides the LHCb specific functionality while its generic simulation infrastructure has been encapsulated in an experiment independent framework, Gaussino. The latter combines the Gaudi core software framework and the Geant4 simulation toolkit and fully exploits their multi-threading capabilities. A prototype of a fast simulation interface to the simulation toolkit is being developed as the latest addition to Gaussino to provide an extensive palette of fast simulation models, including new deep learning-based options. [ABSTRACT FROM AUTHOR]

Over the years, research into debugging distributed systems with message passing communication has focused on verifying the implementation of functionality, such as race condition detection, and not on the exchanged data. In this paper we explore this previously undervalued approach. We present a new component to gather exchanged messages. We create a simplified model of message passing and the component's design based on it. Then, we discuss how to utilise the component to create tools which provide currently missing debugging information. In the end, we implement the component as part of the O² framework and conduct benchmarks. We obtain promising results - the component does not decrease the throughput. [ABSTRACT FROM AUTHOR]