European Organization for Nuclear Research: Appointments

CERN@school is a program that brings CERN, the European Organisation for Nuclear Research, into the classroom. By supplying schools with cutting-edge detector technology and giving them access to the Worldwide LHC Computing Grid, students in the United Kingdom are being offered the opportunity to conduct authentic research in the field of nuclear and particle physics. Thanks to the support of the Science and Technology and Facilities Council (STFC), the Royal Commission for the Exhibition of 1851, and the Institute of Physics, the program has resulted in a nationwide network of student scientists working together to conduct a number of research projects. This article looks at how CERN@school has achieved this, some of the ongoing experiments, and the potential for rolling out the approach across the world.

In Britain, the Council of the recently amalgamated Institute of Physics and Physical Society has announced that it has made three awards, one of which has been received by an American physicist. Scott E. Forbush, mathematical physicist on the staff of the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, was named to receive the Charles Chree Medal and Prize for distinguished contributions in the study of cosmic radiation. The other award winners are J. B. Adams, director-general of the European Organization for Nuclear Research, who has been given the Duddell Medal for his leadership of the CERN team, and A. W. Merrison, professor of experimental physics in the Nuclear Physics Research Laboratory of the University of Liverpool, who received the Charles Vernon Boys Prize for distinguished research in experimental physics.

The National Institute for Nuclear Physics (INFN) is developing at the Laboratory of Accelerators and Applied Superconductivity (LASA) laboratory (Milano, Italy) the prototypes of five corrector magnets, from skew quadrupole to dodecapole, which will equip the high-luminosity interaction regions of the High Luminosity Large Hadron Collider (HL-LHC). These magnets are based on a superferric design, which allows a relatively simple, compact, and easy to construct magnet. This activity takes place within the framework of a collaboration agreement between European Organization for Nuclear Research (CERN) and INFN. The first prototypes, a sextupole and an octupole, have been tested in 2016 and 2017, respectively. We present here the results of the cold tests of the decapole that has been assembled and tested in the second half of 2017, including the training performed at 4.2 K and the qualification at 2.17 K. We report also on the overall experience gained during construction and tests and the improvements toward the series production. Other important results concern quench studies.

Abstract. Cloud microphysical processes involving the ice phase in tropospheric clouds are among the major uncertainties in cloud formation, weather, and general circulation models. The detection of aerosol particles, liquid droplets, and ice crystals, especially in the small cloud particle-size range below 50 μm, remains challenging in mixed phase, often unstable environments. The Cloud Aerosol Spectrometer with Polarization (CASPOL) is an airborne instrument that has the ability to detect such small cloud particles and measure the variability in polarization state of their backscattered light. Here we operate the versatile Cosmics Leaving OUtdoor Droplets (CLOUD) chamber facility at the European Organization for Nuclear Research (CERN) to produce controlled mixed phase and other clouds by adiabatic expansions in an ultraclean environment, and use the CASPOL to discriminate between different aerosols, water, and ice particles. In this paper, optical property measurements of mixed-phase clouds and viscous secondary organic aerosol (SOA) are presented. We report observations of significant liquid–viscous SOA particle polarization transitions under dry conditions using CASPOL. Cluster analysis techniques were subsequently used to classify different types of particles according to their polarization ratios during phase transition. A classification map is presented for water droplets, organic aerosol (e.g., SOA and oxalic acid), crystalline substances such as ammonium sulfate, and volcanic ash. Finally, we discuss the benefits and limitations of this classification approach for atmospherically relevant concentrations and mixtures with respect to the CLOUD 8–9 campaigns and its potential contribution to tropical troposphere layer analysis.

CARLOSv3 is the third version of a chip that plays a significant role in the data acquisition chain of the A Large Ion Collider Experiment (ALICE) silicon drift detector (SDD). ALICE is one of the foremost high-energy physics experiments (HEPE) conducted within the Large Hadron Collider at CERN, the European Organization for Nuclear Research in Geneva. CARLOSv3 was principally designed and built for the on-line compression of the input dataset originating from a physical bidimensional silicon sensor. To compress a bidimensional dataset, a bidimensional data compressor was required. The compressor was designed for the ALICE SDD Experiment but could be applied to all experiments in which an incoming stream dataset originates from a bidimensional sensor.

Based at CERN, the European Organization for Nuclear Research, the Large Hadron Collider (LHC) is the world's largest and most powerful particle accelerator. From 2025, the LHC will be upgraded to allow it to achieve a factor of 10 higher luminosity, which increases the rate of collisions, essential for probing new physics phenomena in the future. The route to high luminosity LHC (HL-LHC) involves various detector upgrades and requires significant infrastructure changes. Recent measurements by CERN Radiation Protection, verifying previous calculations by The University of Sheffield (UoS), has raised awareness about the need to restrict human activity in the HL-LHC experimental, construction and maintenance areas due to exposure from high levels of radiation. Examining the case of the ATLAS detector upgrade, the collaborative partnership between UoS and UK industry is developing state-of-the-art robotic instrumentation, capable of tolerating high radiation levels. The main object of this research is a feasibility study with a TRL (technology readiness level) of three, to determine how materials and sub components of dexterous robotic systems behave after exposure to high levels of radiation. This is evaluation uses novel robotic irradiation equipment, techniques and test methods housed in the Birmingham University (UK) Irradiation Facility. One finger of an unmodified Shadow Robot Company “Hand”, a highly dexterous robotic manipulator, was exposed to specific doses of high radiation in a temperature controlled thermal chamber. Cooled by a liquid nitrogen evaporative system, the irradiation system moves samples continuously through a homogeneous proton beam. Movement is provided by a radiation hard pre-configured XY-Axis Cartesian Robot. The methods and techniques developed as a result of this TRL3 research will further aid the application and deployment of robotic and autonomous systems into highly radioactive environments. Based on preliminary findings it has been concluded that finger materials and basic electrical components can tolerate hazardous radiation environments, with careful selection and substitution of a minimal amount of materials, radiation hardness is also possible. Further work is scheduled for the irradiation of a fully instrumented and powered robotic hand to determine working hour tolerance.

This work is devoted to a feasibility analysis for the development of fiber optic humidity sensors to be applied in high-energy physics applications and in particular in the experiments actually running at the European Organization for Nuclear Research (CERN). On this line of argument, due to the wide investigations carried out in the last years aimed to assess the radiation hardness capability of fiber optic technology in high energy physics environments, our multidisciplinary research group has been recently engaged in the development and assessment of fiber optic sensors based on polyimide-coated Fiber Bragg Gratings (FBGs) to perform relative humidity (RH) monitoring at temperatures below 0°C as well as in presence of strong ionizing radiations. Data here reported, obtained during a deep experimental campaign carried out in the laboratories of CERN, demonstrate the amazing RH sensing properties of such sensors in the temperature range -15-20°C as well as their radiation hardness capability up to (at least) 10kGy dose of ionizing radiations.

One of the most striking features of the postwar development of high-energy physics has been the growth of large teams of physicists on the experimental workfloor. Before the war experimental research, even with big accelerators like that at Berkeley, was generally done with relatively simple equipment, and remained an essentially individual affair (1). However, as detectors became more complex, costly, and time-consuming to build, increasing numbers of physicists from different institutions and from different countries began to do experiments together with the device. This phenomenon emerged in the late 1950s, and the size and multinationality of teams has tended to grow ever since. Very roughly, the number of physicists in a collaboration taking data with the largest detectors used in high-energy physics has been doubling every five or six years since the mid-1960s, and might reach 1,000 by the year 2000 (2). At the same time collaborations in high-energy physics have become major foci for international scientific work. A typical paper from one of CERN’s (the European Organization for Nuclear Research) largest detectors was recently signed by 521 people from 44 institutes in 19 countries.KeywordsBubble ChamberCentral DetectorLarge TeamQueen Mary CollegeBritish GroupThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

A moderator-type neutron monitor containing pairs of TLD 600/700 elements (Harshaw) modified with the addition of a lead layer (GSI ball) for the measurement of the ambient dose equivalent from neutrons at medium- and high-energy accelerators, is introduced in this work. Measurements were performed with the Gesellschaft für Schwerionenforschung (GSI) ball as well as with conventional polyethylene (PE) spheres at the high-energy accelerator SPS at European Organization for Nuclear Research [CERN (CERF)] and in Cave A of the heavy-ion synchrotron SIS at GSI. The measured dose values are compared with dose values derived from calculated neutron spectra folded with dose conversion coefficients. The estimated reading of the spheres calculated by means of the response functions and the neutron spectra is also included in the comparison. The analysis of the measurements shows that the PE/Pb sphere gives an improved estimate on the ambient dose equivalent of the neutron radiation transmitted through shielding of medium- and high-energy accelerators.

This paper describes the development of a sensor designed to detect low concentrations of hydrogen fluoride (HF) in gas mixtures. The sensor employs a plastic optical fiber (POF) covered with a thin layer of glass- like material. HF attacks the glass and alters the fiber transmission capability so that the detection simply requires a LED and a photodiode. The coated POF is obtained by means of low-pressure plasma-enhanced chemical vapor deposition that allows the glass-like film to be deposited at low temperature without damaging the fiber core. The developed sensor will be installed in the recirculation gas system of the resistive plate chamber muon detector of the Compact Muon Solenoid experiment at the Large Hadron Collider accelerator of the European Organization for Nuclear Research (CERN).

European Web Sites to Watch: The European Organization for Nuclear Research, CERN

A well-attended meeting, called "Brainstorming discussion for a possible biomedical facility at CERN", was held by the European Organization for Nuclear Research (CERN) at the European Laboratory for Particle Physics on 25 June 2012. This was concerned with adapting an existing, but little used, 78-m circumference CERN synchrotron to deliver a wide range of ion species, preferably from protons to at least neon ions, with beam specifications that match existing clinical facilities. The potential extensive research portfolio discussed included beam ballistics in humanoid phantoms, advanced dosimetry, remote imaging techniques and technical developments in beam delivery, including gantry design. In addition, a modern laboratory for biomedical characterisation of these beams would allow important radiobiological studies, such as relative biological effectiveness, in a dedicated facility with standardisation of experimental conditions and biological end points. A control photon and electron beam would be required nearby for relative biological effectiveness comparisons. Research beam time availability would far exceed that at other facilities throughout the world. This would allow more rapid progress in several biomedical areas, such as in charged hadron therapy of cancer, radioisotope production and radioprotection. The ethos of CERN, in terms of open access, peer-reviewed projects and governance has been so successful for High Energy Physics that application of the same to biomedicine would attract high-quality research, with possible contributions from Europe and beyond, along with potential new funding streams.

Certain magnet power supplies for particle accelerators demand a high consumption of pulsed power, which generates perturbations in the electrical grids located in urban zones. Power supply systems with integrated local energy storage elements are under consideration as alternatives to mitigate these disturbances. Due to elevated magnitudes in the load current, a parallel association of full-bridge structures is proposed to control the energy flow between the storage units and the load. Different modulation methods and interleaved control techniques are used. In the present work, different strategies are analyzed in a comparative study, with the purpose of defining the most suitable one for the operational characteristics considered for both, the load and the storage elements. Simulations on a future power converter to be used in the High-Luminosity Large Hadron Collider (HL-LHC) at the European Organization for Nuclear Research (CERN) are presented.

Chapter 5 The relationship between CERN and its ‘visitors’ in the 1970s

The Large Hadron Collider (LHC) [1] is a two-ring superconducting hadron accelerator and collider located at the European Organization for Nuclear Research (CERN) center at the French-Switzerland border. The LHC is installed in the 27 km tunnel constructed for the Large Electron Positron Collider (LEP) experiment [2] which lies between 45 and 170 m below ground. In 1996, the construction of a 14 TeV LHC was approved [3]. The LEP experiment ran from 1989 to 2000 when it was closed to liberate the tunnel for the LHC. While the LEP experiment collided electrons and positrons, the LHC primarily collides bunches of protons at four interaction points around the ring where four independent experiments are located: ATLAS [4], CMS [5], LHCb [6], and ALICE [7]. ATLAS and CMS are general purpose detectors aiming to run at high luminosities, with peak luminosity of \(L = 2\times 10^{34} \text { cm}^{-2}\text { s}^{-1}\). LHCb is designed to study b-hadrons with peak luminosity of \(L = 2\times 10^{32} \text { cm}^{-2}\text { s}^{-1}\) and ALICE is designed to study heavy ion collisions with peak luminosity of \(L = 2\times 10^{27} \text { cm}^{-2}\text { s}^{-1}\). The LHC complex and the four experiments are shown in Fig. 3.1.