Superfluid helium cryogenics for the Large Hadron Collider project at CERN (original) (raw)
Related papers
The large hadron collider project
Fusion Engineering and Design, 1999
The Large Hadron Collider (LHC), approved by the CERN Council in December 1994, will be the premiere research tool at the energy frontier of particle physics. It will provide proton-proton collisions with a centre-of-mass energy of 14 TeV and an unprecedented luminosity of 10 34 cm-2 s-1. The most critical technologies of the LHC are the superconducting magnet system, with a dipole field above 8 Tesla, and the huge cryogenic system operating at below 2 K needed to achieve such high fields. A brief overview of the project is presented and the main technological challenges are discussed.
LHC accelerator physics and technology challenges
Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)
The Large Hadron Collider (LHC) incorporates many technological innovations in order to achieve its design objectives at the lowest cost. The two-in-one magnet design, with the two magnetic channels integrated into a common yoke, has proved to be an economical alternative to two separate rings and allows enough free space in the existing (LEP) tunnel for a possible future reinstallation of a lepton ring for e-p physics. In order to achieve the design energy of 7 TeV per beam, with a dipole field of 8.3 T, the superconducting magnet system must operate in superfluid helium at 1.9 K. The LHC will be the first hadron machine to produce appreciable synchrotron radiation which, together with the heat load due to image currents, has to be absorbed at cryogenic temperatures. A brief review of the machine design is given and some of the main technological and accelerator physics issues are discussed.
The Large Hadron Collider-present status and prospects
IEEE Transactions on Appiled Superconductivity, 2000
The Large Hadron Collider (LHC), due to be commissioned in 2005, will provide particle physics with the first laboratory tool to access the energy frontier above 1 TeV. In order to achieve this, protons must be accelerated and stored at 7 TeV, colliding with an unprecedented luminosity of 10 34 cm-2 s-1. The 8.3 Tesla guide field is obtained using conventional NbTi technology cooled to below the lambda point of helium. Considerable modification of the infrastructure around the existing Large Electron Positron collider (LEP) tunnel is needed to house the LHC machine and detectors. A brief status report is given and future prospects are discussed.
Advanced technology issues in the LHC project
1994
The LHC (Large Hadron Collider) project is based on a pair of superconducting storage rings to be installed in the LEP tunnel. The primary objective of the machine is to provide proton-proton collisions with a centre of mass energy of 14 TeV and an unprecedented luminosity of lO34 cmm2 s-l. It will also provide colliding beams of Pb ions and
European Physical Journal - Special Topics, 2019
Particle physics has arrived at an important moment of its history. The discovery of the Higgs boson, with a mass of 125 GeV, completes the matrix of particles and interactions that has constituted the “Standard Model” for several decades. This model is a consistent and predictive theory, which has so far proven successful at describing all phenomena accessible to collider experiments. However, several experimental facts do require the extension of the Standard Model and explanations are needed for observations such as the abundance of matter over antimatter, the striking evidence for dark matter and the non-zero neutrino masses. Theoretical issues such as the hierarchy problem, and, more in general, the dynamical origin of the Higgs mechanism, do likewise point to the existence of physics beyond the Standard Model. This report contains the description of a novel research infrastructure based on a high-energy hadron collider, which extends the current energy frontier by almost a factor 2 (27 TeV collision energy) and an integrated luminosity of at least a factor of 3 larger than the HL-LHC. In connection with four experimental detectors, this infrastructure will deepen our understanding of the origin of the electroweak symmetry breaking, allow a first measurement of the Higgs self-coupling, double the HL-LHC discovery reach and allow for in-depth studies of new physics signals arising from future LHC measurements. This collider would directly produce particles at significant rates at scales up to 12 TeV. The project re-uses the existing LHC underground infrastructure and large parts of the injector chain at CERN. This particle collider would succeed the HL-LHC directly and serve the world-wide physics community for about 20 years beyond the middle of the 21st century. The European Strategy for Particle Physics (ESPP) update 2013 stated “To stay at the forefront of particle physics, Europe needs to be in a position to propose an ambitious post-LHC accelerator project at CERN by the time of the next Strategy update”. The FCC study has implemented the ESPP recommendation by developing a vision for an “accelerator project in a global context”. This document describes the detailed design and preparation of a construction project for a post-LHC circular high-energy hadron collider “in collaboration with national institutes, laboratories and universities worldwide”, and enhanced by a strong participation of industrial partners. Now, a coordinated preparation effort can be based on a core of an ever-growing consortium of already more than 135 institutes worldwide. The technology for constructing a High-Energy LHC can be brought to the technology readiness level required for construction within the coming ten years through a committed and focused R&D; programme. The concept comprises a power-saving, low-temperature superconducting magnet system based on an evolution of the Nb3Sn technology pioneered at the HL-LHC, an energy-efficient cryogenic refrigeration infrastructure based on a neon-helium (Nelium) light gas mixture, a high-reliability and low loss cryogen distribution infrastructure based on Invar, high-power distributed beam transfer using superconducting elements and local magnet energy recovery and re-use technologies that are already gradually introduced at other CERN accelerators. Re-use of the LHC underground civil infrastructure worth about 500 million CHF at the time of its construction, extension of the surface sites and use of the existing injector chain that also serve for a concurrently running physics programme are levers to come to a sustainable research infrastructure at the energy frontier. Strategic R&D; for HE-LHC aims at minimising construction cost and energy consumption, while maximising the socio-economic impact. It needs to mitigate technology-related risks and ensure that industry can benefit from an acceptable economic utility. Concerning the implementation, a preparatory phase of about eight years is both necessary and adequate to establish the project governance and organisation structures, to build the international machine and experiment consortia, to develop a territorial implantation plan considering the constraints emerging from using the existing infrastructure and the host states’ requirements, optimising the use of land, resources and preparing the construction project. Such a large-scale, international fundamental research infrastructure, tightly involving industrial partners and providing training at all education levels, will be a strong motor of economic and societal development in all participating nations. The FCC study has implemented a set of actions towards a coherent vision for the world-wide high-energy and particle physics community, providing a collaborative framework for topically complementary and geographically well-balanced contributions. This conceptual design report lays the foundation for a subsequent infrastructure preparatory and technical design phase.
The commissioning of the instrumentation for the LHC tunnel cryogenics
2007
The Large Hadron Collider (LHC) at CERN is a superconducting accelerator and proton-proton collider of circumference of 27 km, lying about 100 m underground. Its operation relies on 1232 superconducting dipoles with a field of 8.3 T and 392 superconducting quadrupoles with a field gradient of 223 T/m powered at 11.8 kA and operating in superfluid helium at 1.9 K.
Introduction to the HL-LHC Project
2015
The Large Hadron Collider (LHC) is one of largest scientific instruments ever built. It has been exploring the new energy frontier since 2010, gathering a global user community of 7,000 scientists. To extend its discovery potential, the LHC will need a major upgrade in the 2020s to increase its luminosity (rate of collisions) by a factor of five beyond its design value and the integrated luminosity by a factor of ten. As a highly complex and optimized machine, such an upgrade of the LHC must be carefully studied and requires about ten years to implement. The novel machine configuration, called High Luminosity LHC (HL-LHC), will rely on a number of key innovative technologies, representing exceptional technological challenges, such as cutting-edge 11–12 tesla superconducting magnets, very compact superconducting cavities for beam rotation with ultra-precise phase control, new technology for beam collimation and 300-meter-long high-power superconducting links with negligible energy di...