학술논문

The LHC magnet string programme: status and future plans
Document Type
Conference
Source
Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366) Particle accelerator conference Particle Accelerator Conference, 1999. Proceedings of the 1999. 5:3203-3205 vol.5 1999
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Nuclear Engineering
Robotics and Control Systems
Large Hadron Collider
Apertures
Superconducting magnets
Cryogenics
Power system protection
Elementary particle vacuum
Vacuum systems
Design optimization
Fatigue
High temperature superconductors
Language
Abstract
String 1, with one twin aperture quadrupole and three twin aperture 10-m dipoles (MB1, MB2 and MB3) powered in series and operating at 1.9 K, has recently been dismantled after four years of operation interrupted by technical stops and shutdowns for upgrading or exchanging equipment. Following the validation of the main LHC systems (cryogenics, magnet protection, vacuum, powering and energy extraction) the experimental programme was oriented towards the optimisation of the design and the observation of artificially induced fatigue effects. The design study for String 2 has been completed. This facility, which will be commissioned in December 2000, is composed of two LHC half-cells each consisting of one twin aperture quadrupole and three 15-m twin aperture dipoles. A cryogenic distribution line housing the supply and recovery headers runs parallel to the string of magnets. An electrical feedbox is used to power, with high temperature superconductor current leads, the circuits as in the regular part of an LHC arc. This paper reviews the experiments carried-out with String 1 and summarises the results obtained after more than 12800 hours of operation below 1.9 K and 172 quenches. It also describes the layout and the components of String 2 and explains the objectives pursued by its designers.