Commissioning of Ramp and Squeeze at the Lhc
نویسندگان
چکیده
The energy ramp and the betatron squeeze at the CERN Large Hadron Collider (LHC) are particularly critical operational phases that involve the manipulation of beams well above the safe limit for damage of accelerator components. In particular, the squeeze is carried out at top energy with reduced quench limit of superconducting magnets and reduced aperture in the triplet quadrupoles. In 2010, the commissioning of the ramp from 450 GeV to 3.5 TeV and the squeeze to 2 m in all the LHC experiments have been achieved and smoothly became operational. In this paper, the operational challenges associated to these phases are discussed, the commissioning experience with singleand multi-bunch operation is reviewed and the overall performance is discussed
منابع مشابه
Feed-forward in the Lhc
The LHC operational cycle is comprised of several phases such as the ramp, the squeeze and stable beams. During the ramp and squeeze in particular, it has been observed that the behaviour of key LHC beam parameters such as tune, orbit and chromaticity is highly reproducible from fill to fill. To reduce the reliance on the crucial feedback systems, it was decided to perform fill-to-fill feedforw...
متن کاملCommissioning and First Performance of the Lhc Beam Instrumentation
This paper will outline the progress with LHC commissioning to date, detailing the performance achieved with all the main LHC beam instrumentation systems. It will include an overview of the beam loss system and its role in machine protection, along with that of the beam position system and its use for automatic orbit control. Results will be shown from the highly sensitive base band tune syste...
متن کاملLhc Online Chromaticity Measurement - Experience after One Year of Operation
Hardware and infrastructural requirements to measure chromaticity in the LHC were available since the beginning. However, the calculation of the chromaticity was mostly made offline. This gap was closed in 2015 by the development of a dedicated application for the LHC control room, which takes the measured data and produces estimates for the chromaticity values immediately online and allows to ...
متن کاملATLAS Trigger and Data Acquisition: Capabilities and Commissioning
The ATLAS trigger system is based on three levels of event selection that selects the physics of interest from an initial bunch crossing rate of 40 MHz to an output rate of ∼200 Hz compatible with the offline computing power and storage capacity. During nominal LHC operations at a luminosity of 1034 cm−2s−1, decisions must be taken every 25 ns. The LHC is expected to begin operations with a pea...
متن کاملSimulation of Linear Beam Parameters to Minimize the Duration of the Squeeze at the Lhc
The betatron squeeze allows to increase the luminosity of a collider by reducing the β function at the interaction points. This operation has shown to be very critical in previous colliders. In this state of mind, the squeezing was performed extremely safely during the first year of operation of the Large Hadron Collider, at the expense of the duration of the process. As the turnaround time is ...
متن کامل