AWAKE is a proton-driven plasma wakefield acceleration experiment. We show that the experimental setup briefly described here is ready for systematic study of the seeded self-modulation of the 400 GeV proton bunch in the 10 m-long rubidium plasma with density adjustable from 1 to 10×10 14 cm −3 . We show that the short laser pulse used for ionization of the rubidium vapor propagates all the way along the column, suggesting full ionization of the vapor. We show that ionization occurs along the proton bunch, at the laser time and that the plasma that follows affects the proton bunch.

The LHC collimation system will require simultaneous management by the LHC control system of more than 500 jaw positioning mechanisms in order to ensure the required beam cleaning and machine protection performance in all machine phases, from injection at 450 GeV to collision at 7 TeV. Each jaw positionis a critical parameter for the machine safety. In this paper, the architecture of the LHC collimator controls is presented. The basic design to face the accurate control of the LHC collimators and the interfaces to the other components of LHC Software Application and control infrastructures are described. The full controls system has been tested in a real accelerator environment in the CERN SPS during beam tests with a full scale collimator prototype. The results and the lessons learned are presented. The LHC collimation system will require simultaneous management by the LHC control system of more than 500 jaw positioning mechanisms in order to ensure the required beam cleaning and machine protection performance in all machine phases, from injection at 450 GeV to collision at 7 TeV. Each jaw positionis a critical parameter for the machine safety. In this paper, the architecture of the LHC collimator controls is presented. The basic design to face the accurate control of the LHC collimators and the interfaces to the other components of LHC Software Application and control infrastructures are described. The full controls system has been tested in a real accelerator environment in the CERN SPS during beam tests with a full scale collimator prototype. The results and the lessons learned are presented. Large Hadron Collider Project

EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH CERN -AB Department

No abstract

A rotatable-jaw collimator design was conceived as a solution to recover from catastrophic beam impacts which would damage a collimator at the Large Hadron Collider (LHC) or its High-Luminosity upgrade (HL-LHC). One such rotatable collimator prototype was designed and built at SLAC and delivered to CERN for tests with LHC-type circulating beams in the Super Proton Synchrotron (SPS). This was followed by destructive tests at the dedicated High Radiation to Materials (HiRadMat) facility to validate the design and rotation functionality. An overview of the collimator design, together with results from tests without and with beam are presented.