Performance of the LHC injector chain after the upgrade and potential development

TL;DR

The paper reviews the upgrades to CERN's injector complex aimed at doubling beam intensity and brightness for LHC and fixed target experiments, presenting expected performance and initial commissioning results.

Contribution

It provides a comprehensive overview of the LHC injector upgrades and their impact on beam performance for both collider and fixed target experiments.

Findings

Expected beam performance improvements post-upgrade

Initial results from 2021 beam commissioning

Potential access to new parameter ranges for fixed target beams

Abstract

The CERN accelerator complex prepares protons for the four big experiments at the Interaction Regions of the Large Hadron Collider (LHC) as well as for a number of fixed target experiments, which take beam directly from the LHC injectors. Between 2010 and 2021, a series of major changes were designed and implemented to the injector complex under the LHC Injectors Upgrade (LIU) project, with the main goal to enable the injector chain to produce LHC beams with doubled intensity and brightness. As a byproduct of these upgrades, the fixed target beams are also expected to benefit and possibly access parameter ranges previously unexplored. This letter summarises the main fixed target beams produced by the LHC injectors, their expected performance after the upgrade for the various beam types and shows first results from 2021 beam commissioning.