# The Compact Linear Collider (CLIC) - Project Implementation Plan

## TL;DR

The CLIC project aims to build a high-energy linear collider with staged energies up to 3 TeV, utilizing advanced acceleration technology, to explore fundamental physics over a 25-30 year research program.

## Contribution

This document outlines the design, technological innovations, and implementation plan for the CLIC accelerator, including recent optimizations and cost estimates.

## Key findings

- Energy efficiency improved to around 170 MW for 380 GeV stage
- Cost estimate reduced to approximately 6 billion CHF
- Construction could start in 2026 with first beams by 2035

## Abstract

The Compact Linear Collider (CLIC) is a TeV-scale high-luminosity linear $e^+e^-$ collider under development by international collaborations hosted by CERN. This document provides an overview of the design, technology, and implementation aspects of the CLIC accelerator. For an optimal exploitation of its physics potential, CLIC is foreseen to be built and operated in stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3 TeV, for a site length ranging between 11 km and 50 km. CLIC uses a Two-Beam acceleration scheme, in which normal-conducting high-gradient 12 GHz accelerating structures are powered via a high-current Drive Beam. For the first stage, an alternative with X-band klystron powering is also considered. CLIC accelerator optimisation, technical developments, and system tests have resulted insignificant progress in recent years. Moreover, this has led to an increased energy efficiency and reduced power consumption of around 170 MW for the 380 GeV stage, together with a reduced cost estimate of approximately 6 billion CHF. The construction of the first CLIC energy stage could start as early as 2026 and first beams would be available by 2035, marking the beginning of a physics programme spanning 25-30 years and providing excellent sensitivity to Beyond Standard Model physics, through direct searches and via a broad set of precision measurements of Standard Model processes, particularly in the Higgs and top-quark sectors.