1 Tunnel implementations (laser straight) Central Injector complex

CLIC energy scans (for a single stage) Requirement from physics : vary the c.m. energy for a given CLIC machine. Main options : Early extraction lines : significant hardware modifications needed Reduce gradient : disadvantage: need to scale down bunch charge linearly with gradient for stability, leading to a significant luminosity loss (green) CLIC drive beam scheme: gradient can be reduced while increasing pulse length. A large fraction of the luminosity loss is recovered (black). Modifications to drive beam generation are minimal. Lower gradient can be achieved by switching of phase of incoming drive beam bunches : Drive beam energy after extraction

There are limits to the CLIC performance (luminosity) during an energy scan

What is the physics ? - some production cross-sections - One of many possible models for new physics SM physics, for example top studies should not be forgotten Or whatever your favorite model is …

CMSSM Likelihoods for sparticle thresholds Preliminary

CLIC energy staging 3 TeV Stage Linac 1Linac 2 InjectorComplex I.P. 3 km 20.8 km 3 km 48.2 km Linac 1Linac 2 InjectorComplex I.P. 7.0 km 1 TeV Stage 0.5 TeV Stage Linac 1Linac 2 InjectorComplex I.P. 4 km ~14 km 4 km ~20 km CLIC two-beam scheme compatible with energy staging to provide the optimal machine for a large energy range Lower energy machine can run most of the time during the construction of the next stage. Physics results will determine the energies of the stages. Optimization need to take into many account many others parameters: performance and luminosities at various energies, costs, construction and commissioning times, manufacturing/re-use/move of components, etc CHANGE MIDDLE BOX TO SHOW RANFE 1-2 TEV The drive beam setups can deal with various stages of the machine

Slide about initial stage Start at 250 GeV with transfer line, expand to 400 GeV …

CLIC implementation questions Many questions: Waiting for physics guidance: Current trend are increasing limits on squark/gluino masses (but loop holes exist) – and currently no information about other SUSY particles (can be much lighter in some models) or Higgs (Standard Model or several) – Any wiser after summer conferences ? – Benefits of running close to thresholds versus at highest energy, and distribution of luminosities as function of energy – We assume that we have to be sensitive from a light Higgs threshold (~200 GeV) to multi-TeV, in several stages What are the integrated luminosities needed and what it is the flexibility needed within a stage – Interested in looking in more detail for at least one model in order to make sure the machine implementation plan can cope with whatever will be needed – Complementarity with LHC a key What are reasonable commissioning and luminosity ramp up times ? – LHC will need 3 years to get to 50 fb -1 and collects ~50 fb-1/year at (roughly) How would we in practice do the tunneling and productions/installation of parts in a multistage approach – Cheapest (overall) to do in one go but we don’t know final energy needed, and it is likely that we can make significant technical process before we get to stage 3 (or even 2?) – Timescales for getting into operation, and getting from one stage to another Answers are possible but must be found based on all available information at the time the project is launched

– Goal: Develop a project implementation plan for a Linear Collider : Addressing the key physics goals as emerging from the LHC data With a well-defined scope (i.e. technical implementation and operation model, energy and luminosity), cost and schedule With a solid technical basis for the key elements of the machine and detector Including the necessary preparation for siting the machine at CERN Within a project governance structure as defined with international partners After 2016 – Project Implementation phase: Including an initial project to lay the grounds for full construction (CLIC 0 – a significant part of the drive beam facility) Finalization of the CLIC technical design, taking into accoun the results of technical studies done in the previous phase, and final energy staging scenario based on the LHC Physics results, which should be fully available by the time Further industrialization and pre-series production of large series components with validation facilities CLIC next phases (add more about , and beyond) Final CLIC CDR and feasibility established European Strategy for Particle CERN Council