Considerations for the CDR and Strategy Update The current CDR planning focuses on 3 TeV and a downscaled not optimised 500 GeV machine, aiming for completion in the second half of this year: The power numbers are large, going well beyond the traditional CERN limits (that are not extremely well defined) for a 3 TeV machine An international review of the costs was originally planned for early April, which would put a lot of focus on the 3 TeV cost, and there is very little time to qualify costs or potential cost savings LHC results could influence our planning considerably: For example, the LHC physics reach, with 7-8 TeV, 1-3 fb-1, is in the range of TeV for squarks and gluinos and many different SUSY scenarios can be imagined and be (partly) within this reach – and other physics results might also provide valuable guidance in For the 2012 European Strategy Upgrade (probably by late Spring 2012 at the latest) we will need to bring forward a strategy for a LC that is in agreement with physics "known" at that time In addition we obviously need to present a project based on our technical studies and workable implementation scenarios: For example, if we need to scan from a minimum energy below 500 GeV all the way to 3 TeV, an intermediate energy step is probably needed To summarize, there are three issues: The timing of the CDR versus the Strategy input – they are so close that they need to connected (in time and content) LHC results might change/redefine the outlook sooner than expected a year ago It seems reasonable to study also an intermediate energy range between 0.5 and 3 TeV

Revised approach Suggested change of approach: Align the current LC activities at CERN with the LHC progress AND the European Strategy timescale right away. Present plans, costs and power for machine parameters that are in agreement and time with LHC physics results (and for key issues like cost only those to avoid confusion or wrong messages). Nevertheless keep the main CDR volumes on a reasonable timescale to get it completed but open up for a third intermediate energy. Present 3 TeV as reference because it is the hardest, 500 GeV and some intermediate energy range as well. This allows an exploration of technical and physics options and parameters as always advertised for the CDR.

Direct consequences Postpone the cost review in April to allow this approach to be adapted carefully (this is already done). Consider - working with the LPCC, and based on the main CDR volumes - a short document (replacing the executive summary) in time for the Strategy Update in 2012 (some time ahead of the Open Meeting = March 2012 at the latest). Avoid premature cost estimates in this volume, one approach is to consider only a 500 GeV machine for costing, and discuss cost drivers for higher energy options and the R&D needed to address these: Alternatively follow the advice in the ILC/CLIC combined working group to explore a range from 500 to 1000 GeV (cost band)

Conceptual Design Report 3 volumes: Vol 1: The CLIC accelerator and site facilities (H.Schmickler) CLIC concept with exploration over multi-TeV energy range up to 3 TeV Feasibility study of CLIC parameters optimized at 3 TeV (most demanding) Application to 500 GeV as first stage and intermediate energy range No cost figures (peer review postponed) Vol 2: The CLIC physics and detectors (L.Linssen) – timescales to be revisited, possibly some change needed Vol 3: CLIC study summary Comprehensive summary of vol 1 and 2 findings for European Strategy Staging scenario up to energy compatible with LHC Physics Including cost issues and cost drivers for R&D mitigation in next phase Proposing objectives and work plan of post CDR phase Schedule: Mid April 2011: Vol 1, Contributions by individual Authors mid July 2011: Vol 1, Reviewed for consistency by Editorial Board mid Sept 2011: Vol 1, Completed and Processed Dec 2011: Vol 1 and 2 SPC for comments March 2012: Vol 3 to European Strategy (vol 1 and 2 available as reference volumes)

CLIC Tentative Schedule Draft Conceptual Design Report(CDR) (Acc.&Det.) to SPC Final CLIC CDR and proposal next European Strategy European Strategy for Particle CERN Council Project Implementation Plan (PIP) and proposal for next phase

Before 2011 CDR (2011), CLIC feasibility established – Project Preparation phase Goal for 2016: Develop a project implementation plan for a Linear Collider (at CERN): 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 period to lay the grounds for full approval Considering the preparation steps foreseen and the resources situation it is clear that several key tasks will need further effort before the project can move into construction: ― finalization of the CLIC technical design, taking into account: ― results of technical studies done in the previous phase ― final energy staging scenario based on the LHC Physics results, which should be fully available by the time ― possible construction of CLIC Zero as first CLIC phase ― further industrialization and pre-series production of large series components with validation facilities ― further detector and physics studies, with increased emphasis on technical coordination issues and integration ― revision of the project implementation plan of CLIC, following the energy staging strategy and detailed resource discussion with all partners – providing the basis for a staged or full approval, and subsequent construction start up During this initial period we will need to produce the necessary documents to support a proposal for CLIC construction start-up Workplan for the coming years

The next steps – focusing points Define the scope, strategy and cost of the project implementation. Main input: The evolution of the physics findings at LHC and other relevant data Findings from the CDR and further studies, in particular concerning minimization of the technical risks, cost, power as well as the site implementation. A Governance Model as developed with partners. In order to achieve the overall goal for 2016 the follow four primary objectives for 2011—16 can defined: - to be addressed by activities (studies, working groups, task forces) or work-packages (technical developments, prototyping and tests of single components or larger systems at various places) Define and keep an up-to-date optimized overall baseline design that can achieve the scope within a reasonable schedule, budget and risk. Beyond beamline design, the energy and luminosity of the machine, key studies will address stability and alignment, timing and phasing, stray fields and dynamic vacuum including collective effects. Other studies will address failure modes and operation issues. Indentify and carry out system tests and programmes to address the key performance and operation goals and mitigate risks associated to the project implementation. The priorities are the measurements in: CTF3+, ATF and related to the CLIC Zero Injector System-tests related to verification of some of the issues mentioned under 2) needed.… still to be specified (technical work-packages and studies addressing system performance parameters) Develop the technical design basis. i.e. move toward a technical design for crucial items of the machine and detectors, the MD interface, and the site. Priorities are the modulators/klystrons, module/structure development including testing facilities, and site studies. (technical work-packages providing input and interacting with all points above)

“Resource – drivers” Very preliminary

Work-packages Mail sent Friday (from Roberto) with a first fairly comprehensive list of WPs for Keep in mind this is a first iteration, so there will be areas missing, and areas where we have to down-scale and optimize Several areas well suited for collaborating institutes and it is important to start defining responsibilities – in some case we have indicated possible groups to trigger discussion Follow up of the work: Revised annexes needed – do we need to revise the MoU ? Move towards WP follow up ahead of CBs (bi-yearly), outcome reported in the CBs - see talk of Herman later on More comprehensive project follow up every 6-8 weeks (going across the area mentioned earlier) Natural to spend some time on presenting the project organization in the CB in September

Ramp-up to about 30 MCHF in 2013 Total integrated  175 MCHF Assuming planned CERN contribution (MTP 2010 – about 105 MCHF)  need from collaborators 70 MCHF Material contributions from outside CERN should rise from 20-25% (present level) up to more than 1/3 Material budgets

Ramp-up from about 110 to 170 FTE Planned CERN contribution (MTP 2010) slightly decreasing! However, in the MTP after 2011/2012 most of non-staff manpower is not accounted for Taking this into account, the CERN manpower is substantially flat (however, a fraction of this will have to be provided by a material-to- personnel transfer)  need from collaborators up to ~ 50 additional FTEs Personnel Our programme for will be resource limited, and we hope that the discussions these three days can help us to define priorities