Status Report of the CLIC-ILC Joint WG on General Issues

1. Status Report of theCLIC-ILC Joint WG on General Issues Mike Harrison for the CLIC-ILC Joint WG* ILCSC Meeting, Mumbai 24th August 2011

2. Joint WG on « accelerator general issues » • Membership: • CLIC: Ph. Lebrun (co-chair), K. Peach, D. Schulte • ILC: E. Elsen, M. Harrison (co-chair), K. Yokoya • Mandate • The ILCSC and the CLIC Collaboration Board have approved formation of a CLIC/ILC General Issues working group with the following mandate: • Promoting the Linear Collider • Identifying synergies to enable the design concepts of ILC and CLIC to be prepared efficiently • Discussing detailed plans for the ILC and CLIC efforts, in order to identify common issues regarding siting, technical items and project planning. • Discussing issues that will be part of each project implementation plan • Identifying points of comparison between the two approaches to the linear collider • Reporting line • The conclusions of the working group will be reported to the ILCSC and CLIC Collaboration Board with a goal of producing a joint document.

3. Future topics for the WG • Issues part of project implementation plans • Siting • criteria and constraints • CLIC specificities • Preparation of technical procurement • Considerations of mass producing hi-tech components • QA, industrial follow-up • Decision point(s) for the LC • Points of comparison between the two approaches • Physics reach • Maximum energy: in relation to first LHC results • Energy staging and upgradeability • Luminosity (incl energy spread & background) & polarization • Lower-energy operation, energy fine scans • Accelerator technology • Explore (& compare ?) strength/weaknesses of the two approaches • Comparative reliability • Future technology development? • Cost & power estimates • Topical joint WGs • Follow-up of existing ones • Possible new topics: • RF power sources • Surface cleanliness in an industrial production • Beam instrumentation • Conclusions 2nd Interim Report Final Report 2nd Interim Report

4. An example of technical procurement lessons from the LHC A few of the conclusions from the LHC (Philippe LeBrun) Given that the GDE is presently focusing on exactly this topic for both cost and implementation reasons then this is timely information. “Don’t ask a vendor to do anything you do not know how to do yourself “ Philippe LeBrun

5. Considerations arising from ‘decision points’ A letter to the ILCSC: “In our view, there are two key timescales over the next three years, where the linear collider community in its broadest sense needs to form a coherent view of the next steps.” “The first is the update to the European Strategy for Particle Physics……. it is likely, we believe, to have a wider impact…………it is important that the international linear collider community produce a global assessment of the physics and the technology as input………….. it would be useful if the ILCSC could consider how best this might go forward.” “The second, and perhaps more important, issue will come in 2013, when the first run of the LHC is complete ………no new high-energy frontier data available for at least two and perhaps three years after that, ……. there will be a need for a full assessment of the prospects for the linear collider…… as a prelude to establishing, we hope, a linear collider project. This work could naturally be overseen by whatever structure replaces the ILCSC in 2013, but we feel that given the importance of this decision point it would be highly beneficial if the ILCSC started to consider how the community would best be organised to do this.” Given the timeline for the EU strategy we did not think this could wait for the next ILCSC meeting and the next committee report.

6. The Joint Working Groups There does not appear to be sufficient resources on the GDE side to consider expanding the number of the WG’s at this time. The TDR will require “all hands on deck” for the GDE. There are however topics where CLIC could benefit from additional resources. It is not clear at this point how the post-2012 landscape will evolve in respect to ILC related resources.

7. Points of Comparison between the two Approaches The General Issues WG has contacted the other WG’s prior to Granada to elicit input to help to “identify points of comparison between the two approaches to the linear collider.” The idea is not to engender any in-depth technical statements but rather a list of bullets This will allow the Joint WG to identify the issues they consider most relevant This allows for the possibility of discussion in Granada and is the first step towards addressing the final charge element