When I was a young postdoc, the only roadmaps I was familiar with were useful for planning vacations. In particle physics, we didn’t necessarily know where we were going but we still seemed to reach our goals with the vehicles to hand: PETRA at DESY, to discover the gluon, SppbarS (or SPS) at CERN, to discover the W and Z, LEP at CERN to put the Standard Model on firm footing, the Tevatron at Fermilab, to discover the top quark. I don’t remember if we had a roadmap when we were discussing the Large Hadron Collider (LHC) and the Superconducting Supercollider, but if we did, it surely included a linear electron-positron collider to complement the LHC and investigate the finer details of the hoped-for discoveries.
One thing is however certain: roadmaps like many things in life become outdated and eventually misleading and useless. The only way to avoid this is to update them when it is clear that the landscape has, or is about to, change significantly. In 2005, CERN Council reinvented its role, laid out in the CERN Convention, of leading European developments in particle physics that could go beyond CERN the laboratory in Geneva. After a year of deliberations in 2006, including an open meeting at LAL in Orsay for the community to express its views, the steering group produced a document that set out the European priorities. These were the delivery and exploitation of the LHC, R&D into accelerators, including the Compact Linear Collider (CLIC) Study, support of the ILC as the next likely machine for energy-frontier research and a variety of other measures. By agreement with the European Union, this document was incorporated into the European Strategy Forum for Research Infrastructures’ (ESFRI) own roadmap for large-scale facilities with a substantial European involvement. This opened up a variety of EU Framework 7 funding opportunities for the cornerstones of the CERN Roadmap, LHC, ILC and CLIC. For the ILC, we have received substantial R&D funding as well as support for investigations into governance for an ILC laboratory from the ILC-HiGrade project, which has just finished its funding. Other EU projects with ILC involvement enabled via the ESFRI roadmap include CRISP, which is in its early stages, and is designed to share best practice and information between a variety of so-called “preparatory phase” projects, such as the ILC.
CERN Council agreed that the European Roadmap should be reviewed and revised every five years. This review was thus put in train last year with a view to producing a new strategy early in 2013, which will then be formally adopted at a meeting in Brussels in May or June 2013. This is planned to coincide with a meeting involving European Research Ministers so that they can be exposed to the new strategy. A call for input both from individuals and interest groups has been issued by the CERN Council Strategy Secretariat, led by Tatsuya Nakada. These inputs should be available in advance of the Open Meeting to be held in Cracow from 10 to 13 September.
I, as European Director of the ILC Global Design Effort (GDE), Steinar Stapnes as Leader of the CERN Linear Collider Study and Juan Fuster as Chair of the European Committee for Future Accelerators (ECFA) Study for the Linear Collider, discussed how best to prepare an input to this process. The first thing we decided was that it made no sense to have a specifically European response on an issue which is of its very nature completely international; the input should be carefully coordinated with our colleagues from other regions. On the other hand, there are particular European issues and perspectives that ought to be reflected in a contribution to a European strategy. This led us to decide to set up a working group that contained experts from all three regions but had a preponderance of Europeans and a European chair.
The charge for the working group is as follows:
The committee is requested to review the physics case for a linear electron-positron collider in the centre-of-mass energy range from around 250 GeV – 3 TeV in the light of LHC results up to mid-2012 and building on previous studies.
The committee should consider the case for a linear collider in terms of the physics reach beyond that of the LHC under the assumptions in the current CERN planning: a) 300 fb-1 and b) 3000 fb-1.
It should assume linear collider performance based on the details contained in current documents from ILC and CLIC but without a detailed comparison of the relative performance of the machines. The aim is to make the strongest possible case for a generic linear collider for submission to the European Strategy process.
The committee is requested to submit its draft report to the GDE European Regional Director, the CERN Linear Collider Studies Leader and the Chair of the ECFA Study for the Linear Collider by June 18th 2012.
The final version of the report should be delivered by end July.
We were delighted that Francois Le Diberder, who is also a member of the ILCSC, agreed to chair the working group. In conjunction with him, we invited experts from across the world and were also delighted that we could convince so many to devote considerable time to preparing this input. The final composition of the working group is: Francois Le Diberder (Paris-VII University, LAL, Orsay) (chair); Jim Brau (University of Oregon); Rohini Godbole (Indian Institute of Science, Bangalore); Mark Thomson (University of Cambridge); Harry Weerts (Argonne National Laboratory); Georg Weiglein (DESY); James Wells (CERN) and Hitoshi Yamamoto (Tohoku University). They will work on updating our long-standing physics case for the linear collider in the light of the exciting results already beginning to emanate from the LHC.
The group has already had several meetings and welcomes input from colleagues at any stage. In order to facilitate this input and discuss the issues, the working group has organised an open meeting which will take place in Paris on 16 May. I would like to encourage you all to give the working group your views and if possible to attend this meeting, which is taking place at a time when the physics bedrock is moving under our feet as LHC results continue to flood in. This should guarantee an interesting discussion. It should be possible for most Europeans to fly in early on the morning of the 16th and catch the last flight back, should they feel able to resist the delights of a longer stay in Paris in the springtime.
Unfortunately I myself and other members of the GDE and Physics Directorates cannot attend as the only possible date that suited the working group clashes with the ILC Program Advisory Committee meeting in Fermilab. The working group will take some time to digest the results on the meeting and the other inputs from the community before producing the first draft of the report. This will be made available for comments from the community before it is input to the CERN strategy process. We hope that, having taken input from the community worldwide, this document will be helpful as the other regions update their own roadmaps. For example, the US is planning its own exercise, which will culminate in the traditional gathering in Snowmass in summer 2013.
Roadmaps are of course useless unless one has a vehicle to get to the destination. In the linear collider community, we are clear that we need two of these vehicles. One is the LHC, which is doing a great job in clarifying the highway we need to drive down. Often, however, the greatest points of interest can only be reached by following a signpost along a narrow track that can be very difficult to find. The ILC can explore such routes and ensure that we can reach the distant horizon from where we all expect that we will be able to see physics much more clearly than today.