1. 1 Albrecht Wagner, EPS Aachen, 19 July 2003 Road Map for High Energy Physics The DESY View The strategy for the DESY programme is based on three elements: Accelerators, particle physics, research with photons Current Projects: HERA DORIS VUV-FEL Planned Projects: TESLA X-FEL TESLA Linear Collider Upgrade Project: PETRA SR Focus in this talk on particle physics aspects

2. 2 Albrecht Wagner, EPS Aachen, 19 July 2003 2000-2002 substantial modifications of HERA + HERA experiments Goal for HERA II: H1 und ZEUS 1000 pb -1 (e + p + e - p) with polarised e + /e - and improved detectors HERMES first measurements of „transversal“ spin structure of proton and analysis of nucleon structure in terms of „Skewed Parton Distributions“ HERA-B (until 2003) production b-Quarks in p-N, production of charmonium-states and their propagation in nuclear matter HERA II

3. 3 Albrecht Wagner, EPS Aachen, 19 July 2003 e + polarisation -> 50 % für H1/ZEUS/HERMES HERA II Luminosity Goal: 7 10 31 cm -1 s -1 by - stronger focussing - increase in beam current (background!) Reached in 2003 (with reduced # bunches) ~ 3 10 31 (HERA I-nominal 1,5 10 31 ) High background has created delay of 1 year Efficiency of operation Still needs improvements

4. 4 Albrecht Wagner, EPS Aachen, 19 July 2003 Status of HERA The background and operational issues of HERA have been largely solved However, the background is still a concern Shut down is ~ finished –start up with p,e in early August. –luminosity run in 2003: October – December the HERA experiments are in a good shape and eager for (more) data taking goal for integrated luminosity of 1 fb-1 until end of 2006 (scheduled end of HERA II) -> challenging Recent proposal for a HERA III programme ->

5. 5 Albrecht Wagner, EPS Aachen, 19 July 2003 Measure the behavior of inclusive, diffractive and exclusive reactions in the region near Q 2 =1 GeV 2 to understand parton to hadron transition. Measure F L over widest possible kinematic range, as this is a crucial observable for testing our understanding of radiation processes in QCD. Measure exclusive processes (VM production, DVCS) over wide W range to precisely pin down energy dependence of cross section. Need t-dependence of cross sections to get 3-D map of proton. Measure forward jet cross sections over widest possible rapidity range, to study radiation processes over the full rapidity range from the proton to the scattered quark. AND, do it all with nuclei ! Open Questions in QCD – HERA III

6. 6 Albrecht Wagner, EPS Aachen, 19 July 2003 measurements would provide a significant step in the understanding of the strong hadronic interactions. agrees that many of the proposed measurements cannot be done at other existing or foreseen facilities. present level of the theoretical understanding of QCD does not allow predictions of the proposed measurements at the level of the precision achievable by the experiments. The PRC/ESC rate the HERAIII program at lower priority compared to the Linear Collider programme. Given the other priorities of DESY and its resources, PRC and ESC do not recommend the continuation of HERA III PRC, ESC Recommendation

7. 7 Albrecht Wagner, EPS Aachen, 19 July 2003 Transformation of PETRA Today PETRA is the injector for HERA e, p. Transformation into a 3rd generation SR light source: reconstruct 1/8 of arc German government has agreed to fund PETRA III Transformation scheduled to start in 2007

8. 8 Albrecht Wagner, EPS Aachen, 19 July 2003 TESLA Linear Collider and X-ray Laser Daresbury, 23 –25 September 2002 TESLA LC and X-FEL are based on SC RF technology The linac designs are essentially identical X-FEL now a stand-alone facility

9. 9 Albrecht Wagner, EPS Aachen, 19 July 2003 The Scientific Case A world-wide consensus has formed for a baseline LC project in which positrons collide with electrons at energies up to 500 GeV, with luminosity above 10 34 cm -2 s -1. The energy should be upgradable to about 1 TeV. The LHC and LC will offer mutually supporting views of the new physics world at the TeV scale. OECD GSF Consultative Group on High-Energy Physics: There should be a significant period of concurrent running of the LHC and the LC, requiring the LC to start operating before 2015. ‚Consensus document‘ http://sbhep1.physics.sunysb.edu/~grannis/wwlc_report.html

10. 10 Albrecht Wagner, EPS Aachen, 19 July 2003 The Status of SC Cavities SC RF structures for accelerators were developed in many countries To meet the challenge of high gradients needed for high energy Linear Colliders the TESLA collaboration has attracted ~ all the world expertise in SC, thus leading to major progress

11. 11 Albrecht Wagner, EPS Aachen, 19 July 2003 The TESLA Collaboration The TESLA Collaboration: - at present 51 Institutes in 12 countries and still growing

12. 12 Albrecht Wagner, EPS Aachen, 19 July 2003 International TRC Quotes: Results from International Technical Review (Feb. 2003)

13. 13 Albrecht Wagner, EPS Aachen, 19 July 2003 Progress on TESLA Technology First high power test of an electro-polished cavity Completely new final preparation sequence (no etching after tank welding) very good result, similar to vertical test Continuing the R&D is one of the top priorities Due to the XFEL DESY and partners will focus in the preparation of collider on linac related issues (industrialisation, reliability, high gradient programme)

14. 14 Albrecht Wagner, EPS Aachen, 19 July 2003 High Power Test of a complete EP nine-cell cavity 1/8th of a TESLA cryomodule 5 Hz, 500  s fill, 800  s flat-top 33- >35 MV/m with no interruption related to cavity- coupler-klystron for more than 600 hours No field emission HERA plantCalib.Measurement Power/kW Eacc/MV/m

15. 15 Albrecht Wagner, EPS Aachen, 19 July 2003 TESLA Energy Strategy Assuming that cavities will reach 35 MV/m: TDR (March 2001) Base line design for 500 GeV, upgrade possibility outlined initially operate at an energy of about 500 GeV, to explore the Higgs and related phenomena, and then increasing the energy to 800-1,000 GeV, to more fully explore the TeV energy scale.

16. 16 Albrecht Wagner, EPS Aachen, 19 July 2003 Experience with TTF Proof of principle and first FEL-experiments at TTF I laser driven electron gun photon beam diagnostics undulator bunch compressor superconducting accelerator modules pre- accelerator e - beam diagnostics

17. 17 Albrecht Wagner, EPS Aachen, 19 July 2003 VUV-FEL User Facility at TTF II RF commissioning in 2003, start of FEL operation in 2004 TTF 1 TTF 2 experimental hall 250 MeV 1 GeV

18. 18 Albrecht Wagner, EPS Aachen, 19 July 2003 Recommendations concerning TESLA The Science Council requests the Federal Government to give its binding consent to German participation in the LC as soon as possible after the project proposal has been submitted with specific details concerning international funding and international cooperation. The Science Council requests the Federal Government to give its binding consent to German participation in the TESLA X-FEL project as soon as possible after the revised project proposal has been submitted. The German Science Council has issued in November 2002 its recommendations: DESY submitted answers to these requests

19. 19 Albrecht Wagner, EPS Aachen, 19 July 2003 Government Decision The decisions of the German Ministry for Education and Research concerning TESLA was published on 5 February 2003: DESY in Hamburg will receive the X-FEL as European Project Germany is prepared to carry half of the 673 MEuro investment cost. Today no German site for the TESLA linear collider will be put forward. This decision is connected to plans to operate this project within a world-wide collaboration DESY will continue its research work on TESLA in the existing international framework, to facilitate German participation in a future global project

20. 20 Albrecht Wagner, EPS Aachen, 19 July 2003 Next Steps Linear Collider Continuation of the high gradient programme (construction, optimisation and tests of cavities with 35 MV/m) Build-up of a European LC Design Teams as part of an international Design Team Participation in the LC working groups of ICFA and ECFA X-FEL Continuation of the R&D work for the X-FEL accelerator Formation of a planning group with all interested partners (including future users) Analysis of the present concept for the linear accelerator, as described in the TDR supplement, and the laser facility by the planning group Adaptation of the project parameters to include the findings and recommendations of the planning group

21. 21 Albrecht Wagner, EPS Aachen, 19 July 2003 Next Steps for the X-FEL Site and some of the technical parameters for XFEL Laboratory are currently reconsidered. Formation of European Working Groups under way. Aim for decision on construction in 2005!

22. 22 Albrecht Wagner, EPS Aachen, 19 July 2003 Consequences of the Decision for the Linear Collider Given the decision of the German government the community will now take a path used for other international projects (e.g. ITER): unite first behind one project with all its aspects, including the technology choice, in 2004 and then approach all possible governments in parallel in order to trigger the decision process, definition of structure of organisation and site selection Aim at approval of LC around 2006/2007 The ILCSG agrees that it would be highly desirable to form a Core Group to begin the international design, based on accumulated work to date, but reexamined in a completely international context.

23. 23 Albrecht Wagner, EPS Aachen, 19 July 2003 Technology Decision How: Gather a committee of wise persons, who use criteria to be developed by the ILCSC, to recommend a technology choice to the ILCSC. The regional steering committees will each nominate 4 persons from which the ILCSC will choose three from each list for a total of 9 wise persons. First discussion of the make-up of the committee in August. Advice in this will be widely sought from the community. Aim at joint selection of one technology in 1 year.

24. 24 Albrecht Wagner, EPS Aachen, 19 July 2003 Collaboration of interested accelerator laboratories and institutes world-wide with the goal to build, operate and utilise large new accelerators Follows example of major detector collaboration in particle physics Partners contribute through components or subsystems Facility would be the common property of the participating countries, these would also share the responsibility and cost for operation. Project of limited duration (25 years) A new model of international cooperation How to Realise Big Accelerator Projects? Global Accelerator Network

25. 25 Albrecht Wagner, EPS Aachen, 19 July 2003 Strategy for Particle Physics at DESY Present Programme: HERA II, astroparticle physics (Amanda/Icecube), theory HERA will end 2006/2007 For DESY the LC is the top priority after LHC, in accordance with the world wide agreed recommendations Discussion of strategy for research in particle physics at DESY in the time between HERA end and LC has started: Strategy group has been set up in spring 2003 (DESY and users, members of advisory committees) Similar groups exist at SLAC, FNAL, KEK