1. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 Technical Board Meeting TESLA Technology Collaboration Meeting Milano, February 28 th – March 3 rd, 2011

2. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 Charge for the Technical Board Members of the Tesla Technology Collaboration (TTC) According to the MoU of TTC the Technical Board TB shall provide advice to the Collaboration on technical activities towards reaching the goals of the Collaboration Mission. To this end, the TB will compile information on the technology activities in different technical areas, provide findings and recommendations to the CB. … The TB can be described as the technical arm of the Tesla Technology Collaboration, TTC. As such its primary duties are to carry forward the technical program of the TTC. Much of the work to the TTC is carried out in, and as a result of, the semi-annual meetings of the TTC. Working Groups focuse on technical items of current interest as defined by the CB. The TB will discuss and lay plans for advancing the issues under consideration. … Some activities of the TB and its members will be self-assigned while some will result from responses to requests from outside by leaders of the various projects which depend on superconducting RF.

3. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 TTC Technical Board Cavity: P. Kneisel (JLAB) L. Lilje (DESY) D. Reschke (DESY) K. Saito (KEK) R. Laxdal(TRIUMF) Coupler:E. Kako (KEK) W.D. Moeller (DESY) Module: N. Ohuchi(KEK) C. Pagani(INFN) B. Petersen (DESY) T. Peterson (FNAL) Linac and and Integration:H. Edwards(FNAL) M. Champion S. Michizono(KEK) new LLRF person needed! H. Weise (DESY) Chair Ex-Officio (per TTC MOU) Spokespersons of major test facilities TTF / FLASH: S. Schreiber ILCTA-NM (old SMTF): S. Nagaitsev STF: H. Hayano

4. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 TTC Technical Board Guests: Marc Ross(FNAL + ILC) Nobu Toge(KEK + ILC) Y. Yamazaki(J-PARC, KEK&JAEA) O. Napoly(CEA Saclay) J. Mammosser(JLAB) P. Pierini(INFN) W. Weingarten(CERN)

5. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 General studies Basically all topics brought up during the last TB were included in the agenda of this meeting. Pressure vessel certification. We wanted to hear information from all three regions. The topic became much more important with large series production. –At this meeting a complete session was included. –We heard about concepts how to deal with it –Next meeting we would like to hear about first results and experience with the relevant authorities. –Do we see a path towards an international approach? How can we contribute to international projects? Field emission: Calibration procedure for existing Vertical Test Stands, i.e. a calibration source. –Here we still see no progress. All are aware of this which but we still risk to compare apples with pears. –The TB members agreed forming a task force. The TB Chair will contact the lab representatives in the TB.

6. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 General studies Overview about existing Cavity Preparation Infrastructure. –Some talks were given at the present meeting. –But still: it would be nice to have an update of a information we collected in 2005. Since then two tables were established (KEK and within CARE, the EU funded projects). –We see a blooming of small R&D infrastructure – which is good. –But accelerator construction requires more general strategies. –In a somewhat lengthy discussion the TB members agreed on the goal: A two-step process should start first with a plane survey including all institutions, also universities. second (at the next meeting) to discuss strategies wrt. the beneficial use of distributed infrastructure. –TB charged a team: W. Weingarten, H. Hayano, J. Mammosser

7. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 General studies Which data can TTC expect from the larger scale cavity/coupler/module production of e.g. XFEL? –Here we had basically one talk. Further discussion could be useful. –Which systematic measurements could be added to the “simple” gradient and f.e. / Q check during module tests? Try to record processing events… –What can be done in the time given for the module test? –Can one define standards for module tests? –We expect a S1G summary at the next meeting. –Procedures for XFEL (and others?) should be available also. Comparison of cavity behavior for the first vs. the n-th power rise/cycle. Any news? –Let’s refer to the next SRF workshop. -More systematic simulations wrt. characterization of defects; review during next meeting? WP2 of this meeting addresses surface treatments and new procedures. -Again: see SRF workshop

8. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 General studies Power Coupler: discuss cleaning; also for the HOM coupler; –two talks at this meeting. Do we want more? –CW coupler for high beam power; who is working on it? –Include also HOM couplers and feedthroughs. –TB agreed to put more emphasis on this at next TTC meeting. Re-activate “old” topics (linac integration, LLRF, operation of srf linacs); system integration –The TTC Meeting’s program is quite full. –Including e.g. LLRF topics seems to be difficult (‘have their own meetings…’) –We could invite competent speakers for summaries thus re-creating the link between us cavity/module producers and the ‘operators’ of accelerator facilities New(?) Topic: sudden gradient degradation during cavity & module testing –We invite all TTC members to put more emphasis on the respective R&D –If results / finding become available before the next TTC meeting then use the TB to communicate your results. –Will come back to this topic in next TTC meeting’s agenda.

9. Hans Weise, DESY TTC Meeting, Milano, February 28 – March 3, 2011 Concluding discussion Two statements from the last TTC Meetings: Whenever projects arrive on the real axis some excellent R&D plans have to be stopped or paused. The TTC Meetings should be used to present the status of such activities with the hope that the baton can be passed to ‘some good friends’ in the SRF community. Do we see such topics? Please use coffee breaks, dinner chats … The TB would be happy to include more low beta cavity issues. As also discussed in the Collaboration Board the TB’s expertise should be strengthened as soon the relevant colleagues become regular participants of the TTC Meetings. Did we fail to integrate low beta community? Although no TB member was present, we see a good mixture. Quite some srf experts work on beta eq. 1 and low beta. Great!