1. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Working Group Linac techology introduction Cryomodule design and Assy. Tuner issue. Danilo Barni Danilo.Barni@mi.infn.it

2. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Cryostat Design Issue Actual design - III Generation: –3 module delivered and assemblied, 2 almost installed –12m long 8 9-cell cavities 1 Superconducting QUAD –Compatible with movable(+- 20mm) or quasi-fixed coupler(+-2mm) by sliding supports (easy allignements) –Lateral 4.2K QUAD (Begin/End of the module) –ALL drawing for cryostat available in AutoCAD on EDMS –There is no real “specification book” for industry production

3. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Cryomodule Assembly and operation Experience pointed out during the assembly of existing modules (3 generations and other specific system) –Long time between assembly and test of modules => no feedback possible on assembly procedure M1* tested after more than 2 years M4 will be tested after 2 years – Module assembly in steps because people involved in the assembly also involved in other high- priority program (HERA) M3 M4 –Performance of module 1* and 3 worse than expected after vertical and horizontal tests – results not yet reprocidible. –Leaks in all modules (except of Superstructure-module) mainly in RF-feedthrought and ceramics but also in the 2K vessel. –Couplers and coupler assembly often with serious problems. –adjustment of HOM couplers not satisfactory: problem of communication between rf and clean-room stuff (WDM);

4. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Cryomodule Assembly and operation Open questions,necessary improvements –TEST of module #4 and #5 to check improvements and new technological solution. –Review of specifications of all components + materials –Vessel Classification of modules: pressure vessel regulations; safety issues; Demagnetisation of vacuum vessel necessary? –Cold Mass Number and type of necessary sensors Tubing distances to allow use of orbital welding Alignment/survey: more confortable, more overview Tolerable cool-down/warm-up speed –String Tuner (which one / Piezos) BPM: cleanroom compatible + better performance He-Tank: problems with flanged bottom 2K feed line? Problems with introduction of vibrations? Specification of cables (especially rf- cables) Magnetic shielding: no information about exact effectiveness, compatibility with tuner –Cryomodule Mechanical vibrations Transportation procedure Review of vacuum design –Comparsion of cost of components: different supplier--- Book of specifications

5. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Cryomodule Design Issue We need to improve and review really many things Everything has to be included and fit in the cryomodule… for example –2K QUAD –Central QUAD –New tuner with Piezos –Coupler –Heat sink of components (cone, posts, diagnostic) –Evrerything that will be discussed in this WG. INTEGRATION We need a good and reliable way to exchange and approve drawing coming from different labs and industries. Definition of procedure for drawing and design approve. Definition of CAD packages end visualization tool to check clereance and interaction regions Intensive use of EDMS

6. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Tuner design and specs At present 2 family of tuner exists: Lateral Tuner (so called Saclay tuner) –Lot and lot and lot of experience (since 1997), in TTF-I Chechia but most of this experience can be moved to other tuner design –Piezos has been implemented and full tested at room temperature and 2K –All the R&D program at DESY on Piezos is carried on Saclay Tuner BUT –Longitudinal space consuming –Too soft for passive Lorentz compensation Coaxial Tuner –1st prototype never really tested –Blade tuner. Cold tested on superstructure module In principle stiff enough for passive lorentz compensation. Piezo compatibility just on paper-work but never tested Compatibility with 3rd generation module never tested –New DESY coaxial Tuner Easier to integrate with 3rd generation cryomodule

7. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Tuner Review and R&D need Which TUNER ??? –Parallel study VS Converge on one solution: When the decision ? –To answer we need real specification on clearance, stiffness, tuning range… Integration of Piezo actuator is a MUST. It has to be proven for the chosen Tuner. – Cold Test at least on Chechia. –Most of the work done on Saclay tuner optimisation and components (Motor, harmonic driver, ball bearing treatment, control system) can be used to design Coaxial tuner. Compatibility with the Magnetic Shielding at industry level

8. TESLA MEETING 26-28 May 2003 Frascati LINAC TECHNOLOGY WORKING GROUP Additional Information Leaks in tests - Detlef Reschke Flange designs - Kirsten Zapfe Cleanroom Quality control - Axel Matheisen Coupler Design and Processing - Terry Garvey / W.-D. Moeller HOM and Pickup - Wolf-Dietrich Moeller Experience Module Assembly Rolf Lange Active tuning - Lutz Lilje/Stefan Simrock