1. ● Offer the reliable system to the Asian regional facility STF. ● Improve TTF design and demonstrate in the beam line for RDR / TDR. ● Establish industrial design and make the precise cost estimation in close cooperation with industries. Purpose of STF Baseline Cavity Development

2. Baseline Cavity Unit Input Coupler Port Piezo Stack Slide Jack Drive Shaft Titanium Jacket Support Base Invar Rod 2K He Line Motor Outside Piezo Replacement OK

3. DESY Cavity Support System is weak.

4. Stiff Jacket Baseplate (Ti) Thick Titanium Baseplate No Stiffener 2.8 t 3.5 t Thick Beam Pipe Magnetic Shield

5. ＳＴＦ Ｂａｓｅｌｉｎｅ Ｃ ａｖｉｔｙ

6. Three STF-Baseline Cavities The #4 Cavity will be delivered in the end of April. The vertical tests for 4 cavities will be carried out till the end of July.

7. Results of 1 st Vertical Test (4. high field) X-rays Radiation Level Eacc,max = 19.1 MV/m, Limited by Field Emission The 2nd vertical test will be carried out after additional surface removal by EP.

8. Ｉｎｐｕｔ Ｃｏｕｐｌｅｒ ｆｏｒ Ｂａｓｅｌｉｎｅ Ｃａｖｉｔｙ Improved input coupler design for simplicity & reduced cost (no tuning) 5K cooling here 80K cooling here Beam pipe Warm window Door-knob conversion Cold window Vacuum port TRISTAN Type Coaxial Disk Ceramic Static Loss 5 W Dynamic Loss 3 W Static Loss 1.1 W Dynamic Loss 0.2 W Qext = 2.0 x 10 6 Prf = 350 kW

9. Components for High Power Test Stand Input CouplersDoorknobs Coupling Waveguides

10. Ｔｕｎｅｒ ａｎｄ Ｊａｃｋ ｅｔ Guide slider Pulse motor (outside) Piezo element Slide Jack Motor drive shaft (G10) Titanium Jacket 2K He line Support base Invar Rod

11. Slide Jack Tuner Piezo Stack Drive Shaft Taper Invar Rod Roller

13. Input Coupler Warm Window Vacuum Port Cold Window 80K 5K Beam Pipe Monitor Port Low loss 0.2W to 5K Higher Static loss 1.2W to 5K No Tuning