1. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Work on PETS Developed at CIEMAT Laura Sánchez on behalf of Accelerator Technology Group, CIEMAT

2. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. PETS in CLIC CLIC module. Source www.clic-study.web.cern.ch PETS are structures to transfer power developed for the future linear collider CLIC. Its function is to extract power from the drive beam and transfer it to the main beam. RF POWER PARTICLES The particles interact with the corrugated structure converting the beam kinetic energy into electromagnetic energy. The RF power flows through the structure and is collected at the end by a power extractor and carried through rectangular waveguides. PETS concept

3. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Demonstrate the feasibility of the two beam scheme CIEMAT work on PETS Outline: TBL PETS prototype. TBL PETS series production. Double length CLIC PETS (CLEX module). General Scheme of CTF3 CTF3 CLIC Test Facility 3 Ciemat has been working in PETS since 2007

4. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS CIEMAT contribution First prototype: Engineering design. Fabrication and assembly. Low power RF Test. Test Beam Line in CTF3. Study and validate the drive beam stability during deceleration. Length TBL PETS = 4 CLIC PETS Scheduled 16 PETS (TBL with 12 PETS in 2012) Series production: Implementation of modifications. Assembly of 3 PETS. Low power RF test. Fabrication of several parts for 8 tanks + 4 tanks more

5. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS: First prototype ENGINEERING DESIGN 8 copper rods clamped by screws and aligned by dowel pins. Steel ring: compensation of rod sag. Power extractor: 3 brazed parts. 2 WR90 waveguides. Waveguides and flanges joined by brazing Cooling pipes. ∆T water ~ 3ºC. Pipes and connectors joined by brazing Stainless steel vacuum tank. Ports and bellows TIG welded. CF flanges First prototype scheme

6. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS : First prototype 800 mm OFE Cu Tight tolerances ± 20 μm Ra < 0.4 μm High speed milling Copper rods 2 Stress relieve HT 1 h 180ºC Vertical error corrected by the steel ring Longitudinal error Most cells under tolerances. Some out of tolerances Diamond tools Machining at Utillajes Huerta (Spain)

7. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS : First prototype Coupler 3 Cu OFE parts Courtesy of Serge Mathot Filler alloy (%wt)Filler melting range (ºC)Brazing temp (ºC)Vacuum (mbar) 68.5 Ag/26.5 Cu/5Pd807-810823<10 -5 Vacuum brazing Alignment ± 10 μm No filler overflow Brazing parameters at CERN Several failed tests at AIMEN. Brazing for the first prototype at CERN Machining after brazing Brazed parts Ensuring the power reflection efficiency by the choke

8. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS : First prototype Waveguides X-band Flange CF 63 Flange OFE Cu Flange WR90 Filler alloy (%wt)Filler melting point (ºC)Brazing temp (ºC)Vacumm (mbar) 82Au/18 Ni950980<10 -5 Vacuum brazing No filler overflow No leaks Final brazing parameters at AIMEN Several tests at AIMEN. Courtesy of J Sotelo

9. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS : First prototype Cooling pipes Filler alloy (%wt)Filler melting point (ºC)Brazing temp (ºC)Vacuum (mbar) 72Ag/28Cu780800<10 -5 Vacuum brazing Brazing parameters at AIMEN No leaks Courtesy of J Sotelo Cu/SS joint SS Ni plated ¼”  OFE Cu SS connector Pipe bending

10. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS : First prototype Assembly Vertical position Positioning of the Cu rods on top of the end support and coupler Checking the distance between opposite external sides of the rods Nominal: 113.00 mm Measured: 112.99 mm Clamping the cooling pipes and temperature sensors (PT-100) Tank assembly Waveguides assembly Leak testing. Leak rate < 10 -10 mbar·l/s

11. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. A special test bench was designed to check the shape accuracy by RF measurements on each rod. Two side blocks put together with a single PETS bar to create inside a mode with same properties as the decelerating mode. Results agree with 3-D mechanical measurements, but it is not being used due to the risk of scratching on the rod side faces. TBL PETS : First prototype RF low power tests (I) SINGLE ROD TEST BENCH POWER EXTRACTOR TEST BENCH At 12 GHz: S 11 = - 40dB (reflection) S 21 = - 3 dB (transmission) S 31 = - 3 dB (transmission) Results in agreement with the simulations

12. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. RF low power tests (II) TBL PETS : First prototype PETS TEST BENCH S parameters S 11 = -16 dB (Reflection) S 41 = -36 dB (Transmission to port 4) S 21 =S 31 = -3.8 dB (Extraction) Measurements with an antenna, measuring the electric field through the slots between the rods. Phase shift measurements for different frequencies 40 MHz detuning Is not the real detuning, since PETS must be synchronized with a relativistic electron beam PETS dispersion curve and speed of light line 50 MHz detuning In the worst case, only a 10% loss of extracted power.

13. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Implemented modifications in the design: Copper assembly supports Cooling pipe connectors and flexibility Dowel pins for positioning of copper rods A unique steel flange for waveguides RF absorber plates of SiC. TBL PETS. Series Production.

14. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS. Series Production. Fabrication and brazing of cooling pipes and waveguides for 7 PETS + 4 PETS (end of 2011). Assembly of 3 PETS and low power RF characterization of power extractor and PETS (S- parameters and measurements with the antenna). SiC plates. Absorbers are necessary to damp the high order modes. Exhaustive market survey was carried out. After testing several samples at CERN SiC EKASiC-F by ESK. S parameters of the extractor of the 3rd PETS Contribution to the series production

15. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. TBL PETS PETS commissioning status FIRST CIEMAT PETS SECOND CIEMAT PETS THIRD CIEMAT PETS FOURTH CIEMAT PETS SERIES PRODUCTION PROTOTYPE Installed in TBL and decelerating 14 A and 19 A beams Received by CERN in week 36 Sent to CERN in week 38 Courtesy of Steffen Doebert

16. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Double length CLIC PETS PETS designed by CERN to generate RF power in CLEX MODULE. Based on 11.4GHz PETS tested at SLAC. Compact design: Compact coupler Power extraction Waveguides Cooling circuit Vacuum mini-tank. Supported by VII FP (EuCARD) CIEMAT CONTRIBUTION Engineering design. Fabrication and assembly. Low power RF Tests.

17. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. ENGINEERING DESIGN Eight rods of OFE Cu with SiC plates fixed by Al supports. Copper rods joined by EBW. Two couplers to allow power recirculation. Cu OFE compact coupler with a double choke and RF and vacuum flanges. Brazing in two steps. Mini tank of SS. Joined by TIG welding to an additional SS ring brazed to the coupler. Double length CLIC PETS

18. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Double length CLIC PETS 80 regular cells 532 mm long OFE Cu rod Tight tolerances ± 15 μm Ra < 0.4 μm High speed milling Copper rods 2 Stress relieve HT 1 h 180ºC Dimensional control of the first copper rod SiC plates 8 SiC pieces per Cu rod EkaSiC-F Joint of the copper rods Firing treatment: 1000 ºC /10 -5 mbar/ 1h Electron beam welding (EBW) at CERN High power of the beam produces: Narrow weld Little distortion of the base material Machining at DMP (Spain)

19. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Double length CLIC PETS Compact couplers Double choke to reflect the power with a bandwidth broader than that in single choke. Two output waveguides in one, with a T-junction. Cooling circuit. Cooling capacity about 100 W coming from the RF and beam losses. X-band RF flanges (male and female) Vacuum flanges: Female coupler: CF 63 Male coupler: Quick CF flange Tolerances: Beam hole ± 10 μm Choke ± 15 μm Waveguides ± 20 μm RF surface Ra < 0.3 μm One half of the coupler High speed milling 2 Stress relieve HT 1 h 180ºC Cu OFE parts High precision diamond monocrystal tools Machining at DMP (Spain)

20. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Brazing Step Tipe of jointsFiller alloy (%wt) Filler melting range (ºC) Vacuum (mbar) First Cu/Cu Cu/SS (unplated) 58Ag/32Cu/10Pd824-852 <10 -6 SecondCu/SS (unplated)68.5 Ag/26.5 Cu/5Pd807-810<10 -6 Vacuum brazing Brazing for the first prototype at ECOR (Italy). In progress… Joint of the compact couplers Machining of the X-band flange insertion Alignment by dowel pins Double length CLIC PETS Ni plating on SS not necessary due to the high vacuum Joints: Half extractor/half extractor (Cu/Cu) Extractor/Double choke (Cu/Cu) Double choke/ Vacuum flange (Cu/SS) Extractor/Connectors cooling circuit (Cu/SS) Extractor/Additional rig for welding to the vacuum tank (Cu/SS) Extractor (waveguide) / X-band Flange (Cu/SS) First brazing Second brazing

21. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Assembly Double length CLIC PETS Orbital TIG welding Length of the vacuum tank has been adjusted for guaranteeing the electric contact of the rods and the couplers. Joint Couplers/Bars by mechanical contact, supported by the outer vacuum tank Vacuum ports made by pulling out the tank wall Rounded edges are better to achieve ultra high vacuum Machining and welding at Trinos Vacuum Projects (Spain)

22. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Scheduled RF measurements Double length CLIC PETS COUPLER S 11 AND S 12 MEASUREMENTS Three different rings: Lo (70 mm) Lo +60 º (74.169mm) Lo+120º (78.337mm) EIGTH RODS WITH DAMPING MATERIAL Before EBW. Rods only. Measurement of S 11 and S 12. Measurements of the phase shift values with electronic probe held by a digital ruler (similar to TBL PETS). After EBW. Rods + couplers. Measurement of S 11 and S 12. Bead pull measurements (optional).

23. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Finally to conclude… CIEMAT has been collaborating with CERN on the PETS development since 2007. First step was the engineering design, fabrication and RF tests of a PETS tank for the TBL experiment. The fabrication of the long copper rods (800 mm) with tight tolerances was specially challenging. After successful installation of two prototypes at TBL line and carried out the deceleration measurements at 14 A and 19 A, the third and fourth PETS has been sent to CERN. Finally, the fabrication of a double length CLIC PETS is ongoing, which will be part of the Test Module to demonstrate the two beam acceleration concept. In this case, a new compact coupler design is implemented, with a mini-tank for vacuum tightness.

24. Work on PETS Developed at CIEMAT. L. Sánchez ICWS11. 26-30 September 2011. Thank you for your attention.