PETS Test Program for X-band Klystron Performance Evaluation

1. Test PETS Designs and Objectives I. Syratchev

2. PETS test program overview Test areas X-band klystron test stand at SLAC Two beam test stand CLEX, CERN Test beam line CLEX, CERN Access to the high power and full pulse length: 250 ns x 300 MW. High rep. rate. RF source driven. Access to the high power (~200 MW) Pulse length limited to 140 ns. Low rep. rate. Beam driven. The ultimate PETS high RF power performance RF power generation from the drive beam Demonstration of the ON/OFF capability Objectives Study/benchmarking of the beam dynamic in decelerator Testing of the special RF components Scaled (12->11.424) CLIC PETS. Active length 0.23m Two couplers. CLIC PETS. Active length 1.0m. Two couplers CLIC PETS. Active length 0.8m. One coupler PETS design specifics CIEMAT, Spain, autumn 2008. Origin and availability CERN, spring 2008. CERN, summer 2008. See details in S. Doebert dedicated talk PETS target is to generate reliably 136 MW x 250 ns RF pulses

3. X-band klystron test stand at SLAC SLAC (11.424 GHz) Access to the high power and full pulse length. With SLED II, 250ns x 300 MW were successfully delivered via single WR90 (S. Tantawi). Operation in a “waveguide mode”. Number of tests: #1. Scaled PETS/ no damping #2. Scaled PETS/ with damping #3. RF components

4. Two beam test stand, CLEX, CERN Integration layout for the phase I – PETS power production tests. CLEX 2BTS: Drive beam: 12GHz, 140ns, 30 A (max) CLIC PETS, active length 1.0 m, 135 MW will be produced with 20.8 A beam. Access to 270 MW (30 A) Number of tests: #1. PETS/ no damping material #2. PETS/ with damping material #3. PETS with recirculation (access to the full pulse length) #4. On/Off demonstration (slow)

5. Two beam test stand, CLEX, CERN

6. 12 GHz RF components Dry (stainless steel) RF load Directional coupler GYCOM, Russia RF and mechanical design, CERN Fabrication in CINEL, Italy 3-dB hybrid Attenuator/splitter RF and mechanical design, CERN Fabrication in CINEL, Italy Scaled from 30 GHz version. GYCOM Russia.

7. PETS with re-circulation DL 5A, 300 ns CR DBA 2BTS LPETS=1 m LWG = 1.8 m T =13.9ns η =0.82 P1 Power, MW P2 Time, ns In the CTF3 the PETS high power mode (high current) is limited in the pulse length by 140 ns. The re-circulation is a method to increase significantly power production and thus the drive beam current can be used directly from DBA (5A, 3GHz). In this case current pulse can be increased up to 300-400 ns. P2 P1 PETS with recirculation schematic: 0.96  0.85 0.96 RF pulse shapes P1 0.96 0.923 0.15 P2

8. PETS single bar RF quality control (in collaboration with CIEMAT, Spain) The waveguide cross-section is tuned to provide the similar parameters as in a complete PETS E-field H-field PETS bar + 2 side blocks WR90 Taper Test set-up schematic view probe Phase/period – 90 Frequency – 11.994 GHz Vg/C – 0.466 Mode ‘TE10’ side block PETS single bar

9. PETS assembly RF quality control (tested at 30 GHz ) S12, phase Phase Distance, mm S12, amplitude Distance, mm

10. Fast ON/OFF mechanical prototype study The electromagnet version developed in TS, CERN The objective is to demonstrate the fast – 20 ms and accurate movement (OFF) of the detuning wedges in a vacuum environment.