2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

I. Syratchev

Test PETS Designs and Objectives

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

The ultimate PETS high RF power performance

RF power generation from the drive beam

Demonstration of the ON/OFF capability

Study/benchmarking of the beam dynamic in decelerator

X-band klystron test stand at SLAC

Two beam test standCLEX, CERN

Test beam lineCLEX, CERN

Testing of the special RFcomponents

Access to the high power and full pulse length: 250 ns x 300 MW. High rep. rate.RF source driven.

Ob

ject

ives

Test areas

Access to the high power (~200 MW) Pulse length limited to 140 ns. Low rep. rate.Beam driven.

PETS design specifics Scaled (12->11.424) CLIC PETS. Active length 0.23mTwo couplers.

CLIC PETS. Active length 1.0m. Two couplers

CLIC PETS. Active length 0.8m. One coupler

Origin and availability

CERN, spring 2008. CERN, summer 2008.

CIEMAT, Spain, autumn 2008.

PETS test program overview

See details in S. Doebertdedicated talk

PETS target is to generate reliably 136 MW x 250 ns RF pulses

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

Number of tests:#1. Scaled PETS/ no damping#2. Scaled PETS/ with damping #3. RF components

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”.

X-band klystron test stand at SLAC

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

Integration layout for the phase I – PETS power production tests.

Two beam test stand, CLEX, CERN

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)

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

Two beam test stand, CLEX, CERN

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

12 GHz RF components

Directional coupler

GYCOM, Russia

3-dB hybrid

RF and mechanical design, CERNFabrication in CINEL, Italy

RF and mechanical design, CERNFabrication in CINEL, Italy

Dry (stainless steel) RF load

Attenuator/splitter

Scaled from 30 GHz version. GYCOM Russia.

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

P1

0.9

6

0.96

0.96

0.923

PETS with re-circulation

5A, 300 ns

2BTS

DBA

CR

DL

T =13.9ns LPETS=1 mLWG = 1.8 m

η =0.82

0.85

0.15

PETS with recirculation schematic:

P2

0 100 200 3000

50

100

150

135

P1

P2

Time, ns

Pow

er, M

W

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.

RF pulse shapes

P2

P1

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

PETS single bar RF quality control (in collaboration with CIEMAT, Spain)

probeTest set-up schematic view

PETS single bar

side block

Phase/period – 90Frequency – 11.994 GHzVg/C – 0.466

Mode ‘TE10’

The waveguide cross-section is tuned to provide the similar parameters as in a complete PETS

E-field H-field

WR90Taper

PETS bar + 2 side blocks

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

0 50 100 150 200 250 3000

2

4

64.9

0

ami

273.270 si

0

30

60

90

120

150

180

210

240

270

300

330

6

4

2

0

7

3.11

ami

4.222

phhi

S12, amplitude

S12, phase

0 50 100 150 200 250 300200

100

0

100

200179.999

179.6

46

phi

ph1i

273.270 siDistance, mmPhase

Distance, mm

PETS assembly RF quality control (tested at 30 GHz )

2nd CLIC Advisory Committee (CLIC-ACE), CERN January 2008

Fast ON/OFF mechanical prototype study

The objective is to demonstrate the fast – 20 ms and accurate movement (OFF) of the detuning wedges in a vacuum environment.

The electromagnet version developed in TS, CERN