High power RF test of C-band rf mass-production components 8 GeV at XFEL/SPring-8

Tatsuyuki Sakurai1,A,B), Takahiro InagakiA,B), Chikara Kondo A,B), Katsutoshi ShirasawaA,B), Shinsuke SuzukiA),

Tsumoru ShintakeB) A) XFEL/JASRI

1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5148 B) XFEL/RIKEN

1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5148

Abstract

We report the high power rf test results of C-band accelerator system for X-ray free electron laser (XFEL) in SPring-8 site. In XFEL main accelerator, 64 C-band systems will be used in total, whose components have already finished mass production. We performed the high power RF test with three sets of the mass-produced components in XFEL test bunker. We operated the C-band components with the accelerating gradient, as high as 42 MV/m. We measured the high voltage breakdown rate and the dark current emission.

1 E-mail: t-sakura@spring8.or.jp

1 XFEL

!

XFEL

Proceedings of the 7th Annual Meeting of Particle Accelerator Society of Japan (August 4-6, 2010, Himeji, Japan)

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4 C-band

-354kV

4 RF

RF RFRF

RF 48MW

2.5 µsec RF

RF 2 µsecRF RF

RF 280 MW

Filling time(300 nsec)RF 3dB10

RF IQ5

XFEL35 MV/m

42 MV/m

5

1620 mm,

170 mm6

6

10

15

20

25

30

35

40

45

0 10 20 30 40 50

Accelerating Gradient of C-band

Acc

eler

atin

g G

radi

ent [

MV

/m]

Klystron output RF [MW]

��������������35 MV/m

42 MV/m

0

10

20

30

40

50

60

30 32 34 36 38 40 42

110 hours170 hours220 hours330 hours470 hours

Dar

k cu

rren

t em

issi

on [p

C/p

ulse

]

Accelerating gradient[MV/m]

Proceedings of the 7th Annual Meeting of Particle Accelerator Society of Japan (August 4-6, 2010, Himeji, Japan)

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60 Hz110 RF 2.5 µsec

40 MV/m 57 pC/pulse 350

470 40 MV/m 35 pC/pulseXFEL

300 pC/pulse C-band 64

3 GeV 8 GeV2

C-band

7200

50 70

36 MV/m

200 39 MV/m

40

35 MV/m

7 C-band

XFEL/SPring-8 RF

RFQ

2

97 kHz 18 RF

[10]RF

8

RF

8

9 8 RF

3029.7 1RF 8% XFEL 64

RF

9 RF

0

4

8

12

16

20

36 37 38 39 40 41

Fau

lt ra

te [C

ount

/day

]

Accelerating gradient [MV/m]

After 200hours

0

0.1

0.2

0.3

0.4

0.5

0.6

2000 2500 3000 3500 4000 4500 5000

Am

plitu

de [V

]

TIME[nsec]

0.5

0.52

0.54

0.56

4000 4050 4100 4150

180

185

190

195

200

28 28.5 29 29.5 30 30.5 31 31.5

SLE

D p

eak

RF

pow

er [M

W]

Tempurture on the SLED cavity surface [degree Celsius]

Proceedings of the 7th Annual Meeting of Particle Accelerator Society of Japan (August 4-6, 2010, Himeji, Japan)

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XFEL C3

42 MV/mXFEL 35 MV/m

500

201010 RF

XFEL

SES

[1]T.Shintake.et.al, “Status report on Japanese XFEL construction project at SPring-8”, IPAC10, 2010.

[2]T.Shintake et al, “The First Wakefield Test on the C-band Choke-mode accelerating structure.”, PAC’99, 1999.

[3] C

[4]T.Shintake et al, ”Development of C-band RF PulseCompressor System for the e+e- Linear Collider.”, PAC’97, 1997.

[5] C RF

[6]Y.Ohkubo et, al, “The C-band 50 MW Klystron usingTravelling-wave Output Structure”, LINAC’98, 1998.

[7]T.Shintake.et.al, “Compact klystronmodulator for XFEL/SPring-8”, IPAC10, 2010.

[8] XFEL/SPring-8RF

[9]T.Sakurai.et.al, “High power RF test on the mass-produced C-band RF components for XFEL/SPring-8”, IPAC10, 2010.

[10]T.Hasegawa.et.al, ”Status of a precise temperature-regulation system for the C-band accelerator at XFEL/SPring-8” , IPAC10, 2010.

Proceedings of the 7th Annual Meeting of Particle Accelerator Society of Japan (August 4-6, 2010, Himeji, Japan)

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