PRODUCTION STATUS OF ACCELERATOR COMPONENTS

N. Shigeoka, M. Kimura, S. Miura, K. Okihira Mitsubishi Heavy Industries, Ltd. (MHI)

Mihara, Hiroshima, 729-0393, Japan

Introductions

Mitsubishi Heavy Industries (MHI) has started manufacturing of accelerator components such as accelerating structures in 1960s. For example, in a field of normal conducting accelerator, in recent years, MHI had handled mass production of C-band choke-mode accelerating structures and SLED for Riken SACLA, production of DTL, SDTL (Separated DTL), ACS (Annular Coupled Structure) for JAEA/KEK J-PARC. In latest years, MHI manufactured over 120 S-band accelerating structures for PAL-XFEL and shipment has completed in March 2015. In addition, MHI has accepted order of C-band waveguide network prototype (CWNP) for SwissFEL project in June 2014 and has been already delivered to PSI in December 2014. MHI also has been accepted order of 26 C-band waveguide network series (CWNS) and the production of them is in progress now.

C-band waveguide network for SwissFEL One waveguide network provides RF power from one klystron to four accelerating structure. Six directional couplers for RF monitor, three RF splitters and nine vacuum ports are included in one unit.In order to precisely fit to input flange of each accelerator structure, dimension accuracy between four interface flanges are 0.2 mm CWNP had been already installed in the test facility and high power test of the CWNP by PSI is planned. Production of CWNS (approximately 500 waveguides) has been started. First 4 units of the CWNS have been already delivered to PSI in

August 2015.

S-band accelerating structures for PAL-XFEL Mass-production of the S-band 3 m long accelerating structure started in June 2012 and finished at March 2015. Totally 120

structures has been delivered to PAL. Results of LLRF measurement after tuning shows excellent performance of production.

Appearance of the structure Frequency 2856 MHzAccelerating Type C.G.Phase Shift per Cavity 2π/3Unloaded Q 13000Attenuation Constant 0.56Input / Output VSWR < 1.05Phase error < 2.5 degreeNumber of Cells 82 + 2 Coupler CellsFilling Time 0.84 μsLength 3 mCoupler Type Quasi-symmetrical type

Main parameters

Schematic of H-plane splitter

Result of LLRF measurement

0

0.5

1

1.5

2

2.5

1

1.01

1.02

1.03

1.04

1.05

1.06

1.07

#000 #020 #040 #060 #080 #100 #120

Cum

ulat

ive

phas

e er

ror [

deg]

VSW

R

Production number

Input VSWROutput VSWRCumulative phase error

Symmetry error of splitters

0

0.5

1

1.5

2

2.5

3

3.5

00.010.020.030.040.050.060.070.080.09

0.1

Sym

met

ry e

rror

(pha

se) [

degr

ee]

Sym

met

ry e

rror

(am

plitu

de) [

dB]

Component

Symmetry error (amplitude) [dB]

Symmetry error (phase) [degree]

threshold of symmetry error (phase)

threshold of symmetry error (amplitude)

CWNP CWNS

Residual gas analysis (RGA)

1 10 20 30 40 50 60 70 80 90 100Mass [amu]

2.2E-10

1.8E-10

1.4E-10

1.0E-10

6.0E-11

2.0E-11

Cur

rent

[A]

H2+ H2O+

N2+

CO2+

Overview of the waveguide network (series production for LINAC 1

~6.1 m

~7.2 m

Dimension accuracy: 0.2mm

Horizontal waveguide

Vertical waveguide

Outgassing rate measurement

2.0E-08

4.0E-08

6.0E-08

8.0E-08

1.0E-07

Vertical(CWNP)

Horizontal 1(CWNP)

Horizontal 2(CWNP)

1st shipment(CWNS)

Out

gass

ing

rate

[Pa

m3 /(

sm

2 )]

Waveguide

threshold of outgassing rate

Main parameters Bandwidth 5712 ± 20 MHzPeak power 320 MW*Average power 15 kWPulse repetition rate 1-100 HzVSWR < 1.04Operating pressure < 1x10-6 PaWaveguide size WR187Flange type C-band A-DESY

Coupling of the RF monitor-60 ± 2 dB(5712 ± 3 MHz)

Directivity of the RF monitor> 25 dB(5712 ± 20 MHz)

RF symmetry error of splitters< 0.1 dB in amplitude< 3° in phase

RF leak to vacuum manifold < -85 dB

Residual gas analysis(RGA)

The RGA spectrum must showno evidence of hydro carbonsand the peaks > 40 Amu(excluding peak 44) should be

0.1%Outgassing rate < 1.0 10-7 Pa m3/( s m2 )*Maximum power in between the pulse compressor and the 1st splitter

WEP038

Schematic of RF monitor

Definition:Coupling: S31 (-60 2 dB) Directivity: S31 - S32 (> 25 dB)

20

25

30

35

40

45

50

55

60

-62

-61.5

-61

-60.5

-60

-59.5

-59

-58.5

-58

0 5 10 15 20 25 30 35

Dir

ectiv

ity [d

B]

Cou

plin

g [d

B]

Monitor No.

Coupling [dB]

Directivity [dB]

threshold of directivity

permissible range of coupling

CWNP CWNS

Coupling and directivity of RF monitors