#, A), A), A)
Masashi Kimura #, A), Nobuyuki ShigeokaA), Sadao MiuraA), A) Mitsubishi Heavy Industries, Ltd.
Abstract A free electron laser facility, SwissFEL, is under construction to aim at routine operation in 2017 by Paul Scherrer
Institut (PSI). Mitsubishi Heavy Industries (MHI) has accepted order of one C-band waveguide network prototype (CWNP) for SwissFEL project in June 2014 and has been already delivered to PSI in December 2014. A C-band waveguide network connects the klystron to the four inputs of the accelerating structures. The CWNP has already installed in the test facility and high power test of it is planned by PSI. MHI also has accepted order of 26 C-band network series (CWNS) and the production of them have been started. We report the properties and the low-level RF test results for the CWNP.
1. Paul Scherrer Institut (PSI)
2017 SwissFEL [1] 2014 6 SwissFEL C 1 ( 21 ) PSI 12 26 ( 494 ) 2014 11
SwissFEL C LLRF
2. SwissFEL C
SwissFEL C 1
Figure 1 1 RF
[2] (vertical waveguide) 4 RF (horizontal waveguide) RF RF (Table 1) ±0.2 mm Table 2 SwissFEL C
~6.1 m
~7.2 m
Pulse compressor
Figure 1: Overview of the waveguide network (series production for LINAC 1). Table 1: Components Shape of the Waveguide Network (series production)
Components shape
Bending sections
(sweep type)
Bidirectional couplers
# masashi2_kimura@mhi.co.jp
Proceedings of the 12th Annual Meeting of Particle Accelerator Society of Japan August 5-7, 2015, Tsuruga, Japan
PASJ2015 WEP062
VSWR < 1.04
Waveguide size WR187
-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
(RGA)
The RGA spectrum must show no evidence of hydrocarbons and the peaks > 40 Amu (excluding peak 44) should be 0.1%
Outgassing rate < 1.0×10 Pam3/(sm2)
*Maximum power in between the pulse compressor and the 1st splitter
3.
3 ANSYS HFSS 15.0 RF

PSI
RF (VSWRRF )



E
RF
RF
4.1 VSWR
21 VSWR 21 VSWR < 1.04 ( 1.016)
4.2 RF
1 6 RF Figure 3 RF RF port 1 port 2 port 3 port 4 port 1 port 3 RF S31port 2 port 3 RF S32 (coupling) S31(directivity) S31-S32 Figure 4 RF (@5712 MHz) VSWR < 1.02
Figure 3: Schematic of RF monitor.
Definition: Coupling: S31 (-60 ± 2 dB) Directivity: S31-S32 (>25 dB)
Proceedings of the 12th Annual Meeting of Particle Accelerator Society of Japan August 5-7, 2015, Tsuruga, Japan
PASJ2015 WEP062
Di re
ct iv
ity [d
permissible range of coupling
4.3 RF
1 E 1 H 2 Figure 5 H RF port1RF 1 port 2RF 2 port 3 port 2 RF ω2port 3 RF ω3 RF |S21-S31|RF |ω2-ω3|Figure 6 E H RF (@5712 MHz)(|S21- S31| < 0.1 dB|ω2-ω3| < 3°)
Figure 5: Schematic of H-plane splitter.
0
0.5
1
1.5
2
2.5
3
3.5
Sy m
m et
ry e
rr or
(p ha
Figure 6: Symmetry error of splitters.
5.



1 10 20 30 40 50 60 70 80 90 100 Mass [amu]
Cu rr
en t [
Figure 7: Residual gas analysis of the vertical waveguide. Figure 8
(horizontal waveguide)
O ut
ga ss
in g
ra te
[P a
m 3 /

(port1)
(port2)
(port3)
Proceedings of the 12th Annual Meeting of Particle Accelerator Society of Japan August 5-7, 2015, Tsuruga, Japan
PASJ2015 WEP062
PSI
(Figure 10)

26
( 494 )
Figure 10: Horizontal waveguide installed in the PSI test facility.
[1] F. Loehl et al., “Status of the SwissFEL C-band Linac”, in
Proceedings of 36th International Free Electron Conf., Basel, 2014, 322.
[2] R. Zennaro et al., “C-band RF pulse compressor for SwissFEL, “ in Proc. Of the IPAC 2013 Conf., Shanghai, China,. 2013, pp. 2827-2829.
Proceedings of the 12th Annual Meeting of Particle Accelerator Society of Japan August 5-7, 2015, Tsuruga, Japan
PASJ2015 WEP062