DESIGN OF ACCELERATING STRUCTURE TERMINATED WITH
KANTHAL-COATED COLLINEAR LOAD
Fusashi Miyahara #,A), Kazuyoshi SaitoB), Yoshio ArakidaA) , Kazuhisa KakiharaA) , Takuya KamitaniA) ,Hiroaki SakurabataC) ,Yasuo HigashiA), Shuji MatsumotoA) , Toshiyasu HigoA)
A)
High Energy Accelerator Research Organization (KEK)
1-1 Oho, Tsukuba, Ibaraki, 305-0801
B)
Hitachi, Ltd., Hitachi Research Laboratory
7-2-1 Omikacho, Hitachi, Ibaraki, 319-1221
C)
Hitachi, Ltd., Power Systems Company
3-1-1 Saiwaicho, Hitachi, Ibaraki, 317-8511

Abstract

We have been developing L-band accelerating structure with Kanthal-coated collinear load, consisting of 5 cells, forSuperKEKB. We have measured surface resistance of the Kanthal layers coated by various thermal spraying techniques.
We also evaluated the reduction of the resistance under high magnetic fields. Numerical simulation and theexperimental measurement show that the L-band accelerator structure can be designed with collinear load consisting ofKanthal-coated cells.

D q S n K m [ = p r Z Ŧ Ş Ì L-band « Ƣ Š ( Ǝ ƌ1.

SuperKEKB #)ne]MW> KEKB ( 40 (8x1035 [1/cm2/s];Ōĥ$" 7(1áÀ')BeVSqOÕƺį(ƺØƴƺØ`rfƇī87ƺØ`rf'Ʋ")Ē'ưŉ bCYDRrZ RF ƺØƭ;Ņ 7ƴƺØ`rf) 3.5 GeV10 nC (ƺØ`rf;SqIOWqĥ
Ŋ '  á   ŉ ń   ƴ ƺ Ø ; Flux concentrator
Ǆ FC ǅ [1]$Ro]?Z(æ 8Õ·ñ(«ƢŠ#ģý87ƴƺØĈŀQHMkq#Ĉ5 Tq
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ē¼(Ĉŀ¬Ł;ǃ7{$y«Ƣ¾ĮĎ#7S ^qZ( 5/11 (¾ĮĎ 1298.1818 MHz ( L ^qZ;ƨĄw¾ĮĎ(«ƢŠŰƱ# ( ŎOmVc;¥Ņ7{#TqaqImqI'á
87,^JVYÓ(LWl?Y(^qU;ā¦7{¸Ŵ$&7TqaqImqI( RF ^JVY 5Ó8LWl?Y^qU)čáū^VH
Il@qZ(´Ã$&7ĎMejorMkq#)ǆĜ( L-band «ƢŠ;Ņ '" S-band «ƢŠ$Ïº^VHIl@qZǆ'&7{¤" 7ŃÈ«ƢŠĜ$ 40 MW L-band____________________________________________#

fusashi.miyahara@kek.jp

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HFSS[12] ;Ņ MejorMkq;ž Dq SnķáƩ;³0 0.1mm $"Ʈ'à7Ɓŋąă  87 $ & 7 Ĥ ' Ĩ Ơ Ŗ Ł 2.5  ƺ ĩ  â Ł [1] L. Zang, et al., “Prototyping of the Flux Concentrator for
SuperKEKB Positron Capture”, Proceedings of the 9th
1.92x104 [S/m](ĽƗ;ŜųƁƼ'ƪůÆ 6 'Annual Meeting of Particle Accelerator Society of Japan,
ƚt(ƺÏ(í$ Ŏ;ŗprZƩ(MmqOsaka, Aug. 8-10, 2012.
Trñ) 2&/3 hrZ(¾ĮĎƥƙ¾ĮĎ'&7 [2] S. Matsumoto, et al., “High Power Test of L-BandĤ'Ɠď"6(ŧ0º:#-.dVUq
Accelerator Structure of SuperKEKB Injector Linac”,
Proceedings of the 9th Annual Meeting of Particle
I$8" 7{ŕƒ#ƺÏ(í)ƿAccelerator Society of Japan, Osaka, Aug. 8-10, 2012.
(ǆŜų)ơç(Qn( 8 ǌ 9 ©Řëó°(Ŝų#) 4 ©u#7tį(QnƩ'mVcn [3] S. S. Win, et al., “DEVELOPMENT OF THE NEW
C-BAND 50-MW ClASS SiC RF LOAD”, APAC2004,Ń8µáĮ(ÚÈ;ŗ" 7 VSWR )THP16001.
1.15 Řë#ƎƌƇī;Ķ" 6(//#2 [4] J. Watanabe, et al., ”DUCT-SHAPED SIC DUMMYLOAD OF LBAND POWER DISTRIBUTION SYSTEM
ǉŜų'DqSn;ķá8*ƴƺØńýQHMk
FOR XFEL/SPRING-8”, IPAC10, 2010, THPEA024.
q( L-band Km[=prZ$"¯¤&øŴ;Ć
!$¤ÜƵ')y'tį( 2 Qn [5] J. Haimson, Nucl. Instr. and Meth. 33 (1965), 93.
[6] Y. Arakida, et al., “Characteristics of Kanthal-Sprayed layer
ėuį(pOĻQn&%#(¾ĮĎUjr[qI
used for Collinear Load”, Proceedings of the 9th Annual#DqSnprZQnƩ+(ŪŌ#(µáĮ;Meeting of Particle Accelerator Society of Japan, Osaka,Aug. 8-10, 2012.
Ė'ÿİ$;Ģƍ" 7
[7] L. Lutz, private communication.
[8] Y. Sun, et al., “KANTHAL ALLOY BASED S-BAND
COLINEAR
LOAD
R&D
FOR
LINEARACCELERATORS”, IPAC10, TUPEA074.
[9] L. V. Pania, K. Mohri, “Magneto-impedance effect inamorphous wires”, Appl. Phys. Lett. 65 1189(1994).
[10] K. Saito, et al., “LOW-POWER TEST AND TUNING OF
L=BAND POSITRON CAPTURE ACCELERATINGSTRUCTURE”, TUPS1254, Proceedings of the 8th Annual
Meeting of Particle Accelerator Society of Japan, Tsukuba,Aug. 1-3, 2011.
[11] F. Miyahara, et al., “DEVELOPMENT OF L-BAND
POSITRON CAPTURE ACCELERATING STRUCTURE
WITH KANTHAL-COATED COLLINEAR LOAD FOR
SUPERKEKB”, IPAC12, 2012, TUPPR051.
[12] HFSS, http://www.ansys.com/

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