01 Electron Accelerators and Applications
1A Electron Linac Projects

Paper	Title	Page
SUPB001	Analyzing Surface Roughness Dependence of Linear RF Losses	1
	C. Xu, M.J. Kelley The College of William and Mary, Williamsburg, USA C.E. Reece JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Topographic structure on Superconductivity Radio Frequency (SRF) surfaces can contribute additional cavity RF losses describable in terms of surface RF reflectivity and absorption indices of wave scattering theory. At isotropic homogeneous extent, Power Spectrum Density (PSD) of roughness is introduced and quantifies the random surface topographic structure. PSD obtained from different surface treatments of niobium, such as Buffered Chemical Polishing (BCP), Electropolishing (EP), Nano-Mechanical Polishing (NMP) and Barrel Centrifugal Polishing (CBP) are compared. A perturbation model is utilized to calculate the additional rough surface RF losses based on PSD statistical analysis. This model will not consider that superconductor becomes normal conducting at fields higher than transition field. One can calculate the RF power dissipation ratio between rough surface and ideal smooth surface within this field range from linear loss mechanisms.
MOPLB01	Emittance Control for Different FACET Beam Setups in the SLAC Linac	138
	F.-J. Decker, W.S. Colocho, N. Lipkowitz, Y. Nosochkov, J. Sheppard, H. Smith, Y. Sun, M.-H. Wang, G.R. White, U. Wienands, M. Woodley, G. Yocky SLAC, Menlo Park, California, USA
	Funding: Work supported by U.S. Department of Energy, Contract DE-AC02-76SF00515. The linac beam at SLAC requires different setups for different users at FACET (Facility for Advanced aCcelerator Experimental Tests) area, like highly compressed, intense bunches, or lower charge, long bunches. These require typically a lengthy tuning effort since with a energy-time correlation ("chirp") bunch transverse wakefield kicks can be compensated with dispersive trajectory oscillations and vice versa. Lowering the charge or changing the bunch length will destroy this delicate balance. Besides the typical steering to minimize BPMs (Beam Position Monitors) with correctors, we applied different techniques to try to localize beam disturbances like dispersion with phase changes, RF-kicks and RF quadrupole fields turning a klystron off and on, or varying the phase, and finally wakefield kicks with different beam intensities. It is also important to quantify BPM to quadrupole offsets with "bow-tie" plot and that the correctors give the expected kicks with orbit response matrix measurements.
	Slides MOPLB01 [0.826 MB]
MOPLB02	Positron Injector Linac Upgrade for SuperKEKB	141
	T. Kamitani, M. Akemoto, D.A. Arakawa, Y. Arakida, A. Enomoto, S. Fukuda, K. Furukawa, Y. Higashi, T. Higo, H. Honma, N. Iida, M. Ikeda, E. Kadokura, K. Kakihara, H. Katagiri, M. Kurashina, S. Matsumoto, T. Matsumoto, H. Matsushita, S. Michizono, K. Mikawa, T. Miura, F. Miyahara, T. Mori, H. Nakajima, K. Nakao, T. Natsui, Y. Ogawa, S. Ohsawa, M. Satoh, T. Shidara, A. Shirakawa, H. Sugimoto, T. Suwada, T. Takatomi, T. Takenaka, Y. Yano, K. Yokoyama, M. Yoshida, L. Zang, X. Zhou KEK, Ibaraki, Japan D. Satoh TIT, Tokyo, Japan
	The KEKB B-factory is under an upgrade construction for the SuperKEKB. To achieve 40 times higher luminosity, the linac is required to inject electrons and positrons with higher intensities (e-: 1 nC → 5 nC, e+: 1 nC → 4 nC) and lower emittances (e-: 300 → 20 μm, e+: 2100 → 10 μm). This paper describes the upgrade scheme of the positron source. A new positron capture section will have larger transverse and energy acceptances by introducing a flux concentrator and large aperture L-band and S-band accelerating structures. Beam line layout and quadrupole focusing system will be rearranged for the enlarged beam acceptance. Beam optics is designed to be compatible for positron and electron beams with different energies and emittances. Pulsed quadrupoles and steering magnets are added for better flexibility in optics and orbit tuning. Parameter optimization of the positron source by optics calculation and particle tracking simulation is described.
	Slides MOPLB02 [0.575 MB]
MOPB001	Emittance Control for Different FACET Beam Setups in the SLAC Linac	174
	F.-J. Decker, W.S. Colocho, N. Lipkowitz, Y. Nosochkov, J. Sheppard, H. Smith, Y. Sun, M.-H. Wang, G.R. White, U. Wienands, M. Woodley, G. Yocky SLAC, Menlo Park, California, USA
	Funding: Work supported by U.S. Department of Energy, Contract DE-AC02-76SF00515. The linac beam at SLAC requires different setups for different users at FACET (Facility for Advanced aCcelerator Experimental Tests) area, like highly compressed, intense bunches, or lower charge, long bunches. These require typically a lengthy tuning effort since with a energy-time correlation ("chirp") bunch transverse wakefield kicks can be compensated with dispersive trajectory oscillations and vice versa. Lowering the charge or changing the bunch length will destroy this delicate balance. Besides the typical steering to minimize BPMs (Beam Position Monitors) with correctors, we applied different techniques to try to localize beam disturbances like dispersion with phase changes, RF-kicks and RF quadrupole fields turning a klystron off and on, or varying the phase, and finally wakefield kicks with different beam intensities. It is also important to quantify BPM to quadrupole offsets with "bow-tie" plot and that the correctors give the expected kicks with orbit response matrix measurements.
MOPB002	Positron Injector Linac Upgrade for SuperKEKB	177
	T. Kamitani, M. Akemoto, D.A. Arakawa, Y. Arakida, A. Enomoto, S. Fukuda, K. Furukawa, Y. Higashi, T. Higo, H. Honma, N. Iida, M. Ikeda, E. Kadokura, K. Kakihara, H. Katagiri, M. Kurashina, S. Matsumoto, T. Matsumoto, H. Matsushita, S. Michizono, K. Mikawa, T. Miura, F. Miyahara, T. Mori, K. Nakao, T. Natsui, Y. Ogawa, S. Ohsawa, T. Shidara, A. Shirakawa, H. Sugimoto, T. Suwada, T. Takatomi, T. Takenaka, Y. Yano, K. Yokoyama, M. Yoshida, L. Zang, X. Zhou KEK, Ibaraki, Japan D. Satoh TIT, Tokyo, Japan
	The KEKB B-factory is under an upgrade construction for the SuperKEKB. To achieve 40 times higher luminosity, the linac is required to inject electrons and positrons with higher intensities (e-: 1 nC → 5 nC, e+: 1 nC → 4 nC) and lower emittances (e-: 300 → 20 μm, e+: 2100 → 10 μm). This paper describes the upgrade scheme of the positron source. A new positron capture section will have larger transverse and energy acceptances by introducing a flux concentrator and large aperture L-band and S-band accelerating structures. Beam line layout and quadrupole focusing system will be rearranged for the enlarged beam acceptance. Beam optics is designed to be compatible for positron and electron beams with different energies and emittances. Pulsed quadrupoles and steering magnets are added for better flexibility in optics and orbit tuning. Parameter optimization of the positron source by optics calculation and particle tracking simulation is described.
MOPB003	Recent Improvements to the Control of the CTF3 High-Current Drive Beam	180
	B. Constance, R. Corsini, D. Gamba, P. Skowroński CERN, Geneva, Switzerland
	In order to demonstrate the feasibility of the CLIC multi-TeV linear collider option, the drive beam complex at the CLIC Test Facility (CTF3) at CERN is providing high-current electron pulses for a number of related experiments. By means of a system of electron pulse compression and bunch frequency multiplication, a fully loaded, 120 MeV linac is used to generate 140 ns electron pulses of around 30 Amperes. Subsequent deceleration of this high-current drive beam demonstrates principles behind the CLIC acceleration scheme, and produces 12 GHz RF power for experimental purposes. As the facility has progressed toward routine operation, a number of studies aimed at improving the drive beam performance have been carried out. Additional feedbacks, automated steering programs, and improved control of optics and dispersion have contributed to a more stable, reproducible drive beam with consequent benefits for the experiments.
MOPB004	Design and Operation of a Compact 1 MeV X-band Linac	183
	G. Burt, T.N. Abram, P.K. Ambattu, C. Lingwood Cockcroft Institute, Lancaster University, Lancaster, United Kingdom I. Burrows, T. Hartnett, J.P. Hindley, C.J. White STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom P.A. Corlett, A.R. Goulden, P.A. McIntosh, K.J. Middleman, Y.M. Saveliev, R.J. Smith STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	A compact 1 MeV linac has been produced at the Cockcroft Institute using X-band RF technology. The linac is powered by a high power X-band magnetron and has a 17 keV 200 mA thermionic gun with a focus electrode for pulsing. A bi-periodic structure with on-axis coupling is used to minimise the radial size of the linac and to reduce the surface electric fields.
MOPB005	High Gradient Operation of 8 GeV C-Band Accelerator in SACLA	186
	T. Inagaki, C. Kondo, Y. Otake, T. Sakurai RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
	SACLA (SPring-8 angstrom compact free electron laser) is the X-ray free electron laser (XFEL) facility. In order to shorten the 8 GeV accelerator length, a C-band (5712 MHz) accelerator was employed. Since the accelerating gradient of C-band accelerating structure is 35 MV/m in nominal, the active accelerator length is 230 m. In total, 64 klystrons, 64 pulse compressors, and 128 accelerating structures are used. In order to withstand the high surface field (~ 100 MV/m), and to reduce the amount of dark current, which decreases the demagnetization effect of undulators, the accelerating structures are carefully fabricated in the factory.　After high power RF conditioning of 500 hours, the beam commissioning was started in February 2011. For night time of the commissioning, we continued the RF conditioning. The RF breakdown rate of the structure was steadily decreased. Now we operate the accelerator with the beam energy as much as 8.3 GeV, and the accelerating gradient of 37 MV/m in average. We found the amount of dark current is small enough. So far no trouble occurred in C-band RF components of 64 sets.
MOPB007	Study of Microbunching Instabilitity in the Linac of the Shanghai Soft X-Ray Free Electron Laser Facility	189
	D. Huang, Q. Gu, M. Zhang SINAP, Shanghai, People's Republic of China
	The microbunching instability in the LINAC of a FEL facility has always been an issue which may degrade the quality of the electron beam. As the result, the whole facility may not be working properly. Shanghai soft X-ray FEL project (SXFEL), which is planned to start construction by the end of 2012, will be the first X-ray FEL facility in China. In this article, detailed study will be given based on the physical design of the facility to gain better understanding and control over the possible microbunching instability in SXFEL, which is critical to the success of the project. Moreover, the contribution of the possible plasma effects to the instability will also be studied by modifying the physical model of the longitudinal space charge (LSC) impedance.
MOPB011	Photoinjector of the EBTF/CLARA Facility at Daresbury	192
	B.L. Militsyn, D. Angal-Kalinin, C. Hill, S.P. Jamison, J.K. Jones, J.W. McKenzie, K.J. Middleman, B.J.A. Shepherd, R.J. Smith, R. Valizadeh, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom N. Bliss, M.D. Roper STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
	A description is given of a photoinjector designed for Compact Linear Advanced Research Accelerator (CLARA) and Electron Beam Test Facility (EBTF), which will eventually be used to drive a compact FEL. The photoinjector is based on a 2.5 cell S-band photocathode RF gun operating with a copper photocathode and driven by a third harmonic of Ti: Sapphire laser (266 nm) installed in dedicated thermally stabilized room. The injector will be operated with laser pulses with an energy of up to 2 mJ, a pulse duration of 100 fs and initially a repetition rate of 10 Hz, with the aim of increasing this eventually to 400 Hz. At a field gradient of 100 MV/m provided by a 10 MW klystron the gun is expected to deliver beam pulses with energy of up to 6 MeV. Duration and emittance of electron bunches essentially depend on the bunch charge and vary from 0.1 ps at 20 pC to 5 ps at 200 pC and from 0.2 to 2 mm mrad respectively. Additional compression of the electron bunches will be provided with a velocity bunching scheme. For thermal stability the low energy part of the injector is mounted on an artificial granite support.
MOPB012	First RF Measurement Results for the European XFEL SC Cavity Production	195
	A.A. Sulimov, P.B. Borowiec, V. Gubarev, J. Iversen, D. Kostin, G. Kreps, K. Krzysik, A. Matheisen, W.-D. Möller, D. Reschke, W. Singer DESY, Hamburg, Germany
	The first reference cavities (RCV) for the European XFEL Project are being tested within the collaboration of Research Instruments (RI), E. ZANON, IFJ-PAN and DESY: - production and warm RF measurements of cavities and their components at RI and ZANON; - surface preparation at DESY; - cold RF tests at DESY by IFJ-PAN. Purpose of the RCV is to establish a stable cavity fabrication and qualification of the surface preparation infrastructure at industry. All necessary RF measurements were done, starting with mechanical fabrication in 2011, till the tuning and cold cavity RF tests in 2012. We present the first results of RF measurements within RCV production for the European XFEL.
	Poster MOPB012 [1.843 MB]
MOPB013	Experimental Results on the PHIL Photo-injector Test Stand at LAL	198
	R. Roux, F. Blot, J. Brossard, C. Bruni, S. Cavalier, J-N. Cayla, V. Chaumat, M. El Khaldi, A. Gonnin, P. Lepercq, E.N. Mandag, B. Mercier, H. Monard, C. Prevost, V. Soskov, A. Variola LAL, Orsay, France
	Since the first beam in November 2009 of the alphaX S-band RF gun, upgrades of the beamline have been carried out. Several YAG screens based transverse dimensions monitors have been installed as well as supplementary charge diagnostics. We will present a detailed experimental characterization of the RF gun performances such as emittance measurement using a solenoid scan and energy spread as a function of the RF phase. Most of the accelerator operation and experimental results have been carried out with a copper photo-cathode. PHIL being a test stand for photo-injectors, we have also tested a magnesium photo-cathode with the aim of higher charge per bunch thanks to its higher quantum efficiency. We will report on the results of this experiment. In May 2012, a new RF gun, the PHIN gun, will be installed. This gun which is also a S-band 2,5 cells is a copy of the one that LAL built for the CLIC Test Facility 3 at CERN. In the future, we plan to use this gun to produce a high charge up to 10nC with CsTe photo-cathodes introduced in the gun from a UHV transfer chamber. Preliminary tests and measurements of the beam produced by this gun with a copper photo-cathode will be presented.
MOPB014	Electron Model of a Dogbone RLA with Multi-Pass Arcs	201
	S.A. Bogacz, G.A. Krafft, V.S. Morozov, Y. Roblin JLAB, Newport News, Virginia, USA K.B. Beard Muons. Inc., USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Supported in part by USDOE STTR Grant DE-FG02-08ER86351 The design of a dogbone RLA with linear-field multi-pass arcs was earlier developed for accelerating muons in a Neutrino Factory and a Muon Collider. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over separate-arc or pulsed-arc designs. Such an RLA may have applications going beyond muon acceleration. This paper describes a possible straightforward test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme, in which a 4.35 MeV/c electron beam is injected in the middle of a 2.9 MeV/pass linac with two double-pass return arcs and is accelerated to 17.4 MeV/c in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to a readily available 1.5 GHz. The footprint of a complete RLA fits in a 25x7 m area. The scheme utilizes only fixed field magnets for both injection and extraction. The hardware requirements are not very demanding making it straightforward to implement the scaled design using available equipment.
MOPB016	In-situ Measurement of Beam-induced Fields in the S-band Accelerating Structures of the Diamond Light Source linac	204
	C. Christou Diamond, Oxfordshire, United Kingdom
	The Diamond pre-injector linac uses two 5.2 m DESY linac II-type accelerating structures to generate a 100 MeV electron beam suitable for injection into the booster synchrotron. The structures are powered independently by two high-power S-band klystrons and are designed to operate at 3 GHz. Higher order modes up to 14 GHz induced by beam in unpowered accelerating and bunching structures have been directly measured using directional couplers in the high-power waveguide network. These modes are compared with an electromagnetic simulation of the structures. The negative impact of higher-order wakes on the bunch trains used at Diamond is considered, and the use of the multipole field measurement for alignment of the beam to the structure is investigated.
MOPB017	Integration of the European XFEL Accelerating Modules	207
	E. Vogel, S. Barbanotti, J. Branlard, H. Brueck, S. Choroba, L. Hagge, K. Jensch, V.V. Katalev, D. Kostin, D. Käfer, L. Lilje, A. Matheisen, W.-D. Möller, D. Nölle, B. Petersen, J. Prenting, D. Reschke, H. Schlarb, M. Schmökel, J.K. Sekutowicz, W. Singer, H. Weise DESY, Hamburg, Germany J. Świerbleski, P.B. Borowiec IFJ-PAN, Kraków, Poland S. Berry, O. Napoly, B. Visentin CEA/DSM/IRFU, France A. Bosotti, P. Michelato INFN/LASA, Segrate (MI), Italy W. Kaabi LAL, Orsay, France C. Madec CEA/IRFU, Gif-sur-Yvette, France E.P. Plawski NCBJ, Świerk/Otwock, Poland F. Toral CIEMAT, Madrid, Spain
	The production of the 103 superconducting accelerating modules for the European XFEL is an international effort. Institutes and companies from seven different countries (China, France, Germany, Italy, Poland, Russia and Spain), organized in 12 different work packages contribute with parts, capacity for work and facilities to the production of the modules. Currently the series production of the individual parts started or is approaching. Personnel are trained for the assembly and testing of parts and as well for the complete modules. Here we present an overview and the status of all these activities.
MOPB018	Analyzing Surface Roughness Dependence of Linear RF Losses	210
	C. Xu The College of William and Mary, Williamsburg, USA M.J. Kelley, C.E. Reece JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Topographic structure on Superconductivity Radio Frequency (SRF) surfaces can contribute additional cavity RF losses describable in terms of surface RF reflectivity and absorption indices of wave scattering theory. At isotropic homogeneous extent, Power Spectrum Density (PSD) of roughness is introduced and quantifies the random surface topographic structure. PSD obtained from different surface treatments of niobium, such as Buffered Chemical Polishing (BCP), Electropolishing (EP), Nano-Mechanical Polishing (NMP) and Barrel Centrifugal Polishing (CBP) are compared. A perturbation model is utilized to calculate the additional rough surface RF losses based on PSD statistical analysis. This model will not consider that superconductor becomes normal conducting at fields higher than transition field. One can calculate the RF power dissipation ratio between rough surface and ideal smooth surface within this field range from linear loss mechanisms.
MOPB021	Bunch-by-bunch Phase Modulation for Linac Beam-loading Compensation	216
	G. Huang, D. Jia, K. Jin, H. Lin, Weishi, Zhou. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China Y. Liu USTC, Hefei, Anhui, People's Republic of China
	Funding: supported by NSFC-CAS Joint Fund, contract no. 11079034 If the linac is loaded by a high current, long pulse multi-bunch beam, the energy of the beam drops with time during the pulse. The bunch phase modulation method is introduced to compensate the beam loading. In this method the beam phase in the RF accelerating filed is changed bunch-by-bunch, the beam energy gain in the RF filed gradually grows up, which cancels the drop due to beam loading. The relationship between the beam phase distribution and the linac parameters is calculated in this paper.
MOPB022	RF Characteristic Studies on the Whole Accelerating Structure for the BEPCII Linear Accelerator	219
	S. Pei, M. Hou, X. Li, J.R. Zhang IHEP, Beijing, People's Republic of China B.L. Wang SINAP, Shanghai, People's Republic of China
	An accelerating structure is one device to boost the particle energy. 2856 MHz 3 m long travelling wave disk-loaded accelerating structure is applied in BEPCII linac, its RF characteristics are mainly determined by the 84 regular cells located between the input and output couplers. Input and output couplers need to be included when the whole structure RF characteristics are simulated before fabrication; otherwise it would be difficult to obtain the travelling wave fields excited in the whole structure. If the real 3D couplers are modelled during the design process, a large amount of computer resources and time need to be used. However, if the redesigned azimuth symmetric coupler is used to replace the real 3D one during the simulation process, much less computer resources and time are required. With this method proposed here, the simulation results agree well with the theoretically calculated and experimentally measured ones. *peisl@ihep.ac.cn
MOPB023	Progress on the Design and Construction of the 100 MeV / 100 kW Electron Linac for the NSC KIPT Neutron Source	222
	S. Pei, J. Cao, Y.L. Chi, B. Deng, C.D. Deng, H.S. Guo, D.Y. He, X. He, M. Hou, X.C. Kong, Q. Le, X. Li, J. Liu, R.L. Liu, W.B. Liu, K. Lv, C. Ma, H.Z. Ma, G. Pei, H. Song, L. Wang, S.H. Wang, X. Wang, Q. Yang, J. Yue, J.R. Zhang, F. Zhao, J.B. Zhao, J.X. Zhao, Z.S. Zhou IHEP, Beijing, People's Republic of China M.I. Ayzatskiy, I.M. Karnaukhov, V.A. Kushnir, V.V. Mytrochenko, A.Y. Zelinsky NSC/KIPT, Kharkov, Ukraine Y. Gohar ANL, Argonne, USA
	IHEP in China is designing and constructing a 100 MeV / 100 kW electron linac for NSC KIPT, which will be used as the driver of a neutron source based on a subcritical assembly. Recently, the physical design has been finalized. The chicane scheme instead of the RF chopper one has been selected. The mechanical design is on-going and will be finished in the very near future. The injector part of the machine has been installed in the experimental hall #2 of IHEP and is being commissioned and tested. The progress on the machine design and construction are reported, initial testing and commissioning results of the injector are also presented. *peisl@ihep.ac.cn
MOPB024	Beam Dynamics Simulation and Optimization for 10 MeV Superconducting e-Linac Injector for VECC-RIB Facility	225
	A. Chakrabarti, S. Dechoudhury, V. Naik VECC, Kolkata, India F. Ames, R.A. Baartman, Y.-C. Chao, R.E. Laxdal, M. Marchetto, L. Merminga, F. Yan TRIUMF, Vancouver, Canada G. Goh SFU, Burnaby, BC, Canada
	Funding: This project is funded by Department of Atomic Energy, India In the first phase of ongoing collaboration between VECC (India) and TRIUMF (Canada) a 10 MeV superconducting electron linac injector will be installed at VECC. This will constitute a 100 keV DC thermionic gun with grid delivering pulsed electron beam at 650 MHz. Owing to low energy from the gun, a capture cryo-module (CCM) consisting of two β = 1 single cell elliptical cavities (frequency = 1.3 GHz) will be inserted before a 9-cell β = 1 elliptical cavity that will provide acceleration to 10 MeV. The present paper depicts the beam dynamics simulation and optimization of different parameters for the injector with a realistic simulated beam emittance from the electron gun.
MOPB025	1ms Multi-bunch Electron Beam Acceleration by a Normal Conducting RF Gun and Superconducting Accelerator	228
	M. Kuriki, S. Hosoda, H. Iijima HU/AdSM, Higashi-Hiroshima, Japan H. Hayano, J. Urakawa, K. Watanabe KEK, Ibaraki, Japan G. Isoyama, R. Kato, K. Kawase ISIR, Osaka, Japan S. Kashiwagi Tohoku University, Research Center for Electron Photon Science, Sendai, Japan A. Kuramoto Sokendai, Ibaraki, Japan K. Sakaue RISE, Tokyo, Japan
	Funding: Quantum Beam Project by MEXT, Japan We perform electron beam generation and acceleration of 1 ms long pulse and multi-bunch format at KEK-STF (Superconducting Test Facility). The 1 ms long pulse beam is generated by a normal conducting photo-cathode L-band RF gun. The beam is boosted up to 40 MeV by a super-conducting accelerator. Aim of STF is to establish the super-conducting accelerator technology for ILC (International Linear Collider). The facility is concurrently used to demonstrate high brightness X-ray generation by inverse laser Compton scattering supported by MEXT Quantum Beam project. The RF gun cavity has been fabricated by DESY-FNAL-KEK collaboration. After conditioning process, a stable operation of the cavity up to 4.0 MW RF input with 1 ms pulse was achieved by keeping low dark current. 1 ms pulse generation and acceleration has been confirmed in March 2012. Quasi-monochromatic X-ray generation experiment by Laser-Compton will be carried out at STF from the next coming July. We report the latest status of STF.
MOPB026	TRIUMF/VECC e-Linac Injector Beam Test	231
	R.E. Laxdal, F. Ames, Y.-C. Chao, K. Fong, C. Gong, A. Laxdal, M. Marchetto, W.R. Rawnsley, S. Saminathan, V.A. Verzilov, Q. Zheng, V. Zvyagintsev TRIUMF, Vancouver, Canada J.M. Abernathy, D. Karlen, D.W. Storey Victoria University, Victoria, B.C., Canada A. Chakrabarti, V. Naik VECC, Kolkata, India
	TRIUMF is collaborating with VECC on the design of a 10 MeV injector cryomodule to be used as a front end for a high intensity electron linac. A electron gun and low energy beam transport (LEBT) have been installed in a test area to act as the injector for the cryomodule test. The LEBT includes a wide variety of diagnostics to fully characterize the beam from the gun. A series of beam tests are being conducted during the stage installation. The test configuration details and results of beam tests will be presented.
MOPB029	Commissioning of the X-Band Test Area at SLAC	234
	C. Limborg-Deprey, C. Adolphsen, M.P. Dunning, S. Gilevich, C. Hast, R.K. Jobe, D.J. McCormick, A. Miahnahri, T.O. Raubenheimer, A.E. Vlieks, D.R. Walz, S.P. Weathersby SLAC, Menlo Park, California, USA
	Funding: Work supported by the U.S. Department of Energy under contract DE-AC02-76SF00515. The X-Band Test Area (XTA) is being assembled in the NLCTA tunnel at SLAC to serve as a test facility for new X-Band RF guns. The first gun to be tested is an upgraded version of the 5.6 cell, 200 MV/m peak field X-band gun designed at SLAC in 2003 for the Compton Scattering experiment run in ASTA [1]. The XTA beamline is equipped with diagnostics to measure both the longitudinal phase space and the transverse phase space properties of the beam after it has reached 100 MeV. We will review design choices and present some early commissioning results. [1] A.E. Vlieks, et al. “Recent measurements and plans for the SLAC Compton X-ray source”, SLAC-PUB-11689, 2006. 10pp. Published in AIP Conf. Proc.807:481-490, 2006
MOPB030	Performance of First C100 Cryomodules for the CEBAF 12 GeV Upgrade Project	237
	M.A. Drury, A. Burrill, G.K. Davis, J. Hogan, L.K. King, F. Marhauser, H. Park, J.P. Preble, C.E. Reece, A.V. Reilly, R.A. Rimmer, H. Wang, M. Wiseman JLAB, Newport News, Virginia, USA
	Funding: This manuscript has been authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The Thomas Jefferson National Accelerator Facility is currently engaged in the 12 GeV Upgrade Project. The goal of the project is a doubling of the available beam energy of CEBAF from 6 GeV to 12 GeV. This increase in beam energy will be due primarily to the construction and installation of ten “C100” cryomodules in the CEBAF linacs. The C100 cryomodules are designed to deliver an average 108 MV each from a string of eight seven-cell, electropolished superconducting RF cavities operating at an average accelerating gradient of 19.2 MV/m. The new cryomodules fit in the same available linac space as the original CEBAF 20 MV cryomodules. Cryomodule production started in September 2010. Initial acceptance testing started in June 2011. The first two C100 cryomodules were installed and tested from August 2011 through October 2011, and successfully operated during the last period of the CEBAF 6 GeV era, which ended in May 2012. This paper will present the results of acceptance testing and commissioning of the C100 style cryomodules to date.
MOPB031	Vibration Response Testing of the CEBAF 12 GeV Upgrade Cryomodules	240
	G.K. Davis, J. Matalevich, T. Powers, M. Wiseman JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177 The CEBAF 12 GeV upgrade project includes 80 new 7-cell cavities assembled into 10 cryomodules. These cryomodules were tested during production to characterize their microphonic response in situ. For several early cryomodules, detailed (vibration) modal studies of the cryomodule string were performed during the assembly process to identify the structural contributors to the measured cryomodule microphonic response. Structural modifications were then modeled, implemented, and verified by subsequent modal testing and in-situ microphonic response testing. Interim and final results from this multi-stage process will be reviewed.
MOPB032	Stabilization of the Beam Intensity in the Linac at the CTF3 CLIC Test Facility	243
	A. Dubrovskiy JINR, Dubna, Moscow Region, Russia B.N. Bathe, S. Srivastava BARC, Mumbai, India F. Tecker CERN, Geneva, Switzerland
	A new electron beam stabilization system has been introduced in CTF3 in order to open new possibilities for CLIC beam studies in ultra-stable conditions and to provide a sustainable tool to keep the beam intensity and energy at its reference values for long term operations. The stabilization system is based on a pulse-to-pulse feedback control of the electron gun to compensate intensity deviations measured at the end of the injector and at the beginning of the linac. Thereby it introduces negligible beam distortions at the end of the linac and it significantly reduces energy deviations. A self-calibration mechanism has been developed to automatically configure the feedback controller for the optimum performance. The residual intensity jitter of 0.045% of the stabilized beam was measured whereas the CLIC requirement is 0.075%.
MOPB033	High Power Coupler Test for TRIUMF E-linac SC Cavities	246
	A.K. Mitra, Z.T. Ang, S. Calic, P.R. Harmer, S.R. Koscielniak, R.E. Laxdal, W.R. Rawnsley, R.W. Shanks TRIUMF, Vancouver, Canada
	TRIUMF has been funded to build an electron linac with a final energy of 50 MeV and 500 kW beam power using TESLA type 9 cell superconducting cavities operating at 1.3 GHz at 2 Kelvin. The e-linac consists of an electron gun, buncher cavity, injector cryomodule, and two main-linac cryomodules. The injector module has one 9-cell cavity whereas each of the accelerating main-linac cryomodules contains two 9-cell cavities. It is scheduled to install the injector and one main accelerating cryomodule by 2014. Six power couplers, each rated for 60 kW cw, have been procured for three cavities. The injector cryomodule will be fed by a 30 kW cw inductive Output Tube (IOT) and the accelerating cryomodule will be powered by a 290 kW cw klystron. In order to install the power couplers in the cavities, they are to be assembled and conditioned with high power rf source. A power coupler test station has been built and tests of two power couplers have began. A 30 kW IOT has been commissioned to full output power and it will be used for the power coupler test. In this paper, test results of the rf conditioning of the power couplers under pulse and cw mode will be described.
WE1A03	Application of X-band Linacs	724
	G. D'Auria ELETTRA, Basovizza, Italy
	Since the late 80’s the development of Normal Conducting (NC) X-band technology for particle accelerators has made significant progress and has witnessed tremendous growth. The driving force behind this technological development has been, and is, the interest of the scientific community in the construction of a Multi-TeV e+e− Linear Collider at a reasonable size and cost. The use of the X-band frequency allows for a much higher accelerating gradient per meter, when compared to the S and C bands. SLAC, with a major contribution from KEK, has been pioneering this development since the late 80’s in the framework of the NLC/JLC projects. Later, in 2007, the same technology was chosen by CERN for CLIC, the 12 GHz Linear Collider based on the Two-Beam Acceleration (TBA) concept. In addition to these applications, X-band technology is also rapidly expanding in the field of X-ray FELs and other photon sources where it shows great potential. Here, a selection of X-band projects as well as the main applications of this technology at different international laboratories, is reported. The paper also includes a brief report on X-band medical and industrial applications.
	Slides WE1A03 [5.826 MB]
WE1A04	The ARIEL Superconducting Electron Linac	729
	S.R. Koscielniak, F. Ames, R.A. Baartman, I.V. Bylinskii, Y.-C. Chao, D. Dale, R.J. Dawson, E.R. Guetre, N. Khan, A. Koveshnikov, A. Laxdal, R.E. Laxdal, F. Mammarella, M. Marchetto, L. Merminga, A.K. Mitra, T. Planche, Y.-N. Rao, A. Sitnikov, V.A. Verzilov, D. Yosifov, V. Zvyagintsev TRIUMF, Vancouver, Canada D. Karlen, R.R. Langstaff Victoria University, Victoria, B.C., Canada
	The TRIUMF Advanced Rare Isotope Laboratory (ARIEL) is funded since 2010 June by federal and BC Provincial governments. In collaboration with the University of Victoria, TRIUMF is proceeding with construction of a new target building, connecting tunnel, rehabilitation of an existing vault to contain the electron linear accelerator, and a cryogenic compressor building. TRIUMF starts construction of a 300 keV thermionic gun, and 10 MeV Injector cryomodule (EINJ) in 2012; the designs being complete. The 25 MeV Accelerator Cryomodule (EACA) follows in autumn 2013. TRIUMF is embarking on major equipment purchases and has signed contracts for 4K cryogenic plant and four sub-atmospheric pumps, a 290 kW c.w. klystron and high-voltage power supply, 80 quadrupole magnets, EINJ tank and lid, and four 1.3 GHz niobium 9-cell cavities from a local Canadian supplier. The low energy beam transport and beam diagnotics are being installed at the ISAC-II/VECC test facility. Procurement is anticipated October 2012 for the liquid He distribution system.
	Slides WE1A04 [4.305 MB]