THPLB —  Poster Orals   (13-Sep-12   15:00—16:00)

Paper	Title	Page
THPLB01	Linac Construction for China Spallation Neutron Source	807
	S. Fu, J. Li, H.C. Liu, H.F. Ouyang, X. Yin IHEP, Beijing, People's Republic of China
	Construction of China Spallation Neutron Source(CSNS) has been launched in September 2011. CSNS accelerator will provide 100kW proton beam on a target at beam energy of 1.6GeV. It consists of an 80MeV H− linac and 1.6GeV rapid cycling synchrotron. Based on the prototyping experience, CSNS linac, including the front end and four DTL tanks, has finalized the design and started procurement. In this paper, we will first present an outline of the CSNS accelerator in its design and construction plan. Then the major prototyping results of the linac will be presented. Finally the linac construction progress in recent will be updated.
	Slides THPLB01 [1.969 MB]
THPLB02	Performance of Ferrite Vector Modulators in the LLRF system of the Fermilab HINS 6-Cavity Test	810
	P. Varghese, B.W. Barnes, B. Chase, E. Cullerton, C.C. Tan Fermilab, Batavia, USA
	The High Intensity Neutrino Source (HINS) 6-cavity test is a part of the Fermilab HINS Linac R&D program for a low energy, high intensity proton/H− linear accelerator. One of the objectives of the 6-cavity test is to demonstrate the use of high power RF Ferrite Vector Modulators(FVM) for independent control of multiple cavities driven by a single klystron. The beamline includes an RFQ and six cavities. The LLRF system provides a primary feedback loop around the RFQ and the distribution of the regulated klystron output is controlled by secondary learning feed-forward loops on the FVMs for each of the six cavities. The feed-forward loops provide pulse to pulse correction to the current waveform profiles of the FVM power supplies to compensate for beam-loading and other disturbances. The learning feed-forward loops are shown to successfully control the amplitude and phase settings for the cavities well within the 1 % and 1 degree requirements specified for the system.
	Slides THPLB02 [1.610 MB]
THPLB03	Front-End Linac Design and Beam Dynamics Simulations for MYRRHA	813
	C. Zhang, H. Klein, D. Mäder, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede, M. Vossberg IAP, Frankfurt am Main, Germany
	Funding: Funded by the European Atomic Energy Community’s (Euratom) 7th Framework Programme under Grant Agreement n°269565. A 17MeV, 176MHz, and CW (Continuous Wave) proton linac is being developed as the front end of the driver accelerator for the MYRRHA facility in Mol, Belgium. Based on the promising preliminary design, further simulation and optimization studies have been performed with respect to code benchmarking, RFQ simulation using realistic LEBT output distributions, and an updated CH-DTL design with more detailed inter-tank configurations. This paper summarizes the new results.
	Slides THPLB03 [1.292 MB]
THPLB04	Preliminary Study of Proton Beam Transport in a 10 MeV Dielectric Wall Accelerator	816
	J. Zhu, S. Chen, J. Deng, Y. Shen, J. Shi, W.D. Wang, L.S. Xia, H. Zhang, L.W. Zhang CAEP/IFP, Mainyang, Sichuan, People's Republic of China
	Funding: Nuclear Energy Technology Development project; National Natural Science Foundation of China (11035004) A novel proton accelerator based on Dielectric Wall Accelerator (DWA) technology is being developed at Institute of Fluid Physics (IFP). The accelerating gradient will be 20 MV/m or even higher based on current high gradient insulator (HIG) performance. Theoretical study and numerical simulation of accelerating the proton beam to 10 MeV by virtual traveling wave method is presented in this paper. The beam dynamics under accelerating pulse with or without flattop is discussed.
	Slides THPLB04 [1.191 MB]
THPLB05	R&D Activities on High Intensity Superconducting Proton Linac at RRCAT	819
	S.C. Joshi, J. Dwivedi, P.D. Gupta, P.R. Hannurkar, P. Khare, P.K. Kush, G. Mundra, A. Puntambekar, S.B. Roy, P. Shrivastava RRCAT, Indore (M.P.), India
	Raja Ramanna Centre for Advanced Technology (RRCAT), Indore has taken up a program on development of 1 GeV high intensity superconducting proton linac for Spallation Neutron Source. This will require several multi-cell superconducting cavities operating at different RF frequencies. To start with, a number of single-cell prototype cavities at 1.3 GHz have been developed in high RRR bulk niobium. These single-cell cavities have exhibited high quality factor and accelerating gradients. Superconducting properties of niobium are being studied for varying composition of impurities and different processing conditions. Development activity on solid state RF amplifiers to power the SCRF cavities at various RF frequencies is being pursued. A building has been constructed to house the SCRF cavity fabrication and processing facility. To characterize SCRF cavity, a 2 K Vertical Test Stand is being set up including a 2 K cryostat, RF power supply and data acquisition system. Design activities for cryomodule and large 2 K cryostat for Horizontal Test Stand are also under progress. The paper will discuss the status of above R&D activities and infrastructure development at RRCAT.
	Slides THPLB05 [1.614 MB]
THPLB06	The New Option for a Front End of Ion Linac	822
	A.D. Kovalenko JINR, Dubna, Moscow Region, Russia A. Kolomiets ITEP, Moscow, Russia
	The standard ion linac front-end consisting of RFQ, two tanks of accelerating IH-structures, MEBTs with matching and focusing elements is modified to achieve better performances. Special vane section that provides the same beam transformation as debuncher and quadrupole triplet is added within the RFQ tank, whereas superconducting focusing elements, solenoids, for example, are used between the IH - structure tanks. Test frond end was designed to provide the output beam energy up to 4 MeV/u for the particles with charge-to-mass ratio of 0.16 < q/m ≤ 1. Results of beam dynamics simulation are presented. Possible application of the considered scheme for the NICA facility at JINR (Dubna, Russia) is discussed.
	Slides THPLB06 [0.482 MB]
THPLB07	Experience with a 4-Rod CW Radio Frequency Quadrupole	825
	P. Gerhard, W.A. Barth, L.A. Dahl, W. Hartmann, G. Schreiber, W. Vinzenz, H. Vormann GSI, Darmstadt, Germany
	Since 1991 the High Charge State Injector (HLI) provides heavy ion beams for the linear accelerator UNILAC at GSI*. It is equipped with an ECR ion source and an RFQ-IH linac which accelerates highly charged ion beams with high duty factor of up to 30% to 1.4 MeV/u for further acceleration in the Alvarez DTL of the UNILAC. Main user of these beams is the Super Heavy Element (SHE) research, one of the outstanding projects at GSI**. Experiments like TASCA and SHIP strongly benefit from the high average beam intensities. After two decades of successful operation the four-rod Radio Frequency Quadrupole (RFQ) accelerator was replaced in 2010 by a newly designed RFQ of the same type**. Besides higher beam transmission, the principal intention of this upgrade was to raise the duty factor up to 100%, since the HLI is foreseen as injector for the upcoming cw linac dedicated to the SHE program**. Commissioning and operational experience from the first years revealed that this goal could not be reached easily. In this paper we present the RFQ design, commissioning results, operational experience and future activities. * N. Angert et al., EPAC92, Berlin, Germany (1992), p. 167 ** L. Dahl et al., LINAC10, Tsukuba, Japan (2010), MOP042, and references therein
	Slides THPLB07 [0.986 MB]
THPLB08	High-Power RF Conditioning of the TRASCO RFQ	828
	E. Fagotti, L. Antoniazzi, F. Grespan, A. Palmieri INFN/LNL, Legnaro (PD), Italy M. Desmons CEA/DSM/IRFU, France
	The TRASCO RFQ is designed to accelerate a 40 mA proton beam up to 5 MeV. It is a CW machine which has to show stable operation and provide the requested availability. It is composed of three electromagnetic segment coupled via two coupling cells. Each segment is divided into two 1.2 m long OFE copper modules. The RFQ is fed through eight loop-based power couplers to deliver RF to the cavity from a 352.2 MHZ, 1.3 MW klystron. After couplers conditioning, the first electromagnetic segment was successfully tested at full power. RFQ cavity reached the nominal 68 kV inter-vane voltage (1.8 Kilp.) in CW operation. Moreover, during conditioning in pulsed operation, it was possible to reach 83 kV inter-vane voltage (2.2 Kilp.) with a 1% duty cycle. The description of the experimental setup and procedure, as well as the main results of the conditioning procedure will be reported in this paper.
	Slides THPLB08 [1.384 MB]
THPLB09	Status of E-XFEL String and Cryomodule Assembly at CEA-Saclay	831
	C. Madec CEA, Gif-sur-Yvette, France S. Berry, J.-P. Charrier, A. Daël, M. Fontaine, Y. Gasser, O. Napoly, Y. Sauce, C.S. Simon, T.V. Vacher, B. Visentin CEA/DSM/IRFU, France A. Brasseur, P. Charon, C. Cloué, S. Langlois, G. Monnereau, J.L. Perrin, D. Roudier, N. Sacépé CEA/IRFU, Gif-sur-Yvette, France
	As In-Kind contributor to E-XFEL project, CEA is committed to the integration on the Saclay site of the 100 cryomodules of the superconducting linac as well as to the procurement of the magnetic shieldings, superinsulation blankets and 31 cold beam position monitors of the re-entrant type. The assembly infrastructure has been renovated from the previous Saturne Synchrotron Laboratory facility: it includes a 200 m2 clean room complex with 120 m2 under ISO4, 1325 m2 of assembly platforms and 400 m2 of storage area. In parallel, CEA has conducted industrial studies and three cryomodule assembly prototyping both aiming at preparing the industrial file, the quality management system and the commissioning of the assembly plant, tooling and control equipments. In 2012, the contract of the integration will be placed to a subcontractor. The paper will summarize the outputs of the preparation and prototyping phases and the up-coming industrial phase.
THPLB11	Experimental and Simulation Study of the Long-path-length Dynamics of a Space-charge-dominated Bunch	834
	I. Haber, B.L. Beaudoin, S. Bernal, R.A. Kishek, T.W. Koeth, Y. Mo UMD, College Park, Maryland, USA
	Funding: Work supported by the United States Department of Energy and the Office of Naval Research. The University of Maryland Electron Ring (UMER) is a low-energy (10 keV) electron facility built to study, on a scaled machine, the long-propagation-length evolution of a space-charge-dominated beam. Though constructed in a ring geometry to achieve a long path length at modest cost, UMER has observed important space-charge physics directly relevant to linear machines. Examples will be presented that emphasize studies of the longitudinal dynamics and comparisons to axisymmetric simulations. The detailed agreement obtained between simulation and experiment will be presented as evidence that the longitudinal physics observed is not strongly influenced by the ring geometry. Novel phenomena such as soliton formation, unimpeded bunch-end interpenetration, and an instability that occurs after this interpenetration, will be discussed.
THPLB12	Photoinjector SRF Cavity Development for BERLinPro	837
	A. Neumann, W. Anders, T. Kamps, J. Knobloch HZB, Berlin, Germany E.N. Zaplatin FZJ, Jülich, Germany
	In 2010 HZB has received approval to build BERLinPro, an ERL project to demonstrate energy recovery at 100 mA beam current by pertaining a high quality beam. These goals place stringent requirements on the SRF cavity for the photoinjector which has to deliver a small emittance 100 mA beam with at least 1.5 MeV kinetic energy while limited by fundamental power coupler performance to about 200 kW forward power. In oder to achieve these goals the injector cavity is being developed in a three stage approach. The current design studies focus on implementing a normal conducting cathode insert into a newly developed superconducting photoinjector cavity. In this paper the fundamental RF design calculations concerning cell shape for optimized beam dynamics as well as SRF performance will be presented. Further studies concentrate on the HZDR based choke cell design to implement the high quantum efficiency normal conducting cathode with the SRF cavity.
	Slides THPLB12 [1.431 MB]