IPAC2013 - List of Keywords (DTL)

Paper	Title	Other Keywords	Page
MOPFI025	Progress Towards High-Intensity Heavy-Ion Beams at RIKEN RIBF	ion, cyclotron, stripper, ECRIS	333
	O. Kamigaito, T. Dantsuka, M. Fujimaki, T. Fujinawa, N. Fukunishi, H. Hasebe, Y. Higurashi, E. Ikezawa, H. Imao, T. Kageyama, M. Kase, M. Kidera, M. Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, T. Nakagawa, M. Nakamura, J. Ohnishi, H. Okuno, K. Ozeki, N. Sakamoto, K. Suda, H. Watanabe, T. Watanabe, Y. Watanabe, K. Yamada, H. Yamasawa RIKEN Nishina Center, Wako, Japan
	The RIKEN RIBF(Radioactive Isotope Beam Factory) accelerator complex has been designed and constructed to provide heavy-ion beams from D to U ions with the energy of 400 MeV/u to the maximum. Though the goal intensity is 1 particle μ amperes for the whole mass range, the intensities of very heavy-ions from Ca to U are still not satisfactory. In 2012, owing to the intensity upgrade of ⁴⁸Ca beams from ECR ion source, the beam current of ⁴⁸Ca was 400 pnA which was improved by factors of 2 in comparison with that in 2011. Since 2011, the new injector RILAC2 has been successfully commissioned and operated very stably for beam service time, increasing the U beam intensity by an order of magnitude. Because it was no longer realistic to use carbon foil to strip the charge of intense U beams, in 2012 the Low-Z gas stripper system instead of the standard carbon foil system has been introduced and successfully worked. To accelerate the ²³⁸U⁶⁴⁺ beams provided by the Low-Z gas stripper, modification of the following Fixed-frequency Ring Cyclotron was performed. In 2012, 15 pnA uranium beams which was four times larger than that provided in 2011 has been achieved.

MOPME026	Beam Monitor Layout for Future ACS Section in J-PARC Linac	linac, cavity, beam-transport, monitoring	529
	A. Miura, M. Ikegami, H. Oguri JAEA/J-PARC, Tokai-mura, Japan
	In J-PARC Linac, an energy and intensity upgrade project has started since 2009 using Annular Coupled Structure (ACS) cavities. With this upgrade, the design peak current will be increased from the present 30 mA to 50 mA, and the energy from 181 MeV to 400 MeV. Along with these significant upgrades of the beam parameters, beam monitors should be followed. Also, the bunch shape monitor and new beam loss monitoring system will be employed for the new beam line. Newly fabricated devices will be delivered in the ACS beam line. And beam monitor layout of the upstream and downstream of ACS beam line will be modified. In this paper, we introduce the development of the beam diagnostic devices for the project and the new designed beam monitor layout.

MOPWO013	A New Scalable Software Package for Large Scale Beam Dynamic Simulations	simulation, space-charge, target, solenoid	912
	R. Zhao, J. Xu IS, Beijing, People's Republic of China Y. He, C. Li, X. Qi, L. Yang IMP, Lanzhou, People's Republic of China
	Large scale Beam Dynamics Simulations (BDS) are important in accelerator design and optimization. With the fast development of supercomputers, new software packages need to be developed in order to fully make use of hardware and software progresses. In this paper, we will introduce a new BDS software package, LOCUS3D, which is developed for efficient use of these new techniques. It is based on Particle-In-Cell (PIC) method, and includes space charge effect by solving the Poisson’s equation. Parallel Poisson solver has been developed with MPI. Standard accelerator devices can be simulated and new devices can be added. Benchmark results have been obtained on several different platforms, such as INSPUR cluster at RDCPS, BG/P at ANL. Large-scale simulation with 10⁹ particles can be simulated now in the simulations. LOCUS3D will be used for more realistic accelerator simulations in the near future.

MOPWO085	A Hybrid Technique for Computing Courant-Snyder Parameters from Beam Profile Data	space-charge, emittance, simulation, linac	1073
	C.K. Allen ORNL, Oak Ridge, Tennessee, USA E.N. Dai Washington University in St. Louis, St. Louis, USA
	Funding: Work supported by ORNL/SNS, which is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725. We present a technique for computing the Courant-Snyder parameters of a charged-particle beam from profile measurement data. Such algorithms are not new, but this particular method has very robust convergence properties resulting from a novel approach that combines both deterministic and non-deterministic methods. The general idea is as follows: given a model of the beamline, in the zero-current case it is possible to compute the Courant-Snyder parameters directly from profile data using a deterministic, linear-algebraic approach. For the finite beam current case we can construct a smooth curve of these deterministic solutions starting from the zero-current solution and terminating at the finite-current case. We are guaranteed convergence, and convergence to the finite-current solution connected to the zero-current Courant-Snyder parameters. This approach avoids the convergence issues associated with a fully iterative, non-deterministic method. The details of the technique are outlined and examples are presented using profile data taken from the SNS accelerator.

TUPWA007	Method and Results of Systematic Beam Matching to a Periodic DTL	emittance, resonance, focusing, quadrupole	1733
	L. Groening, W.A. Barth, P. Forck, I. Hofmann, S.G. Yaramyshev GSI, Darmstadt, Germany D. Jeon IBS, Daejeon, Republic of Korea
	Systematic investigations on high current 3d-beam matching to a periodic Alvarez-type DTL are reported. Twiss parameters at the entrance of a matching section to the periodic structure were concluded from transverse and longitudinal measurements. Periodic solutions in 3d were calculated including space charge using the measured rms emittances. The matching was performed by rms beam size tracking and employing a numerical routine to set the matching section, which comprises five quadrupoles and two bunchers. Matching allowed for significant emittance growth reduction and for verification of non-linear beam dynamics effects along the DTL.

TUPWA019	Comparison of Tracking Simulation with Experiment on the GSI UNILAC	emittance, simulation, linac, space-charge	1763
	X. Yin IHEP, Beijing, People's Republic of China W.A. Barth, W.B. Bayer, L. Groening, I. Hofmann, S.G. Richter, S.G. Yaramyshev GSI, Darmstadt, Germany A. Franchi CERN, Geneva, Switzerland A.C. Sauer IAP, Frankfurt am Main, Germany
	In the European framework “High Intensity Pulsed Proton Injector” (HIPPI), the 3D linac code comparison and benchmarking program with experiment have been initialed. PARMILA and HALODYN are involved in this work. Both of these codes have been developed and used for linac design and beam dynamics studies. In this paper, we compare the simulation results with experiment results which was carried out on the UNILAC Alvarez DTL. And discuss physics aspects of the different linac design and beam dynamics simulation codes.

TUPWO016	Beam Dynamics Design of 3 MeV Medium Energy Beam Transport for Beam Intensity Upgrade of J-PARC Linac	emittance, simulation, cavity, linac	1916
	T. Maruta KEK/JAEA, Ibaraki-Ken, Japan M. Ikegami J-PARC, KEK & JAEA, Ibaraki-ken, Japan
	The J-PARC linac has a plan to upgrade its beam power in the summer 2013. This plan includes the replacement of the front-end components (ion source and 3 MeV RFQ) to increase the peak current from present 30 mA to 50 mA. Since it results in the different injection beam profile to medium energy beam transport (MEBT), which locates the RFQ downstream, we designed the beam dynamics of MEBT. In this presentation, we disscuss the new design of beam dynamics in MEBT.

WEOBB101	The KOMAC Accelerator Facility	linac, proton, klystron, rfq	2052
	Y.-S. Cho, J.-H. Jang, D.I. Kim, H.S. Kim, H.-J. Kwon, B.-S. Park, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun KAERI, Daejon, Republic of Korea
	Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government. The development of the Korea Multi-purpose Accelerator Complex (KOMAC) accelerator facility was finished and went into the operation period from 2013. The facility consists of an 100-MeV proton linac including a 50-keV ion source, a 3-MeV RFQ, and a 100-MeV DTL, and 20-MeV and 100-MeV beam lines. The linac and beam lines were developed by the Proton Engineering Frontier Project (PEFP), the first phase of KOMAC from 2002 to 2012. The goal of the beam commissioning is delivering 100-MeV 1-kW proton beams to a beam bump in a 100-MeV target room. After finishing the commissioning, the user beam service will start from spring 2013. The KOMAC user facility consists of 2 beam lines in the initial operation stage and it will be increased to 10 beam lines in future. The one beam line is for 20-MeV proton beams which are extracted after 20-MeV part of the DTL tanks. A medium energy beam transport (MEBT) is installed there for the 20-MeV beam extraction and the beam matching to the next DTL tank. The other beam line is for 100-MeV proton beams. This work summarized the status of the KOMAC accelerator and beam lines.
	Slides WEOBB101 [6.038 MB]

WEPFI017	Performance of Cavity Phase Monitor at J-PARC Linac	cavity, linac, pick-up, LLRF	2738
	K. Futatsukawa, S. Anami, Z. Fang, Y. Fukui, T. Kobayashi, S. Michizono KEK, Ibaraki, Japan F. Sato, S. Shinozaki JAEA/J-PARC, Tokai-mura, Japan
	The amplitude and the phase stabilities of the RF system play an important role for the cavity of a high intensity proton accelerator. For the J-PARC Linac, the accelerating field ambiguity must be maintained within ±1% in amplitude and ±1 degree in phase due to the momentum acceptance of the next synchrotron. To realize the requirement, a digital feedback (FB) control is used in the low level RF (LLRF) control system, and a feed-forward (FF) technique is combined with the FB control for the beam loading compensation. The stability of ±0.2% in amplitude and ±0.2 degree in phase of the cavity was achieved including the beam loading in a macro pulse. Additionally, the cavity phase monitors, which can measure the phase difference between any two cavities, were installed in summer, 2011. The monitor has the three different types, which are for the present 324-MHz RF system, the 972-MHz RF system and the combined system of 324-MHz RF and 972-MHz RF. The phase monitor for the 324-MHz RF has been in operated since Dec. 2011. We would like to introduce the phase monitor and indicate the phase stability at the J-PARC linac.

WEPFI079	Electromagnetic Modeling of RF Drive in the LANSCE DTL	cavity, coupling, simulation, HOM	2878
	S.S. Kurennoy LANL, Los Alamos, New Mexico, USA
	A 3D electromagnetic model of the RF drive module in the LANSCE DTL tank 4 has been developed with the CST MicroWave Studio. The model is explored both with eigensolver and in time domain to evaluate maximal fields in the drive module and RF coupling. Here we describe the model and present simulation results.

THPFI041	Installation and Operation of the Beamlines for the 100-MeV Proton Linac	proton, linac, alignment, site	3376
	B.-S. Park, Y.-S. Cho, J.-H. Jang, D.I. Kim, H.S. Kim, H.-J. Kwon, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun KAERI, Daejon, Republic of Korea
	Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government. Beamlines and 100-MeV proton linac have been developed for 1st phase of KOMAC(Korea Multi-purpose Accelerator Complex) at the Gyeong-ju site. The linac supply either 20-MeV or 100-MeV proton beams for beam applications. Each proton beam can be transported to 2 beamlines for industrial purpose and 3 beamlines for various researches. At the first phase, 2 beamlines were installed and under test. A detailed description of the installation and the preliminary test results will be presented in this paper.

THPME012	Measuring the Direction of Permanent Magnet Easy Axis by Helmholtz Coil	quadrupole, permanent-magnet, multipole, linac	3534
	X.Y. Jia, S.X. Zheng TUB, Beijing, People's Republic of China
	Permanent magnets for quadrupole focusing was used in drift-tube linac of the Compact Pulsed Hadron Sources(CPHS) in Tsinghua university. In order to ensure the accuracy of the quadrupole field can meet the design requirement, we need measure the strength and direction of remanence and choose the suit magnet. This paper proposed an easy way to get the direction of permanent magnet easy axis by Helmholtz coil without knowing the angle between magnet and the axis of the coil: the magnet rotational angle data was measured by rotary encoder and encoder would send trigger signal every turn at the same direction. First we started to record data when trigger signal was appeared. Then measured the magnet in three perpendicular directions (x,y,z). Last, caculated the remanence in three directions. We had measured some magnet by the new method and obtained satisfactory results.

THPWO008	Status of the 70 MeV FAIR Proton Injector	proton, linac, rfq, cavity	3773
	G. Clemente, W.A. Barth, R. Bereznov, P. Forck, L. Groening, R. Hollinger, M. Kaiser, A. Krämer, F. Maimone, C. Mühle, J. Pfister, G. Schreiber, J. Trüller, W. Vinzenz, C. Will GSI, Darmstadt, Germany R. M. Brodhage, B. Koubek, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede IAP, Frankfurt am Main, Germany N. Chauvin, O. Delferrière CEA/IRFU, Gif-sur-Yvette, France B. Launé, J. Lesrel IPN, Orsay, France C.S. Simon, O. Tuske CEA/DSM/IRFU, France
	Funding: BMBF The FAIR project requires a dedicated proton injector for the creation of high intensity secondary antiproton beams. This machine will be the first high intensity linear accelerator based on CH-DTL. The status of the project, with particular emphasis on the construction of the first RF prototype is presented.

THPWO009	Beam Dynamics Error and Loss Investigation of the FAIR Proton Injector	linac, rfq, proton, quadrupole	3776
	G. Clemente, W.A. Barth, P. Forck, L. Groening, R. Hollinger, M. Kaiser, J. Pfister, W. Vinzenz, S.G. Yaramyshev, C. Zhang GSI, Darmstadt, Germany R. M. Brodhage, B. Koubek, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede IAP, Frankfurt am Main, Germany N. Chauvin, C.S. Simon, O. Tuske CEA/DSM/IRFU, France O. Delferrière CEA/IRFU, Gif-sur-Yvette, France B. Launé, J. Lesrel IPN, Orsay, France
	The FAIR Proton Linac is a 70mA, 70 MeV. 325 MHz linear accelerator based on CH cavities. The focusing scheme is provided by an asynchronous KONUS lattice period. Random misalignment and rotation errors of the quadrupoles, together with phase and RF settings of the power source plays a major role in beam losses. Those effects are investigated and the beam dynamics results, including several source of errors, are presented and discussed.

THPWO012	High Gradient Room Temperature Cavity Development for 10 – 100 AMeV Beams	cavity, linac, focusing, ion	3785
	A. Almomani, U. Ratzinger IAP, Frankfurt am Main, Germany
	Funding: BMBF, 05P12RFRB9 These linac activities are aimed to increase the accelerating field gradient. In IAP – Frankfurt, a CH – design was proposed to post-accelerate a proton bunch, generated by an intense laser, from 10 – 15.2 MeV. The accelerating field gradient is expected to reach > 10 MV/m. Within a funded project, this cavity will be further developed towards a high gradient cavity. The availability of the GSI 3 MW klystron test stand will be very important for these investigations. The results will influence the rebuilt of the Unilac - Alvarez section, where the existing linac tunnel with 1 m thick concrete walls should house a powerful pulsed heavy ion linac, optimized for achieving finally the beam intensities specified for the GSI-FAIR project. The status of the cavity design will be presented.

THPWO017	A Coupled RFQ-IH Cavity for the Neutron Source FRANZ	rfq, linac, simulation, cavity	3797
	M. Heilmann, C. Claessens, O. Meusel, D. Mäder, U. Ratzinger, A. Schempp, M. Schwarz IAP, Frankfurt am Main, Germany
	The Frankfurt neutron Source at the Stern-Gerlach-Zentrum (FRANZ) delivers neutrons in the energy range from 1 to 300 keV at high intensities. The neutrons are produced using the the 7Li(p,n)7Be reaction with 2 MeV protons. The linac accelerator cavities consists of a 4-rod-RFQ coupled with an 8 gap interdigital H-type drift tube section with a total cavity length of 2.3 m. It accelerates the 120 keV beam to 2.03 MeV at a frequency of 175 MHz. The combined cavity will be powered by one RF amplifier to reduce investment and operation costs. The inductive power coupler will be located at the RFQ part. The coupling into the IH – section is provided by direct inductive coupling within the cavity. The coupled RFQ-IH combination is investigated with CST-MWS-simulations and by an RF model. The linac combination has to match the resonance frequency, flatness along the RFQ and the voltage ratio between both cavity sections. Beam operation will be cw (a few mA) and pulsed 250 kHz, 50 ns (up to 50 mA and beyond). The thermal cavity losses are about 200 kW and the cooling is the challenging topic.

THPWO024	PROGRESS ON DTL DESIGN FOR ESS	linac, multipole, emittance, simulation	3815
	M. Comunian, F. Grespan, A. Pisent, C. Roncolato INFN/LNL, Legnaro (PD), Italy R. De Prisco ESS, Lund, Sweden P. Mereu INFN-Torino, Torino, Italy
	In the European Spallation Source (ESS) accelerator, the Drift Tube Linac (DTL) will accelerate a proton beam of 50 mA pulse peak current from 3 to ~80 MeV. In this paper the engineering design of DTL tanks with the beam dynamics errors studies and the RF design are shown.

THPWO028	Commissioning Plan for Energy Upgrade of J-PARC Linac	linac, acceleration, injection, quadrupole	3821
	M. Ikegami, Z. Fang, K. Futatsukawa, T. Miyao KEK, Ibaraki, Japan Y. Liu KEK/JAEA, Ibaraki-Ken, Japan T. Maruta J-PARC, KEK & JAEA, Ibaraki-ken, Japan A. Miura, J. Tamura JAEA/J-PARC, Tokai-mura, Japan
	In J-PARC linac, we plan to have an energy and intensity upgrade in summer 2013. The upgrade involves replacement of the ion source and RFQ (Radio Frequency Quadrupole linac), and addition of ACS (Annular Coupled Structure linac) cavities after existing SDTL (Separate Drift Tube Linac) section. With this upgrade, the design peak current will be increased from the present 30 mA to 50 mA, and the energy from 181 MeV to 400 MeV. This significant upgrade will be followed by a full-scale beam commissioning campaign. In this paper, we present the plan for the commissioning with outlining the assumed commissioning schemes.

THPWO029	Beam Loss Monitoring and Mitigation at J-PARC DTL	radiation, linac, injection, vacuum	3824
	T. Maruta J-PARC, KEK & JAEA, Ibaraki-ken, Japan K. Futatsukawa, M. Ikegami, T. Miyao KEK, Ibaraki, Japan T. Ito, A. Miura JAEA/J-PARC, Tokai-mura, Japan
	Close radiation survey at the cavity outer surface has indicated a significant beam loss in the first tank of J-PARC DTL (Drift Tube Linac) which has been localized at a certain drift tube. It has motivated us to measure the beam loss at the DTL, and we have installed beam loss monitors of scintillator type at the cavity surface. It is challenging to monitor the beam loss due to low energy of lost particles and shielding by the thick cavity wall. In this paper, we report the results of beam loss measurement and beam loss mitigation tuning using the beam loss monitors.

THPWO030	Recent Progress in Beam Commissioning of J-PARC Linac	linac, resonance, simulation, radiation	3827
	M. Ikegami, Z. Fang, K. Futatsukawa, T. Miyao KEK, Ibaraki, Japan Y. Liu KEK/JAEA, Ibaraki-Ken, Japan T. Maruta J-PARC, KEK & JAEA, Ibaraki-ken, Japan A. Miura, J. Tamura JAEA/J-PARC, Tokai-mura, Japan
	The beam operation of J-PARC linac has been restored from the earthquake, and started to pursue higher beam power operation. We have also started to prepare for coming energy and intensity upgrade. In this paper, we review recent progress in beam commissioning of J-PARC linac with emphasis on the beam loss mitigation and preparation for the upgrade.

THPWO045	Commissioning Plan for the CSNS Linac	linac, emittance, diagnostics, quadrupole	3869
	J. Peng, S. Fu, J. Li, Y. Li, H.C. Liu, H.F. Ouyang, N. Wang, S. Wang, T.G. Xu IHEP, Beijing, People's Republic of China
	The linac of the China Spallation Neutron Source(CSNS) will be commissioned from October 2013. The linac will be commissioned in three phases. The delivery of beam to the RCS is planned for October 2015. This paper describes the commissioning plans for the MEBT and DTL parts of the linac. Techniques for finding the RF set-point, matching and steering are presented, as well as codes to assist in the beam commissioning.

THPWO046	The Preparation for the Commissioning of CSNS Accelerators	injection, linac, optics, target	3872
	S. Wang, S. Fu, H.F. Ouyang, J. Peng IHEP, Beijing, People's Republic of China
	The China Spallation Neutron Source (CSNS) is now under construction, and the beam commissioning of ion source will start from the end of 2013, and will last several years for whole accelerators. The commissioning plan for the CSNS accelerators will be presented, including the commissioning correlated parameters, beam instrumentation in used commissioning, the goal at different commissioning stages. The development of high level application software will also be presented.

THPWO056	A 5.3 MeV/U, 200MHz APF DTL for Carbon Ions as an Injector of Medical Synchrotron	synchrotron, focusing, cavity, emittance	3890
	P. Jiang, Y.J. Yuan IMP, Lanzhou, People's Republic of China
	A new low energy medium frequency DTL for 12C⁵⁺ with alternative phase focusing method (APF), which has advantage in compact space and low cost, was designed as an injector of medical synchrotron. There is no conventional focusing elements in the APF DTL, and transversal focusing is realized using RF field by varying synchronous phase instead. The envelopes of beam size are presented and the emittance change of six-dimension phase space is shown. The simple method proposed by Y. Iwata was used to create synchronous phase array. Since the motion between transversal and longitudinal plains are coupled, the longitudinal acceptance of the DTL is not large.

THPWO059	Beam Dynamics Design of the Main Accelerating Section with KONUS in the CSR-LINAC Proposal	linac, emittance, rfq, heavy-ion	3895
	X.H. Zhang, H. Du, J.W. Xia, X. Yin, Y.J. Yuan IMP, Lanzhou, People's Republic of China
	The CSR-LINAC as the injector of the Cooling Storage Ring (CSR) has been proposed in Heavy Ion Research Facility in Lanzhou (HIRFL). The injection linac mainly consists of two Linacs, the Radio Frequency Quadrupole linac (RFQ) and the Drift Tube Linac (DTL). The KONUS (Kombinierte Null Grad Struktur) concept has been introduced to the drift tube linac section. In this paper, the re-matching of the main accelerating section will be finished in the 3.7MeV/u scheme and the new beam dynamics design updating to 7MeV/u will be shown. Through the beam re-matching, the relative emittance growth has been suppressed greatly along the linac. The KONUS structure is also adopted in the beam dynamics design that update from 3.7MeV/u to 7MeV/u and the good beam quality and transmission is shown.

THPWO066	Beam Commissioning of KOMAC Linac	linac, proton, rfq, simulation	3909
	J.-H. Jang, Y.-S. Cho, D.I. Kim, H.S. Kim, H.-J. Kwon, B.-S. Park, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun KAERI, Daejon, Republic of Korea
	Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government. The proton engineering frontier project (PEFP), which is the first phase of Korea multi-purpose accelerator complex (KOMAC), developed a 100-MeV proton linac which consists of a 50 keV injector, a 3-MeV radio frequency quadrupole (RFQ) and a 100-MeV drift tube linac (DTL). The installation of the linac was finished in 2012. The goal of the beam commissioning in spring 2013 is accelerating 100-MeV proton beams with the beam power of 1 kW to the beam dump which is located downstream of the linac. This work summarized the beam commissioning result for the linac.

THPWO068	Resonance Frequency Control Characteristics of the 100-MeV Drift Tube Linac	controls, resonance, proton, linac	3912
	H.-J. Kwon, Y.-S. Cho, J.-H. Jang, H.S. Kim, K.T. Seol, Y.-G. Song KAERI, Daejon, Republic of Korea
	Funding: This work was supported by the Ministry of Science and Technology of the Korean Government. A 100-MeV, 20mA proton accelerator has been developed by KAERI (Korea Atomic Energy Institute). Total 11 DTL (Drift Tube Linac) tanks are used to accelerator the proton beam from 3-MeV to 100-MeV. A RCCS (Resonance frequency Control Cooling System) has been developed to control the resonance frequency of each DTL tank. The coolant for the drift tube and quadrupole magnets are supplied by the RCCS, whereas the wall coolant temperature maintains constant at 27 degree C by using the DI water supplied from the utility. In this paper, the resonance frequency control schemes are summarized and the control characteristics of the DTL tank by using the RCCS are discussed.

THPWO070	ESS DTL RF MODELIZATION: FIELD TUNING AND STABILIZATION	linac, cavity, target, quadrupole	3918
	R. De Prisco ESS, Lund, Sweden M. Comunian, F. Grespan, A. Pisent INFN/LNL, Legnaro (PD), Italy A.R. Karlsson Lund University, Lund, Sweden
	The Radio Frequency (RF) design of Drift Tube Linac (DTL) of the European Spallation Source, ESS, has been defined in order to satisfy the accelerating field requirements of beam dynamic studies and to reduce peak field levels in the critical areas. The electro-magnetic field is stabilized with post-couplers. The cells geometries of the DTL are optimized to accommodate permanent magnet quadrupoles (PMQ), to get maximum shunt impedance, to meet the Moretti criterion at the low energy part and to facilitate the mechanical construction.

THPWO074	Technical Design of the ESS Facility	linac, target, rfq, proton	3927
	S. Peggs ESS, Lund, Sweden
	The 5 MW European Spallation Source is entering a construction phase for the entire facility. This paper surveys the unique features, challenges and open issues that exist, from ion source to target, and from moderator to instruments. It is consistent with the ESS-wide Technical Design Report, published in April 2013. The paper is presented on behalf of the ESS consortium, and all the contributors to the ESS TDR.

THPWO075	Beam Loss Limits in High Power Proton Linear Accelerators	proton, rfq, radiation, linac	3930
	L. Tchelidze ESS, Lund, Sweden J. Stovall STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
	High power hadron linear accelerators are designed based on 1 W/m loss limit criteria. The loss limit originates from the hands-on-maintenance allowance of the accelerators and limits average dose rate level to less than 0.1 - 1 mSv/hr at 30 cm from a machine after 100 days of continuous operation and 4 hours of down time. However, machine activation and thus beam loss limit depends on incident particle energy and 1 W/m is only a good approximation for energies 100-200 MeV and higher (in H-/H⁺ accelerators). At lower energies though, one could allow much higher than 1 W/m without excess activation. A careful analysis of energy dependent loss limits was performed for proton linacs as part of the study for the European Spallation Source (ESS) linac, for energy ranges 5 MeV – 2.5 GeV. ESS linac is to be built in Lund, Sweden and will deliver 5 MW proton beam to the target. MARS code was used for calculations and beam loss limits were derived as a function of energy.

Paper

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Other Keywords

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MOPFI025

Progress Towards High-Intensity Heavy-Ion Beams at RIKEN RIBF

ion, cyclotron, stripper, ECRIS

333

O. Kamigaito, T. Dantsuka, M. Fujimaki, T. Fujinawa, N. Fukunishi, H. Hasebe, Y. Higurashi, E. Ikezawa, H. Imao, T. Kageyama, M. Kase, M. Kidera, M. Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, T. Nakagawa, M. Nakamura, J. Ohnishi, H. Okuno, K. Ozeki, N. Sakamoto, K. Suda, H. Watanabe, T. Watanabe, Y. Watanabe, K. Yamada, H. Yamasawa
RIKEN Nishina Center, Wako, Japan

The RIKEN RIBF(Radioactive Isotope Beam Factory) accelerator complex has been designed and constructed to provide heavy-ion beams from D to U ions with the energy of 400 MeV/u to the maximum. Though the goal intensity is 1 particle μ amperes for the whole mass range, the intensities of very heavy-ions from Ca to U are still not satisfactory. In 2012, owing to the intensity upgrade of ⁴⁸Ca beams from ECR ion source, the beam current of ⁴⁸Ca was 400 pnA which was improved by factors of 2 in comparison with that in 2011. Since 2011, the new injector RILAC2 has been successfully commissioned and operated very stably for beam service time, increasing the U beam intensity by an order of magnitude. Because it was no longer realistic to use carbon foil to strip the charge of intense U beams, in 2012 the Low-Z gas stripper system instead of the standard carbon foil system has been introduced and successfully worked. To accelerate the ²³⁸U⁶⁴⁺ beams provided by the Low-Z gas stripper, modification of the following Fixed-frequency Ring Cyclotron was performed. In 2012, 15 pnA uranium beams which was four times larger than that provided in 2011 has been achieved.

MOPME026

Beam Monitor Layout for Future ACS Section in J-PARC Linac

linac, cavity, beam-transport, monitoring

529

A. Miura, M. Ikegami, H. Oguri
JAEA/J-PARC, Tokai-mura, Japan

In J-PARC Linac, an energy and intensity upgrade project has started since 2009 using Annular Coupled Structure (ACS) cavities. With this upgrade, the design peak current will be increased from the present 30 mA to 50 mA, and the energy from 181 MeV to 400 MeV. Along with these significant upgrades of the beam parameters, beam monitors should be followed. Also, the bunch shape monitor and new beam loss monitoring system will be employed for the new beam line. Newly fabricated devices will be delivered in the ACS beam line. And beam monitor layout of the upstream and downstream of ACS beam line will be modified. In this paper, we introduce the development of the beam diagnostic devices for the project and the new designed beam monitor layout.

MOPWO013

A New Scalable Software Package for Large Scale Beam Dynamic Simulations

simulation, space-charge, target, solenoid

912

R. Zhao, J. Xu
IS, Beijing, People's Republic of China
Y. He, C. Li, X. Qi, L. Yang
IMP, Lanzhou, People's Republic of China

Large scale Beam Dynamics Simulations (BDS) are important in accelerator design and optimization. With the fast development of supercomputers, new software packages need to be developed in order to fully make use of hardware and software progresses. In this paper, we will introduce a new BDS software package, LOCUS3D, which is developed for efficient use of these new techniques. It is based on Particle-In-Cell (PIC) method, and includes space charge effect by solving the Poisson’s equation. Parallel Poisson solver has been developed with MPI. Standard accelerator devices can be simulated and new devices can be added. Benchmark results have been obtained on several different platforms, such as INSPUR cluster at RDCPS, BG/P at ANL. Large-scale simulation with 10⁹ particles can be simulated now in the simulations. LOCUS3D will be used for more realistic accelerator simulations in the near future.

MOPWO085

A Hybrid Technique for Computing Courant-Snyder Parameters from Beam Profile Data

space-charge, emittance, simulation, linac

1073

C.K. Allen
ORNL, Oak Ridge, Tennessee, USA
E.N. Dai
Washington University in St. Louis, St. Louis, USA

Funding: Work supported by ORNL/SNS, which is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
We present a technique for computing the Courant-Snyder parameters of a charged-particle beam from profile measurement data. Such algorithms are not new, but this particular method has very robust convergence properties resulting from a novel approach that combines both deterministic and non-deterministic methods. The general idea is as follows: given a model of the beamline, in the zero-current case it is possible to compute the Courant-Snyder parameters directly from profile data using a deterministic, linear-algebraic approach. For the finite beam current case we can construct a smooth curve of these deterministic solutions starting from the zero-current solution and terminating at the finite-current case. We are guaranteed convergence, and convergence to the finite-current solution connected to the zero-current Courant-Snyder parameters. This approach avoids the convergence issues associated with a fully iterative, non-deterministic method. The details of the technique are outlined and examples are presented using profile data taken from the SNS accelerator.

TUPWA007

Method and Results of Systematic Beam Matching to a Periodic DTL

emittance, resonance, focusing, quadrupole

1733

L. Groening, W.A. Barth, P. Forck, I. Hofmann, S.G. Yaramyshev
GSI, Darmstadt, Germany
D. Jeon
IBS, Daejeon, Republic of Korea

Systematic investigations on high current 3d-beam matching to a periodic Alvarez-type DTL are reported. Twiss parameters at the entrance of a matching section to the periodic structure were concluded from transverse and longitudinal measurements. Periodic solutions in 3d were calculated including space charge using the measured rms emittances. The matching was performed by rms beam size tracking and employing a numerical routine to set the matching section, which comprises five quadrupoles and two bunchers. Matching allowed for significant emittance growth reduction and for verification of non-linear beam dynamics effects along the DTL.

TUPWA019

Comparison of Tracking Simulation with Experiment on the GSI UNILAC

emittance, simulation, linac, space-charge

1763

X. Yin
IHEP, Beijing, People's Republic of China
W.A. Barth, W.B. Bayer, L. Groening, I. Hofmann, S.G. Richter, S.G. Yaramyshev
GSI, Darmstadt, Germany
A. Franchi
CERN, Geneva, Switzerland
A.C. Sauer
IAP, Frankfurt am Main, Germany

In the European framework “High Intensity Pulsed Proton Injector” (HIPPI), the 3D linac code comparison and benchmarking program with experiment have been initialed. PARMILA and HALODYN are involved in this work. Both of these codes have been developed and used for linac design and beam dynamics studies. In this paper, we compare the simulation results with experiment results which was carried out on the UNILAC Alvarez DTL. And discuss physics aspects of the different linac design and beam dynamics simulation codes.

TUPWO016

Beam Dynamics Design of 3 MeV Medium Energy Beam Transport for Beam Intensity Upgrade of J-PARC Linac

emittance, simulation, cavity, linac

1916

T. Maruta
KEK/JAEA, Ibaraki-Ken, Japan
M. Ikegami
J-PARC, KEK & JAEA, Ibaraki-ken, Japan

The J-PARC linac has a plan to upgrade its beam power in the summer 2013. This plan includes the replacement of the front-end components (ion source and 3 MeV RFQ) to increase the peak current from present 30 mA to 50 mA. Since it results in the different injection beam profile to medium energy beam transport (MEBT), which locates the RFQ downstream, we designed the beam dynamics of MEBT. In this presentation, we disscuss the new design of beam dynamics in MEBT.

WEOBB101

The KOMAC Accelerator Facility

linac, proton, klystron, rfq

2052

Y.-S. Cho, J.-H. Jang, D.I. Kim, H.S. Kim, H.-J. Kwon, B.-S. Park, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun
KAERI, Daejon, Republic of Korea

Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government.
The development of the Korea Multi-purpose Accelerator Complex (KOMAC) accelerator facility was finished and went into the operation period from 2013. The facility consists of an 100-MeV proton linac including a 50-keV ion source, a 3-MeV RFQ, and a 100-MeV DTL, and 20-MeV and 100-MeV beam lines. The linac and beam lines were developed by the Proton Engineering Frontier Project (PEFP), the first phase of KOMAC from 2002 to 2012. The goal of the beam commissioning is delivering 100-MeV 1-kW proton beams to a beam bump in a 100-MeV target room. After finishing the commissioning, the user beam service will start from spring 2013. The KOMAC user facility consists of 2 beam lines in the initial operation stage and it will be increased to 10 beam lines in future. The one beam line is for 20-MeV proton beams which are extracted after 20-MeV part of the DTL tanks. A medium energy beam transport (MEBT) is installed there for the 20-MeV beam extraction and the beam matching to the next DTL tank. The other beam line is for 100-MeV proton beams. This work summarized the status of the KOMAC accelerator and beam lines.

Slides WEOBB101 [6.038 MB]

WEPFI017

Performance of Cavity Phase Monitor at J-PARC Linac

cavity, linac, pick-up, LLRF

2738

K. Futatsukawa, S. Anami, Z. Fang, Y. Fukui, T. Kobayashi, S. Michizono
KEK, Ibaraki, Japan
F. Sato, S. Shinozaki
JAEA/J-PARC, Tokai-mura, Japan

The amplitude and the phase stabilities of the RF system play an important role for the cavity of a high intensity proton accelerator. For the J-PARC Linac, the accelerating field ambiguity must be maintained within ±1% in amplitude and ±1 degree in phase due to the momentum acceptance of the next synchrotron. To realize the requirement, a digital feedback (FB) control is used in the low level RF (LLRF) control system, and a feed-forward (FF) technique is combined with the FB control for the beam loading compensation. The stability of ±0.2% in amplitude and ±0.2 degree in phase of the cavity was achieved including the beam loading in a macro pulse. Additionally, the cavity phase monitors, which can measure the phase difference between any two cavities, were installed in summer, 2011. The monitor has the three different types, which are for the present 324-MHz RF system, the 972-MHz RF system and the combined system of 324-MHz RF and 972-MHz RF. The phase monitor for the 324-MHz RF has been in operated since Dec. 2011. We would like to introduce the phase monitor and indicate the phase stability at the J-PARC linac.

WEPFI079

Electromagnetic Modeling of RF Drive in the LANSCE DTL

cavity, coupling, simulation, HOM

2878

S.S. Kurennoy
LANL, Los Alamos, New Mexico, USA

A 3D electromagnetic model of the RF drive module in the LANSCE DTL tank 4 has been developed with the CST MicroWave Studio. The model is explored both with eigensolver and in time domain to evaluate maximal fields in the drive module and RF coupling. Here we describe the model and present simulation results.

THPFI041

Installation and Operation of the Beamlines for the 100-MeV Proton Linac

proton, linac, alignment, site

3376

B.-S. Park, Y.-S. Cho, J.-H. Jang, D.I. Kim, H.S. Kim, H.-J. Kwon, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun
KAERI, Daejon, Republic of Korea

Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government.
Beamlines and 100-MeV proton linac have been developed for 1st phase of KOMAC(Korea Multi-purpose Accelerator Complex) at the Gyeong-ju site. The linac supply either 20-MeV or 100-MeV proton beams for beam applications. Each proton beam can be transported to 2 beamlines for industrial purpose and 3 beamlines for various researches. At the first phase, 2 beamlines were installed and under test. A detailed description of the installation and the preliminary test results will be presented in this paper.

THPME012

Measuring the Direction of Permanent Magnet Easy Axis by Helmholtz Coil

quadrupole, permanent-magnet, multipole, linac

3534

X.Y. Jia, S.X. Zheng
TUB, Beijing, People's Republic of China

Permanent magnets for quadrupole focusing was used in drift-tube linac of the Compact Pulsed Hadron Sources(CPHS) in Tsinghua university. In order to ensure the accuracy of the quadrupole field can meet the design requirement, we need measure the strength and direction of remanence and choose the suit magnet. This paper proposed an easy way to get the direction of permanent magnet easy axis by Helmholtz coil without knowing the angle between magnet and the axis of the coil: the magnet rotational angle data was measured by rotary encoder and encoder would send trigger signal every turn at the same direction. First we started to record data when trigger signal was appeared. Then measured the magnet in three perpendicular directions (x,y,z). Last, caculated the remanence in three directions. We had measured some magnet by the new method and obtained satisfactory results.

THPWO008

Status of the 70 MeV FAIR Proton Injector

proton, linac, rfq, cavity

3773

G. Clemente, W.A. Barth, R. Bereznov, P. Forck, L. Groening, R. Hollinger, M. Kaiser, A. Krämer, F. Maimone, C. Mühle, J. Pfister, G. Schreiber, J. Trüller, W. Vinzenz, C. Will
GSI, Darmstadt, Germany
R. M. Brodhage, B. Koubek, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede
IAP, Frankfurt am Main, Germany
N. Chauvin, O. Delferrière
CEA/IRFU, Gif-sur-Yvette, France
B. Launé, J. Lesrel
IPN, Orsay, France
C.S. Simon, O. Tuske
CEA/DSM/IRFU, France

Funding: BMBF
The FAIR project requires a dedicated proton injector for the creation of high intensity secondary antiproton beams. This machine will be the first high intensity linear accelerator based on CH-DTL. The status of the project, with particular emphasis on the construction of the first RF prototype is presented.

THPWO009

Beam Dynamics Error and Loss Investigation of the FAIR Proton Injector

linac, rfq, proton, quadrupole

3776

G. Clemente, W.A. Barth, P. Forck, L. Groening, R. Hollinger, M. Kaiser, J. Pfister, W. Vinzenz, S.G. Yaramyshev, C. Zhang
GSI, Darmstadt, Germany
R. M. Brodhage, B. Koubek, H. Podlech, U. Ratzinger, A. Schempp, R. Tiede
IAP, Frankfurt am Main, Germany
N. Chauvin, C.S. Simon, O. Tuske
CEA/DSM/IRFU, France
O. Delferrière
CEA/IRFU, Gif-sur-Yvette, France
B. Launé, J. Lesrel
IPN, Orsay, France

The FAIR Proton Linac is a 70mA, 70 MeV. 325 MHz linear accelerator based on CH cavities. The focusing scheme is provided by an asynchronous KONUS lattice period. Random misalignment and rotation errors of the quadrupoles, together with phase and RF settings of the power source plays a major role in beam losses. Those effects are investigated and the beam dynamics results, including several source of errors, are presented and discussed.

THPWO012

High Gradient Room Temperature Cavity Development for 10 – 100 AMeV Beams

cavity, linac, focusing, ion

3785

A. Almomani, U. Ratzinger
IAP, Frankfurt am Main, Germany

Funding: BMBF, 05P12RFRB9
These linac activities are aimed to increase the accelerating field gradient. In IAP – Frankfurt, a CH – design was proposed to post-accelerate a proton bunch, generated by an intense laser, from 10 – 15.2 MeV. The accelerating field gradient is expected to reach > 10 MV/m. Within a funded project, this cavity will be further developed towards a high gradient cavity. The availability of the GSI 3 MW klystron test stand will be very important for these investigations. The results will influence the rebuilt of the Unilac - Alvarez section, where the existing linac tunnel with 1 m thick concrete walls should house a powerful pulsed heavy ion linac, optimized for achieving finally the beam intensities specified for the GSI-FAIR project. The status of the cavity design will be presented.

THPWO017

A Coupled RFQ-IH Cavity for the Neutron Source FRANZ

rfq, linac, simulation, cavity

3797

M. Heilmann, C. Claessens, O. Meusel, D. Mäder, U. Ratzinger, A. Schempp, M. Schwarz
IAP, Frankfurt am Main, Germany

The Frankfurt neutron Source at the Stern-Gerlach-Zentrum (FRANZ) delivers neutrons in the energy range from 1 to 300 keV at high intensities. The neutrons are produced using the the 7Li(p,n)7Be reaction with 2 MeV protons. The linac accelerator cavities consists of a 4-rod-RFQ coupled with an 8 gap interdigital H-type drift tube section with a total cavity length of 2.3 m. It accelerates the 120 keV beam to 2.03 MeV at a frequency of 175 MHz. The combined cavity will be powered by one RF amplifier to reduce investment and operation costs. The inductive power coupler will be located at the RFQ part. The coupling into the IH – section is provided by direct inductive coupling within the cavity. The coupled RFQ-IH combination is investigated with CST-MWS-simulations and by an RF model. The linac combination has to match the resonance frequency, flatness along the RFQ and the voltage ratio between both cavity sections. Beam operation will be cw (a few mA) and pulsed 250 kHz, 50 ns (up to 50 mA and beyond). The thermal cavity losses are about 200 kW and the cooling is the challenging topic.

THPWO024

PROGRESS ON DTL DESIGN FOR ESS

linac, multipole, emittance, simulation

3815

M. Comunian, F. Grespan, A. Pisent, C. Roncolato
INFN/LNL, Legnaro (PD), Italy
R. De Prisco
ESS, Lund, Sweden
P. Mereu
INFN-Torino, Torino, Italy

In the European Spallation Source (ESS) accelerator, the Drift Tube Linac (DTL) will accelerate a proton beam of 50 mA pulse peak current from 3 to ~80 MeV. In this paper the engineering design of DTL tanks with the beam dynamics errors studies and the RF design are shown.

THPWO028

Commissioning Plan for Energy Upgrade of J-PARC Linac

linac, acceleration, injection, quadrupole

3821

M. Ikegami, Z. Fang, K. Futatsukawa, T. Miyao
KEK, Ibaraki, Japan
Y. Liu
KEK/JAEA, Ibaraki-Ken, Japan
T. Maruta
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
A. Miura, J. Tamura
JAEA/J-PARC, Tokai-mura, Japan

In J-PARC linac, we plan to have an energy and intensity upgrade in summer 2013. The upgrade involves replacement of the ion source and RFQ (Radio Frequency Quadrupole linac), and addition of ACS (Annular Coupled Structure linac) cavities after existing SDTL (Separate Drift Tube Linac) section. With this upgrade, the design peak current will be increased from the present 30 mA to 50 mA, and the energy from 181 MeV to 400 MeV. This significant upgrade will be followed by a full-scale beam commissioning campaign. In this paper, we present the plan for the commissioning with outlining the assumed commissioning schemes.

THPWO029

Beam Loss Monitoring and Mitigation at J-PARC DTL

radiation, linac, injection, vacuum

3824

T. Maruta
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
K. Futatsukawa, M. Ikegami, T. Miyao
KEK, Ibaraki, Japan
T. Ito, A. Miura
JAEA/J-PARC, Tokai-mura, Japan

Close radiation survey at the cavity outer surface has indicated a significant beam loss in the first tank of J-PARC DTL (Drift Tube Linac) which has been localized at a certain drift tube. It has motivated us to measure the beam loss at the DTL, and we have installed beam loss monitors of scintillator type at the cavity surface. It is challenging to monitor the beam loss due to low energy of lost particles and shielding by the thick cavity wall. In this paper, we report the results of beam loss measurement and beam loss mitigation tuning using the beam loss monitors.

THPWO030

Recent Progress in Beam Commissioning of J-PARC Linac

linac, resonance, simulation, radiation

3827

M. Ikegami, Z. Fang, K. Futatsukawa, T. Miyao
KEK, Ibaraki, Japan
Y. Liu
KEK/JAEA, Ibaraki-Ken, Japan
T. Maruta
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
A. Miura, J. Tamura
JAEA/J-PARC, Tokai-mura, Japan

The beam operation of J-PARC linac has been restored from the earthquake, and started to pursue higher beam power operation. We have also started to prepare for coming energy and intensity upgrade. In this paper, we review recent progress in beam commissioning of J-PARC linac with emphasis on the beam loss mitigation and preparation for the upgrade.

THPWO045

Commissioning Plan for the CSNS Linac

linac, emittance, diagnostics, quadrupole

3869

J. Peng, S. Fu, J. Li, Y. Li, H.C. Liu, H.F. Ouyang, N. Wang, S. Wang, T.G. Xu
IHEP, Beijing, People's Republic of China

The linac of the China Spallation Neutron Source(CSNS) will be commissioned from October 2013. The linac will be commissioned in three phases. The delivery of beam to the RCS is planned for October 2015. This paper describes the commissioning plans for the MEBT and DTL parts of the linac. Techniques for finding the RF set-point, matching and steering are presented, as well as codes to assist in the beam commissioning.

THPWO046

The Preparation for the Commissioning of CSNS Accelerators

injection, linac, optics, target

3872

S. Wang, S. Fu, H.F. Ouyang, J. Peng
IHEP, Beijing, People's Republic of China

The China Spallation Neutron Source (CSNS) is now under construction, and the beam commissioning of ion source will start from the end of 2013, and will last several years for whole accelerators. The commissioning plan for the CSNS accelerators will be presented, including the commissioning correlated parameters, beam instrumentation in used commissioning, the goal at different commissioning stages. The development of high level application software will also be presented.

THPWO056

A 5.3 MeV/U, 200MHz APF DTL for Carbon Ions as an Injector of Medical Synchrotron

synchrotron, focusing, cavity, emittance

3890

P. Jiang, Y.J. Yuan
IMP, Lanzhou, People's Republic of China

A new low energy medium frequency DTL for 12C⁵⁺ with alternative phase focusing method (APF), which has advantage in compact space and low cost, was designed as an injector of medical synchrotron. There is no conventional focusing elements in the APF DTL, and transversal focusing is realized using RF field by varying synchronous phase instead. The envelopes of beam size are presented and the emittance change of six-dimension phase space is shown. The simple method proposed by Y. Iwata was used to create synchronous phase array. Since the motion between transversal and longitudinal plains are coupled, the longitudinal acceptance of the DTL is not large.

THPWO059

Beam Dynamics Design of the Main Accelerating Section with KONUS in the CSR-LINAC Proposal

linac, emittance, rfq, heavy-ion

3895

X.H. Zhang, H. Du, J.W. Xia, X. Yin, Y.J. Yuan
IMP, Lanzhou, People's Republic of China

The CSR-LINAC as the injector of the Cooling Storage Ring (CSR) has been proposed in Heavy Ion Research Facility in Lanzhou (HIRFL). The injection linac mainly consists of two Linacs, the Radio Frequency Quadrupole linac (RFQ) and the Drift Tube Linac (DTL). The KONUS (Kombinierte Null Grad Struktur) concept has been introduced to the drift tube linac section. In this paper, the re-matching of the main accelerating section will be finished in the 3.7MeV/u scheme and the new beam dynamics design updating to 7MeV/u will be shown. Through the beam re-matching, the relative emittance growth has been suppressed greatly along the linac. The KONUS structure is also adopted in the beam dynamics design that update from 3.7MeV/u to 7MeV/u and the good beam quality and transmission is shown.

THPWO066

Beam Commissioning of KOMAC Linac

linac, proton, rfq, simulation

3909

J.-H. Jang, Y.-S. Cho, D.I. Kim, H.S. Kim, H.-J. Kwon, B.-S. Park, J.Y. Ryu, K.T. Seol, Y.-G. Song, S.P. Yun
KAERI, Daejon, Republic of Korea

Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government.
The proton engineering frontier project (PEFP), which is the first phase of Korea multi-purpose accelerator complex (KOMAC), developed a 100-MeV proton linac which consists of a 50 keV injector, a 3-MeV radio frequency quadrupole (RFQ) and a 100-MeV drift tube linac (DTL). The installation of the linac was finished in 2012. The goal of the beam commissioning in spring 2013 is accelerating 100-MeV proton beams with the beam power of 1 kW to the beam dump which is located downstream of the linac. This work summarized the beam commissioning result for the linac.

THPWO068

Resonance Frequency Control Characteristics of the 100-MeV Drift Tube Linac

controls, resonance, proton, linac

3912

H.-J. Kwon, Y.-S. Cho, J.-H. Jang, H.S. Kim, K.T. Seol, Y.-G. Song
KAERI, Daejon, Republic of Korea

Funding: This work was supported by the Ministry of Science and Technology of the Korean Government.
A 100-MeV, 20mA proton accelerator has been developed by KAERI (Korea Atomic Energy Institute). Total 11 DTL (Drift Tube Linac) tanks are used to accelerator the proton beam from 3-MeV to 100-MeV. A RCCS (Resonance frequency Control Cooling System) has been developed to control the resonance frequency of each DTL tank. The coolant for the drift tube and quadrupole magnets are supplied by the RCCS, whereas the wall coolant temperature maintains constant at 27 degree C by using the DI water supplied from the utility. In this paper, the resonance frequency control schemes are summarized and the control characteristics of the DTL tank by using the RCCS are discussed.

THPWO070

ESS DTL RF MODELIZATION: FIELD TUNING AND STABILIZATION

linac, cavity, target, quadrupole

3918

R. De Prisco
ESS, Lund, Sweden
M. Comunian, F. Grespan, A. Pisent
INFN/LNL, Legnaro (PD), Italy
A.R. Karlsson
Lund University, Lund, Sweden

The Radio Frequency (RF) design of Drift Tube Linac (DTL) of the European Spallation Source, ESS, has been defined in order to satisfy the accelerating field requirements of beam dynamic studies and to reduce peak field levels in the critical areas. The electro-magnetic field is stabilized with post-couplers. The cells geometries of the DTL are optimized to accommodate permanent magnet quadrupoles (PMQ), to get maximum shunt impedance, to meet the Moretti criterion at the low energy part and to facilitate the mechanical construction.

THPWO074

Technical Design of the ESS Facility

linac, target, rfq, proton

3927

S. Peggs
ESS, Lund, Sweden

The 5 MW European Spallation Source is entering a construction phase for the entire facility. This paper surveys the unique features, challenges and open issues that exist, from ion source to target, and from moderator to instruments. It is consistent with the ESS-wide Technical Design Report, published in April 2013.
The paper is presented on behalf of the ESS consortium, and all the contributors to the ESS TDR.

THPWO075

Beam Loss Limits in High Power Proton Linear Accelerators

proton, rfq, radiation, linac

3930

L. Tchelidze
ESS, Lund, Sweden
J. Stovall
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom

High power hadron linear accelerators are designed based on 1 W/m loss limit criteria. The loss limit originates from the hands-on-maintenance allowance of the accelerators and limits average dose rate level to less than 0.1 - 1 mSv/hr at 30 cm from a machine after 100 days of continuous operation and 4 hours of down time. However, machine activation and thus beam loss limit depends on incident particle energy and 1 W/m is only a good approximation for energies 100-200 MeV and higher (in H-/H⁺ accelerators). At lower energies though, one could allow much higher than 1 W/m without excess activation. A careful analysis of energy dependent loss limits was performed for proton linacs as part of the study for the European Spallation Source (ESS) linac, for energy ranges 5 MeV – 2.5 GeV. ESS linac is to be built in Lund, Sweden and will deliver 5 MW proton beam to the target. MARS code was used for calculations and beam loss limits were derived as a function of energy.