08 Applications of Accelerators
U01 Medical Applications

Paper	Title	Page
THXB201	Novel Techniques and Challenges in Hadron Therapy	3112
	Th. Haberer, E. Feldmeier, M. Galonska, A. Peters, C. Schömers HIT, Heidelberg, Germany
	This talk should review novel techniques and challenges for beam delivery systems with various beam scanning methods (such as 3D scanning, 4D scanning and so on) to conform the beam dose to the tumor shape in proton and carbon ion therapy, as developed by PSI, GSI, HIMAC, IMP etc. Besides traditional accelerators such as cyclotrons and synchrotrons, the talk should review the technical challenges and prospects for future compact hadron therapy accelerators such as DWA, laser accelerators and so on.
	Slides THXB201 [4.934 MB]
THOAB201	Development of the Dielectric Wall Accelerator	3115
	A. Zografos, T. Brown, C. Cohen-Jonathan, C. Hettler, F. Huang, V. Joshkin, K. Leung, M. Moyers, Y.K. Parker, D. Pearson, M. Rougieri CPAC, Livermore, CA, USA R.W. Hamm R&M Technical Enterprises, Pleasanton, California, USA
	The Compact Particle Accelerator Corporation has developed an architecture to produce pulsed proton bunches that will be suitable for proton beam therapy. The Dielectric Wall Accelerator engineering prototype includes a RFQ injection system with a pulsed kicker to select the desired proton bunches and a linear accelerator incorporating a High Gradient Insulator with stacked transmission to produce the required voltage. The transmission lines are switched with solid state laser driven optical switches. A computational model has been developed that is in very good agreement with the experimental results. The system is presently achieving accelerating gradients of approximately 15 MeV/m. The computational model has been used to design the next generation system that will achieve 25 MeV/m by early 2013. This paper will discuss the status of the apparatus, the basic elements of the computational model, experimental results and comparison to the model predictions. In addition, the paper will present concepts for proton therapy systems that incorporate the Dielectric Wall Accelerator and fully leverage its features to achieve clinical requirements.
	Slides THOAB201 [1.650 MB]
THOAB202	Secondary Neutron Production from Patients during Hadron Therapy and their Radiation Risks: the Other Side of Hadron Therapy	3118
	M.A. Chaudhri University of Erlangen-Nuernberg, Erlangen, Germany
	We were the first to calculate and measure the neutron produced from patients during therapy with bremsstrahlung, and estimated their radiation doses *. This neutron output would be lot higher with hadrons due to their larger cross sections. There is no reliable/ useful data on this subject. Using the experimental neutron production data from different body elements, we have estimated the fluence and energies of these neutrons from tissue under irradiation with different hadrons. Our results indicate that at least 4.2 neutrons , with energies greater than 5 MeV, are produced for every C-ion of 400 MeV/u energy incident on tissue. This number reduces to 3, 1.4 and 0.3 respectively at C-energies of 300, 200 and 100 MeV /u. For protons these numbers are estimated to be 0.05, 0.2 and 0.4 per proton of energies 100, 200 and 300 MeV respectively. There would be even more neutrons with energies lesser than 5 MeV. The doses to some organs have been estimated, which are not negligible. A “Compromise optimum energy” concept is suggested. But extreme caution is highly recommend before treating patients with hadrons, especially children and younger people who still have many years to live. * P.Allen and M.A Chaudhri, Phys. Med. Biol. 33 (1988) 1017
	Slides THOAB202 [3.644 MB]
THPWA001	Design of X-Band Medical Linear Accelerator with Multiple RF Feeds and RF Phase Focusing	3627
	Y. N. Nour El-Din, T.M. Abuelfadl Cairo University, Giza, Egypt
	Funding: Work supported by the Egyptian Science and Technology Development Fund (STDF) No. 953. A design of 6 MeV X-band 9.3 GHz medical linear accelerator is presented. It is composed of four separate clusters of accelerating cavities, where a coherent RF excitation is provided separately to each cluster. The use of multiple accelerating sections with multiple RF feeds permits the use of inexpensive RF sources. The first cluster is Alternate Phase Focusing (APF) RF cavities, providing radial and longitudinal beam focusing without the use of heavy and bulky magnets or solenoids. The three other clusters used for acceleration are composed of multiple standing wave sections operating in the Pi-mode. Each section has been designed and optimized for high shunt impedance by means of 2D SUPERFISH code and 3D CST code. A two dimensional code, named PTCC, was developed to facilitate design and analysis of the different parts of the accelerating structure.
THPWA004	The HIT Gantry: From Commissioning to Operation	3636
	M. Galonska, S. Brons, R. Cee, Th. Haberer, K. Höppner, J.M. Mosthaf, A. Peters, S. Scheloske, T. Winkelmann HIT, Heidelberg, Germany
	The patient treatment at the first 360° raster scanning heavy ion gantry of the Heidelberg Ion Therapy Facility (HIT) started in October 2012 using proton and carbon ion beams. HIT is the first dedicated proton and carbon cancer therapy facility in Europe. It uses full 3D intensity controlled raster scanning dose delivering method of pencil beams. The ion energy ranges from ~50 up to 430 MeV/u (ion penetration depths of 20 to 300 mm in water). Beams are provided by a linac-synchrotron-system to four high energy beam lines: 2 horizontal patient treatment rooms; 1 horizontal experimental cave for quality assurance, development, and research work; and the heavy ion gantry. From the first commissioning the libraries of carbon and proton pencil beams at the gantry had been offered with the whole variety of ion beam properties: 255 energy steps, 4 beam foci, 360°, and 10 intensities (106-1010/spill) regarding the central beam. This paper reflects the impact of the subsequent preclinical testing including beam size/position, and dose measurements within the irradiation field of 20x20 cm2 on the further improvement of the ion optical settings of the gantry high energy transfer line.
THPWA005	The HIT Accelerator as Part of a Medical Product: Impacts on the Maintenance Strategy	3639
	A. Peters, R. Cee, Th. Haberer, T. Winkelmann HIT, Heidelberg, Germany
	The HIT accelerator produces protons and carbon beams with a large variety of parameters: 255 different energies, four foci and ten intensity steps per ion are independently available at 5 iso-centres to be requested by the dose delivery system for tumor treatment. Thus the whole accelerator chain is part of a medical product, in case of HIT an in-house manufactured device. The overall risk and quality management has deep influences on the maintenance process. Not only the huge volume of necessary documentation reflects this impact but also the organizational process before, along and after the services at HIT. Especially, the comprehensive testing after the maintenance procedures follows sophisticated checklists (e.g. the ion source service). On the other hand, a high operational availability of the accelerator in a hospital is mandatory. To realize 8250 hours of accelerator uptime per year in case of HIT, a maintenance strategy is necessary, which interleaves the regular service of the building infrastructure, e.g. air conditioning, with the periodic maintenance of the accelerator components. In detail, this approach will be discussed along the magnets and the gantry structure.
THPWA008	Design of a Fast-cycling High-gradient Rotating Linac for Protontherapy	3642
	A. Degiovanni, U. Amaldi, D. Bergesio, C. Cuccagna, A. Lo Moro, P. Magagnin, P. Riboni, V. Rizzoglio TERA, Novara, Italy
	General interest has been shown over the last years for the development of single room facilities serving a population of about 2 million people for proton cancer therapy. Compact machines are needed to accelerate proton beams of few nanoamperes up to 230 MeV. In this framework the project TULIP (Turning LInac for Protontherapy), patented by TERA Foundation, foresees a linac mounted on a rotating gantry used as a booster for protons previously accelerated by a cyclotron. The linac is composed of modular units powered by independently controlled klystrons. The RF power transmission is made possible by high power rotating joints developed in collaboration with CLIC group. The final beam energy can be varied in steps of few MeV from pulse to pulse by amplitude and/or phase modulation of the klystron signals, making possible the implementation of active spot scanning technique with tumor multi-painting. The present paper provides the main characteristics of TULIP, describing the different choices for the linac design parameters together with the structural design of the supporting gantry and of the final beam line.
THPWA016	Design and Optimization of the Target in Electron Linear Accelerator	3663
	Q. Gao, H.B. Chen, J. Shi, H. Zha TUB, Beijing, People's Republic of China
	The target in electron linear accelerator plays an important role in the production of photon. Different materials and thickness of target have influence on dose rate. For 6MeV electron beam, this study gives the thickness of target for several materials in which the dose rate can be higher and drain electron can be lower. Then a X-ray target had been designed for 6MeV electron linac by FLUKA simulations. It can deliver 1000 cGy/min at 1 meter in front of the target if providing 6 MeV electron beam with 100uA current, which can achieve high-dose rate radiotherapy.
THPWA018	High Power Test of a C-band 6 MeV Standing-wave Linear Accelerator	3666
	J.H. Shao, H.B. Chen, Y.-C. Du, Q.X. Jin, J. Shi, H. Zha TUB, Beijing, People's Republic of China
	A C-band 6MeV standing-wave bi-periodic on-axis coupled linear accelerator has been developed at the accelerator laboratory of Tsinghua University [1,2]. In the recent high power RF test, the capture ratio, the energy spectrum, the spot size and the dose rate of this accelerator have been measured. With a 2.07-MW input power, the peak current is 130mA and the output spot root-mean-square diameter is about 0.8mm. The output kinetic energy is 6.0MeV with a spectrum FWHM of 7.5%. In this paper, the setup and detailed results of the high power RF test are presented.
THPWA030	Design and Prototype Test of C-band Standing-wave Accelerating Structure to Enhance RF Phase Focusing	3690
	H. Yang, M.-H. Cho, W. Namkung, S.-G. Shin POSTECH, Pohang, Kyungbuk, Republic of Korea S.H. Kim ANL, Argonne, USA J.-S. Oh NFRI, Daejon, Republic of Korea
	Funding: This research was financially supported by the MOTIV, KIAT and Dongnam Institute for Regional Program Evaluation through the Leading Industry Development for Economic Region A C-band standing-wave accelerator for X-ray and electron beam sources of medical radiotherapy is designed and being fabricated. The accelerator system is to be operated in two modes, using the X-ray and electron beams. Because of the energy loss in electron mode, the accelerator is capable of producing 6-MeV, 100-mA electron beams with peak 2-MW RF power, and 7.5-MeV, 20 mA electron beams with peak 2.5-MW RF power. The beam radius at the end of column was < 0.5 mm without focusing magnets in PARMELA simulations, because the bunching cells are designed to enhance the RF phase focusing. Each cavity in the bunching and normal cells was designed by the MWS code to maximize the effective shunt impedance with 3.8% inter-cell coupling in normal cells. The dimensions of normal cells were determined by the low power RF test of prototype cells with 5711.06-MHz resonant frequency and 3.5% inter-cell coupling. In this paper, we present details of the accelerator design and prototype test.
THPWA031	Raising the Generating Current in the VITA Neutron Source for BNCT	3693
	A.S. Kuznetsov, V.I. Aleynik, A.G. Bashkirtsev, D.A. Kasatov, A.N. Makarov, I.M. Schudlo, I.N. Sorokin, S.Yu. Taskaev, M.A. Tiunov BINP SB RAS, Novosibirsk, Russia
	Funding: The work was partially supported by the Ministry of Education and Science of the Russian Federation (contract № 14.518.11.7039). The Vacuum Insulated Tandem Accelerator (VITA) was developed in the Budker Institute of Nuclear Physics to produce epithermal neutrons for boron neutron capture therapy in the 7Li(p,n)7Be reaction. The parameters of the generated radiation allow us to carry out in vitro and in vivo investigations of BNCT. In present moment the modernization of the facility elements is carrying out to meet the parameters required for clinical usage. As the first step of the modernization the stripping target and electrode apertures were optimized. The experiments on fine beam injection were carried out as well as experiments on high current transportation. The output current in the range 1.5-2.5 mA with proton beam energy of 1 – 2 MeV was obtaned in the routine regimes of generation. In presented work the results of the experiments and possible way to rise the proton current higher then 3 mA level with energy 2 MeV are discussed. *S. Taskaev, et al. Vacuum-insulation Tandem Accelerator for Boron Neutron Capture Therapy. Proc. 2nd International Particle Accelerator Conference (IPAC-2011),2011, San Sebastian, Spain, p.3615-3617.
THPWA037	PIP: A Low Energy Recycling Non-scaling FFAG for Security and Medicine	3711
	R.J. Barlow, T.R. Edgecock University of Huddersfield, Huddersfield, United Kingdom C. Johnstone Fermilab, Batavia, USA H.L. Owen UMAN, Manchester, United Kingdom S.L. Sheehy STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
	PIP, the Producer of Interacting Protons, is a low energy (6-10 MeV) proton nsFFAG design that uses a simple 4-cell lattice. Low energy reactions involving the creation of specific nuclear states can be used for neutron production and for the manufacture of various medical isotopes. Unfortunately a beam rapidly loses energy in a target and falls below the resonant energy. A recycling ring with a thin internal target enables the particles that did not interact to be re-accelerated and used for subsequent cycles. The increase in emittance due to scattering in the target is partially countered by the re-acceleration, and accommodated by the large acceptance of the nsFFAG. The ring is essentially isochronous, the fields provide strong focussing so that losses are small, the components are simple, and it could be built at low cost with existing technology.
THPWA039	GEANT4 Target Simulations for Low Energy Medical Applications	3717
	N. Ratcliffe, R.J. Barlow, A. Bungau, C. Bungau, R. Cywinski University of Huddersfield, Huddersfield, United Kingdom
	The GEANT4 code offers an extensive set of hadronic models for various projectiles and energy ranges. These models include theoretical, parameterized and, for low energy neutrons, data driven models. Theoretical or semi-empirical models sometimes cannot reproduce experimental data at low energies(<100MeV), especially for low Z elements, and therefore recent GEANT4 developments included a new particle\hp package which uses evaluated nuclear databases for proton interactions below 200 MeV. These recent developments have been used to study target designs for low energy proton accelerators, as replacements of research reactors, for medical applications. Presented in this paper are results of benchmarking of these new models for a range of targets, from lithium neutron production targets to molybdenum isotope production targets, with experimental data. Also included is a discussion of the most promising target designs that have currently been studied.
THPWA048	New Generation X-band Linacs for Medical and Industrial Appplications	3741
	A.V. Mishin, S. Proskin RMX, North Andover, USA
	The proposed designs of the new X-band linear accelerators for industrial and medical applications are based on a well-known side-coupled RF structure. The immediate applications envisioned for the new linear accelerators are security screening and intraoperative radiotherapy (IORT). The new design has promising features and presents cost reduction potential for electron beam and X-ray systems used in medical, industrial, and security screening applications.
THPWA050	Beam Conditioning System for Laser-driven Hadron Therapy	3743
	K.E. Woods, S. Boucher, F.H. O'Shea RadiaBeam, Santa Monica, USA B.M. Hegelich The University of Texas at Austin, Austin, Texas, USA
	While the superior therapeutic efficacy of hadron therapy has been clearly demonstrated, its availability to cancer patients is limited by the cost and size of current systems. RadiaBeam Technologies, in collaboration with the UCLA Department of Radiation Oncology and the University of Texas at Austin, is proposing the utilization of innovative laser-driven ion acceleration (LDIA) technology for the development of a compact, inexpensive proton therapy system that can ultimately be adapted for the acceleration of carbon ions. At less than a third the price of the average proton therapy unit, the realization of this system would make hadron therapy a much more realistic option for hospitals and clinics worldwide. However, LDIA produces a beam with large divergence, wide energy spread with multiple ion species, and a significant background of electrons and X-rays. Thus, a major challenge for clinical implementation of LDIA is the development of a post-target beam conditioning system for collimation, focusing, energy selection, background shielding, and scanning. This paper will discuss the progress of our design of such a system and plans for future testing.