Keyword: synchrotron
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PO13 Longitudinal Beam Motion in the KEK Digital Accelerator: Tracking Simulation and Experimental Results space-charge, simulation, induction, acceleration 83
  • X. Liu
    Department of Energy Sciences, Tokyo Institute of Technology, Yokohama, Japan
  • T. Adachi
    Sokendai, Ibaraki, Japan
  • S. Harada
    Tokyo City University, Tokyo, Japan
  • T. Iwashita
    KEK, Ibaraki, Japan
  • K. Takayama, T. Yoshimoto
    TIT, Yokohama, Japan
  Beam commissioning in the KEK Digital Accelerator*, which is a small scale induction synchrotron (IS), has been conducted since the middle of 2011. Longitudinal beam motion in the induction synchrotron, which utilizes induction cells (IC) for acceleration and confinement, is characterized as barrier bucket acceleration. . These ICs are driven by the switching power supply (SPS). Pulse voltage is fully managed by the gate control for solid-state switching elements in the SPS, where FPGAs and DSPs take a key role**. A tracking code has been developed to understand the longitudinal motion affected by longitudinal space charge forces, under programmed settings of confinement and acceleration voltage. This code, where the trigger control scenario is fully implemented, calculates temporal evolution of momentum and phase of macro-particles. The simulation result has well reproduced beam commissioning results, such as bunch squeezing experiment and barrier bucket acceleration. In addition, the code is going to be applied to explain the rapid growth of micro-bunch structure in the injected ion bunch.
* T. Iwashita et al., “KEK Digital Accelerator” , Phys. Rev. ST-AB 14, 071301 (2011). And K.Takayama et al., in this conference.
** S.Harada, Ms. Thesis (TCU) (2011).
PO14 Feedback of Slow Extraction in CSRm quadrupole, extraction, feedback, emittance 89
  • J. Shi, W.P. Chai, J. Li, J.W. Xia, J.C. Yang, Y.J. Yuan
    IMP, Lanzhou, People's Republic of China
  The transverse tune of the beam in the synchrotron will fluctuate due to the quadrupole current ripple, which lead the spill ripple through the variation of the separatrices area. In order to reduce the ripple of the spill, a pair of fast response quadrupole (FQ) is adopted to compensate the tune ripple caused by other quadrupoles. After using the FQ feedback, the amplitude of the spill ripple within 800Hz has been reduced to 1/10 times from the normal mode. This method will be used in the HITFiL (Heavy Ion Therapy Facility in Lanzhou).  
TUB04 LINAC Experience In The First Two Years of Operation @ CNAO (Centro Nazionale Adroterapia Oncologica) linac, rfq, proton, injection 129
  • S. Vitulli, E. Vacchieri
    CNAO Foundation, Milan, Italy
  • A. Reiter, B. Schlitt
    GSI, Darmstadt, Germany
  CNAO is the first medical accelerator facility for deep hadrontherapy with C6+ and H3+ in Italy. The LINAC device at CNAO include a RFQ structure accelerating up to 400 keV/u and an IH structure works up to 7 MeV/u. Such LINAC works as injector in a 78 m circumference synchrotron where the beam reaches up to 400 MeV/u. The LINAC commissioning was performed during 2009 and from beginning of 2011, it entered into routine and continuous operation. First patient was treated in September 2011. The principal LINAC parameters are daily monitored, like output energy (by means of online not destructive ToF measurements), cavities voltage, cavities RF forward power, beam current transmission. No major faults were observed in the first two years of operation. LINAC beam is stable within an error of ±0.02 MeV/u. The relation between LINAC extraction and synchrotron injection is under investigation. This paper summarizes the monitoring issues (i.e. reproducibility of settings and beam parameters as well as long term stability measures) on the CNAO LINAC during daily patient treatments and outlines the measurements performed in the initial commissioning compared within actual status.  
WEA01 Advanced Accelerator Technology Aspects for Hadron Therapy proton, ion, cyclotron, extraction 156
  • L. Falbo
    CNAO Foundation, Milan, Italy
  Nowadays cancer can be considered as one of the wide spread diseases all around the world. Radiotherapy is the clinical technique used in 40% of cancer treatments: nowadays about 40% of the 18000 particle accelerators running in the world are devoted to radiotherapy. Classical radiotherapy employs photons and electrons that damage not only the diseased cells but also the healthy ones. Hadrontherapy is a high-precision radiotherapy exploiting the depth-dose deposition characteristics of the hadron particles. The realization of machines for hadrontherapy is more challenging than for standard radiotherapy: while most of hospitals have a device for classical radiotherapy, the hadrontherapy needs a dedicated building with the needed technology for the hadron acceleration. The first hadrontherapy treatments have been performed in particle physics research centers clinically adapted; nowadays there are dedicated facilities designed and built as hadrontherapy centers. This paper will give an overview on the existing hadrontherapy centers presenting the technologic background that is at the basis of the hadrontherapy world.  
slides icon Slides WEA01 [4.493 MB]