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Abstract Heavy ion medical machine (HIMM) is the first Chinese heavy ion accelerator facility developed for cancer therapy. After commissioning, the slow extraction efficiency reached nearly 90% for all energies from 120 to 400 MeV/u. The spill duty factor exceeded 90% at a sample rate of 10 kHz. This paper reports the results of the HIMM's slow extraction commissioning. [ABSTRACT FROM AUTHOR]

To simulate collective instabilities during the complicated beam manipulation in the BRing (Booster Ring) of HIAF (High Intensity heavy-ion Accelerator Facility) or other high intensity accelerators, a code, named CISP (Simulation Platform for Collective Instabilities), is designed and constructed in China’s IMP (Institute of Modern Physics). The CISP is a scalable multi-macroparticle simulation platform that can perform longitudinal and transverse tracking when chromaticity, space charge effect, nonlinear magnets and wakes are included. And due to its well object-oriented design, the CISP is also a basic platform used to develop many other applications (like feedback). Several simulations, completed by the CISP in this paper, agree with analytical results very well, which shows that the CISP is fully functional now and it is a powerful platform for the further collective instability research in the BRing or other accelerators. In the future, the CISP can also be extended easily into a physics control system for HIAF or other facilities. [ABSTRACT FROM AUTHOR]

The 300 MeV proton and heavy ion accelerator complex, which is the key part of SESRI (Space Environment Simulation and Research Infrastructure) project, is currently under construction in China. It comprises an 18 GHz high charge-state ion source, a 108.48 MHz cascaded linac injector consisting of a four-rod RFQ and three interdigital H-mode drift tube linacs, a compact synchrotron, and three irradiation terminals. The extensive ion species from proton to 209Bi 32 + will be injected into the synchrotron using multi-turn injection method. The third-order resonance and RF-knockout extraction scheme is adopted to provide quasi-continuous spill for irradiation experiments. The general design of the accelerator complex and simulation results are discussed in this paper. [ABSTRACT FROM AUTHOR]

The High Intensity heavy ion Accelerator Facility (HIAF) is a new accelerator complex under design at the Institute of Modern Physics (IMP). The facility is aiming at the production of high intensity heavy ion beams for a wide range of experiments in high energy density physics, nuclear physics, atomic physics and other applications. It consists of a superconducting electron-cyclotron-resonance ion source and an intense proton ion source, a linear accelerator, a 34 Tm booster synchrotron ring, a 43 Tm multifunction compression synchrotron ring, a 13 Tm high precision spectrometer ring and several experimental terminals. A magnetized electron cooling device is supposed to be used in the booster ring for decreasing the transverse emittance of injected beams. The conceptual design and main parameters of this cooler are presented in this paper. [ABSTRACT FROM AUTHOR]

Abstract The dynamic vacuum effect induced by the charge exchange beam loss will seriously limit the ion intensity and beam lifetime in the Booster Ring (BRing) of the High-Intensity Heavy Ion Accelerator Facility (HIAF). A dedicated collimation system has been designed to decrease the ion-induced gas desorption to suppress the dynamic vacuum effect. In order to reach 100% collimation efficiency, the optics lattice of BRing has been changed from original FODO to DBA structure. The distance between dipole and quadrupole in each lattice cell of BRing was optimized to maintain the high collimation efficiency. The hardware structure of the collimator was designed based on the simulation result and mechanical instrument control principle in the UHV vacuum system. The vacuum chamber and pump installment with collimators has been designed. A prototype collimator with vacuum chamber has been installed on the beamline to measure the gas desorption with beam and verify the availability and reliability of mechanical design. This prototype collimator has passed factory field tests and used to measure the gas desorption rate with the beam 112Sn 26 + at the energy 150 MeV/u successfully. [ABSTRACT FROM AUTHOR]

HIAF-BRing, a new multipurpose accelerator facility of the High Intensity heavy-ion Accelerator Facility project, requires an extremely high vacuum lower than 10 −11 mbar to fulfill the requirements of radioactive beam physics and high energy density physics. To achieve the required process pressure, the bench-marked codes of VAKTRAK and Molflow+ are used to simulate the pressure profiles of the BRing system. In order to ensure the accuracy of the implementation of VAKTRAK, the computational results are verified by measured pressure data and compared with a new simulation code BOLIDE on the current synchrotron CSRm. Since the verification of VAKTRAK has been done, the pressure profiles of the BRing are calculated with different parameters such as conductance, out-gassing rates and pumping speeds. According to the computational results, the optimal parameters are selected to achieve the required pressure for the BRing. [ABSTRACT FROM AUTHOR]

The High energy FRagment Separator (HFRS), a new generation in-flight radioactive separator, is under construction at the high-intensity Heavy Ion Accelerator Facility (HIAF) in China. To further optimize the separator performance and consider the manufacturing technology, the specifications of some magnetic elements of the HFRS separator have been modified from the original design reported earlier, and prototypes of partial magnetic elements have been fabricated and tested. In this paper, updates of magnetic parameters, test results of prototypes, and development of ion-optical calculation are presented. The high-order correction of aberrations is demonstrated. The performance of the separator is studied using fission reactions and fragmentation reactions of relativistic 238U projectiles. This work will guide the forthcoming experiments in the future HFRS separator. [ABSTRACT FROM AUTHOR]

As many diverse accelerator facilities are designed, constructed and operated by IMP (Institute of Modern Physics, Chinese Academy of Sciences), the existing physics control system cannot cover all requirements of these facilities. In order to save the construction time, improve the commissioning efficiency, simplify the operation and reach higher beam intensity and better beam quality, a new physics control system, PACS (Physics-oriented Accelerator Control System), is proposed, designed and implemented in the IMP. With the control layer in three layers, i.e. application layer, physics layer and control layer, the PACS is protocol neutral and can be deployed to all accelerator facilities in the IMP without massive reprogramming. The physics layer encapsulates all physics control processes, including device-level physics and system-level physics, into highly usable interfaces, which makes the development of the application layer and the customized applications simpler, more robust and efficient. Due to the OOP (Object-oriented Programming) technology used in this layer and specific designs, the PACS is highly scalable and can keep pace with the rapidly changing hardware and software. As the application layer is built upon the physics layer interfaces, no matter what is updated in the physics layer, the applications remain unchanged. Many new physics control processes can be tested and implemented in the physics layer by the developers or the users without influencing the operation of these facilities. Now, a version of PACS for miniature facilities is implemented and tested in the CSR, a heavy ion accelerator facility for scientific research in the IMP. It meets the expected goals and provides a solid base for following versions. In the future, the PACS will become a general-purpose physics control system for all heavy ion accelerator facilities. [ABSTRACT FROM AUTHOR]

A new project, High Intensity heavy ion Accelerator Facility (HIAF), is currently being under design and construction in China. HIAF will provide beams of stable and unstable heavy ions with high energies, high intensities and high quality. An overview of new opportunities for atomic physics using highly charged ions and radioactive heavy ions at HIAF is given. [ABSTRACT FROM AUTHOR]