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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]

BRing is the booster ring of the HIAF project in which the beam intensity is designed up to 1.0 × 1011 ppp (238U34+). In order to reach the required intensities, an efficient injection scheme is crucial and the beam loss during injection must not exceed the limits defined by machine protection and dynamic vacuum requirements. An injection scheme called two-plane painting multiturn injection is consequently proposed, which exploits both the horizontal and vertical acceptance of the BRing by a tilted electrostatic septum. The influence of the space charge on the injection process is important for the two-plane multiturn injection scheme which should provide the required intensity with a minimal beam loss. The impact of the space charge on the efficiency of the injection process is investigated using a modified ORBIT code. In order to achieve lower beam loss, the particle swarm algorithm is proposed for a detailed injection optimization with space charge effect. Detailed studies on the two-plane painting multiturn injection scheme and the dependence on the lattice tune, the injected beam current, and the injected beam emittance are also presented. The results provide an important guideline for the design optimization of the injection system for the HIAF-BRing. [ABSTRACT FROM AUTHOR]

H igh I ntensity heavy-ion A ccelerator F acility (HIAF) project is being constructed by the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS). An in-flight H igh energy FR agment S eparator (HFRS) at HIAF was designed to study the properties of rare isotopes far away from the line of beta stability and their involved nuclear reactions of astrophysics interests. HFRS is a two-stage magnetic system which consists of Pre-Separator and Main-Separator. The maximum magnetic rigidity of 25 Tm was designed in particular for experiments with very neutron-rich rare isotopes beams and studies of hypernuclei and Δ-resonances in exotic nuclei. A dispersive mode and an achromatic mode were designed for different experimental requirements. The HFRS device can be used to separate and purify the rare isotopes produced by the projectile fragmentation of all primary beams up to Uranium or by the projectile fission of Uranium ions via Bρ-ΔE-Bρ method. The detailed HFRS ion-optical design including the first order and the higher order, and the magnet specification were presented in this paper. [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]

The construction of the high-intensity heavy-ion accelerator facility (HIAF) Yang et al. (2013) [1] at the Institute of Modern Physics, Chinese Academy of Science (IMP, CAS), has begun recently in Huizhou, Guangdong province, China. One of the devices of the HIAF is the Spectrometer Ring (SRing). Designed with two magnetic alloy (MA) loaded cavities to decelerate the heavy-ion beams, such as a 238U + 92 beam from 800 to 30 MeV/u, the SRing will serve as a multi-functional experimental storage ring. The MA cavity design works in the frequency range of 1.006-0.503 MHz with a maximum voltage of 50 kV and peak power of 220 kW. This study describes the variable-harmonic RF deceleration cavity design and a performance test of Chinese MA cores. [ABSTRACT FROM AUTHOR]

HIAF-BRing, the main synchrotron accelerator of the High Intensity Heavy-Ion Accelerator Facility, requires an average pressure lower than 1 × 10−9 Pa and the magnetic field increase rate no less than 12 T/s to fulfill radioactive beam physics and high energy density physics experiments. To reduce the eddy current effect and the gap size of dipoles compared to the thin-wall stainless steel vacuum chamber with reinforced ribs, a new design of ceramic-lined vacuum chamber with wall thickness 0.3 mm has been proposed by IMP. In order to effectively reduce the beam impedance and the desorption rate of ceramic materials, Au coating on ceramic (Yttria stabilized zirconia) by magnetron sputtering has been carried out. The adhesive force of Au film is 28.1 MPa measured by scratch test while the crystalline size of Au particle is in the range of 15.7–21.4 nm by X-ray diffraction (XRD). The longitudinal impedances of four types of round-ring-lined 0.6-m-long straight stainless-steel tubes and the ultimate pressure of the new designed vacuum chamber (uncoated vs Au-coated) have been measured to verify the feasibility of this method. • A new design of ceramic-lined vacuum chamber with wall thickness 0.3 mm has been proposed to reduce the eddy current effect and the gap size of dipoles, where the ceramic rings are Au-coated and a prototype has been designed and manufactured to test the concept. The ceramic ring is made by yttrium stabilized zirconia, which has very good mechanical strength and toughness. •Compared to the thin-walled stainless steel vacuum chamber with reinforced ribs, the gap size of the dipole decreases significantly and therefore the magnets manufacturing and operating cost reduce accordingly. •In order to reduce the beam impedance and the desorption rate of the ceramic surface, the ceramic rings have been coated with a 1 μm Au film. The Au coating has been characterized by several surface analysis technologies. Film quality proved to be good and adhesion was tested to be 28.1 MPa. [ABSTRACT FROM AUTHOR]