HIAF project is a major national science and technology infrastructure project in China which aims at providing high intensity ion bunches at the repetition frequency of 3 Hz for scientific research or industry applications from international users. In the complicated manipulations that generate those high intensity beams, diverse high intensity effects, especially space charge effects, collective instabilities, dynamical vacuum effects, etc., and their coupling effects have many detrimental impacts on the final beam intensity and quality. Several beam dynamics simulation platforms are developed, and the theory or simulation studies are performed to build corresponding solutions which are already installed in the HIAF, including resonance correction sextupole magnets, digital feedback systems, collimators for ions whose charge states are changed by residual gas, and so on. The beam commissioning of the whole HIAF facility will be performed soon, and day one experiments will also be conducted at the end of this year. All compensation schemes of high intensity effects will be employed gradually in the future beam commissioning to drive continuous performance improvement of the HIAF.

Resonance crossing, jointly determined by a large space-charge tune spread and magnetic field errors, is the main cause of beam loss and emittance growth in HIAF-BRing. For weak beams, the classical theory based on the resonance driving terms (RDTs) allows a perfect resonance compensation through precisely pre-known nominal TWISS parameters. As the space-charge gets intensified, however, the phase shift and beam envelope of particle’s betatron oscillations are significantly modulated, which may lead to an inaccurate estimation on RDTs and hence an ineffective compensation. In this talk, a comparison will be made on the efficiency of a simultaneous compensation of multiple third-order resonances for two cases, (i) using nominal optics and (ii) considering the space-charge modulation on TWISS parameters, by numerical simulations. Besides, a procedure will be outlined for resonance compensation experiments in BRing, and a discussion will be given on how to apply the space-charge modulated TWISS in practical situations.