Transverse and longitudinal beam diagnostics and characterizations at IUAC-high current injector

The High Current Injector features normal-conducting RF Linac structures intended to accelerate various ion species with a mass-to-charge ratio of up to 6, achieving a maximum output energy of 1.8 MeV/u. It can deliver an intense analyzed beam up to 100pnA at the target. To preserve the beam quality at the target and to improve the performance of RF cavities and beam transmission, both destructive and non-destructive, fast and precise transverse and longitudinal beam diagnostics (including FFCs and CPOs for phase space and ToF measurements) are deployed in LEBT, MEBT and HEBT section of HCI. The beam energy was validated through the existing Surface Barrier Detector measurement setup. Recently, during 20Ne9+ beam test, we observed a notable energy spread of approximately 1%, which led to pronounced debunching and a complete loss of the necessary signal component in the downstream BPMs. To mitigate the energy spread, slits have been installed at the image plane of the fourth achromatic bending magnets, and it was observed that optimally adjusting the slits can reduce the spread by over fifty percent. This paper will present the latest measurements, challenges and future plans.