The superconducting heavy ion HELmholtz LInear ACcelerator (HELIAC) is designed to meet the needs of the Super Heavy Element (SHE) research and material science user programs at GSI in Darmstadt. The beam energy can be varied smoothly between 3.5 and 7.3 MeV/u, with an average current of up to 1 emA and a duty cycle of 100 %. Recently, the first cryomodule CM1, was fully commissioned and tested. CM1 comprises three Crossbar H-mode (CH)-type accelerator cavities, a CH-rebuncher, and two superconducting solenoid lenses. Following the commissioning of the cryogenic supply- and RF-systems, a successful beam test was conducted at the end of 2023. A helium ion beam was successfully accelerated to the design energy of 2.7 MeV/u. The beam energy could be varied continuously between 1.3 and 3.1 MeV/u without any significant particle losses being measured in the cryomodule. This contribution covers the construction and commissioning of the first HELIAC cryomodule and the results of the beam test campaign.

After dedicated machine upgrade measures at the GSI UNILAC, a high current beam campaign has been performed recently. The presented results were accomplished - among other things - with newly installed electrodes for the superlens (short RFQ-type matching section), working completely fault free. Beam experiments have been conducted with high intensity proton beam (1.2 mA), carbon (1 mA 12C6+) and nitrogen beam (5.4 mA 14N7+) dedicated for pion production. A record argon beam intensity of 28 mA (40Ar11) has been obtained at gas stripper section. A sufficiently high stripping efficiency of 35% applying a pulsed N2 gas stripper target could be realized. By achieving high-current performance for medium-heavy ions, a further step has been taken towards fulfilling the FAIR requirements for high-current operation. In this contribution the results of machine experiments are summarized, in particular the performance enhancement at the High Current Injector section (HSI).

The 50 years old GSI-UNILAC (Universal Linear Accelerator) as well as the heavy ion synchrotron SIS18 will serve as a high current heavy ion injector for the FAIR (Facility for Antiproton and Ion Research) synchrotron SIS100. The UNILAC together will provide for short and intense pulses. This contribution presents the results of the full performance high current uranium beam machine experiment campaign at UNILAC, conducted in the last three years. In order to determine the behavior of uranium beams, the transverse beam emittance at five selected measurement positions along the complete UNILAC have been measured for the first time in several machine investigation runs. A significant improvement in beam brilliance was achieved by using the pulsed hydrogen stripper at 1.4 MeV/u. It could be shown that extremely low horizontal emittances, i.e. very high brilliances, are achieved along the complete UNILAC up to the SIS injection. Besides high intense uranium beam with charge state 28+ also multi charge beam, comprising 27+, 28+, 29+ uranium ions, commonly recharged primarily to charge state 73+ using a carbon foil, were investigated and a record current of 3.6 emA has been achieved.

A crucial milestone towards the final expansion stage of the HELIAC (Helmholtz linear accelerator at HIM & GSI) is the commissioning of the first fully equipped cryomodule, the so-called Advanced Demonstrator. The cryomodule comprises three accelerating superconducting crossbar H-mode cavities, a buncher and two superconducting solenoids. For modelling the beam dynamics of the Advanced Demonstrator test setup, the actual 3D electromagnetic field distributions of the cavities and solenoids are used. The digital model was paired with beam-based measurements of the longitudinal and transverse beam density distribution to calculate the realistic beam propagation along the 20 m setup. The beam dynamics insights gained during the cryomodule commissioning are presented.

The superconducting heavy ion HELmholtz LInear ACcelerator (HELIAC) is designed to meet the needs of the Super Heavy Element (SHE) research and material science user programs at GSI in Darmstadt. The beam energy can be varied smoothly between 3.5 and 7.3 MeV/u, with an average current of up to 1 emA and a duty cycle of 100 %. Recently, the first cryomodule CM1, was fully commissioned and tested. CM1 comprises three Crossbar H-mode (CH)-type accelerator cavities, a CH-rebuncher, and two superconducting solenoid lenses. Following the commissioning of the cryogenic supply- and RF-systems, a successful beam test was conducted at the end of 2023. A helium ion beam was successfully accelerated to the design energy of 2.7 MeV/u. The beam energy could be varied continuously between 1.3 and 3.1 MeV/u without any significant particle losses being measured in the cryomodule. This contribution covers the construction and commissioning of the first HELIAC cryomodule and the results of the beam test campaign.