On 10 June 2026, just after 14:00, the IFMIF/EVEDA Project reached an important milestone with the start of warm conditioning of the LIPAc Superconducting Radio-Frequency Linac, now integrated into the beam line.

Warm conditioning is an essential preparation step performed at room temperature before operation at cryogenic temperature. During this phase, radio-frequency power is progressively injected into the RF power couplers, while the superconducting cavities are kept detuned. This process allows the couplers and associated RF systems to be gradually brought to their operating conditions under carefully monitoring. This activity began in line with the accelerated schedule presented at Project Committee #37 and marks the first RF injection into the one of the eight power couplers of the integrated SRF Linac. The initial operation progressed well, with this first coupler under conditioning behaving as expected.

During the first RF injections, the team monitored the cavity and coupler parameters through dedicated operator interfaces, including the RF power delivered to the coupler, the reflected power, the vacuum response and the photomultiplier signals. The observed vacuum activity and light signals are consistent with the expected conditioning behaviour, in particular considering that the couplers had been stored under nitrogen for several years after their initial conditioning before assembly.

SRF Linac area being prepared for warm conditioning
The SRF Linac and associated systems were prepared for the start of warm conditioning, following intensive coordination between the Project Team, CEA and QST teams.

Following these encouraging first results, the conditioning campaign is now continuing in automatic mode during the nights, with continuous monitoring provided by the QST contractor. This allows the conditioning process to progress efficiently while maintaining the required level of operational supervision.

The successful start of warm conditioning represents a significant step forward in the preparation of the forthcoming beam commissioning activities and confirms the strong progress being made by the IFMIF/EVEDA Project team.

A decisive step towards record light hadron beam performance and IFMIF-DONES validation

Europe and Japan have brought LIPAc to its full accelerator configuration in Rokkasho, Japan.
This milestone marks a decisive step for the IFMIF/EVEDA project and the future of fusion materials testing. With all major subsystems now installed, the 36-meters accelerator is ready to enter its next commissioning phase.

At its core, the SRF section aims at accelerating particles up to 9 MeV at 125 mA in continuous-wave operation. This highly demanding regime is essential to reduce the main technical risks for future fusion neutron source facilities such as IFMIF-DONES and A-FNS.

With assembly completed, the teams will now proceed with progressive commissioning, including RF conditioning, cryogenic operation and integrated tests. Warm conditioning is planned to start in June 2026 and beam operations are planned to start by March 2027, first with protons and then with deuterons. LIPAc now enters a decisive phase to turn years of European-Japanese collaboration into demonstrated accelerator capability.