The Linear IFMIF Prototype Accelerator, LIPAc, is being commissioned aiming at validating the RFQ up to 5 MeV beam acceleration. Eventually, the nominal beam of 5 MeV–125 mA in 1 ms length and 1 Hz rate pulsed mode was achieved in 2019. The beam operation has been resumed since July 2023 after a long maintenance including recovery from unexpected problems in the RFQ-RF system. This new phase aims at the commissioning of the full configuration except SRF LINAC, which is replaced by a temporary beam transport line. Focusing on the RFQ behavior, it will be interesting to operate it at higher duty, especially for longer pulses. Furthermore, a beam simulation study suggested that the beam extracted from the RFQ includes considerable momentum halo when the vane voltage reduces by more than 5 %, with a slight decrease of the mean energy. It can be a potential source of a quench like the mismatched beam in the cryomodule. This could be studied by measuring the energy from the Time-of-Flight among multiple BPMs while monitoring beam loss around the dipole, where momentum halo should be lost. During the beam commissioning phase, we studied them by scanning the RFQ voltage.
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