Raspberry Pi cameras (single board CMOS cameras) have already been successfully implemented for ion beam characterization at IAP Frankfurt and are now also being used to investigate multipacting during cavity conditioning. Multipacting appears caused by resonant secondary electron emission. For the standalone rf conditioning of the FRANZ (Frankfurt Neutron Source) RFQ (Radio-Frequency Quadrupole) and the IH-DTL (Interdigital H-mode Drift-Tube-Linac), these cameras were installed both inside and outside the vacuum to detect multipacting and other cavity glowing effects. The occurrence of multipacting at specific power levels within the cavities can be confirmed by simulations. In addition, the observed multipacting is characterized through spectrometer measurements.

The Frankfurt Neutron Source (FRANZ) at the Institute for Applied Physics in Frankfurt (IAP) is advancing toward the commissioning of proton beams up to 2 MeV. To support beam tuning behind the RFQ–IH acceleration chain, a dedicated diagnostics section is being installed downstream of the IH structure. The setup focuses on transverse beam characterization using scintillation screens combined with radiation-tolerant camera systems, enabling multi-angle (two-view) imaging of the proton beam under various beam-current and RF settings. Additional instruments include phase probes for energy and RF-phase monitoring, as well as a Faraday cup for current measurements. The camera-based diagnostics are designed to provide reliable visual feedback during early commissioning, particularly in an environment with limited access and the radiation levels typical for this region of the accelerator. This contribution presents the concept, implementation approach, and intended diagnostic capabilities of the camera-driven setup as FRANZ prepares for subsequent steps toward routine 2 MeV operation and the following delivery of the proton beam onto the lithium target for the first neutron production campaigns.

Raspberry Pi cameras (single board CMOS cameras) have already been successfully implemented for ion beam characterization at IAP Frankfurt and are now also being used to investigate multipacting during cavity conditioning. Multipacting appears caused by resonant secondary electron emission. For the standalone rf conditioning of the FRANZ (Frankfurt Neutron Source) RFQ (Radio-Frequency Quadrupole) and the IH-DTL (Interdigital H-mode Drift-Tube-Linac), these cameras were installed both inside and outside the vacuum to detect multipacting and other cavity glowing effects. The occurrence of multipacting at specific power levels within the cavities can be confirmed by simulations. In addition, the observed multipacting is characterized through spectrometer measurements.

We present results from a 1.4 MeV proton beam test of the first IH-Type linac structure additively manufactured (AM) from pure copper. The cavity has been tested up to 25 kW at a duty cycle of 2 %, which corresponds to a cavity voltage of 1 MV with peak fields at the drift tubes reaching up to 68 MV/m without RF breakdown at full power. A 1.4 MeV proton beam from a Van de Graaff accelerator has been accelerated up to 2.2 MeV, demonstrating the effective acceleration voltage of 0.83 MV at full power. These high power beam tests show performance en par with conventionally manufactured H-mode structures, paving the way for future linac structures benefiting from the advantages of additive manufacturing.

The Frankfurt Neutron Source FRANZ is a compact-accelerator driven neutron source based on the $^7Li(p,n)^7Be$ reaction using a 2 MeV proton beam. Following successful stand-alone RF conditioning of the IH-DTL up to 10 kW cw, the coupled RFQ-IH-DTL cavity was assembled, tuned and conditioned up to 200 kW. First beam experiments have been performed, demonstrating proton acceleration to 2 MeV. We report on the high-power conditioning, coupling and llrf tuning procedure, as well as initial beam commissioning results.