Experimental Evaluation of Sub-Sampling IQ Detection for Low-Level RF Control in Particle Accelerator Systems.

The low-level radio frequency (LLRF) control system is one of the fundamental parts of a particle accelerator, ensuring the stability of the electro-magnetic (EM) field inside the resonant cavities. It leverages on the precise measurement of the field by in-phase/quadrature (IQ) detection of an RF probe signal from the cavities, usually performed using analogue downconversion. This approach requires a local oscillator (LO) and is subject to hardware non-idealities like mixer nonlinearity and long-term temperature drifts.

Practical aspects of using beta-delayed gamma emission for copper ore analysis on a running belt conveyor.

In this study, we investigated the feasibility of copper ore analysis on a running belt conveyor by measuring the delayed positron annihilation quanta based on the beta-decay of Cu, which was previously activated by a D-T, 14 MeV neutron generator. We constructed a model of a belt conveyor that measured 10 m in length to test this method. Our measurements demonstrated the feasibility of the method but practical constraints imposed by user demands and the industrial environment would make the design impractical and cost inefficient.

Electron bunch timing with femtosecond precision in a superconducting free-electron laser.

High-gain free-electron lasers (FELs) are capable of generating femtosecond x-ray pulses with peak brilliances many orders of magnitude higher than at other existing x-ray sources. In order to fully exploit the opportunities offered by these femtosecond light pulses in time-resolved experiments, an unprecedented synchronization accuracy is required. In this Letter, we distributed the pulse train of a mode-locked fiber laser with femtosecond stability to different locations in the linear accelerator of the soft x-ray FEL FLASH.