Development of a silicon detector monitor for the HIE-ISOLDE superconducting upgrade of the REX-ISOLDE heavy-ion linac

A silicon detector monitor has been developed and tested in the framework of the beam diagnostics development program for the HIE-ISOLDE superconducting upgrade of the REX-ISOLDE heavy-ion linac at CERN. The monitor is intended for beam energy and timing measurements aimed at the phase tuning of the superconducting cavities. Tests were performed with a stable ion beam, composed of carbon, oxygen and neon ions accelerated to energies from 300 keV/uu to 2.82 MeV/uu. The energy measurements performed allowed for beam spectroscopy and ion identification with a resolution of 1.4%–0.5% rms in the measured energy range. The achieved resolution is suited for a fast phase tuning of the cavities, which was demonstrated with the third REX 7-gap resonator. The time structure of the beam, characterised by a bunch period of 9.87 ns, was measured with a resolution better than 200 ps rms. This paper describes the results from all these tests and provides details of the detector set-up.

► New beam monitor developed for the superconducting HIE-ISOLDE linac. ► It performs longitudinal beam measurements aimed at fast cavity phase tuning. ► First monitor tests performed at REX-ISOLDE. ► Beam energy and time profile acquired with high resolution. ► Phase-up procedure demonstrated with energy and Time-of-Flight measurements.