HIBISCUS: a new ion beam radio-frequency quadrupole cooler-buncher for high-precision experiments with exotic radioactive ions

HIBISCUS (Helium-Inflated Beam Improvement Setup that Cools and Undermines Spreads), a new radiofrequency quadrupole cooler-buncher device has been developed and commissioned offline at the Ion Guide Isotope Separator On-Line (IGISOL) facility in Jyväskylä in Finland, as an in-kind contribution for the Facility for Antiproton and Ion Research facility. HIBISCUS improves the ion optical properties of incident low-energy 6~keV beams with the option to have it ultimately extracted in temporally short bunches ($<1$~$\mu$s). This paper provides technical descriptions of its main characteristics, along with a set of optimum working parameters and performance in terms of transmission efficiency, longitudinal energy spread of the cooled ions and temporal width of the extracted bunches.