The STI group has a broad expertise on the interaction of beams with matter and applies its know-how to a large spectrum of activities including particle production, beam intercepting devices, studies on beam-matter interaction and nuclear engineering.

The group is in charge of the technical coordination of the ISOLDE facility. It ensures the regular production of targets for the ISOLDE physics program. This includes the production of new radioactive ion beams through a target and ion source development program, development of beam manipulation devices for both on-line and off-line test benches, responsibility of target stations and Class A type laboratories and the technical coordination of the ISOLDE facility. The MEDICIS (Medical Isotopes Collected from ISOLDE) facility is also part of the group’s activities. It aims at producing a wide range of radioisotopes for biological research.

In addition, the STI group’s astute knowledge of laser technology is applied to the development of ionisation techniques as well as spectroscopy studies in collaboration with the physics community. Thanks to this expertise, the group is also in charge of the development of photoinjectors of CLIC/CLEAR and the polarised electron and positron sources of the AWAKE experiment.

The group is responsible for the design, construction, operation and maintenance of all intercepting devices across the CERN complex, including studies related to crystal-based beam manipulations in collaboration with the UA9 experiment. Beam intercepting devices include the spallation neutron target of the n_TOF facility, the antiproton production target, the primary targets for the North and East Halls, all beam collimators, dumps and absorbers of the injector complex and the LHC. Material studies, design and assembly are all part of the key nuclear engineering competencies of the group.

The group collaborates in developing, disseminating and supporting the FLUKA code, a fully integrated Monte Carlo simulation package for the interaction and transport of particles and nuclei in matter. It provides formal training and support to its users in the accelerator community both at CERN and worldwide.

STI is also in charge of executing – by means of the FLUKA code – beam-machine interaction studies for a variety of different applications across the CERN Departments and for medical applications.
The group also hosts the Radiation to Electronics Project and is responsible for the operation of the n_TOF facility (target and experiments).