Design and performance of the calorimeter for the FOOT experiment.

Hadrontherapy is a highly effective method for treating deep-seated tumours. However, the lack of information about cross-sections for fragments produced by beam-tissue nuclear interactions limits the precision of clinical treatment planning systems. The FOOT Collaboration is building a detector optimized for the identification of heavy fragments in a reverse-kinematics configuration, through the measurement of their momentum, energy and time of flight. The energy will be measured with a calorimeter composed by 300 BGO crystals coupled with SiPMs which will allow a compact design. Design and performance of the calorimeter tested at the facilities of CNAO and GSI will be discussed.