“…For medical use, a lowenergy package can be included to get more precise physical processes in the low-keV energy range needed for intraoperative radiation therapy (Gallina et al 2002 ). The code was verifi ed for medical applications in external and internal radiotherapy (Carrier et al 2004 ;Milhoretto et al 2010 ). In order to simulate the XRS 4, the geometry had to be implemented with a submillimetre accuracy and materials had to be defi ned by their elemental compositions (Yanch and Harte 1996 ).…”