On the capabilities of conventional x‐ray tubes to deliver ultra‐high (FLASH) dose rates

Purpose By means of Monte Carlo (MC) simulations and indirect measurements, we have evaluated the maximum dose rates achievable with conventional x‐ray tubes and related them to FLASH therapy dose rates of >40 Gy/s. Methods Monte Carlo models of two 160 kV x‐ray tubes, the 3‐kW MXR‐160/22 and the 6‐kW MXR‐165, were built in the EGSnrc/BEAMnrc code. The dose rate in a water phantom placed against the x‐ray tube surface, located at 3.7 and 3.5...