Determination of the k correction factors for several detectors used with an 800 MU/min CyberKnife® system equipped with fixed collimators and study of detector characteristics on their response in small photon beams using a Monte Carlo method

In a previous work, output ratio (ORdet) measurements were performed for the 800 MU/min CyberKnife® at the Oscar Lambret Center (COL, France) using several commercially available detectors (Sun Nuclear EDGE, IBA SFD, PTW 60016, PTW 60017, PTW 31014 and PTW 60003) designed for small beams as well as using two passive dosimeters (EBT2 radiochromic film and Harshaw micro-LiF TLD-700). The primary aim of this work was to determine by Monte Carlo calculations the output factor in water (OFMC,w) and to identify the detectors best suited to the measurements of output factors (OF) in small beams. The secondary aim was to calculate the correction factors; and also, to determine the detector response in small beams using Monte Carlo simulation.