Monte Carlo calculation of beam quality correction for solid‐state detectors and phantom scatter correction at 137 Cs energy

Beam quality correction k Q Q 0  ( r ) , which reflects the absorbed energy dependence of the detector, is calculated for solid‐state detector materials diamond, LiF, Li 2B 4O 7 , andAl 2O 3for the137 Cs RTR brachytherapy source using the Monte Carlo‐based EGSnrc code system. The study also includes calculation of detector‐specific phantom scatter corrections k p h a n ( r ) for solid phantoms such as PMMA, polystyrene, RW1, solid water, virtual water, and plastic water. Above corrections are calculated as a function of distance r along the transverse axis of the source. k Q Q 0  ( r ) is about unity for the Li 2B 4O 7detector. LiF detector shows a gradual decrease in k Q Q 0  ( r ) with r (decrease is about 2% over the distance range of 1‐15 cm). Diamond detector shows a gradual increase in k Q Q 0  ( r ) with r (about 3% larger than unity at 15 cm). In the case ofAl 2O 3detector, k Q Q 0  ( r ) decreases with r steeply (about 14% over the distance range of 1‐15 cm). The study shows that some solid‐state detectors demonstrate distance‐dependent k p h a n ( r ) values, but the degree of deviation from unity depends on the type of solid phantom and the detector. PACS number: 87.10.Rt, 87.53.Bn, 87.53.Jw, 87.56.Bg