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2011 | 17 | 1 | 13-25

Article title

Measurement of Head Scatter Factor for Linear Accelerators using Indigenously Designed Columnar Mini Phantom


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A columnar mini phantom is designed as recommended by ESTRO to measure the Head Scatter Factor (Sc) for 6 MV beam of two linear accelerators. The measurement of Sc at different orientations of the chamber, parallel and perpendicular at 1.5 cm depth predicts the deviation of 2.05% and 1.9% for Elekta and Siemens linear accelerators respectively. The measurement of Sc at 1.5 cm is higher compared to 10 cm depth for both the linear accelerators suggesting the electron contamination at 1.5 cm depth. The effect of wedges on Sc yields a significant contribution of 3.5% and 5% for Siemens and Elekta linear accelerators respectively. The collimator exchange effect reveals the opening of upper jaw increases the Sc irrespective of the linear accelerator. The result emphasizes the need of Sc measurement at 10 cm. The presence of wedge influences the Sc value and the SSD has no influence on Sc. The measured Sc values are in good agreement with the published data.









Physical description


1 - 1 - 2011
7 - 2 - 2012


  • Medical Physics Division, Dr. Kamakshi Memorial Hospital, No:1, Radial Road, Pallikaranai, Chennai - 600 100. Tamil Nadu
  • Medical Physics Division, Dr. Kamakshi Memorial Hospital, No:1, Radial Road, Pallikaranai, Chennai - 600 100. Tamil Nadu
  • Nuclear and Medical Physics Division, School of Advanced Sciences, VIT University, Vellore - 632 014. Tamil Nadu


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