This manuscript presents characteristic dosimetry measurements for the 25 MV X-ray beam from the Varian Associates Clinac® 35 linear accelerator. The quality of the beam is expressed by its attenuation as a narrow beam in lead. Percentage depth dose tables are given as a function of field size for square fields. Tissue-phantom ratios are tabulated for square field sizes. A study of the variation of the dose in the buildup region demonstrates that surface dose and the depth of maximum dose is a strong function of the field size. Other beam parameters measured and discussed include field flatness and symmetry, penumbra, and applicability of inverse square law.
|Number of pages||7|
|Journal||International journal of radiation oncology, biology, physics|
|State||Published - Jan 1 1978|
- Linear accelerator
- Measurement techniques