The Study of Dosimetric Characteristics of the XHA600D Medical Linear Accelerator Based on a Monte Carlo Code

Table 7

The measured and calculated data of flatness and symmetry of FF beams. (The uncertainties of simulated flatness in FF mode of 4 × 4, 6 × 6, 8 × 8, 10 × 10, 15 × 15, 20 × 20, 25 × 25, 30 × 30 cm² fields were as follows: 0.4%, 0.6%, 0.7%, 0.9%, 1.2%, 1.4%, 1.6%, 2% (k = 2). The uncertainties of simulated symmetry in FF mode of 4 × 4, 6 × 6, 8 × 8, 10 × 10, 15 × 15, 20 × 20, 25 × 25, 30 × 30 cm² fields were as follows: 0.3%, 0.4%, 0.5%, 0.6%, 0.8%, 0.9%, 1%, 1.2% (k = 2).).

Field size (cm^2)	Flatness (%)		Symmetry (%)
	Simulated (%)	Measured (%)	Simulated (%)	Measured (%)
4 × 4	1.77	2.66	0.0421	0.611
6 × 6	1.82	2.26	0.0453	0.166
8 × 8	1.57	1.80	0.160	0.143
10 × 10	1.49	1.66	0.100	0.127
15 × 15	2.02	1.95	0.110	0.00298
20 × 20	2.16	1.47	0.130	0.0303
25 × 25	2.25	1.66	0.304	0.598
30 × 30	2.33	1.57	0.208	0.626