Table 1.

Settings of the collimator jaw position according to the applicator and the nominal electron beam energy. All field sizes are defined at $\text{SSD}=100\hspace{0.17em}\text{cm}$. ${\mathrm{R}}_{100},{\mathrm{R}}_{50}$, and ${\mathrm{R}}_{\mathrm{P}}$ values are specific for each electron beam energy

				Applicator Field Size
				$6\times 6$ a	($c{m}^2$) $10\times 10$	$20\times 20$
Energy (MeV)	R100 (cm)	R50 (cm)	RP (cm)	Collimator Jaw Settings (cm2)
Siemens Primus KD2
6	1.40	2.45	3.05	$16\times 16$	$19\times 19$	$27\times 27$
9	2.10	3.55	4.36	$16\times 16$	$19\times 19$	$27\times 27$
12	2.90	4.79	5.83	$16\times 16$	$19\times 19$	$27\times 27$
18	3.50	7.57	9.12	$16\times 16$	$19\times 19$	$27\times 27$
Varian 2300C/D
6	1.34	2.37	3.00	$20\times 20$	$20\times 20$	$25\times 25$
9	2.15	3.60	4.39	$20\times 20$	$20\times 20$	$25\times 25$
12	2.88	5.02	6.01	$11\times 11$	$14\times 14$	$25\times 25$
18	3.45	7.64	9.10	$11\times 11$	$14\times 14$	$22\times 22$
Siemens Oncor
6	1.40	2.47	3.16	$13\times 13$	$19\times 19$	$30\times 30$
9	2.10	3.60	4.50	$13\times 13$	$19\times 19$	$29\times 29$
12	2.80	4.82	5.80	$13\times 13$	$19\times 19$	$28\times 28$
14	3.10	5.21	6.30	$13\times 13$	$19\times 19$	$27\times 27$

^aFor Siemens Oncor, there is no $6\hspace{0.17em}\text{cm}\times 6\hspace{0.17em}\text{cm}$ applicator but a circular applicator with 5 cm diameter.