Table 1.

Reference conditions for MV‐scatter map and variable parameters used in this study.

Parameter	Description
Reference conditions for MV‐scatter map acquisition	Field size: 10.0 × 10.0 cm2, dose rate: 400 MU/min, gantry and ring angles: 0°
X field size [cm]	2.0, 4.0, 6.0, 8.0, 10.0, 12.0, 14.0, 15.0
Y field size for each X field size [cm]	2.0, 4.0, 6.0, 8.0, 10.0, 12.0, 14.0, 15.0
Dose rate [MU/min]	100, 150, 200, 250, 300, 350, 400, 450, 500
Field size for each dose rate [cm2]	2.0 × 2.0, 4.0 × 4.0, 6.0 × 6.0, 8.0 × 8.0, 10.0 × 10.0, 12.0 × 12.0, 14.0 × 14.0, 15.0 × 15.0
Gantry angle [°]	0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330
Ring angle [°]	−20, 0, +20