Table 2.

Matched beam parameters for linacs 1 to 9. Profiles assessed for a 30 × 30 cm² field at 10 cm depth in the in‐plane (IP) and cross‐plane (XP) directions. PDDs are taken for a 10 × 10 cm² field at either 100 or 90 cm SSD for beam quality matching

Linac		Flatness (%)		Symmetry (%)		Quality (90 SSD)		Quality (100 SSD)		Output
#	Model	IP	XP	IP	XP	PDD20,10	TPR20,10	PDD20,10	TPR20,10	(cGy/MU)
1	VersaHD	103.8	104.4	100.3	100.8	0.574	0.666			0.996
2	Synergy	103.9	104.0	100.1	100.1			0.588	0.684	1.003
3	VersaHD	104.8	104.4	101.1	100.6	0.574	0.669			0.998
4	VersaHD	103.8	103.7	100.0	100.0	0.573	0.665			0.996
5	Synergy	104.3	104.5	100.7	100.8			0.585	0.682	1.005
6	VersaHD	105.1	104.9	100.9	100.7	0.576	0.669	0.589	0.687	0.995
7	Synergy	104.0	103.8	100.8	100.7			0.588	0.685	1.000
8	Synergy	104.1	103.9	100.7	100.1			0.587	0.684	1.005
9	VersaHD	104.0	103.9	100.3	100.4			0.572	0.665	1.000
Standard deviation		0.5	0.4	0.4	0.3	0.002	0.003	0.007	0.009	0.004
Baseline		104.8	104.4	100.0	100.0	0.574	0.669	0.588	0.685	1.000

TPR: tissue phantom ratio.