. 2023 Dec 6;13:21466. doi: 10.1038/s41598-023-44409-8

Table 2.

Track and dose average LET of total fluence (TEF) and secondary electrons (SE) at water depth = 1.35 cm.

Field size (cm × cm)	Off-axis distance (cm)	Track-average LET (keV/µm)		Dose-average LET (keV/µm)		RBE_M relative to ⁶⁰Co gamma rays
Field size (cm × cm)	Off-axis distance (cm)	TEF	SE	TEF	SE	RBE_M relative to ⁶⁰Co gamma rays
0.7 × 0.7	0	0.242	1.476	2.435	6.718	1.07 ± 0.32
0.9 × 0.9	0	0.241	1.462	2.432	6.704	1.08 ± 0.32
1.8 × 1.8	0	0.242	1.461	2.436	6.704	1.10 ± 0.33
2.2 × 2.2	0	0.242	1.461	2.439	6.706	1.10 ± 0.33
2.7 × 2.7	0	0.243	1.463	2.441	6.710	1.11 ± 0.33
3.1 × 3.1	0	0.242	1.462	2.440	6.708	1.11 ± 0.33
3.6 × 3.6	0	0.244	1.465	2.446	6.714	1.13 ± 0.34
4.5 × 4.5	0	0.245	1.455	2.451	6.725	1.13 ± 0.34
10 × 10	0	0.248	1.478	2.474	6.735	1.13 ± 0.34
0.7 × 0.7	0.175	0.242	1.477	2.436	6.724	1.07 ± 0.34
0.9 × 0.9	0.225	0.242	1.473	2.435	6.716	1.08 ± 0.32
1.8 × 1.8	0.45	0.242	1.462	2.436	6.704	1.10 ± 0.33
2.2 × 2.2	0.55	0.242	1.463	2.438	6.707	1.10 ± 0.33
2.7 × 2.7	0.675	0.243	1.467	2.441	6.711	1.11 ± 0.33
3.1 × 3.1	0.775	0.243	1.462	2.443	6.708	1.11 ± 0.33
3.6 × 3.6	0.9	0.244	1.477	2.446	6.724	1.12 ± 0.34
4.5 × 4.5	1.125	0.245	1.472	2.449	6.723	1.14 ± 0.34
10 × 10	2.5	0.250	1.504	2.478	6.771	1.14 ± 0.34
0.7 × 0.7	0.35	0.241	1.472	2.434	6.712	1.08 ± 0.32
0.9 × 0.9	0.45	0.241	1.473	2.434	6.716	1.08 ± 0.32
1.8 × 1.8	0.9	0.242	1.464	2.439	6.708	1.11 ± 0.33
2.2 × 2.2	1.1	0.243	1.466	2.444	6.713	1.12 ± 0.34
2.7 × 2.7	1.35	0.244	1.475	2.446	6.724	1.12 ± 0.34
3.1 × 3.1	1.55	0.245	1.479	2.448	6.730	1.12 ± 0.34
3.6 × 3.6	1.8	0.245	1.484	2.450	6.737	1.13 ± 0.34
4.5 × 4.5	2.25	0.246	1.493	2.455	6.747	1.14 ± 0.34
10 × 10	5.0	0.253	1.517	2.483	6.792	1.14 ± 0.34
0.7 × 0.7	1.35	0.278	1.526	2.600	6.878	1.63 ± 0.49
0.9 × 0.9	1.45	0.292	1.611	2.639	6.984	1.62 ± 0.49
1.8 × 1.8	1.9	0.296	1.630	2.661	7.010	1.79 ± 0.54
2.2 × 2.2	2.1	0.290	1.592	2.644	6.966	1.76 ± 0.53
2.7 × 2.7	2.35	0.304	1.664	2.694	7.065	1.86 ± 0.56
3.1 × 3.1	2.55	0.301	1.627	2.685	7.026	1.85 ± 0.56
3.6 × 3.6	2.8	0.293	1.591	2.657	6.976	1.75 ± 0.52
4.5 × 4.5	3.25	0.281	1.560	2.611	6.911	1.52 ± 0.46
10 × 10	6.0	0.261	1.549	2.527	6.852	1.52 ± 0.46
0.7 × 0.7	2.35	0.311	1.526	2.764	6.878	1.74 ± 0.56
0.9 × 0.9	2.45	0.321	1.539	2.796	7.054	1.77 ± 0.53
1.8 × 1.8	2.9	0.350	1.703	2.863	7.239	1.92 ± 0.58
2.2 × 2.2	3.1	0.355	1.719	2.876	7.259	1.95 ± 0.58
2.7 × 2.7	3.35	0.371	1.752	2.922	7.315	2.02 ± 0.61
3.1 × 3.1	3.55	0.374	1.756	2.931	7.330	2.04 ± 0.61
3.6 × 3.6	3.8	0.385	1.773	2.957	7.366	2.08 ± 0.62
4.5 × 4.5	4.25	0.393	1.762	2.980	7.386	2.11 ± 0.63
10 × 10	7.0	0.320	1.673	2.778	7.124	2.11 ± 0.63

We also include the predicted RBE_M for dicentrics determined in human lymphocytes. The combined standard uncertainty of 0.6% (coverage factor k = 1)²⁵.