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Table 1 Summary of the results of the periodic radiation beam quality assurance measurements.

From: Commissioning and early experience with a new-generation low-energy linear accelerator with advanced delivery and imaging functionalities

  Unique Clinac iX
Output(% difference from ref.) Tolerance: <2% -0.3 ± 0.2% [-0.8,+0.2]   -0.1 ± 0.4% [-0.9,+1.0]  
Energy: Tolerance:<2%     
   %diff. ratio @5.6 cm/dmax 0.0 ± 0.0 [-0.1,0.1]   0.1 ± 0.1 [-0.2,0.6]  
   %diff. ratio @7.6 cm/dmax -0.1 ± 0.1 [-0.3, 0.1]   -0.1 ± 0.1 [-0.3, 0.4]  
   %diff. ratio @11 cm/dmax -0.1 ± 0.1 [-0.3, 0.1]   -0.0 ± 0.2 [-0.3, 0.6]  
EDW _WF(% difference from ref.) Tolerance: <2% 0.0 ± 0.2 [-0.1,0.1]   -0.0 ± 0.3 [-0.1,0.5]  
  X dir. Y dir. X dir. Y dir.
Field Size[cm] 10 × 10 cm2, dmax Tolerance: <2 mm 10.03 ± 0.05(ref.10.02) [10.00, 10.14] 10.06 ± 0.06(ref.10.07) [9.99, 10.13] 10.10 ± 0.03(ref.10.02) [10.08, 10.11] 9.99 ± 0.02(ref.10.04) [9.94, 10.05]
Field Size[cm] 20 × 20 cm2, dmax Tolerance: <3% 20.13 ± 0.01(ref.20.13) [20.10, 20.14] 20.14 ± 0.02(ref.20.13) [20.11, 20.18] 20.21 ± 0.01(ref.20.21) [20.18, 20.24] 20.09 ± 0.02(ref.20.02) [20.02, 20.10]
Flatness[%] 10 × 10 cm2, dmax: Tolerance: <3% 0.8 ± 0.04 (ref.0.7) [0.7, 0.9] 0.9 ± 0.04 (ref.0.9) [0.8, 0.9] 1.2 ± 0.09 (ref.1.1) [1.0, 1.5] 0.8 ± 0.05 (ref.0.9) [0.8,1.0]
Flatness[%] 20 × 20 cm2, dmax: Tolerance: <3% 1.5 ± 0.04 (ref.1.5) [1.4, 1.6] 2.0 ± 0.06 (ref.1.8) [1.9, 2.1] 1.1 ± 0.12 (ref.1.0) [0.9, 1.4] 1.6 ± 0.10ref.1.7) [1.4,1.8]
Symmetry[%] 10 × 10 cm2, dmax: Tolerance: <103% 100.6 ± 0.2 (ref.100.6) [100.4, 100.9] 100.3 ± 0.2(ref.100.4) [100.1, 100.7] 100.5 ± 0.2 (ref.100.3) [100.3, 101.1] 100.5 ± 0.2 (ref.100.3) [100.2, 101.1]
Symmetry[%]20 × 20 cm2, dmax: Tolerance: <103% 101.1 ± 0.1(ref.101.3) [101.0, 101.2] 100.4 ± 0.2 (ref.100.3) [100.2, 100.7] 100.6 ± 0.2 (ref.100.4) [100.1, 101.1] 101.4 ± 0.3 (ref.101.7) [100.5, 101.8]
  1. Measurements were performed by means of the GLAaS method (except output, where a 0.6 cm3 ion chamber was used) on the UNIQUE linac and, as comparison, on the Clinac iX linac operational at authors institute. Results derived from weekly controls over a period of one year and included stability of: dose output, beam quality, EDW wedge factor, field size, beam homogeneity and symmetry. Measurement settings are reported in the first column. Mean results were shown together with their standard deviation and range (in square brackets) for UNIQUE and Clinac iX in the second and third columns. Reference baseline was reported within normal brackets