Theory, Design and Tests on a Prototype Module of a Compact ...

List of Figures
1.1 The Bragg peak phenomenon. Comparison between
proton <strong>and</strong> electron penetration depth in water. Also
shown is a proton depth dose curve with a spread-out
Bragg (SOBP) of 5 cm. 4
1.2 The Spread out Bragg peak. Combining beams
with different energies it is possible to describe a
longitudinal profile. 5
1.3 A sketch of Loma Linda radiotherapy center in
California. 5
2.1 Dispersion diagram of a periodic structure (loaded
waveguide); unloaded cavity case is shown for
comparison. 8
2.2 N + 1 coupled cavities. The first <strong>and</strong> last cells are
half cavities which act as an electric mirror for the
boundary conditions. 9
2.3 N = 7 coupled cavities. The Brillouin diagram is
sampled in 7 frequencies. We can recognize modes 0,
π/2 <strong>and</strong> π. 10
2.4 Schematic view of the Wideröe drift-tube linac. 12
2.5 Schematic view of the Alvarez drift-tube linac. 13
2.6 Schematic view of the Side Coupled Drift-Tube Linac. 14
2.7 Different solutions for the realization of a biperiodic
chain of cavities. 15
2.8 A Side Coupled Linac example. 15
2.9 The dispersion diagrams in the case of a biperiodic
structure with fa = 3 GHz, fc = 3 GHz, k = 0.04,
k2 = 0.005 <strong>and</strong> k3 = 0 on the left <strong>and</strong> fc = fa/ √ 1 − k2
on the right. 16
2.10 A perspective image of a LIBO installation. 17
2.11 The layout of the first module of LIBO, with details
of a half-cell-plate (left) <strong>and</strong> of a bridge coupler
(right). 18
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