LCLS Conceptual Design Report - Stanford Synchrotron Radiation ...

γε x,y (µm)
y n
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5
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L C L S C O N C E P T U A L D E S I G N R E P O R T
–5
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xn 5
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1-2002
8560A195
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∆z (mm)
γεx
γεy
ζ x,y
x n '
1.2
0.8
0.4
10
0
–10
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xn 5
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∆z (mm)
Figure 6.33 Longitudinal distribution of particles in the beam at the exit of L0-2. In this figure, the
bunch head is at the left, as in the convention of Chapter 7, Accelerator. The peak rf
field at the cathode is 120 MV/m.
The optimization of the beamline for the gun run at 120 MV/m gives a projected emittance
very similar to that obtained when optimizing the beamline for the gun run at 140 MV/m. See
Table 6.5. Similarly, for a rise time for the 10 ps pulse of 0.7 ps, a projected emittance as small as
0.8 µm has been computed with the gun run at 120 MV/m.
6-62 ♦ I NJECTOR
ζ x
ζ y