Download - Emittance meter with CEM
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Emittance meter with CEM
Initially we had an Allison type emittance meter
s
-100V
SCANNER CURRENT
± V
gL
beam
L = 70 mmg = 4 mmV = ± 1000 V (KEPCO)
Limitations• Could not take a scan for beam currents
below 1 nA• between 1-3 nA one had to use reverse
bias to take a scan.
Upgrade: CEM incorporation
Two modes of operation• Channeltron: Low beam intensity~10pA• Faraday cup: Beam intensity > 1nA
L = 50 mmg = 2mmV = ± 1000 V (KEPCO)
Emittance meter with CEM
Emittances at low intensities:
116Cd at 20 kV Intensity= 15 pA, Scalar time = 0.25 s
e = 3.86 mm mrad
225Ra at 20 kV Intensity=13000 cps, Scalar time= 2s
e = 4.2 mm mrad