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Emittance meter with CEM. Upgrade : CEM incorporation Two modes of operation Channeltron: Low beam intensity~10pA Faraday cup: Beam intensity > 1nA. Initially we had an Allison type emittance meter. -. 100V. ± V. beam. s. SCANNER. CURRENT. g. L = 70 mm g = 4 mm
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Emittance meter with CEM • Upgrade: CEM incorporation • Two modes of operation • Channeltron: Low beam intensity~10pA • Faraday cup: Beam intensity > 1nA Initially we had an Allison type emittance meter - 100V ± V beam s SCANNER CURRENT g L = 70 mm g = 4 mm V = ± 1000 V (KEPCO) L L = 50 mm g = 2mm V = ± 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.
Emittance meter with CEM Emittances at low intensities: 116Cd at 20 kV Intensity= 15 pA, Scalar time = 0.25 s 225Ra at 20 kV Intensity=13000 cps, Scalar time= 2s e = 3.86 mm mrad e = 4.2 mm mrad