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E CM bias in the presence of Beamstrahlung. Arik Florimonte & Mike Woods, SLAC. September 15, 2004. Summary of E CM Bias studies w/ Beamstrahlung OFF. (larger for WARM). (comparable at WARM, COLD). (larger for WARM). E-Spread + E-Z correlation + Y-Z Kink instability E CM Bias.
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ECMbias in the presence of Beamstrahlung Arik Florimonte & Mike Woods, SLAC September 15, 2004
Summary of ECM Bias studies w/ Beamstrahlung OFF (larger for WARM) (comparable at WARM, COLD) (larger for WARM) E-Spread + E-Z correlation + Y-Z Kink instability ECM Bias E1 and E2 are beam energies measured by the energy spectrometers. (ISR and beamstrahlung are turned off for this study.) (larger for COLD) (comparable at WARM, COLD) (larger for WARM) Wakefields + Disruption Y-Z Kink instability Summary of ECMbias
NLC TESLA Summary of ECMbias NLC’
E1 and E2 are beam energies measured by the energy spectrometers. (ISR and beamstrahlung are turned off for this study.) Definition of ECMbias (BSL OFF) Definitions of ECMbias (BSL ON) studied Vary cutoff energy from 480-495 GeV where gives best results
Actually changes luminosity and hence beamstrahlung, due to waist focusing. So not ok for estimating E_bias!
NLC1 NLC NLC w/ random-ordered energy NLC NLC w/ random-ordered energy Negligible difference in 2 distributions Clear difference in 2 distributions NLC NLC w/ random-ordered energy Tails are similar in both E1+E2 and E1-E2 distributions NLC NLC w/ random-ordered energy
TESLA1 TESLA TESLA w/ random- ordered energy TESLA TESLA w/ random- ordered energy Clear difference in 2 distributions Negligible difference in 2 distributions TESLA TESLA w/ random-ordered energy Tails are similar in both E1+E2 and E1-E2 distributions TESLA TESLA w/ random-ordered energy
NLC’ NLC’ NLC’ w/ random-ordered energy NLC’ NLC’ w/ random-ordered energy Clear difference in 2 distributions Competing/cancelling ECM bias contributions NLC’ NLC’ w/ random-ordered energy Tails are similar in both E1+E2 and E1-E2 distributions NLC’ NLC’ w/ random-ordered energy
Offset scan, ECMbias vs. y-offset Beamstrahlung turned on Ecutoff = 495 GeV Espread on- gaussian E
Offset scan, ECMbias vs. y dispersion Beamstrahlung turned on Ecutoff = 495 GeV Espread on- gaussian E
NLC TESLA Summary of ECMbias in presence of BSL (uses gaussian E results w/ Ecutoff = 495 GeV) NLC’
Summary of ECMbias without BSL Summary of ECMbias in presence of BSL (uses gaussian E results w/ Ecutoff = 495 GeV)