ECMbias in the presence of Beamstrahlung

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ECMbias in the presence of Beamstrahlung
Arik Florimonte Mike Woods, SLAC
September 15, 2004
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Summary of ECM Bias studies w/ Beamstrahlung OFF
(larger for COLD)
(comparable at WARM, COLD)
(larger for WARM)
Wakefields Disruption Y-Z Kink
instability
Summary of ECMbias
LC Machine Design ltECMbiasgt (Dy 0) s(ECMbias) (Dy 0) Max(ECMbias) vary Dy, hy
WARM-500 520 ppm 170 ppm 1000 ppm
COLD-500 50 ppm 30 ppm 250 ppm
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NLC
TESLA
Summary of ECMbias
NLC
LC Machine Design ltECMbiasgt (Dy 0) s(ECMbias) (Dy 0) Max(ECMbias) vary Dy, hy
WARM-500 520 ppm 170 ppm 1000 ppm
COLD-500 50 ppm 30 ppm 250 ppm
NLC'-500 0 ppm 10 ppm 50 ppm
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Definition of ECMbias (BSL OFF)
Definitions of ECMbias (BSL ON) studied
Vary cutoff energy from 480-495 GeV
where
gives best results
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Actually changes luminosity and hence
beamstrahlung, due to waist focusing. So not ok
for estimating E_bias!
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(No Transcript)
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(No Transcript)
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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 E1E2 and E1-E2
distributions
NLC NLC w/ random-ordered energy
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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 E1E2 and E1-E2
distributions
TESLA TESLA w/ random-ordered energy
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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 E1E2 and E1-E2
distributions
NLC NLC w/ random-ordered energy
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Offset scan, ECMbias vs. y-offset Beamstrahlung
turned on
Ecutoff 495 GeV
Espread on- gaussian E
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Offset scan, ECMbias vs. y dispersion Beamstrahlun
g turned on
Ecutoff 495 GeV
Espread on- gaussian E
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NLC
TESLA
Summary of ECMbias in presence of BSL (uses
gaussian E results w/ Ecutoff 495 GeV)
NLC
LC Machine Design ltECMbiasgt (Dy 0) s(ECMbias) (Dy 0) Max(ECMbias) vary Dy, hy
WARM-500 970 ppm 140 ppm 1120 ppm
COLD-500 170 ppm 40 ppm 350 ppm
NLC'-500 2 ppm 23 ppm -190 ppm
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Summary of ECMbias without BSL
LC Machine Design ltECMbiasgt (Dy 0) s(ECMbias) (Dy 0) Max(ECMbias) vary Dy, hy
WARM-500 520 ppm 170 ppm 1000 ppm
COLD-500 50 ppm 30 ppm 250 ppm
NLC'-500 0 ppm 20 ppm 50 ppm
Summary of ECMbias in presence of BSL (uses
gaussian E results w/ Ecutoff 495 GeV)
LC Machine Design ltECMbiasgt (Dy 0) s(ECMbias) (Dy 0) Max(ECMbias) vary Dy, hy
WARM-500 970 ppm 140 ppm 1120 ppm
COLD-500 170 ppm 40 ppm 350 ppm
NLC'-500 2 ppm 23 ppm -190 ppm