Studies for a silicon detector in a e/A colliderBenedetto Di Ruzza
BNL EIC Task Force meeting August 28th 2014
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• Momentum resolution studies for a silicon detector in a eRHIC collider using the EICRoot framework.• Some consideration on bremsstrahlung for
electron in silicon.• The ITS Alice upgrade.
outline
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Momentum resolution studies performed using a simple detector model in the EICRoot framework
Momentum resolution studies
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Detector model: barrelMomentum resolution studies
Electron energies: 5, 15 and 20 GeVEta : 0, 0.5, 1,1.5, 2, 2.5, 3
Forward and Rear:
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In each configuration performed the simulation of 2000 events.
Momentum resolution studies
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Crystal ball function “like” used in the fit fit:
Momentum resolution studies
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Crystal ball function like function used in the fit:Momentum resolution studies
P0= alpha, P1= n; P2= mean, P3= sigma, P4=N
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Ratio tail/all events
Momentum resolution studies
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• Repeat the fit with a crystal ball function • change particles and detector design
Still to do:
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electron bremsstrahlung in Si
Plot Energy loss in leadCritical energy From PDG 2013
Si Z=14
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electron bremsstrahlung in Si
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electron bremsstrahlung in SiSome calculation with X0 =9.36 cm
Fraction of energy loss by electrons for bremsstrahlungFor 300 µm silicon: exp -(0.03/9.36)=0.0032
Other calculation: using the Bremsstrahlung energy spectrum
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electron bremsstrahlung in SiSome calculation with X0 =9.36 cm
(thanks to Sasha Bazilevsky for useful discussions)Fraction of energy loss by electrons for bremsstrahlung:Numerical calculation using bremsstrahlung gamma spectrum from PDG:
Ratio of Integral over all spectrum/incoming energy = 0.0032
Number of gammaEnergy (Gev)
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The Alice ITS upgrade
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The Alice ITS upgrade
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The Alice ITS upgrade
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The Alice ITS upgrade (inner barrels)
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The Alice ITS upgrade (outer barrels)
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New model implemented in the simulation by Alexander
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New model implemented in the simulation by Alexander
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New model implemented in the simulation by Alexander
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The ITS upgrade cooling system
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The ITS upgrade cooling system
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ratio
Momentum resolution studies
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ratio
Momentum resolution studies
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ratio
Momentum resolution studies