CDC Scrutineer TalkCDC Scrutineer Talk

Elliott WolinElliott WolinGlueX Collaboration MeetingGlueX Collaboration Meeting

Jefferson LabJefferson Lab9-Sep-20049-Sep-2004

Scrutineer?Scrutineer?

scrutineerscrutineer

n. a scrutinizer; specifically, an n. a scrutinizer; specifically, an examiner of votes, as at an election.examiner of votes, as at an election.

scrutinizerscrutinizer

n : a careful examiner; someone who n : a careful examiner; someone who inspects with great careinspects with great care

StrategyStrategy

Assume role of a skeptical reviewerAssume role of a skeptical reviewerPresent list of questions/concerns not Present list of questions/concerns not

covered in Design Report and in covered in Design Report and in DocDBDocDB

Please add to my list!Please add to my list!

But first…But first…

I find the project in good shapeI find the project in good shapeConfidence in CMU to solve Confidence in CMU to solve

remaining problemsremaining problemsOnly concern is effectiveness of Only concern is effectiveness of

dE/dx in magnetic field, with real dE/dx in magnetic field, with real preamps, etc.preamps, etc.

Skeptical Reviewer’s Skeptical Reviewer’s ConcernsConcerns

ConceptualConceptualPerformancePerformanceMechanicalMechanicalServices (gas,electrical,hv,etc.)Services (gas,electrical,hv,etc.)Onboard electronicsOnboard electronicsReconstruction and AnalysisReconstruction and Analysis

ConceptualConceptual

No VTX implies need for re-optimization No VTX implies need for re-optimization of STC/CDC/FDC geometryof STC/CDC/FDC geometry

New Cerenkov implies reevaluation of New Cerenkov implies reevaluation of dE/dx requirementsdE/dx requirements

Is prototype plan adequate…need more? Is prototype plan adequate…need more? In B field?In B field?

Why not resistive wires? Why not resistive wires? If dE/dx not needed skip ADCs? Or drift?If dE/dx not needed skip ADCs? Or drift?

PerformancePerformance Look at other gases? CO2 - long pulse, pile-Look at other gases? CO2 - long pulse, pile-

up?up? Understand aging betterUnderstand aging better Understand Lorentz angle effects betterUnderstand Lorentz angle effects better Effect of breakdown, broken wire?Effect of breakdown, broken wire? Verify dE/dx works in B fieldVerify dE/dx works in B field Gain variations vs V, wire sag, gas purity, etc.Gain variations vs V, wire sag, gas purity, etc. Cross talk – straws, preamps, via HV, etc.Cross talk – straws, preamps, via HV, etc. Rate effects – V sag, preamps, x-talk, heat, Rate effects – V sag, preamps, x-talk, heat,

signal pile-up, etc.signal pile-up, etc.

MechanicalMechanical Verification of matl’s, glue, techniquesVerification of matl’s, glue, techniques Glue lifetime – radiation damage, etc.Glue lifetime – radiation damage, etc. Failure mode analysisFailure mode analysis How to repair? Time? Replace wire?How to repair? Time? Replace wire? Survey, align requirements? Plan?Survey, align requirements? Plan? Supports, stability, deflections, vibration?Supports, stability, deflections, vibration? QC (clean,glue,crimp,tension) – students?QC (clean,glue,crimp,tension) – students? Al vs Cu vs Au? mylar vs kapton?Al vs Cu vs Au? mylar vs kapton? Metal coating thickness, skin depth?Metal coating thickness, skin depth? Are compound angle problems under Are compound angle problems under

control?control? Interfaces, keep out zones, installation plan?Interfaces, keep out zones, installation plan?

ServicesServices

Gas distrib, uniform flow, purity, cleaning?Gas distrib, uniform flow, purity, cleaning?Room for cables, services? Mass?Room for cables, services? Mass?HV dist, granularity, currents, cable type?HV dist, granularity, currents, cable type?Discharges - HV cap, resistor size calc?Discharges - HV cap, resistor size calc?Power, heat, noise, shielding, grounding?Power, heat, noise, shielding, grounding? Is temperature rise a problem? Gas flow Is temperature rise a problem? Gas flow

rate?rate?

Onboard ElectronicsOnboard Electronics

Preamp design?Preamp design?Preamp mounting, power, heat, x-Preamp mounting, power, heat, x-

talk?talk?Cable type, quality, thickness, max Cable type, quality, thickness, max

length?length?Signal shape variations? Shaping?Signal shape variations? Shaping?

Reconstruction and AnalysisReconstruction and Analysis

Calib plan – special runs? Survey Calib plan – special runs? Survey reqs?reqs?

Pat rec – spiraling tracks, bad straws, Pat rec – spiraling tracks, bad straws, showers, event pileup, x-talk, showers, event pileup, x-talk, ambiguities, ambiguities,

Track fitting – mult. scatt, dE/dx, Track fitting – mult. scatt, dE/dx, Kalman filter?Kalman filter?

What if no tagger info?What if no tagger info?

ConclusionsConclusions

CDC project in good shapeCDC project in good shapeSome open questionsSome open questionsSome tests still neededSome tests still needed

CMU headed in the right directionCMU headed in the right directionSeem to have enough time, people, $$?Seem to have enough time, people, $$?

““Reviewer’s” questions should be Reviewer’s” questions should be satisfied by adequate documentation satisfied by adequate documentation of past work, and planned future workof past work, and planned future work