Overall Detector Performance

Working Group

Convenors: Pascal Gay,

Markus Schumacher , Mark Thomson

• Charge of the WG

• Strategy

• How to do ?

• Who does what ?

• Open Questions

• Towards Amsterdam

Prague, 17.11. 02

Markus Schumacher , Bonn Overall Detektor Performance Working Group2

Charge of the Working Group

Evaluation of the detector performance considering the whole detector

Comparison of different sub-detector design/technology options in the context of the detector as a single entity

Provide a forum for discussion on all issues related to the overall detector performance with participation from detector R&D, simulation and physics groups (including our colleagues from the North American and Asian LC-Workshops)

Markus Schumacher , Bonn Overall Detektor Performance Working Group3

Strategy Obtain key performance figures

Perform reconstruction of physics events using information from all subdetectors with full simulation

Study influence of machine backgrounds (occupancy), overlaping events, time structure of accelerator, (mis)allignment and calibration issues, issue of crossing angle of the colliding beams

Develop ID/reco. tools and compare them using well defined benchmark processes

Extract parametrisations for / transfer algorithms to fast simulation packages (e.g. done for flavor tagging)

Perform comparison of physics results between full and fast simulation different detector technology & reco. algorithm options

Provide inputs to the discussion of cost/performance issues

Markus Schumacher , Bonn Overall Detektor Performance Working Group4

How to do it ?

common simulation framework for a fair comprison agree on language and one (maybe) new package (so far: Fortran/C++, BRAHMS/MOKKA, GEANT3/4)

provide a common data format for easy use in physics studies

define and agree on benchmark processes for comparsion (eeWW,ZZ,ttH for jet reco., jet separation, E resolution) (eeWW qqlnu for low angle tracking, flavor charge ID)

Identify key analysis tools to be developed ( reconstruction algorithms, ID tools, accelerator + alignment issues)

Identify key performance numbers to be determined ( E, p, d0 resolutions, reco and tagging eff., fake rates ... )

More detailed and complete list of benchmark processes, tools and key performance numbers on working group web page

Markus Schumacher , Bonn Overall Detektor Performance Working Group5

Who does what ?

detector groups provide inputs about technology options, detector design (granularity, material budget, readout time), very basic performance figures (point/energy/cluster resolutions, dependence on number of cells etc.), noise, ocupancy ....

simulation/software groups implement or ensure implementation of above in simulation, provide common simulation framework and data format

detector groups and simulation/software groups develop and implement basic reconstruction algorithms ( providing tracks, clusters )

overall detector performance group and simulation/software groups provide/ensure existence of analysis tools ( e.g. event reconstruction, ID packages )

overall detector performance group define performance criteria collect result from various groups and distribute those information

overall detector performance group and all (including physics groups) evaluate the performance figures / compare options

Markus Schumacher , Bonn Overall Detektor Performance Working Group6

Analysis tools/topics and Performance Criteria

Tools and Topics

PID + reconstruction for :

e,V0,h0,conversions, ....

quark flavor and charge tag

dE/dx id algorithms

implementation of overlapping events, alignment + calibration, several bunch

crossings, beam crossing angle

Performance Criteria

define physics processes to be studied as benchmarks

specify figures to compare: (e.g.) reco./id/selection effiencies

rejection factors / fake rates resolutions: E, ij ,

Mmiss, ...

compare those figures for 1) different event

topologies 2) technology + reco. options 3) background levels, allignment

and calibration accuracies

Markus Schumacher , Bonn Overall Detektor Performance Working Group7

Some Open Questions and Topics

influence of machine backgrounds due to and time structure of accelerator (vs. readout time) (e.g. assignment of tracks to bunch crossings)

issue of (mis)alignment, calibration, dead channels

hermeticity, forward veto vs. machine backgrounds

influence of non vanishing crossing angle

new and/or more sophisticated analysis tools: (e.g. quark charge tagging, b (c) vs. bbar (cbar) sophisticated implementation of dE/dx for particle ID)

( no complete list, examples from personal preference)

Markus Schumacher , Bonn Overall Detektor Performance Working Group8

Towards Amsterdam

Today: get overview of detector technologies, their implementation and status of simulation and availability and sophistication of ID/analysis tools

Today + Next Weeks: 1) find volunteers for all the open topics 2) decide on and provide common simulation framework and data format

Until Amsterdam: 1) establish common framework and data format 2) write documentation and provide it to all users 3) exchange information between working groups 4) do first studies for evaluation of performance

Amsterdam: plenty of reports on new and interesting results