GDE ILC Reference Design Report (including short physics chapter)

1. Documents to be produced by the end of 2006 Klaus Moenig Ties Behnke • GDE ILC Reference Design Report(including short physics chapter) • Detector Concepts Report(including longer physics chapter) • timescale: Bangalore (March): presentation and discussion of outline • Vancouver (July): detailed discussion with the community • Valencia (November): presentation of final draft • DCR performance chapter: look at small number of selected benchmarks, • distribute the reactions among the concepts  avoid entering into competition at this stage • currently no solid and understood full simulation, although a lot of recent progress • {e.g. when running current reconstruction on GEANT4 detector simulation, goal of • DE/E = 30%/sqrt(E) not yet achieved  rely on fast simulation in the mean time} • T Behnke: unlikely to be achieved on the timescale of DCR •  need to be careful not to draw wrong conclusions

2. Recent developments (LDC software) I Frank Gaede • LCIO: plans: check usability of data model, e.g. track parameters • need to make LCIO more convenient and efficient, e.g. allow requesting all • tracks for one MCParticle • Marlin (Modular Analysis & Reconstruction for the LINear collider): • software modules called processors, each has set of input parameters, • order of processors is defined via XML steering file  easy to exchange modules without • recompiling, can run the same processor with different parameter set in one job • Strong encouragement to register with theGRID (http://lcg-registrar.cern.ch) • (example DESY: 10 outdated ILC-dedicated machines, GRID: 300, beyond Europe: few 1000) • GRID has already been used to produce event samples, accessible on the web: • 450 k events at 500 GeV: Z0, uds, cc, bb, ttbar, WW, ZH

3. Recent developments (LDC software) II Steve Aplin • Tracking status (based on LEP code previously in BRAHMS): • TPC pattern recognition modified ALEPH code, final track fit from DELPHI Kalman-filter • VTX- & SIT-hits treated as individual track element & cov matrix, included in trk matching/fitting • new Marlin processor to suppress low energy curlers, physics impact needs to be determined • kink finding not yet included • efficiency studies to be done soon, initial studies: > 93%, but track splitting still a problem • Particle flow algorithms: • PFA performance at high energies unacceptable due to deficiencies in other parts of rec’ code • missing kink-finding gave rise to large tails in E(rec) – E(true) distribution • MC true information only available at particle origin, not at point of kink, and currently no • place to store this information in LCIO • errors from clustering and from track-cluster matching due to differences in calibration • gaps between subdetectors, missing in geometry available for reconstruction  split clusters •  urgent need to solve some ‘technical’ issues Predag Krstonosic

4. Reaction to LCFI presentations • Vertexing & flavour tagging highlighted as missing in the current reconstruction software • in a number of presentations • response to our talks was therefore very positive: • Frank Gaede emphasised need to make our code available in the form of Marlin processor(s) in order to integrate it into the LDC software framework • Ties Behnke gave advice to think about which changes will need to be made in LCIO classes to allow output from our code to be stored well in advance of the release • Mark Thomson’s summary talk: • ‘vertex reconstruction: sophisticated code under development – real progress • vital for many physics studies • high priority to get this in Marlin • promised by summer’