LCFI physics studies meeting, 28 th June 05 Sonja Hillertp. 1 Report from ILC simulation workshop, DESY June Aim of workshop: preparation for Snowmass;  get overview of which tools are available and which are still missing for comparison of the three detector concepts  intention to accelerate software development, but manpower is short everywhere European framework (Introduction, Ties Behnke):  have a “complete“ simulation and reconstruction chain in place for Snowmass  update the workshop DVD to include as complete a software package as possible  core packages: try as much as possible to keep the door open for JAVA and the application of JAVA packages and code (presently only works for LCIO, not for reconstruction) F. Gaede: Java/C++ interfacing technically feasible, implementation not so straightforward how urgently needed?  has fairly low priority at present both in Europe and in the US

LCFI physics studies meeting, 28 th June 05 Sonja Hillertp. 2 Central tools (Frank Gaede)  added first implementations of generic tracker raw data classes (TPC, VTX, Si-strip)  need to define conventions how to use LCIO  a fairly complete OO-software framework exists for the LDC study based on MOKKA, MARLIN, LCIO, LCCD – only missing ingredient is geometry definition GEAR (GEometry A PI for Reconstruction) could fill that gap (proposal)  implementation possibly by the end of the year (Vienna workshop?)  high-level information needed for reconstruction (different from local info for simulation)  XML files used for subdetector description – one class for every subdetector type: description of detector shape and readout geometry  in addition: material properties: point properties (density, material, radiation lengths) distance properties: integrated along (straight?) path  aim: provide first mini-implementation with XML files for current reconstruction (TPC, ECAL, HCAL) integrated in MARLIN for Snowmass; there: discussion with other concepts

LCFI physics studies meeting, 28 th June 05 Sonja Hillertp. 3 Tracking software in MARLIN (Steve Aplin)  TPC pattern recognition: modified ALEPH code; Kalman filter developed for DELPHI  there exist more recent algorithms, intention to update; currently most powerful: combinatorial Kalman filter (R. Mankel) Further issues:  potential problem: occasionally, tracks are broken up and reconstructed in several pieces – a known problem in BRAHMS, needs to be investigated  intend to incorporate vertex hits into track fit – discussion after the talk: time scale for that step at present unclear; could become much simpler once the tools have been updated to newer algorithms; due to short manpower probably not the first priority Conclusion of the talk: to make serious optimisation and physics studies, realistic tracking code is needed

LCFI physics studies meeting, 28 th June 05 Sonja Hillertp. 4 The US software framework (Norman Graf)  production of 1 ab -1 MC samples with ILC detector configuration using WHIZARD (T. Barklow) 500 GeV events already available as LCIO output on ftp server, 1000 GeV samples to follow  developed “Compact Geometry Description“ (XML) and GeomConverter: small Java program for converting from compact description to a variety of other formats  detector variants: runtime XML format allows variations in det. geometries to be easily set up and studied; plan to support GLD and LDC, need help in defining geometries  reconstruction / analysis: based on JAS3; org.lcsim provides access to full software suite: autoupdates with new releases (now ~ weekly)  Aim to characterise / optimise performance of the detector concepts for CDR starting at Snowmass