1. 26 April 2001 Frank Raupach 1 Software and Alignment Project at CMS DRAFT PLAN Work In Progress Contributions From A. Heikkinen / HIP J.Y. Heinonen / HIP Veikko Karimaki / HIP T. Lampen / HIP T. Linden / HIP Valeria Bartsch / Karlsruhe Marumi Kado / CERN Helge Voss / CERN Stephan Koenig / Aachen Jan Olzem / Aachen Andre Ostapchouk /Aachen Britta Schwering / Aachen Bruno Wittmer / Aachen F.R. / Aachen ? / ?

2. 26 April 2001 Frank Raupach 2 General Overview 1 1750 Physicists 150 Institutes 32 Countries Detector: Data/Simulation Raw Data Hits (Digis) Geometry DB Laser reconstruction (LaserBeam Model) Alignment Procedure With Laser System (LinLeastSquare!?) Alignment DB (100  m) Once per Run?

3. 26 April 2001 Frank Raupach 3 General Overview 2 Pattern recognition 1. track reconstruction Alignment procedures with tracks (+ laser) (Methods under study) Alignment DB (30  m) Final track reconstruction Reconstructed event to DB Link to muon system offline Autoalignmentmechanism Rather complicated: O(20000 Si wafers) CorrelationsB-field…

4. 26 April 2001 Frank Raupach 4 Key Elements to achieve the Goals 1 Start: CMSIM + ORCA digis in DB First: MisAlignment procedure in ORCA Alignments tools for ORCA - Deviations on different scales (Helge Voss,…) - LaserBeams … Misaligned digis Reconstruction with stiff tracks Reconstruction of laser beams Geometry without errors Here we are able to analyse the influence of wrong position assignment

5. 26 April 2001 Frank Raupach 5 Key Elements to achieve the Goals 2 Fast Alignment Procedure e.g. fitting global and local parameters simultaneously Alignment Procedure with tracks + laser Alignment DB Physics Analysis with best aligned tracks and vertices e.g. H -> bb,  Problem of correlated errors Near future Technical meeting On Alignment tools middle of may