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This report discusses the progress made in various aspects of particle track recognition and space point reconstruction at Geneva University as of March 31, 2004. It outlines the methods for cluster finding, space point definition, and track fitting in particle physics experiments. Key algorithms developed include a pattern recognition system for track identification and a fitting procedure using circular and linear methods to determine particle trajectories. Promising developments are anticipated by the end of May, enhancing the precision of measurements in high-energy physics.
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MICE TPG Reconstruction • Cluster finding • Space point reconstruction • Track recognition • Track fit • GENEVA UNIVERSITY • 31 March 2004 Voloshyn Olena Geneva University
status end of march: I Cluster finding written, to be tested, (promised end of march) II Space point reconstruction : almost finished, missing implemetation of errors on space points III Track recognition (exists in HARP code, and in G4MICE for SciFi) IV Track fit (exists in HARP code and in G4MICE for SciFi) all promised for end of May. Geneva University
Space Point definition • Crossing of the clusters close in time gives the space point position in plane x-y. • z coordinate of space point is defined • z=vdr*tdr • U X V Geneva University
Track recognition • Pattern recognition algoritm groups the space point recognized as belonding to the same track and searches the following point in the volume of a truncated cone with the axis defined by the previous points. • The parameters of the cone will be optimised for 200 MeV track. . . . . . a Radius Forward acceptance Geneva University
Track fit • Fit is performed in two steps: • circular fit in the x-y plane that alows to determine the inverse of the radius of curvature r, the impact parameter in the x-y plane d0 and the angle between the projection on this plane of the particle momentum at the impact point and the X axis Fo; • Linear fit in the Sxy-Z plane that alows to determine the tangent of the dip angle and the Zo coordinate at the impact point. y z tg a p Oo x Zo Sxy do Geneva University
(at a later stage) the calculated helix parameters will be used as a seed for a futher Kalman fit which handles multiple scattering and energy loss. • The energy loss (which is derived from amplitude) and momentum (as derived from curvature and phase advance) will be estimated. Geneva University