May 10, 2012 Thursday 15:30
Hans Drevermann, CERN
The needle in the hay stack (Samanlıkta iğne aramak)

Abstract:In the LHC experiment ATLAS at CERN the charged tracks are measured by recording a small number of space points along the tracks. The visual examination of tracks via their space points is made difficult, due to problems of pattern recognition in human vision and the very high background from space points of a) low momentum tracks, b) many other interactions and c) possible noise. A number of methods are presented, which reduce the backgrounds, allow visual track examination through special projections, determine the vertex position of the interesting interaction in a high-pileup environment. On a random event with about 40k space points, these methods can clearly identify the few spacepoints which belong to 40 tracks (with PT>1 GeV/c) of the interesting interaction.