000000418 001__ 418
000000418 005__ 20161013130018.0
000000418 037__ $$aBELLE2-MTHESIS-2016-006
000000418 041__ $$aeng
000000418 100__ $$aLeonard Koch
000000418 245__ $$aStudy of improved K_S^0 detection for the Belle II Detector
000000418 260__ $$aGiessen$$bII. Physikalisches Institut$$c2015
000000418 300__ $$a126
000000418 500__ $$aPresented on 29 09 2015
000000418 502__ $$aMSc$$bGiessen, University Giessen$$c2015
000000418 520__ $$aIn this work, an online tracking algorithm is developed and evaluated focusing on the reconstruction of charged pions from displaced vertices, the characteristic decay topology of K_s^0 mesons. All six VXD layers are used. The algorithm, which may be used on the FPGA-based PXD DAQ system, is based on the fast Hough transform applied to the hits mapped onto the conformal plane. The amount of background is reduced by a two stage neural network filtering system. Applied to data from a simulation of 10 000 typical Belle II events, the algorithm is adjusted to a fake rate of 90% being considered as tolerable, resulting in a pion reconstruction efficiency of 81.4 %. An alternative setup has a fake rate of 50 % and an efficiency of 63.6 %. The gained K_S^0 reconstruction efficiencies by the additional employment of the algorithm developed in this work are 5.0 % and 1.4 %, respectively, compared to the performance of the existing track finders.
000000418 700__ $$aSören Lange, $$edir.
000000418 700__ $$aWolfgang Kühn$$edir.
000000418 8560_ $$fjens.soeren.lange@desy.de
000000418 8564_ $$uhttps://docs.belle2.org/record/418/files/BELLE2-MTHESIS-2016-006.pdf
000000418 980__ $$aTHESIS