23-27 January 2017
Bormio, Italy
Europe/Berlin timezone

Performance tests of the Belle II pixel detector data reduction system

Not scheduled
Bormio, Italy

Bormio, Italy



Dennis Getzkow (JLU Gießen)


The Belle II experiment, starting in October 2018, will provide a much higher luminosity as its successor, the Belle experiment. For this achievment, the Belle II-electron-positron collider in Tsukuba, Japan, will make use of a novel nano beam scheme. A pixel detector using DEPleted Field Effect Transistors will be the innermost detector subsystem. It will consist of two layers and in total 40 ladders each with 250 times 768 pixels. The data rate is expected to be ~20 GB/s. Therefore a sophisticated data selection system is needed to filter out backround data. This is where the ONline SElection Nodes (ONSEN) take place. The ATCA based FPGA system performs an online data reduction based on Regions-Of-Interest (ROIs). These regions are calculated via two indepentend systems which perform tracking in the outer detector systems and then figure out regions relevant for physics analysis on the pixel detector ladders. This allows an expected data reduction by a factor of ~30. In April 2016, first tests with two ladders, arranged in two layers, were performed at DESY, Hamburg, Germany. These tests were performed with electron beams with energies up to 5 GeV. Results of performance tests of the ONSEN and the data reduction, respectively, will be shown. This work was supported by the Bundesministerium für Bildung und Forschung (BMBF) under grant number 05H15RGKBA.

Primary author

Dennis Getzkow (JLU Gießen)


Dr Björn Spruck (JGU Mainz) Dr Jens Sören Lange (JLU (Gießen)) Jingzhou Zhao (IHEP Beijing) Klemens Lautenbach (JLU Gießen) Dr Thomas Geßler (JLU (Gießen)) Prof. Wolfgang Kuehn (JLU Giessen) Zhen-An Liu (IHEP Beijing)

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