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arXiv · 1309.7896

A Tracker for the Mu3e Experiment based on High-Voltage Monolithic Active Pixel Sensors

Niklaus Berger·Heiko Augustin·Sebastian Bachmann·Moritz Kiehn·Ivan Perić·Ann-Kathrin Perrevoort·Raphael Philipp·André Schöning·Kevin Stumpf·Dirk Wiedner·Bernd Windelband·Marco Zimmermann
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Abstract

The Mu3e experiment searches for the lepton flavour violating decay mu+ -> e+e-e+, aiming for a branching fraction sensitivity of 10^-16. This requires an excellent momentum resolution for low energy electrons, high rate capability and a large acceptance. In order to minimize multiple scattering, the amount of material has to be as small as possible. These challenges can be met with a tracker built from high-voltage monolithic active pixel sensors (HV-MAPS), which can be thinned to 50 um and which incorporate the complete read-out electronics on the sensor chip. To further minimise material, the sensors are supported by a mechanical structure built from 25 um thick Kapton foil and cooled with gaseous helium.

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Niklaus Berger, Heiko Augustin, Sebastian Bachmann, Moritz Kiehn, Ivan Perić, Ann-Kathrin Perrevoort, Raphael Philipp, André Schöning, Kevin Stumpf, Dirk Wiedner, Bernd Windelband, Marco Zimmermann. 2013-09-30. A Tracker for the Mu3e Experiment based on High-Voltage Monolithic Active Pixel Sensors. https://doi.org/10.1016/j.nima.2013.05.035

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