Commissioning and Charge Readout Calibration of a 5 Ton Dual Phase Liquid Argon TPC

Abstract

Dual phase time projection chambers with amplification of ionization electrons provide a novel technique for measuring and analyzing rare events with excellent spatial resolution and great calorimetric properties. This thesis describes the commissioning of the WA105 3x1x1 m3 dual phase liquid argon detector, built to demonstrate the performance of this kind of detector on large scales in order to determine the viability of giant dual phase time projection chambers in long baseline neutrino oscillation experiments. The properties of the insulation and the main tank vessel are described and analyzed, such as the pressure, temperature and argon purity requirements during operation in order to guarantee stable conditions and good event tracking. As signals are induced due to electrons from ionizing radiation, crosstalk is caused by capacitive couplings between strips of the charge readout plane and in the electronics of the data acquisition. These induced signals are studied and compared to capacitance and pulsing measurements on one anode module and an equivalent circuit model is introduced to quantitatively describe this crosstalk. --> Dual phase time projection chambers with amplification of ionization electrons provide a novel technique for measuring and analyzing rare events with excellent spatial resolution and great calorimetric properties. This thesis describes the commissioning of the WA105 3x1x1 m3 dual phase liquid argon detector, built to demonstrate the performance of this kind of detector on large scales in order to determine the viability of giant dual phase time projection chambers in long baseline neutrino oscillation experiments. The properties of the insulation and the main tank vessel are described and analyzed, such as the pressure, temperature and argon purity requirements during operation in order to guarantee stable conditions and good event tracking. As signals are induced due to electrons from ionizing radiation, crosstalk is caused by capacitive couplings between strips of the charge readout plane and in the electronics of the data acquisition. These induced signals are studied and compared to capacitance and pulsing measurements on one anode module and an equivalent circuit model is introduced to quantitatively describe this crosstalk.