Speaker
Description
Noble liquid time projection chambers (TPCs) are essential detector technologies in dark matter searches and neutrino experiments. A key performance parameter for these detectors, whether using liquid argon or liquid xenon, is the electron lifetime. This work presents a low-noise, high-precision electron purity monitoring system developed for such applications. The system comprises two main components: a drift chamber and a charge amplifier, carefully designed to minimize electric field leakage and reduce systematic uncertainties. The electron source can be either laser-generated photoelectrons or emissions from radioactive sources. Experimental results show that the amplifier achieves a gain of -333.33 mV/pC with a noise level below 1 mV. The system maintains excellent linearity across an input charge range from 6 femtocoulombs (fC) to 6 picocoulombs (pC). It enables continuous, real-time monitoring of electron lifetime, particularly valuable during purification. Sharing a single amplifier for both signal collection and readout eliminates the need for separate calibration and further reduces systematic errors. This poster will present the system schematic and report the current status of measurements.
