Characterization of ASIC-based signal readout electronics for LEGEND-1000

In the field of low-background neutrino and dark matter experiments, there is a series of experiments utilizing high-purity germanium (HPGe) detectors. Ge-based p-type point-contact detectors are ideal for such experiments due to their unique properties that enable the measurement of weak signals with excellent energy resolution. The second phase of the Large Enriched Germanium Experiment for Neutrinoless Double-Beta Decay program, LEGEND-1000, is a ton-scale experimental program with unprecedented sensitivity in the search for neutrinoless double beta decay in the Ge-76 isotope. The success of this experiment relies on its operation in a deep underground laboratory and the selection of radio-pure, low-mass materials for detector system construction. The close proximity of its signal readout electronics to the detectors is crucial in maximizing the experiment's discovery sensitivity by retaining HPGe's intrinsic energy resolution with minimal degradation and facilitating pulse shape analysis capabilities for background rejection. However, this proximity also presents unique challenges for the radiopurity of the electronics. The Application-Specific Integrated Circuit (ASIC) technology offers a solution by integrating the entire charge-sensitive amplifier into a single low-mass chip, thereby reducing electronic noise and power consumption. In this presentation, I will discuss the benchmarking of an ASIC prototype for the LEGEND-1000 experiment, focusing on its characteristics such as signal rise and decay times, dynamic range, linearity, and signal-to-noise ratio.