Nonlocal thresholds for improving the spatial resolution of pixel detectors

Abstract

Pixel detectors only record signals above a tuned threshold in order to suppress noise. As sensors become thinner, pitches decrease, and radiation damage reduces the collected charge, it is increasingly desirable to lower thresholds. By making the simple, but powerful observation that hit pixels tend to be spatially close to each other, we introduce a scheme for dynamic thresholds. This dynamic scheme can enhance the signal efficiency without significantly increasing the occupancy. In addition to presenting a selection of empirical results, we also discuss some potential methods for implementing dynamic thresholds in a realistic readout chip for the Large Hadron Collider or other future colliders.

Improving the Spatial Resolution of Silicon Pixel Detectors through Sub-pixel Cross-coupling

“…A different approach enhancing the spatial resolution is to make use of capacitive coupling between readout electrodes, an effect already extensively studied for strip detectors [8,9]. Recent work indicates the possibility of beneficial cross-coupling also for pixel detectors [10,11]. In this paper, we propose a sensor layout where dedicated inter-pixel capacitances are used to enhance capacitive charge sharing.…”