Speaker
Description
Over the last decade, Low-Gain Avalanche Diode sensors (LGADs) and Resistive Silicon Detectors (RSDs) have significantly advanced silicon detector capabilities. LGAD sensors provide much improved time resolution thanks to the fast and large signals with optimized signal-to-noise ratio, achieving resolutions of 30 ps with 50 um-thick sensors. The addition of a resistive read-out to LGADs, as in the RSD sensors, enables precise concurrent measurement of the particle position, with spatial resolutions below 5% of the sensor pitch. These capabilities make RSDs a very promising candidate for silicon-based 4D tracking detectors of the future High Energy Physics experiments.
RSDs are now available in two implementations, each defined by a different coupling between the read-out electrodes and the resistive layer. In this work, we present a preliminary comparison of AC-coupled (RSDs) and DC-coupled (DC-RSDs) resistive LGADs, fabricated at Fondazione Bruno Kessler (FBK). The performance of the two designs, in terms of spatial and temporal resolution, reconstruction efficiency and occupancy limit, is presented. The sensors have been studied using infrared TCT, TCT-TPA and 120 GeV-pion test-beam measurements. These results provide useful guidance for further optimization of the design.