Results for pixel and strip centimeter-scale AC-LGAD sensors with a 120 GeV proton beam

We present a comprehensive evaluation of strip and pixel AC-LGAD sensors tested with a 120 GeV proton beam, examining the impact of design parameters on their temporal and spatial resolutions. Our findings indicate that reducing the thickness of pixel sensors significantly improves their time resolution, with 20-μm-thick sensors achieving approximately 20 ps. Uniform performance is achievable with optimized sheet resistance, making these sensors suitable for future timing detectors. However, 20-μm-thick strip sensors exhibit greater jitter than similar pixel sensors, adversely affecting their time resolution despite experiencing reduced Landau fluctuations compared to the 50-μm-thick versions. Furthermore, low resistivity in strip sensors limits signal size and time resolution, whereas higher resistivity enhances performance. This study underscores the importance of optimizing the n+ sheet resistance and suggests that further advancements should target specific applications such as the Electron-Ion Collider or other future collider experiments. Additionally, we report the detailed performance of four AC-LGAD sensor designs as potential candidates for specific detector applications. These developments position AC-LGADs as promising candidates for future 4D tracking systems, contingent on developing specialized readout electronics.