Timing performance of thin Low-Gain Avalanche Detectors (LGADs).

The work here presented concerns the characterization and performance study of the first very thin Low-Gain Avalanche Detectors (LGADs) prototypes produced by the Fondazione Bruno Kessler (FBK). Due to its excellent timing performance, this technology is already being considered for many detector upgrades. However, the future-generation experiments, like ALICE 3 in LHC Run 5, have further increased the interest in the R&D of high-resolution timing detectors, aiming to achieve a resolution of the order of $20 {ps}$. A thinner LGAD design could allow to reach this value. Here, LGADs with a thickness of $25 \mu m$ and $35 \mu m$ have been considered. After a full characterization through laboratory measurements followed by preliminary studies using an infrared laser, these sensors were tested for the first time in a beam test setup at PS, CERN. Several measurements on this new generation of LGADs will be shown in the contribution, including many extracted characteristics, such as drift electric field, noise and charge distributions. Finally, the results of a comprehensive analysis on the timing performance will be reported as a function of the gain (voltage) and sensor characteristics.