Speaker
Description
The Super Tau-Charm Facility (STCF) is the next-generation electron-positron collider proposed by China, featuring a center-of-mass energy range of 2-7 GeV. To meet the high-precision particle identification requirements of the STCF, Ring Imaging Cherenkov (RICH) detectors have been extensively studied. The photodetector for the RICH system is required to possess high gain and large-area coverage. A novel RICH detector based on a double micro-mesh structure (DMM) integrated with a photocathode was developed, leveraging its advantages of high gain, large-area scalability, and potential for good time resolution.
In this study, Garfield++ simulations were employed to optimize the mesh parameters, electric field settings, and working gas of the DMM detector. Reflective Cesium Iodide (CsI) photocathodes with a thickness of approximately 500 nm were successfully deposited on the top mesh. The quantum efficiency of the CsI photocathode deposited on the stainless steel mesh was verified to be consistent with that on the gold-plated PCB surface. Prototypes with a sensitive area of 32 cm × 32 cm achieved a gain exceeding 1 × 10⁵ (tested with 5.9 keV X-rays), with a gain uniformity better than 15%. Cosmic ray and beam tests were performed to study the performance of the DMM-based photodetector, as well as the performance of the Cherenkov radiator and the CsI photocathodes. The results confirmed that the prototypes are capable of meeting the requirements for single photoelectron detection. These results demonstrate the feasibility and promising performance of the DMM-based RICH detector, indicating its great potential as a high-performance photodetector solution for the STCF and experiments.
| Name of the speaker | Xu Wang |
|---|---|
| Eligible for the Georges Charpak Young Scientist Award. | yes |