Speaker
Description
High Rate Picosecond Photon Detectors (HRPPDs) are large area photosensors, based on Micro-Channel Plate (MCP) technology, that result from a long-lasting collaboration between academy and industry. These photon detectors have excellent time resolution down to 20 ps for single photon detection. They have high Quantum Efficiency ($>$30%) and low Dark Count Rates (few kHz/cm$^2$). HRPPDs are a short stack of fused silica glass window with multi alkali photocathode on one side, two $\sim$10$\times$10 cm$^{2}$ MCPs with capillary diameter of 10 $\mu$m and pixel anode of pitch 3.25 mm . Typical HRPPD gain is $\sim$10$^7$ at the recommended operating bias of 700 V across each of the MCPs. HRPPDs are the baseline photosensor of a proximity focusing RICH (pfRICH) of the Electron-Proton/Ion Collider (ePIC) experiment at the Electron Ion Collider (EIC). They are also considered for a high performance DIRC (hpDIRC) of the same experiment.
In this contribution, we present the results of aging studies performed with an HRPPD photosensor in 2025. Simulation studies show that the HRPPD photosensors, that will be installed near the beampipe in the ePIC detector, will receive substantial radiation. In order to simulate the effects of the radiation accelerated ageing studies are performed. The measurement strategy is to expose a small area of the photocathode to substantial light illumination and monitor a degradation of the Quantum Efficiency and the effective Photon Detection Efficiency as a function of the integrated photon flux as well as the output charge generated in the electron multiplication process. We will also present the HRPPD response as a function of rate. Both studies are performed in INFN Trieste laboratory.
| Position | Postdoctoral researcher |
|---|---|
| Affiliation | INFN Trieste |
| Country | Italy |