Rate capability and magnetic field tolerance measurements of fast timing microchannel plate photodetectors

Microchannel plate photodetectors provide both picosecond time resolution and sub-millimeter position resolution, making them attractive photosensors for particle identification detectors of a future U.S. Electron Ion Collider. We have tested the rate capability and magnetic field tolerance of 6 × 6 cm2 microchannel plate photodetectors fabricated at Argonne National Laboratory. The microchannel plate photodetector is designed as a low-cost all-glass vacuum package with a chevron pair stack of next-generation microchannel plates functionalized by atomic layer deposition. The rate capability test was performed using Fermilab’s 120 GeV/c primary proton beam, and the magnetic field tolerance test was performed using a solenoid magnetic with tunable magnetic field strength up to 4 T. The measured gain of the microchannel plate photodetector is stable up to 75 kHz/cm2 and varies depending on the applied magnetic field strength and the rotation angle relative to the magnetic field direction. •Design of fast timing microchannel plate photodetector is described.•Rate capability and magnetic field tolerance of MCP photodetector are studied.•Performance of MCP photodetector is stable up to 75 kHz/cm2, and varies depending on magnetic field strength and rotation angle.•Optimization direction to enhance MCP photodetector magnetic field tolerance is addressed.